Dissertations / Theses on the topic 'Implant-supported prosthesi'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Implant-supported prosthesi.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
TOMMASATO, GRAZIA. "THE REGENERATION OF EDENTULOUS ATROPHIC RIDGES: PROS, CONS, AND EFFECTIVENESS OF THREE DIFFERENT SURGICAL OPTIONS." Doctoral thesis, Università degli Studi di Milano, 2021. http://hdl.handle.net/2434/804105.
Full textSmith, Christopher David. "Prosthodontic maintenance of implant-supported prostheses." Master's thesis, Faculty of Dentistry, 2001. http://hdl.handle.net/2123/4667.
Full textFransson, Hannah. "Implant-supported zirconia-based fixed dental prostheses - a literature review." Thesis, Malmö högskola, Odontologiska fakulteten (OD), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19651.
Full textThe increasing interest in ceramic materials has mostly centered on zirconia-based ceramics lately. Zirconia-based fixed dental prostheses (FDPs) is an ongoing subject of discussion. There are a few articles published on the subject but with varying quality and there is no review on implant-supported zirconia-based FDPs to be found. The purpose of this study is to evaluate available studies on zirconia-based implant-supported FDPs, reporting the results from clinical studies.Three electronic databases were searched for studies reporting on zirconia-based FDPs. The electronic search was complemented by a hand-search made from the reference lists of the retrieved full-text articles. The search result yielded 4,253 titles. Based on pre-established criteria, 5 full-text articles were obtained. One study did not separate the results between tooth-supported and implant-supported groups, why it was excluded from further analysis. Three studies reported on cross-arch restorations, and the majority of the FDPs included were cross-arch restorations. Sufficient data for calculation of cumulative survival-and complication-rates was available in 4 studies. Analysis was based on 47 implant-supported FDPs. This review concludes that cross-arch implant-supported zirconia-based FDPs could be considered as a treatment alternative. The results are, however, based on small number of studies with relatively few FDPs included thus interpretation of the results should be made with caution. Further studies are needed to evaluate how these types of constructions stand the test of time.
Östman, Pär-Olov. "On various protocols for direct loading of implant-supported fixed prostheses /." Göteborg : Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy, Göteborg University, 2007. http://hdl.handle.net/2077/7617.
Full textFischer, Kerstin. "On immediate/early loading of implant-supported prostheses in the maxilla /." Göteborg : Dept. of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy, Göteborg University, 2008. http://hdl.handle.net/2077/9436.
Full textGupta, Saurabh. "Maxillary Changes Under Conventional Dentures Opposing Mandibular Implant-Supported Fixed Prostheses." Thesis, Faculty of Dentistry, 1998. http://hdl.handle.net/2123/5100.
Full textTang, Ling. "A within-subject comparison of mandibular long-bar and hybrid implant-supported prostheses." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0015/NQ43038.pdf.
Full textZardawi, Faraedon M. M. "Characterisation of implant supported soft tissue prostheses produced with 3D colour printing technology." Thesis, University of Sheffield, 2013. http://etheses.whiterose.ac.uk/3299/.
Full textPérez, Delgado José Delfín. "Prótese implanto‒suportada aparafusada vs. cimentada." Master's thesis, [s.n.], 2015. http://hdl.handle.net/10284/5069.
Full textA procura de reabilitações orais cada vez mais próximas dos dentes naturais contribuiu para a evolução das técnicas de reabilitação oral, nomeadamente na área da implantologia, onde atualmente são levantados vários paradigmas, entre os quais se encontra a discussão entre a utilização de próteses cimentadas versus as próteses aparafusadas. Neste trabalho é feita uma revisão da literatura e uma comparação em relação aos dois tipos de retenção de prótese fixas implanto‒suportadas. Para isso foram analisados vários fatores com influência no sucesso ou insucesso dos dois tipos de restaurações como: estética, oclusão, resistência, retenção, biomecânica, reversibilidade, ajuste passivo, efeitos biológicos, provisionalização, função imediata e hábitos parafuncionais. A resposta a esta discussão só é possível de ser obtida após uma exaustiva avaliação de cada caso de reabilitação, ponderando as vantagens e desvantagens de cada técnica, não havendo uma resposta geral para a questão de qual o melhor tipo de retenção. The search for oral rehabilitations more and more close from the natural teeth had contributed for the evolution of the oral rehabilitation techniques, namely in the implantology field, where nowadays are lifted several paradigms, among which is the discussion among the use of cement‒retained or screw‒retained prostheses. In this work it is done a literature review and a comparison in relation to the both types of implant‒supported fixed prostheses retention.For that propose several factors with influence on the success or failure of the both type of restorations were analyzed, such as: aesthetics, occlusion, resistance, retention, biomechanics, retrievability, passivity, biological effects, provisionals, immediate function and parafunctional activity. The answer to this discussion it’s only obtained after an exhaustive evaluation of each rehabilitation case, considering the advantages and disadvantages of each technique, without having a general answer for the question which is the best type of retention.
Butignon, Luís Eduardo. "Influência do tipo de pilar de resistência mecânica pré-ciclagem, quantidade de toque retido e desajuste vertical pré e pós-ciclagem, com análise estrutural em MEV /." Araraquara : [s.n.], 2011. http://hdl.handle.net/11449/105498.
Full textBanca: Rafael Leonardo Xediek Consani
Banca: Luiz Fernando Pegoraro
Banca: Ana Carolina Pero
Banca: Regnata Garcia Fonseca
Resumo: Problemática: De ocorrência clínica comum, o afrouxamento dos parafusos que compõe uma prótese sobre implante é uma complicação que traz transtornos tanto para o profissional quanto para o paciente. Entre os fatores que interferem na estabilidade da união parafusada destaca-se a pré-carga gerada durante o torque do parafuso, as formas como as forças se dissipam através do conjunto implante/pilar/parafuso e as características dos componentes utilizados. Proposição: O objetivo deste estudo foi analisar comparativamente três tipos de pilares sobre implantes, quanto a resistência mecânica previamente ao ensaio de carga cíclica; a porcentagem de torque retido na união parafusada e os níveis de desajuste vertical entre o pilar e o implante antes e após ciclagem; e alterações estruturais na base de assentamento dos pilares através de microscopia eletrônica de varredura (MEV). Material e método: Quarenta e cinco implantes, com conexão tipo hexágono externo foram incluídos em cilindros de PVC utilizando-se resina epóxica com módulo de elasticidade semelhante à estrutura óssea. Os grupos foram estabelecidos de acordo com o tipo de pilar utilizado (n=15): Titânio (pré-fabricado), Ouro (com cinta metálica pré-fabricada e sobre fundido) e Zircônia (pré-fabricado). Cinco pilares de cada grupo foram submetidos a teste de resistência estática para estabelecimento do valor da força a ser utilizada no ensaio de carga cíclica. Os outros 10 pilares de cada grupo foram fixados sobre os respectivos implantes através de parafuso de titânio, sob torque e retorque de 32 Ncm (pilares metálicos) e 20 Ncm (pilar de zircônia). Os corpos de prova foram submetidos à aferição do torque retido (précarga) e dos níveis de desajuste vertical... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Purpose: The aim of this study was to evaluate comparatively three type of abutment in regard to mechanical resistance before cyclic loading, the maintenance of the applied torque and vertical misfit in abutment/implant interface before and after cyclic loading, and damage surface by SEM. Material and Method: Forty five external hex implants were embedded in an epoxy resin and received your respective abutments, randomly divided in three experimental groups (n=15): (A) machined titanium (Ti) abutments; (B) premachined gold (Au) abutments and (C) machined zirconia (ZrO2) abutments. For all groups, only one type of screw was used. The abutment screws were tightened according to the manufacture's recommended torque. Initially, a static bending test was performed using 5 specimens of each group to determine the load applied in the cyclic loading test. Thus, 10 specimens of each group were used to measure the reverse torque value (preload) of the abutment screw and vertical gap between the abutments and implant, before and after loading. The tests were performed according to ISO norm 14801. A cyclic loading (0,5 x 106 cycles; 15 Hz) between 11 - 211 N was applied at an angle of 30 degrees to the long axis of the implants. Group means were compared using ANOVA and Tukey test. Result: The mechanical strength test showed that the UFL mean for Au abutments was significantly higher than the mean of the other abutments (p<0.001). The analysis of reverse torque (preload) before cyclic loading showed no significant differences among abutment groups. After cyclic loading the lowest decrease in preload was observed in group Ti, whereas the highest was observed in group ZrO2, with significant differences between them. The group Au showed an intermediate decrease, with no significant difference to the other groups. In relation to the vertical misfit... (Complete abstract click electronic access below)
Doutor
Esfandiari, Shahrokh. "Oral health technology assessment : study of mandibular 2-implant overdentures." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115892.
Full textFor the first part, a cross-sectional survey was sent to all licensed Canadian Dentists to measure the adoption and provision of implant technology. For the second part, we used the data on the first 140 edentulous elders who were enrolled in a randomized controlled clinical trial to compare the effects of mandibular conventional (CD) and 2-implant overdentures (IOD) on nutrition. The change in patient ratings of satisfaction after treatment, laboratory costs and the number of unscheduled visits were compared. For the last part, edentulous elders (N=36) who were wearing maxillary dentures and either a mandibular conventional denture (CD, n=13) or a two-implant overdenture (IOD, n=23) participated in this study. Participants' preference was measured during a 20-minute interview.
Multivariate regression analysis on the data from the first part of the study shows that the Dentist's gender, province of practice, specialty, and whether they practice alone or in association with other practitioners, are significantly associated with the adoption of implant technology (p<0.05). It is also shown that there was no difference in satisfaction scores for either prosthesis between the groups treated by experienced specialists or new dentists. Furthermore, it is shown that IOD wearers were willing to pay three times more than the current cost of conventional dentures for implant prostheses (p<0.05).
Overall, the results of this study 1) inform decision makers on what types of clinicians provide implant technology and 2) suggest that, with minimal training, all dental clinicians irrespective of their specialty, can provide successful implant overdenture prostheses that edentulous patients are willing to pay for.
Luthi, Leonardo Flores 1984. "Desajuste marginal e influencia na pre-carga de parafusos e nas tensões induzidas as fixações de pilares metaloplasticos sobre-fundidos." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289179.
Full textDissertação (mestrado) - Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-15T12:37:57Z (GMT). No. of bitstreams: 1 Luthi_LeonardoFlores_M.pdf: 40460066 bytes, checksum: 7100a1650e58ebfc4a879fff3da50814 (MD5) Previous issue date: 2010
Resumo: Pilares tipo UCLA calcináveis são de ampla aplicabilidade na Implantodontia, pois permitem a manipulação em laboratório a custo reduzido e a individualização das próteses em função de cada paciente. Entretanto, apresentam piores resultados de adaptação marginal que os pilares pré-fabricados, embora estes agreguem custos significativamente superiores. Pilares UCLA metaloplásticos para sobre-fundição surgiram neste interstício, com prerrogativas de menores custos que os pré-fabricados e melhor adaptação que os calcináveis. Atualmente encontram-se, predominantemente, com base em liga de Ni-Cr-Ti ou Co-Cr. Todavia, não há dados relativos ao seu desempenho após a sobre-fundição, tão pouco, diante das ofertas, qual seria a melhor escolha. O objetivo neste estudo foi avaliar os desajustes marginais e a influência na indução de tensão e no destorque de parafusos protéticos de próteses confeccionadas com pilares UCLA metaloplásticos confrontando seus resultados com pilares UCLA calcináveis. Foram confeccionadas quarenta infraestruturas metálicas simulando próteses parciais fixas de três elementos retidas por dois implantes osseointegrados, obtidas por fundição a partir de transferências realizadas no modelo mestre. As estruturas foram separadas em quatro grupos (n=10) : G1, cilíndros protéticos tipo UCLA metaloplásticos com base em Co-Cr; G2, cilíndros protéticos tipo do UCLA calcináveis e fundidos em liga de Co-Cr; G3, por cilíndros protéticos tipo UCLA metaloplásticos com base em Ni-Cr-Ti; e G4, por cilíndros protéticos tipo do UCLA calcináveis e fundidos em liga de Ni-Cr-Ti. Para mensuração dos valores de desajuste marginal foi utilizada a técnica do parafuso único, o método de extensometria foi usado para análise das tensões, e os valores de pré-carga dos parafusos, após a ciclagem mecânica, foram obtidos por meio de torquímetro eletrônico digital. Os dados de desajuste marginal e tensão foram verificados antes e após a ciclagem mecânica, já os valores de pré-carga foram obtidos em intervalos de 100 mil ciclos. Os dados foram submetidos à análise variância (Três Fatores), seguidos de teste de Tukey (p=0,05) e a presença de correlação foi verificada por meio do teste de Pearson. Não foi encontrada diferença significativa entre os tipos de pilares para o desajuste, tensão e pré-carga. Os valores médios para desajuste (µm) foram G1 (3608,7 ± 1429,6) G2 (7918,3 ± 5055,9) G3 (4577,3 4017,2) G4 (9824,2 ± 1100,6). Os valores médios para tensão (gf) foram G1 (7918,3 ± 5208,8) G2 (3608,8 ± 2335,9) G3 (9824,3 ± 4125,5) G4 (4577,3 ± 15510,3). Os valores médios de pré-carga (Ncm) dentre os ciclos 0 (11,7 ± 3,8), 100 mil (9,7 ± 3,4), 200 mil (8,9 ± 3,7), 300 mil (9,3 ± 3,2), 400 mil (9,7 ± 3,4), 500 mil (10,6 ± 4). O uso de pilares metáloplasticos não reduziu os valores de desajuste marginal e tensão quando comparados aos calcináveis. A liga de Co-Cr apresentou os menores valores de desajuste marginal. O tipo de pilar e a liga utilizada influenciaram negativamente na perda de pré-carga. Não existe correlação entre tensão, desajuste marginal e pré-carga.
Abstract: Castable UCLA abutments are of wide applicability in dental implants, because they allow the manipulation in the laboratory at low cost and individualization of abutments for each patient. However, they show the worse results of marginal adaptation then the fabricated, although these aggregate costs significantly higher. UCLA premachined abutments for casting came in this interstice, with those of a lower cost than pre-made and better adaptation of the abutment. Nowadays, they are manufactured predominantly based on Ni-Cr-Ti or Co-Cr alloys. However, there is no data on its performance after the overcasting, and little is known about which one would be the best choice. Thus, the aim of this study was to analyze the marginal misfit and its influence on tension induction and in preload values of prosthetic screws in prostheses made with premachined UCLA abutmens. Forty frameworks were prepared simulating three-element metal fixed partial dentures retained by two osseointegrated implants, which were obtained through casting of acrylic resin frameworks waxed in a master model. The structures were distributed into four groups (n = 10): Group 1- premachined Co-Cr UCLA abutment; Group 2- casted Co-Cr UCLA abtument (control group 1); Group 3- premachined Ni-Cr-Ti UCLA abutment and Group 4- casted Ni-Cr-Ti UCLA abutment (control group 2). To measure the values of marginal misfit the single screw technique was used. The method of strain gage was used to analyze the stresses; and the values of preload of the bolts after cycling mechanics, were obtained by means of digital electronic torque meter. The data of marginal misfit and strain were obtained before and after of the mechanical cycling, but the values of pre-load were obtained at intervals of 100 thousand cycles. The data were submitted to variance analysis (Three-Way), followed by Tukey test (p=0.05) and the presence of correlation was verified by means of the Pearson correlation. The average values for marginal misfit (µm) were, G1 (3608.7 ± 1429.6), G2 (7918.3 ± 5055.9), G3( 4577.3 ± 4017.2), G4 (9824,2 ± 1100.6). The average values for tension (gf) were: G1 (7918,3 ± 5208.8), G2 (3608.8 ± 2335.9), G3 (9824.3 ± 4125.5) and G4 (4577.3 ± 15510.3). The averages values of preload (Ncm) among the phases: 0 (11.7 ± 3.8), 100 thousand (9.7 ± 3.4), 200 thousand (8.9 ± 3.7) 300 thousand (9.3 ± 3.2), 400 thousand (9.7 ± 3.4), 500 thousand (10.6 ± 4). The use of premachined UCLA abutment did not reduce the values of marginal misfit and strain when compared with the plastic UCLA abutments. The alloy of Co-Cr showed the lowest values of marginal misfit. The kind of abutmetns and alloy used influenced the values of preload. There was no correlation between strain, marginal misfit and preload.
Mestrado
Protese Dental
Mestre em Clínica Odontológica
Rodrigues, Mariana Agustinho 1987. "Avaliação da precisão de diferentes técnicas para obtenção de modelos de trabalho de próteses implantorretidas." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289177.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-19T22:04:29Z (GMT). No. of bitstreams: 1 Rodrigues_MarianaAgustinho_M.pdf: 1199483 bytes, checksum: a7e857503f4eeab6a93e110c0445bc98 (MD5) Previous issue date: 2012
Resumo: O intuito deste trabalho foi comparar diferentes técnicas de preenchimento do molde com gesso e verificar uma metodologia que fosse precisa o bastante para o julgamento das técnicas. Foram obtidos 40 modelos de gesso a partir de uma matriz metálica simulando uma situação clinica de prótese fixa implantorretida de três elementos. Os 40 modelos foram confeccionados segundo quatro técnicas de preenchimento do molde com gesso tipo IV (n=10), sendo assim foram obtidos os seguintes grupos: Grupo 1- 10 modelos de trabalho a partir do preenchimento do molde com gesso em porção única; Grupo 2- 10 modelos de trabalho obtidos a partir do preenchimento do molde com gesso em duas porções; Grupo 3- 10 modelos de trabalho obtidos segundo a técnica do manguito; Grupo 4- 10 modelos de trabalho obtidos a partir do preenchimento do molde com gesso realizando-se a união prévia dos análogos com haste metálica. Foi confeccionada estrutura metálica em titânio utilizada para mensurar os dejasustes marginais e tensão. Os desajustes verticais foram avaliados por meio de observação de desajuste marginal em microscópio com aumento de 120X e 0,1?m de precisão segundo protocolo do parafuso único para teste de passividade em estruturas implantorretidas. A análise de tensão ocorrida sobre a barra metálica foi avaliada por extensometria pela adaptação de dois strain gauges. Os dados foram submetidos à análise variância (ANOVA-1 fator), seguidos de teste de Tukey (?=0,05) para comparação entre os grupos. Foi avaliado presença de correlação entre tensão e desajuste vertical utilizando-se teste de Pearson. Não houve diferença estatística entre as técnicas de preenchimento do molde avaliadas quando comparados os valores de desajuste marginal (p=0,979), entretanto, quando se compara os valores médios de tensão sobre a barra, foi observado diferença estatística significante entre as técnicas do manguito e da união rígida dos análogos de implante (p=0,027). Desta forma, a técnica de união rígida dos análogos previamente a moldagem apresentou resultados similares à técnica convencional e uma técnica adequada para obtenção de modelos de trabalho. A utilização de strain gauges mostrou-se adequada para a avaliação de tensões ocorridas sobre a barra e comparação entre as técnicas de obtenção de modelos de gesso. Não houve correlação entre desajuste marginal e tensão ocorrida na barra
Abstract: The aim of this study was to evaluate the precision of four different mold filling techniques and verify an accurate methodology to evaluate these techniques. It was obtained 40 casts using four from a metallic matrix simulating three unit implant retained prosthesis. The molds were filled using four different techniques (n=10) following the four groups (n=10): Group 1- casts obtained with a single portion filling technique; Group 2- by using a two-step filling technique; Group 3- by using the latex cylinder technique; Group 4- by joining the implant analogues previously to the mold filling. A titanium framework was obtained used as reference to evaluate the marginal misfit and tension forces in each cast. The vertical misfit was measured with an optical microscope with an increase of 120 times following the single screw test protocol. The strain was quantified using strain gauges. Data were analyzed by ANOVA- 1 way and Tukey test (?=0,05). The correlation presence between strain and vertical misfit was evaluated by Pearson test. The misfit values did not present statistic difference (p=0,979). The strain results showed statistic difference between groups 3 and 4 (p=0,027). The splinting technique was considered as efficient as the conventional technique. The strain gauges methodology was accurate on strain measurements and cast distortion evaluation. There was no correlation between strains and marginal misfit
Mestrado
Protese Dental
Mestre em Clínica Odontológica
Sigua-Rodriguez, Eder Alberto 1986. "Resistência à tração de três diferentes sistemas de retenção utilizadas em próteses auriculares implanto-suportadas = Retention strength of three retained auricular prosthesis systems implant-supported." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289411.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-27T15:59:26Z (GMT). No. of bitstreams: 1 Sigua-Rodriguez_EderAlberto_M.pdf: 2176821 bytes, checksum: b803d24031ee26b312d3a029527cb4c4 (MD5) Previous issue date: 2015
Resumo: Defeitos auriculares são causados geralmente por cirurgias oncológicas ablativas, malformações ou traumas. Prótese auricular é dentre as próteses faciais, a que se propõe a restaurar artificialmente ou aloplasticamente as lesões totais ou parciais da orelha. A retenção da prótese auricular pode ser mecânica, adesiva ou implanto-retida, assim o uso de implantes osseointegráveis para retenção de próteses auriculares tem trazido benefícios na estabilidade. Diferentes sistemas de retenção têm sidos utilizados com especificidades em relação às características na retenção, indicação e limitações. O presente trabalho teve como objetivo avaliar o comportamento mecânico de três sistemas de retenção de próteses auriculares quando submetidos à ciclagem mecânica. Doze modelos de resina acrílica com dois implantes instalados distando 20 mm entre si foram obtidos e divididos em três grupos, estes foram considerados como fatores de estudo: I - Barra-clipe (Sistema INP® - São Paulo - Brasil); II - Magneto (Metalmag® - São Paulo - Brasil ) e III - Ball/O-ring (Sistema INP® - São Paulo - Brasil). Cada grupo foi composto por quatro amostras, que foram submetidas ao teste de ciclagem mecânica de remoção e inserção (f = 0,5 Hz) para determinar a resistência à tração. A máquina servo-hidráulica MTS 810-Flex Test 40 (Eden Prairie, MN- USA) foi utilizada para realizar a ciclagem, com um deslocamento de 2.5mm e uma velocidade de 10 mm/s. Os valores da força de retenção foram obtidos em sete tempos (Inicial, 540, 1080, 1620, 2160, 2700 e 3240). Os dados foram comparados utilizando o teste Kruskal Wallis no programa SPSS 18.0. Os resultados foram considerados estatisticamente significativos para valores de p<0.05. O grupo retido pelo sistema barra-clipe apresentou maior força de resistência à tração (29,61 N) com diferença estatisticamente significativa quando comparado com o grupo retido pelo sistema ball/o-ring (9,41 N) e com o sistema com magnetos (8,62 N). Os grupos com retenção promovida por magneto e pelo sistema ball/o-ring diferiram com significância estatística somente para a tração inicial, que se mostrou maior no sistema ball/o-ring (p<. 05). Ao finalizar o teste de ciclagem o sistema barra-clipe garantiu maior retentividade, os sistemas avaliados apresentam força de resistência à tração compatível com o uso clínico e não tiveram fraturas dos componentes durante a avaliação de simulação de três anos de inserção e remoção
Abstract: Auricular defects are generally caused by ablative cancer surgeries, malformations or traumas. Auricular prosthesis is among the facial prosthesis used to restore artificially or alloplastic the partial or total lesions that effects of the auricular. The auricular prosthesis retention can be mechanical, adhesive or implant-supported. Therefore the use of osseointegrated implants for the retention of auricular prosthesis have brought benefits regarding stability, also different retained auricular systems have been used to show the differences between retention, display and limitations. This study aimed to evaluate the mechanical behavior of 3 retained auricular prosthetic connections when submitted to a mechanical cycling test. To conduct the present study, twelve acrylic resin models with installed implants positioned parallel at 20 mm apart were obtained and divided into three groups according to their retention system with four samples in each group. Three retained auricular prosthesis systems implant-supported: I - Bar-Clip system (INP® System - São Paulo - Brazil); II - Magnet System (METALMAG Ltda® - São Paulo - Brazil) and III - Ball/O-ring system (INP® System - São Paulo - Brazil) were considered as study factors. Each of the samples were submitted to the pull-out test (f = 0,5 Hz) to determine its tensile strength. The mechanical cycling test was performed using the servo-hydraulic machine MTS 810-Flex Test 40 (Eden Prairie, MN- USA) that had a 2.5mm shift at a 10 mm/s velocity. The retaining strength for each of the samples were obtained at 7 intervals: 1st - Initial cycles, 2nd- 540 cycles, 3rd- 1080 cycles, 4th- 1620 cycles, 5th 2160 cycles, 6th 2700 cycles, and, finish interval 3240 cycles. Kruskal-Wallis test was used to compare the differences in tensile strength and statistical analysis was performed using SPSS 18.0 for Windows, p values ?0.05 were considered significant. The tensile strength for the group retained by the bar-clip system (29,61 N) was higher with statistically significant difference when compared to the group retained by the ball/o-ring system (9,41 N) and magnets system (8,62 N). The groups retained by the magnets system and the ball/o-ring system differed with statistical significance only for the initial traction, which was higher for the ball/o-ring system (p?0,05). At the end of the cycling test, the bar-clip system ensured greater retentiveness. The evaluated systems showed a tensile strength compatible with the clinical use and no fractures of the components during the simulation of three years of insertion and removal were observed
Mestrado
Cirurgia e Traumatologia Buco-Maxilo-Faciais
Mestre em Clínica Odontológica
Xiang, Lixin [Verfasser]. "The clinical retrospective analysis of fixed and removable implant-supported prostheses in edentulous patients-a 10-year study / Lixin Xiang." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2009. http://d-nb.info/1023374366/34.
Full textRibeiro, Lívia Forster 1978. "Avaliação biomecânica de próteses parciais fixas implantossuportadas na região anterior da maxila = Biomechanical evaluation of implant-supported fixed partial prosthesis in the maxilla anterior region." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287946.
Full textTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-27T03:27:19Z (GMT). No. of bitstreams: 1 Ribeiro_LiviaForster_D.pdf: 4328252 bytes, checksum: 494acc1965c2ac87efb51ae7bd545445 (MD5) Previous issue date: 2015
Resumo: A reabilitação com próteses fixas implantossuportadas na maxila é uma das melhores opções, quando indicada, sendo consagrada na literatura. Entretanto, devido à alta exigência estética nesta região, a reabilitação com implantes, unitária ou múltipla, é bastante desafiadora tanto para o profissional como para o paciente. Nesse sentido, não somente a estética, mas também os fatores mecânicos atuantes nessas reabilitações, são de extrema importância para a longevidade do tratamento. Dessa forma, o posicionamento e o número dos implantes a serem instalados na maxila anterior têm sido fatores decisivos no planejamento do caso, tanto sob o ponto de vista estético quanto mecânico. Nesse estudo foi avaliada a influência da quantidade e disposição dos implantes na distribuição de tensões nos implantes, componentes e reabilitação protética em diferentes disposições de implantes (04 implantes (4I), 02 implantes na região dos incisivos centrais (CS), 02 implantes sendo um no incisivo central e um no incisivo lateral oposto (CSLS), 02 implantes na região dos incisivos laterais (LS)) na região anterior da maxila, por meio do método tridimensional (3D) de elementos finitos (MEF). Foram obtidos quatro modelos 3D compostos pelas seguintes estruturas: região anterior da maxila (porção cortical e trabecular), implantes cilíndricos em titânio (3.75x11mm) de interface protética do tipo cone Morse, mini-pilares em titânio, infraestrutura em zircônia e coroas cerâmicas. O tecido ósseo e as coroas foram obtidas por meio de imagem tomográfica cone Beam. Os implantes, pilares e infraestrutura protética foram criados a partir do programa CAD (Computer Aided Design) SolidWorks®. Posteriormente os modelos foram exportados para o programa computacional de análises numéricas ANSYS Workbench® para análise e obtenção dos resultados. Foi utilizado um carregamento de 150N, distribuídos nas faces palatinas das coroas protéticas, a 45° em relação ao longo eixo das coroas. Os dados obtidos mostraram a distribuição de tensões e os maiores e menores valores de tensões equivalentes de von Mises (MPa) de cada modelo. O número de implantes revelou uma importante influência no comportamento mecânico das reabilitações e demais componentes, justificados pelos menores valores de tensão encontrados no modelo 4I, em todos os seus componentes (112MPa/Implantes, 93MPa/Pilares, 61MPa/Infraestrutura e 53 MPa/coroas cerâmicas). Todavia, quando o número diminuiu para dois implantes, como visto no modelo LS, constatou-se uma maior concentração de tensão em todas as estruturas avaliadas (654MPa/Implantes, 716 MPa/Pilares, 200 MPa/Infraestrutura e 182 MPa/coroas cerâmicas). O modelo CS, e o modelo CSLS mostraram comportamento mecânico semelhantes entre si, porém com valores de tensão menores que o modelo LS e maiores que o modelo 4I (295 e 412 MPa/Implantes, 174 e 228 MPa/Pilares, 195 e 80 MPa/Infraestrutura e 121.17 e 107 MPa/coroas cerâmicas respectivamente). Conclui-se que um número maior de implantes para suportar próteses parciais fixas, distribui as tensões incididas nos implantes e componentes, de maneira mais uniforme e em menores quantidades, o que pode sugerir, que do ponto de vista mecânico, uma maior longevidade do tratamento reabilitador da região anterior da maxila
Abstract: : The oral rehabilitation with implant-supported fixed prosthesis in the maxilla is the most suitable option and is widely enshrined in the literature. Due to the high requirement aesthetics in this area, the rehabilitation with implants, single or multiple, is a big challenge for both the professional and the patient. In this sense, not only the aesthetics but also the mechanical factors acting in these rehabilitations are very important to the longevity of treatment. Thus, the positioning and the number of the implants to be installed in the anterior maxilla have been decisive factors in the planning of the case, both from the aesthetic and mechanical point of view. In this study was evaluated the influence of the number and the arrangement of the implants in stress distribution in the implants, components and prosthetic rehabilitation in different arrangements (04 implants (4I), 02 implants in the region of the central incisors (CS), 02 implants being one the central incisor and the opposite lateral incisor (CSLS) implants 02 in the region of the lateral incisors (LS)) in the anterior maxillary area by means of the method three-dimensional (3D) finite element method (FEM). The 3D models were obtained and they contained the following structures: anterior maxillary region (cortical and trabecular bone), cylindrical titanium implants (3.75x11mm) prosthetic interface type Morse taper, abutments in titanium alloy, zirconium framework and ceramic crowns. Bone tissue and the crowns were obtained by tomographic cone Beam image. The implants, abutments and prosthetic framework were created from the CAD computer software (Computer Aided Design) SolidWorks®. Subsequently the models have been exported to the computer software of numerical analysis ANSYS Workbench® for analysis and achievement of results. The magnitude of the force applied on each unit was 37,5N distributed on the palatine faces of the prosthetic crown, at a 45° angle to the long axis of each crowns, i.e. the total load applied to the prosthesis was 150N. The data obtained emphasized the stress distribution and the higher stress values the equivalent von Mises (MPa) of each model. The number of implants revealed a significant influence on the mechanical behavior of rehabilitation and other structures, justified by the lower stress values found in the model 4I, in all its components (112 MPa/Implants, 93 MPa/Abutments, 61MPa/Framework and 53 MPa/Ceramic crowns). However, when the number has decreased to two implants, as seen in the LS model, there was a higher concentration of tension in all the evaluated structures (654MPa/Implants, 716 MPa/Abutments, 200 MPa/Framework and 182 MPa/Ceramic crowns). The CS and the CSLS models showed similar mechanical behavior to each other, but with lower stress values that the LS model and larger than the 4I model (295 and 412 MPa/Implants, 174 and 228 MPa/Abutments, 195 and 80 MPa/Framework and 121.17 and 107 MPa/Ceramic crowns respectively). It was concluded that a larger number of implants to support a FPPs, distributed the stresses on the implants and in the structures more evenly and in a smaller amounts, which might suggest the greater longevity of the rehabilitation of treatment especially under the mechanical point of view
Doutorado
Protese Dental
Doutora em Clínica Odontológica
Kanashiro, Lucio Hirokuni. "Avaliação da precisão de duas técnicas de união de estruturas metálicas - brasagem e soldagem a laser - em uma prótese clássica de Brånemark pelo método da microscopia eletrônica de varredura (MEV)." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/23/23137/tde-11112005-145236/.
Full textIn this study we assess precision of two union techniques, brazing and laser welding, in metallic structures of a Brånemark classical prosthesis. Ten structures cast in NiCr were segmented in four parts and analyzed in the SEM in pre-established points, vestibular and proximal, in a total of 8 analysis points for each structure. In this first phase, we measured the marginal fissure between the implant analogous and the UCLA abutment before the union of these segments using brazing and laser welding. After this initial analysis, we randomly divided the ten structures in two groups. The group that would be united by the process of brazing, using gas/oxygen blowpipe, presented an average marginal fissure of 5,94µm and the group that would be united by laser welding, an average marginal fissure of 7,22µm. The segments of each metallic structure were screwed with 10Ncm to the respective analogous of the work platform and united with acrylic resin Pattern Resin LS (GC America Inc., USA). After polymerization of the resin, the structure was unscrewed and submitted to process of brazing or laser welding and analyzed in the SEM in the same positions pre-established before the union. This analysis was made in the same work platform. To do so we rotated the four fixation screws until we felt a light resistance. At this moment, only the screw of one of the edges received a torque of 10Ncm and the other screws were released. The average of the marginal fissures after the brazing process was 18,80 µm and the average of the marginal fissures after the laser welding process was 12,38µm. The analysis of the covariance showed that the difference of the fissures after and before the union using brazing was bigger than the difference of the fissures obtained with the laser welding (p = 0,001). Despite the fact that the brazing presents a distortion significantly bigger when compared to the laser welding, both techniques showed clinically acceptable values of marginal fissures. However, it is clear how easy the execution of the laser technique is in relation to the brazing, mainly in relation to the time that is needed for each technique.
Oliveira, Brunamélia de. "Resistência à fratura de infraestruturas de próteses totais implantossuportadas em função de diferentes desenhos de cantilever e espessura do conector distal : estudo in vitro /." Araçatuba, 2016. http://hdl.handle.net/11449/143922.
Full textBanca: Paulo Henrique dos Santos
Banca: Humberto Gennari Filho
Banca: Juliana Aparecida Delben
Banca: Erica Alves Gomes
Resumo: O o bjetivo do presente trabalho foi avaliar, por meio de teste de compressão, a resistência à fratura de infraestruturas metálicas de próteses totais implantossuportadas do tipo protocolo de Branemark em função de diferentes designs ( comprimentos e altura) do cantilever, b e m como espessura do conector distal . Foram confeccionadas 39 infraestruturas ( barras ) em liga de CoCr agrupadas de acordo com o comprimento d o cantilever (cc) (12mm, 19mm e 26mm), altura do cantilever (hc) (3, 2 mm, 4mm) e espessura do conector distal (ec) (0,4mm, 1,5mm e 2mm). Os grupo foram divididos em Controle (cc 12mm; hc 4mm; ec 1,5),Grupo 1 (cc 12mm ; hc 4mm; ec 0,4mm), Grupo 2 (cc 12mm; hc 3,2mm; ec 0,4mm), Grupo 3 (cc 12mm; hc 3,2mm; ec 1,5mm), Grupo 4 (cc 19mm; hc 4mm; ec 1,5mm), Grupo 5 (cc 19mm; hc 4mm; ec 0,4mm), Grupo 6 (cc 19mm; hc 3,2mm; ec 1,5mm), Grupo 7 (cc 19mm; hc 3,2mm; ec 0,4mm), Grupo 8 (cc 26m m; hc 4mm; ec 1,5mm), Grupo 9 (cc 26mm; hc 4mm; ec 0,4mm), Grupo 1 0 (cc 26mm; hc 3,2mm; ec 1,5mm) e Grupo 1 1 (cc 26mm; hc 3,2mm; ec 0,4mm). Tod o s o s espécimes foram submetid o s a ensaio de compressão em uma maquina de ensaio universal com célula de carga de 5000N e velocidade constante de 0,5mm/min . Os dados obtidos foram submetidos a analise estatística ANOVA a três critérios, seguido pelo teste de Tukey, com nível se significância de 5% (p< 0,0 5 ). Foi observada uma diferença significante na diminuição de re sistência a compressão com o aumento do comprimento do cantilever, um aumento significante de resistência nos grupos com altura de cantileveres maiores . Foi concluído que quanto menor o comprimento e maior a altura do cantielver, maior será a resistência. Já a espessura do conector influenciou a resistência, porém sem uniformidade.
Abstract: The aim of this study was to evaluate, thr ough compression test, the fracture strength of metal infrastructure dentures implant of the Branemark protocol type for different designs (length and height) of the cantilever and thickness of the connector distal. 39 were prepared infrastructure (bar) po oled CoCr alloy according to the length of the cantilever (cc) (12mm, 19mm and 26mm), the cantilever height (hc) (3.2mm, 4mm) thick and the distal connector ( c) (0.4mm, 1.5mm and 2mm). The group were divided into control (cc 12mm; hc 4mm and c 1.5), Group 1 (cc 12mm; hc 4mm, 0.4mm c), Group 2 (cc 12 mm; hc 3.2mm, 0.4mm and c) Group 3 (cc 12 mm; hc 3.2mm, 1.5mm c), Group 4 (cc 19mm; hc 4mm, 1.5mm c), Group 5 (cc 19mm; hc 4mm, 0.4mm c), Group 6 (cc 19mm; hc 3.2mm, 1.5mm c), Group 7 (cc 19mm; hc 3.2mm, 0.4mm c), Group 8 (cc 26mm; hc 4mm, 1.5mm c), Group 9 ( cc 26mm; hc 4mm, 0.4mm c) Group 10 (cc 26mm; hc 3.2mm, 1.5mm c) and Group 11 (cc 26mm; hc 3.2mm, 0.4mm and c). All specimens were subjected to compression test in a universal testing machine with 5000N load cell and constant speed of 0.5 mm / min. Data were analyzed by ANOVA statistical analysis three criteria, followed by Tukey test, with significance level was 5% (p <0.05). a significant difference in the decrease of resistance to compression with increasi ng length of the cantilever, a significant increase in resistance groups with height greater cantilevers was observed. It was concluded smaller length and greater height of cantielver, the greater the resistance. Already the connector thickness influenced the resistance, but without uniformity.
Doutor
Rama, Glauber Macedo. "Próteses parciais fixas apoiadas sobre conexão dente-implante rígida: análise do comportamento biomecânico antes e após ciclagem mecânica." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/58/58131/tde-12122014-103741/.
Full textThe association between tooth and implant in fixed partial dentures (FPD′s) have been questioned for many years due to its clinical implications, including selecting the best kind of connection design (rigid or semi-rigid connection). This study assessed cemented toothimplant supported rigid connected FPD′s on 3 types of implant connections (external hexagon - EH, internal hexagon - IH and morse taper - MT) and its relationship to the vertical misfit and FPD failure before and after mechanical cycling plus the photoelastic analysis of those situations. 21 specimens (7 EH, 7 IH and 7 MT) were fabricated on a master model that simulated tooth loss of elements 46 and 47, with an implant placed on the 47 area and a prepared tooth with simulated periodontal ligament in polyether on the 45 area. On this model, three-element metalloceramic rigid FPD′s were made, cemented to tooth and implant (universal post). The specimens were prepared and subjected to mechanical cycling with a 120N load under 1,000,000 cycles, simulating a 2-year clinical use of the prosthesis. Analyses of vertical misfit were performed by optical microscopy (40x) in all periods of FPD′s fabrication (before welding, after welding, after application of ceramic and after cycling). The FPD failure percentage after cycling was also evaluated (cracks/fractures/loss of cementation), and photoelastic test was performed (dental load only, simultaneous abutment load and occlusal load). The results for vertical misfit indicated a significant increase in the levels of misfit for all stages of fabrication for both tooth and implant (p<0.0001) but not significant between groups (p>0.059). For the FPD failure percentage, we found a decreasing rate in the order MT>IH>EH. The photoelastic test indicated a major amount of tension increase in the order MT<IH<EH. Based on these results, within the limitations of the study it was concluded that: the levels of vertical misfit tend to increase in the prosthesis fabrication steps for all implant connections; mechanical fatigue tends to interfere on vertical misfit in long term due to deformation of the framework depending on its thickness; the FPD failure percentage tends to be proportional to the rigidity increase of the implant connection; despite the decrease of rigidity of the implant connection favors the longevity of the FPD, this also tends to increase tensions on the abutments and stress on the surrounding bone; the use of subcrestal morse taper connection on rigid tooth-implant FPD′s tends to be preferable for the preservation of the abutments due to the lower abutment stress concentration at the expense of longevity of FPD, though this can be replaced if the failure is irreversible.
Ayub, Karen Vaz. "Avaliação clínica e radiográfica de implantes curtos: estudo retrospectivo no período de 7 anos." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/25/25146/tde-11062018-194524/.
Full textEdentulous areas with severe bone resorption have been rehabilitated with fixed prostheses installed on short implants, avoiding surgeries of bone reconstruction. This retrospective study describes the behavior of short implants evaluated during 7 years. The sample consisted of 70 patients, of both genders, who received 136 implants, 6 or 8mm in length (Straumann® bone level and tissue level standard plus) on which single and multiple, cemented and screwed prostheses were installed. Clinical and radiographic evaluations were performed by measuring implant stability by resonance frequency, marginal bone loss by panoramic radiographs, plaque and marginal bleeding rates, the implant and prostheses survival rates. Two implants installed in mandible were lost, resulting in a survival rate of 98,3%. The prostheses survival rate was 100%; mean bone loss was -0,28mm; mean implants stability was 76,52 ISQ; mean plaque and bleeding indexes were 32,83% and 33,21%, respectively. The implant stability was higher in the mandible than in the maxilla (p = 0.006). The results obtained in this research make it possible to state that short implants can be used safely within their specific indications.
Pieralli, Stefano [Verfasser]. "Clinical outcomes of partial and full-arch all-ceramic implant-supported fixed dental prostheses : a systematic review and meta-analysis / Stefano Pieralli." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2020. http://d-nb.info/1223928489/34.
Full textMikeli, Aikaterini. "Porcelain fractures in implant borne fixed dental prostheses and single crowns A retrospective clinical study." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-153594.
Full textEinführung: Unter den technischen Komplikationen bei festsitzenden implantatgetragenen Restaurationen zählen Verblendkeramikfrakturen zu den häufigsten. Ziel der vorliegenden klinischen retrospektiven Studie war die Bestimmung der Häufigkeit des Auftretens und Ausmaßes von Verblendkeramikfrakturen und möglicher Risikoindikatoren. Methode: Die Studie wurde in der Abteilung für Zahnärztliche Prothetik der UniversitätsZahnMedizin Carl Gustav Carus Dresden, Technische Universität Dresden (TUD) geplant und durchgeführt. Erwachsene Patienten (Alter ≥ 18 Jahre), die im Zeitraum von Januar 1995 bis August 2011 mit festsitzenden implantatgetragenen metall- oder vollkeramischen Restaurationen versorgt worden waren, wurden nachuntersucht. Dabei wurden demografische und klinische Parameter erhoben. Unter relativer Trockenlegung wurden alle Restaurationen systematisch auf Verblendkeramikfrakturen untersucht. Die Frakturen wurden in vier Gruppen je nach Ausmaß und Reparierbarkeit klassifiziert. Die Analyse der Daten erfolgte deskriptiv. Weiterhin erfolgte eine Kontingenztafelanalyse der Beziehungen zwischen den demografischen und klinischen Parametern und vorliegenden Verblendkeramikfrakturen auf Patienten-, Restaurations- und Einheitenebene. Ergebnisse: Eine Gesamtzahl von 144 Patienten wurde untersucht; 66 davon männlich und 78 weiblich. Es lagen 507 Einheiten (483 metallkeramisch/MK, 24 vollkeramisch/VK) vor, entsprechend 291 implantatgetragenen Einzelkronen/ verblockten Kronen (278 MK, 13 VK), 28 implantatgetragenen Brücken (28 MK, 0 VK), 16 Verbundbrücken (14 MK, 2 VK) und 14 implantatgetragenen Extensionsbrücken (13 MK, 1 VK). 23,6% der Patienten wiesen mindestens eine Verblendkeramikfraktur auf, wobei 16,4% der MK Brücken, 12,2% der MK Kronen und 9,5% der MK Einzeleinheiten betroffen waren. Die Ergebnisse für die VK Restorationen waren 33,3%, 0,0% und 4,2%. Es konnten Korrelationen zwischen den vorhandenen Veblendkeramikfrakturen und den Parametern Bruxismus, Alter des Patienten, Geschlecht, Anzahl der vorhandenen natürlichen Zähnen, Implantaten und implantatgetragenen Brücken pro Patient, frühere technische Komplikationen, Implantatsystem, Gegenkieferversrorgung und Verblockung der Einzelkronen ermittelt werden. Schlussfolgerung: Verblendkeramikfrakturen bei festsitzenden implantatgetragenen Restaurationen werden als multikausales Geschehen angesehen. Auf der Basis des vorliegenden retrospektiven Studiendesigns wurde ein männlicher Patient mit Bruxismus, über 60 Jahre alt, mit ≤20 vorhandenen natürlichen Zähnen, nicht verblockten Kronen und früheren technischen Komplikationen als Risikopatient für Verblendkeramikfrakturen identifiziert. Die Ergebnisse geben Anlass zu weiteren prospektiven klinischen Studien
Santiago, Junior Joel Ferreira [UNESP]. "Avaliação da influência de diferentes materiais oclusais na confecção de próteses fixas implantossuportadas unitárias com diferentes diâmetros dos implantes osseointegrados: estudo pelo método dos elementos finitos tridimensionais." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/93588.
Full textFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A literatura científica ainda é escassa em relação à influência de diferentes materiais na confecção de próteses fixas implantossuportadas unitárias em relação aos diferentes diâmetros dos implantes osseointegrados na distribuição das tensões; as suas manifestações e repercussões na prática clínica ainda não estão totalmente esclarecidas, sendo a fundamentação científica indispensável. Assim, o objetivo desta dissertação foi avaliar a influência do material de revestimento oclusal na confecção de prótese fixa implantossuportada unitária com diferentes diâmetros de implantes osseointegrados. Para o estudo foram elaborados 08 modelos, representando cada qual uma secção de osso mandibular (osso esponjoso e cortical), com a presença apenas de um implante (Conexão Master Screw, Sistemas de Próteses, São Paulo, Brasil) do tipo hexágono externo de 3.75 mm x 10 mm (4 modelos) e de 5.00 mm x 10 mm (4 modelos) com coroas de porcelana feldspática, ou de resina acrílica, ou de resina composta ou coroa liga de NiCr. Para confecção dos modelos foram utilizados os programas de desenho assistido: Rhinoceros® 3D 4.0 (NURBS Modeling for Windows, EUA) e SolidWorks® 2006 (SolidWorks Corp, Massachusetts, USA). Os desenhos tridimensionais foram exportados para o programa de elementos finitos NEI Nastran® 9.0 (Noran Engineering, Inc, EUA), para geração da malha, aplicação da carga e análise. Os resultados foram visualizados através dos mapas de tensão von Mises de cada modelo proposto, a fim de avaliar as variações individuais da distribuição das tensões no implante e na coroa; no osso os resultados foram visualizados através dos mapas de tensão máxima principal. Na carga axial (200 N), o osso cortical não mostrou grandes diferenças entre todos os modelos e o osso trabecular sofreu um aumento das tensões por tração...
The scientific literature is still scarce about the influence of different veneering materials used in fabricating superstructures for implant-retained fixed prostheses in relation to different implant diameters on stress distribution, and the manifestations and implications in clinical practice were not clarified. The aim of this dissertation was to evaluate the influence of occlusal material for single implant-supported fixed prostheses with different implant diameters. For this study were simulated 8 models, representing a section of the mandibular bone (trabecular and cortical bone) with a single external hexagonal implant (Master Screw, Conexão Sistema de Prótese ltda., Sao Paulo, Brazil) of 3.75 x 10 mm (4 models) and 5.00 mm x10 mm (4 models) with a crown with different occlusal materials: feldspathic porcelain crowns, or acrylic resin or composite resin crown or NiCr alloy. The models were designed using computer-aided design softwares : Rhinoceros® 3D 4.0 (NURBS Modeling for Windows, USA) and SolidWorks® 2006 (SolidWorks Corp., Massachusetts, USA). The three-dimensional designs were exported to the finite element program NEI Nastran® 9.0 (Noran Engineering, Inc, USA) for mesh generation, load application and analysis. The results were visualized through von Mises stress maps of each model, to assess individual variations of the stress distribution on the implant and crown; bone results were visualized through maps of maximum principal stress. In axial loading (200 N), cortical bone showed no significant differences in all models,on the trabecular bone the tensile stress increased, with regular implant diameter. For non-axial loads (100 N), the cortical bone, the tensile stress increased significantly on the side common the load application, when it reduced the implant diameter; in the trabecular bone showed seemed stress patterns, although more... (Complete abstract click electronic access below)
Butignon, Luís Eduardo [UNESP]. "Influência do tipo de pilar de resistência mecânica pré-ciclagem, quantidade de toque retido e desajuste vertical pré e pós-ciclagem, com análise estrutural em MEV." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/105498.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Problemática: De ocorrência clínica comum, o afrouxamento dos parafusos que compõe uma prótese sobre implante é uma complicação que traz transtornos tanto para o profissional quanto para o paciente. Entre os fatores que interferem na estabilidade da união parafusada destaca-se a pré-carga gerada durante o torque do parafuso, as formas como as forças se dissipam através do conjunto implante/pilar/parafuso e as características dos componentes utilizados. Proposição: O objetivo deste estudo foi analisar comparativamente três tipos de pilares sobre implantes, quanto a resistência mecânica previamente ao ensaio de carga cíclica; a porcentagem de torque retido na união parafusada e os níveis de desajuste vertical entre o pilar e o implante antes e após ciclagem; e alterações estruturais na base de assentamento dos pilares através de microscopia eletrônica de varredura (MEV). Material e método: Quarenta e cinco implantes, com conexão tipo hexágono externo foram incluídos em cilindros de PVC utilizando-se resina epóxica com módulo de elasticidade semelhante à estrutura óssea. Os grupos foram estabelecidos de acordo com o tipo de pilar utilizado (n=15): Titânio (pré-fabricado), Ouro (com cinta metálica pré-fabricada e sobre fundido) e Zircônia (pré-fabricado). Cinco pilares de cada grupo foram submetidos a teste de resistência estática para estabelecimento do valor da força a ser utilizada no ensaio de carga cíclica. Os outros 10 pilares de cada grupo foram fixados sobre os respectivos implantes através de parafuso de titânio, sob torque e retorque de 32 Ncm (pilares metálicos) e 20 Ncm (pilar de zircônia). Os corpos de prova foram submetidos à aferição do torque retido (précarga) e dos níveis de desajuste vertical...
Purpose: The aim of this study was to evaluate comparatively three type of abutment in regard to mechanical resistance before cyclic loading, the maintenance of the applied torque and vertical misfit in abutment/implant interface before and after cyclic loading, and damage surface by SEM. Material and Method: Forty five external hex implants were embedded in an epoxy resin and received your respective abutments, randomly divided in three experimental groups (n=15): (A) machined titanium (Ti) abutments; (B) premachined gold (Au) abutments and (C) machined zirconia (ZrO2) abutments. For all groups, only one type of screw was used. The abutment screws were tightened according to the manufacture’s recommended torque. Initially, a static bending test was performed using 5 specimens of each group to determine the load applied in the cyclic loading test. Thus, 10 specimens of each group were used to measure the reverse torque value (preload) of the abutment screw and vertical gap between the abutments and implant, before and after loading. The tests were performed according to ISO norm 14801. A cyclic loading (0,5 x 106 cycles; 15 Hz) between 11 - 211 N was applied at an angle of 30 degrees to the long axis of the implants. Group means were compared using ANOVA and Tukey test. Result: The mechanical strength test showed that the UFL mean for Au abutments was significantly higher than the mean of the other abutments (p<0.001). The analysis of reverse torque (preload) before cyclic loading showed no significant differences among abutment groups. After cyclic loading the lowest decrease in preload was observed in group Ti, whereas the highest was observed in group ZrO2, with significant differences between them. The group Au showed an intermediate decrease, with no significant difference to the other groups. In relation to the vertical misfit... (Complete abstract click electronic access below)
Bacchi, Ataís 1986. "Influência do material de infraestrutura e do desajuste vertical de próteses parciais fixas implantossuportadas nas tensões transmitidas às estruturas protéticas e ao tecido ósseo peri-implantar." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288548.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-19T19:18:16Z (GMT). No. of bitstreams: 1 Bacchi_Atais_M.pdf: 865962 bytes, checksum: 55e25bc8a48c9b1870a41c704082365a (MD5) Previous issue date: 2012
Resumo: O objetivo neste estudo foi avaliar a influência do material de infraestrutura e diferentes níves de desajuste vertical na concentração de tensões em prótese parcial fixa implantossuportada (infraestrutura e porcelana de cobertura), parafuso de retenção e tecido ósseo peri-implantar durante o assentamento protético e frente à aplicação de carga oclusal. Um modelo tridimensional de elementos finitos de uma porção posterior de mandíbula contendo dois implantes osseointegrados nas posições de segundo pré-molar e segundo molar, suportando uma prótese parcial fixa foi construído utilizando software específico de modelagem (SolidWorks 2010). Modelos de elementos finitos foram obtidos pela importação do modelo sólido ao software de simulação mecânica (ANSYS Workbench 11). Os modelos foram separados em grupos de acordo com o material de infraestrutura (liga de ouro tipo IV, liga de prata-paládio, titânio comercialmente puro, liga de cobalto-cromo ou zircônia) e o nível de desajuste vertical (10 ?m, 50 ?m e 100 ?m) criado na interface prótese-implante do segundo pré-molar. A concentração de tensões foi avaliada nas seguintes condições: (1) assentamento protético; e (2) cargas oclusais simultâneas de 110 N vertical e 15 N horizontal em cada dente. Os resultados obtidos mostraram que as infraestruturas mais rígidas apresentam maior concentração de tensões internas; entretanto, promoveram menores concentrações de tensão sobre a porcelana de recobrimento, em ambas condições avaliadas. Na análise do assentamento protético, materiais mais rígidos para infraestruturas aumentaram os valores de tensão no parafuso de retenção e não causaram diferença relevante nas tensões no tecido ósseo peri-implantar. Quando a carga foi aplicada, o uso de infraestruturas mais rígidas promoveu redução de tensões no parafuso de retenção e no tecido ósseo peri-implantar. Em ambas condições avaliadas um considerável aumento na concentração de tensões foi obsevado em todas as estruturas com a amplificação do desajuste. Nas diferentes simulações, o material de infraestrutura exerceu considerável influência nas tensões transmitidas às estruturas avaliadas, exceto ao tecido ósseo peri-implantar em condições de assentamento. Aumento de tensões em todas as estruturas pode ser observado com o aumento do desajuste
Abstract: The aim in this study was to evaluate the influence of the framework material and vertical misfit on the stresses created in an implant-supported partial prosthesis (framework and porcelain veneer), retention screw and peri-implant bone tissue during the settlement of the prosthesis and under load conditions. A 3-D Finite Element model of a posterior part of a jaw with two osseointegrated implants at the place of the right second pre-molar and second molar supporting an implant-supported fixed partial prosthesis was constructed using specific modeling software (SolidWorks 2010). Finite element models were obtained by importing the solid model into mechanical simulation software (ANSYS Workbench 11). The models were divided into groups according to the framework material (type IV gold alloy, silver-palladium alloy, commercially pure titanium, cobalt-chromium alloy or zirconia) and vertical misfit level (10 ?m, 50 ?m and 100 ?m) created at the second pre-molar implant-prosthesis interface. The stress concentration was evaluated in the following conditions: (1) settlement of the prosthesis; and (2) simultaneous loads of 110 N vertical and 15 N horizontal in each tooth. The obtained results showed that stiffer frameworks presented higher stress concentrations in it and led to lower stresses in the porcelain veneer, in both conditions. In the analysis of settlement of the prosthesis, stiffer framework materials increased the stress values in the retention screw and did not cause a relevant difference in the stresses values in peri-implant bone tissue. When the load was applied, the use of more stiffness frameworks led to lower stresses in the retention screw, and peri-implant bone tissue. In both conditions evaluated, considerable raise of stress concentration was observed in all the structures within misfit amplification. Comparing the results of the different simulations, the framework materials presented a considerable influence on the stress concentration in the structures evaluated, except on the peri-implant bone tissue during the settlement of the prosthesis, while a considerable increase of the stress in all the structures was observed with the increase of the misfit
Mestrado
Protese Dental
Mestre em Clínica Odontológica
Silva, Isabela Rodrigues Teixeira da. "Efeito do parafuso cônico na simulação da mastigação sobre a interface implante/pilar em diferentes relações coroa/implante." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/23/23150/tde-05082016-151221/.
Full textThe aims of this study is to evaluate two different abutment screws designs, a flat head screw (FHS) and a conical head screw (CHS), making sure if different crown/implant ratio (CIR) result changes in the removal torque after mechanical cycling. Initially, the surface area of the FHS and a CHS was measured by digital image analysis of the screws in 3D SolidWorks Software. Forty sets implant/screw/abutment were used, the sets were divided into 4 groups: GROUP A: 10 sets with abutments 9,8mm height, simulating a CIR>1, fixed with FHS; GROUP B: 10 sets with abutments 6,0mm height, simulating a CIR<1, fixed with FHS; GROUP C: 10 sets with abutments 9,8mm height, simulating a CIR>1, fixed with CHS and GROUP D: 10 sets with abutments 6,0mm height, simulating a CIR<1, fixed with CHS. The sets were fixed in acrylic resin angled 30 ° to the long axis. The abutments were fixed to the implants by applying a torque of 35Ncm. The sets were mechanically loaded. The peak load was 100Ncm vertical force and each group was performed for 1,0x106 cycles. The preload and the postload reverse toque was measured with the digital torque meter and recorded. To analyze the results the methodology of ANOVA (significance level of p <= 0, 05) was used followed by Tukey multiple comparisons. In measuring the surface area of the screws, we found that CHS has greater contact area in the abutment/screw interface (4,16mm²) compared to FHS (1,76mm²). Evaluating the factors tested and p-values we have statistically difference between FHS and CHS (p- value < 0,0001), regardless the time of evaluation, the percentage of CHS reverse torque (90,6 %) is higher than FHS reverse torque (80,9%); CIR>1 and CIR<1 does not differ statistically (p-value 0,1203), although the percentage of reverse torque CIR>1 (84,6 %) is smaller than the percentage of reverse torque CIR<1 (86,8%) and the mechanical preload time differ statistically mechanical postloading time (p-value<0,0001 ), whereas the reversal torque in preload time (92,5%) is largest than reversal torque in postloading time (78,9 %). Based on the results and within the limitations of this study, we can conclude that the CHS outperform the FHS, as regards loosening, which features the CHS as a possible improvement in external-hex implants connections. It was also possible to conclude that the CHS design influences the reverse torque after the mechanical loading, being particularly suitable in a situation CIR>1, where the screw is most required.
Suedam, Valdey. "Avaliação da deformação gerada nos componentes intermediários de prótese fixa implanto-suportada com diferentes alturas, com a utilização de extensômetros lineares elétricos." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/25/25135/tde-07022007-143314/.
Full textIn implant-supported prosthesis the different heights of abutments represent different lever arms to which the implants are submitted, leading to a deformation of the components that is not completely understood. The objective of this study was to assess the deformation ocurring in different heights of abutments of mandibular implant-supported fixed prosthesis. A circular master cast made of steel (Steel 1010/20) was used with five perforations containing implant replicas of 3,75mm of diameter in which the abutments were seated. The specimens were divided in two groups of three specimens each, according to the type of alloy of the framework (CoCr or PdAg) and the abutment's height (4,0 mm, 5,5 mm and 7,0 mm), respectively. A force of 100N was applied at a point 15mm distal to the center of the terminal abutment. Readings of the deformations generated on the mesial and distal aspects of the abutment were obtained with the use of strain gauges. The results of this study demonstrated that the deformation observed in the abutments adjacent to the cantilever arm is proportional to the increase of the abutment's height and elastic modulous of the alloy.
Ayub, Karen Vaz. "Avaliação clínica e radiográfica de implantes utilizados como pilares de próteses inferiores implantossuportadas do tipo protocolo, colocadas sob carga imediata, empregando dois sistemas reabilitadores após 7 anos." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/25/25146/tde-03122013-164207/.
Full textThis study evaluated the success of implants used to support mandibular complete full-arch fixed prosthesis employing two rehabilitation systems with immediate loading after 7 years. The following aspects were investigated: plaque and bleeding index, implant stability by resonance frequency analysis and marginal bone loss. The 76 implants were evaluated in 19 patients divided in 2 groups: A (n=12, All-on-four® - Nobel Biocare®) and B (n=7, Neopronto® - Neodent®). The follow-up visits were at the time of implant placement (initial), 6 months, 1, 2 and 7 years after surgery. The results showed a success rate of 100% for implants in group A and 90% for group B. The plaque index did not differ statistically signifcant and were in group A, 71.87%, 63.54% and 47.92%, and in group B 26.78%, 41.07% and 37, 50% for 1, 2 and 7 years of follow-up, respectively. The bleeding index for group A was 43.75%, 42.71% and 43.75% and for group B was 53.57%, 51.79% and 48.21%, for 1, 2 and 7 years of follow-up, respectively, no statistical differences. Suppuration was not observed at any time of evaluation. The results of FR did not differ significantly between groups, however, decreased between initial (group A = 69,27ISQ and group B = 68,29 ISQ) and 6 months (group A = 64,65ISQ and group B = 66,50ISQ), and increased in the following evaluations for both groups, in group A was 66,17ISQ, 66,05ISQ and 69,87ISQ and group B was 67,78ISQ, 68,13ISQ and 73,61ISQ for 1, 2 and 7 years of follow-up, respectively. In relation to bone loss, a significant difference existed between groups and was 0,49mm and 0,67 mm after 1 year and 1,03mm and 1,27mm after 7 years, for groups A and B, respectively. Regarding the position of the implants, group B showed statistical difference between the central and distal implants for FR and bone loss. It was concluded that 1- Success rate was 100% for group A and 90% for group B; 2 - Plaque and bleeding index decreased over the follow-up; 3- FR was similar between groups, but with a significant difference in group A for thw criterion time, and in group B for the criteria evaluation times and position of the implants, 4- bone loss was significantly different between groups, and higher in group B.
Piras, Fernanda Furtado. "Correlação da tensão no intermediário e as medidas de comprimento, altura e angulação de infraestruturas de próteses sobre implantes." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/25/25146/tde-26102015-100543/.
Full textThe passive adaptation and stability have been described as important prerequisites in the choice of materials and manufacturing techniques in implant-supported prosthesis. The aim of this work was to study, with the aid of strain gauges, the average deformation generated in the abutment, after application of axial load on frameworks made up of three different materials. Besides, through confocal laser microscopy, assess the length, height, and angle of these specimens, and abutment. These data were statistically analyzed in order to find possible correlation between the deformation generated, and the internal measures of the framework and the external measure of the abutments they were screwed on. For this research, a model made of polyurethane with two external hexagon implants, positioned in the areas of teeth 43 and 45 was used. From this model, 12 three-element frameworks were fabricated and divided into 3 groups (n = 4), according to the technique used: (C) conventional Ni-Cr casting; (U) machined zirconia CAD / CAM and (S) laser sintered Co-Cr by CAD / CAM. During application of axial load, the tensions generated were recorded by strain gauges attached to the abutments, and evaluated quantitatively and qualitatively. In general, there was a predominance of compression areas, and the few areas of traction showed low values. The laser sintered group was the only one with compressive forces for all sensors. The milled and conventional groups behaved similarly, differing only in a region. Subsequently, the framework and the abutment were analyzed by confocal microscopy for evaluation of angle, length and height of the inner (framework) and outer (abutment) walls in regions corresponding to the location of strain gauges. For the variable angle, all groups showed similar values among themselves and greater than the abutments. As for the variables length and height, all values were different. Regarding the abutments, the values were higher in height and smaller in length. These results were analyzed by Pearson statistical method, leading to the conclusion that, for some regions, there was correlation between deformation and length, and also deformation and angle. The higher the angle and the smaller the length, the greater the deformation shown.
Oliveira, Brunamélia de [UNESP]. "Resistência à fratura de infraestruturas de próteses totais implantossuportadas em função de diferentes desenhos de cantilever e espessura do conector distal: estudo in vitro." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/143922.
Full textRejected by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br), reason: Solicitamos que realize uma nova submissão seguindo as orientações abaixo: A versão final da dissertação/tese deve ser submetida no formato PDF (Portable Document Format). O arquivo PDF não deve estar protegido e a dissertação/tese deve estar em um único arquivo, inclusive os apêndices e anexos, se houver. Por favor, corrija o formato do arquivo e realize uma nova submissão. Agradecemos a compreensão. on 2016-09-21T13:09:53Z (GMT)
Submitted by BRUNAMÉLIA DE OLIVEIRA null (brunamoliveira@hotmail.com) on 2016-09-21T13:51:25Z No. of bitstreams: 1 TESE DOUTORADO Brunamélia de Oliveira-PDF.pdf: 1338467 bytes, checksum: 256bd9b6a59b22460bfa4b2d78f3caa4 (MD5)
Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-09-21T20:35:33Z (GMT) No. of bitstreams: 1 oliveira_b_dr_araca.pdf: 1338467 bytes, checksum: 256bd9b6a59b22460bfa4b2d78f3caa4 (MD5)
Made available in DSpace on 2016-09-21T20:35:33Z (GMT). No. of bitstreams: 1 oliveira_b_dr_araca.pdf: 1338467 bytes, checksum: 256bd9b6a59b22460bfa4b2d78f3caa4 (MD5) Previous issue date: 2016-07-25
O objetivo do presente trabalho foi avaliar, por meio de teste de compressão, a resistência à fratura de infraestruturas metálicas de próteses totais implantossuportadas do tipo protocolo de Branemark em função de diferentes designs (comprimentos e altura) do cantilever, bem como espessura do conector distal. Foram confeccionadas 39 infraestruturas (barras) em liga de CoCr agrupadas de acordo com o comprimento do cantilever (cc) (12mm, 19mm e 26mm), altura do cantilever (hc) (3,2 mm, 4mm) e espessura do conector distal (ec) (0,4mm, 1,5mm e 2mm). Os grupo foram divididos em Controle (cc 12mm; hc 4mm; ec 1,5),Grupo 1 (cc 12mm; hc 4mm; ec 0,4mm), Grupo 2(cc 12mm; hc 3,2mm; ec 0,4mm), Grupo 3 (cc 12mm; hc 3,2mm; ec 1,5mm), Grupo 4 (cc 19mm; hc 4mm; ec 1,5mm), Grupo 5 (cc 19mm; hc 4mm; ec 0,4mm), Grupo 6 (cc 19mm; hc 3,2mm; ec 1,5mm), Grupo 7 (cc 19mm; hc 3,2mm; ec 0,4mm), Grupo 8 (cc 26mm; hc 4mm; ec 1,5mm), Grupo 9 (cc 26mm; hc 4mm; ec 0,4mm), Grupo 10 (cc 26mm; hc 3,2mm; ec 1,5mm) e Grupo 11 (cc 26mm; hc 3,2mm; ec 0,4mm). Todos os espécimes foram submetidos a ensaio de compressão em uma maquina de ensaio universal com célula de carga de 5000N e velocidade constante de 0,5mm/min. Os dados obtidos foram submetidos a analise estatística ANOVA a três critérios, seguido pelo teste de Tukey, com nível se significância de 5% (p<0,05). Foi observada uma diferença significante na diminuição de resistência a compressão com o aumento do comprimento do cantilever, um aumento significante de resistência nos grupos com altura de cantileveres maiores. Foi concluído que quanto menor o comprimento e maior a altura do cantielver, maior será a resistência. Já a espessura do conector influenciou a resistência, porém sem uniformidade.
The aim of this study was to evaluate, through compression test, the fracture strength of metal infrastructure dentures implant of the Branemark protocol type for different designs (length and height) of the cantilever and thickness of the connector distal. 39 were prepared infrastructure (bar) pooled CoCr alloy according to the length of the cantilever (cc) (12mm, 19mm and 26mm), the cantilever height (hc) (3.2mm, 4mm) thick and the distal connector ( c) (0.4mm, 1.5mm and 2mm). The group were divided into control (cc 12mm; hc 4mm and c 1.5), Group 1 (cc 12mm; hc 4mm, 0.4mm c), Group 2 (cc 12 mm; hc 3.2mm, 0.4mm and c) Group 3 (cc 12 mm; hc 3.2mm, 1.5mm c), Group 4 (cc 19mm; hc 4mm, 1.5mm c), Group 5 (cc 19mm; hc 4mm, 0.4mm c), Group 6 (cc 19mm; hc 3.2mm, 1.5mm c), Group 7 (cc 19mm; hc 3.2mm, 0.4mm c), Group 8 (cc 26mm; hc 4mm, 1.5mm c), Group 9 ( cc 26mm; hc 4mm, 0.4mm c) Group 10 (cc 26mm; hc 3.2mm, 1.5mm c) and Group 11 (cc 26mm; hc 3.2mm, 0.4mm and c). All specimens were subjected to compression test in a universal testing machine with 5000N load cell and constant speed of 0.5 mm / min. Data were analyzed by ANOVA statistical analysis three criteria, followed by Tukey test, with significance level was 5% (p <0.05). a significant difference in the decrease of resistance to compression with increasing length of the cantilever, a significant increase in resistance groups with height greater cantilevers was observed. It was concluded smaller length and greater height of cantielver, the greater the resistance. Already the connector thickness influenced the resistance, but without uniformity.
Filho, Hilmo Barreto Leite Falcão. "Análise da força de retenção de cimentos resinosos em modelo representativo da técnica de cimentação passiva para implantes osseointegráveis." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/58/58131/tde-26032010-144643/.
Full textThe aim of this study was to analyze the bond strength of two resin cements used in the passive cementation technique for osseointegrated implants, Panavia F and RelyX U100, evaluating this property on its application in specimens of three different metal types, NiCr (Verabond 2, Dental Aalba), NiCrTi (Tilite Omega, Talladium) and Titanium (Ti c.p., degree 2, Realum), submitted or not to termocycling assay. Ninety six calcined cylinders (Conexão Sistemas de Próteses) had been waxed of standardized form, casted (32 in each type of league) and cemented on titanium cylinders (Conexão Sistemas de Próteses). The specimens were distributed enter 12 groups (n = 8) in accordance with the type of metal, cement and thermocycling. All specimens were submitted to an immersion in distilled water at 37ºC for 24 hours, however only half of them to a termocycling assay in a simulation thermal cycles machine MSCT-3 for 5000 cycles during 30 days. All specimens were submitted to a tensile test in a mechanical test machine EMIC-DL2000 (speed = 5mm/min and cell load = 500Kgf). The statistics analysis evidenced tensile strength of the RelyX U100 cement greater than Panavia F cement independent of the metal league type used with averages until 71,18 Kgf and 55,08 Kgf respectively. The termocycling assay did not show interference in the tensile strength of both cements.
Castilho, Anderson Almeida. "Efeito de dois sistemas de soldagem na alteração dimensional nas ligas de cobalto-cromo verificado por meio de análise por extensometria linear elétrica e resistência à flexão /." São José dos Campos : [s.n.], 2009. http://hdl.handle.net/11449/97350.
Full textBanca: Estevão Tomomitsu Kimpara
Banca: Alfredo Mikail Melo Mesquita
Resumo: O objetivo neste estudo foi avaliar a alteração dimensional provocada pelos procedimentos de soldagem nas infra-estruturas de próteses fixas impanto-suportadas por meio de análise de extensometria linear elétrica assim como se determinar a resistência flexão de dois tipos de juntas soldadas (Arco-Plasma e Laser) em liga Odontológica Co-Cr. Para tanto, estruturas metálicas foram fundidas pelo método de indução para pilares tipo micro-unit. Para esse estudo, foram investigados três grupos: Grupo controle (G I: fundição em Monobloco, n=10), Grupo Arco-Plasma (G II: fundição segmentada e soldagem da estrutura em Arco-Plasma, n=10) e Grupo Laser (G III: fundição segmentada e soldagem da estrutura em LASER, n=10) as quais após assentamento em modelo de análise extensométrica, foram coletadas três leituras de microdeformação (με) para cada amostra. Os grupos, após ensaio de extensometria linear elétrica, foram submetidos ao teste de resistência à flexão (MPa) em máquina de ensaios universal (EMIC, 0,5 mm/min, 500Kg). As médias ±DP dos valores de microdeformação observados para as condições foram para o grupo Monobloco:461,9με; para o grupo Arco-Plasma: 637,0με e para o grupo Laser : 526,8με. Os resultados obtidos após o teste de resistência à flexão foram: para o grupo Monobloco: 1857,2MPa; para o grupo Arco-Plasma: 1820MPa e para o grupo Laser : 1068Mpa. Uma comparação em análise extensométrica entre os três grupos, quanto à distribuição dos valores de alteração dimensional, foi efetuada por meio do teste de Kruskal-Wallis. Verificou-se que a distribuição dos valores de alteração dimensional não difere Estatisticamente (estatística kw = 1,77; gl = 2; p = 0,414 > 0,05). Uma comparação entre os três grupos, quanto à distribuição dos valores... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The aim of this study was to evaluate the dimensional changes caused by the welding procedures in implant-supported prostheses infrastructure by strain gauge analysis as well as to determine the flexural strength values of two types of welded joints (Arc-Plasm and Laser) in Co-Cr dental alloy. Thus, metal structures were casted by induction method for micro-unit type abutment. For this study, three groups were evaluated: Control Group (G I: monoblock casting, n = 10), Arc-Plasm Group (G II: casting and welding of structures in Arc-Plasm, n = 10) and Laser Group (G III: casting and welding of structures in Laser, n = 10), in which were, after placing the samples in the strain gauge analysis model, three micro strain (με) measurements for each specimen were collected. The groups, after strain gauge analysis, were submitted to flexural strength (MPa) test in an universal testing machine (EMIC, 0.5 mm / min, 500Kg). Mean ± SD values of microstrain conditions observed for the Monoblock group were: 461.9 mε; for the Arc-Plasm group: 637.0 mε and the Laser group: 526.8 mε. The results, after flexural strength test, were: Monoblock group: 1857.2 MPa; Arc-Plasm group: 1820 MPa and Laser group: 1068 MPa. The strain gauge comparison analysis between the three groups, as well the distribution of dimensional changes values were made by Kruskal- Wallis test. It was found that the values' distribution of dimensional changes do not differ statistically (KW statistic = 1.77, df = 2, p = 0.414> 0.05). A comparison between the three groups, in relation to the 108 distribution of the values of flexural strength, was performed by Kruskal- Wallis test. It was found that the values distribution of flexural strength differ statistically... (Complete abstract click electronic access below)
Mestre
Hasan, Istabrak [Verfasser]. "Computational Simulation of Trabecular Bone Distribution around Dental Implants and the Influence of Abutment Design on the Bone Reaction for Implant-Supported Fixed Prosthesis / Istabrak Hasan." Bonn : Universitäts- und Landesbibliothek Bonn, 2011. http://d-nb.info/1016151403/34.
Full textTramontino-Mesquita, Vanessa Silva 1982. "Proteses fixas implanto-retidas : influencia do pilar intermediario e dos ciclos de cocção da ceramica nos desajustes e nas tensões induzidas as fixações." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289183.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-10T13:58:31Z (GMT). No. of bitstreams: 1 Tramontino-Mesquita_VanessaSilva_M.pdf: 2155429 bytes, checksum: 5050e6eb80efb708a774530922aee871 (MD5) Previous issue date: 2008
Resumo: Especula-se que ciclos de cocção da cerâmica geram aumento nos desajustes marginais. Em próteses sobre implantes se imagina que possam motivar aumento das tensões induzidas às fixações, tensões estas, que podem variar em função do tipo de pilar protético intermediário entre a prótese e os implantes. Assim, o propósito deste estudo foi avaliar a influência do ciclo de cocção da cerâmica e uso de pilar intermediário no desajuste marginal e nas tensões induzidas aos implantes, produzidas por próteses parciais fixas de 3 elementos parafusadas sobre 2 implantes. Foram confeccionadas 20 infraestruturas metálicas simulando próteses parciais fixas de 3 elementos retidas por 2 implantes osseointegrados e fundidas em titânio comercialmente puro (Ti c.p.), obtidas partir de um modelo mestre. As estruturas foram dividas em 2 grupos, sendo o grupo pilar cônico composto por 10 estruturas retidas por parafusos a pilares intermediários cônicos padrão Branemark com cintas cervicais de 1 mm para peças múltiplas e o grupo UCLA composto por 10 estruturas retidas por parafusos diretamente sobre as fixações utilizando cilindros protéticos tipo UCLA com cintas cervicais de 1 mm sem contra-hexágono de travamento para peças múltiplas. As infra-estruturas de ambos os grupos sofreram simulação dos diversos ciclos de cocção da cerâmica, objetivando a avaliação dos desajustes marginais e das tensões induzidas às fixações. As tensões foram avaliadas por extensiometria e os desajustes por microscopia óptica, sendo aferidos após cada ciclo de cocção, sendo os resultados confrontados com a situação imediatamente pós-fundição (controle). Os valores das tensões foram correlacionados com os valores de desajuste marginal medidos nas interfaces entre pilares e/ou fixações e cilindros protéticos, com aumento de 120 x, obedecendo ao protocolo de aperto do parafuso único, sendo realizados na situação pós-fundição (controle) e após cada ciclo de cocção da cerâmica. Foi realizada a análise de variância em esquema de parcela subdividida, sendo a parcela os grupos de tratamento e os ciclos de cocção da cerâmica, a subparcela. O teste de Tukey foi utilizado para comparação múltipla, com nível de significância de 5%. Não houve diferença significativa (p=0,601) na indução de tensões aos implantes devido ao uso de pilar intermediário (pilar cônico: 580,06 ± 253,93gf; UCLA: 665,35 ± 173,99gf). Porém, notou-se decréscimo nos valores de tensão devido às etapas do ciclo de cocção da cerâmica. A análise do desajuste marginal revelou haver interação entre o grupo de tratamento e o ciclo de cocção da cerâmica (p=0,002), sendo que as menores médias de desajuste ocorreram antes da exposição das infraestruturas aos ciclos de cocção (pilar cônico: 118,07 ± 58,61µm; UCLA: 83,93 ± 25,63 µm). Concluiu-se que a presença de um pilar intermediário cônico em infraestruturas de 3 elementos fundidas em Ti c.p. não reduziu as tensões induzidas às fixações e que os ciclos de cocção da cerâmica causaram aumento no desajuste marginal e redução nas tensões induzidas às fixações.
Abstract: It is speculated that porcelain firing cycles cause an increase on marginal misfit. This effect is imagined to origin an increase on strains around implants, when screwing the metallic frameworks, and it is supposed to be decreased by the use of an abutment between the framework and the implant. Thus, the aim of this study was to evaluate the influence of the porcelain firing cycle and of the use of conic abutments on marginal misfit and on strains around implants originated by screwing 3-element fixed partial dentures over 2 implants. Twenty metallic frameworks were fabricated, casting commercially pure titanium, obtained from a master cast, simulating 3-element fixed partial dentures, retained by 2 implants. The structures were divided into two groups, where conic abutment group was composed by 10 structures screwed to Branemark-type conic multi-unit abutments with 1 mm cervical belts and UCLA group composed by 10 structures screwed directly to the implants using non-engaging multi-unit UCLA cylinders with 1 mm cervical belts. All the frameworks were submitted to porcelain firing cycle simulation, aiming the evaluation of marginal misfit and strains around implants. Strains were analyzed by the use of strain gauges and misfit was analyzed by an optical microscope, both after each firing cycle and the results were confronted to the as-cast situation (control). The strains values were correlated with misfit values, which was measured in the interface of the abutment or implant and the prosthetic cylinder, following the one-screw test, being achieved on the as cast situation and after each firing cycle. Multivariate analysis was applied in a sub divided parcel scheme and the treatments were considered as the parcel and the firing cycles as the sub parcel. Tukey¿s test was employed to multiple comparisons, with significance level at 5%. There was no significant difference (p=0.601) on strains around implants due to the use of the abutment (conic abutment: 580.06 ± 253.93gf; UCLA: 665.35 ± 173.99gf). However, a decrease on strains values was observed, due to the porcelain firing cycle. Misfit analysis presented an interaction between the treatment groups and the firing cycles (p=0.002). The lower misfit mean values occurred before the frameworks were exposed to the firing cycles (conic abutment: 118.07 ± 58.61µm; UCLA: 83.93 ± 25.63 µm). It is concluded that the presence of a conic abutment on a 3 elements partial fixed prosthesis cast in commercially pure titanium did not decrease strains around implants and that the porcelain firing cycles caused an increase on marginal misfit and a decrease on strains around implants.
Mestrado
Protese Dental
Mestre em Clínica Odontológica
Oliveira, José Luiz Góes de. "Resistência à fratura de coroas metalocerâmicas implanto-suportadas cimentadas e parafusadas." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/25/25135/tde-25052009-113714/.
Full textIn implant prosthodontics, the choice of retention system (cemented or screwed) is often related to personal preferences of each professional. However, some aspects that differenciate these 2 types of prosthesis must be considered at the time of selection: the passivity of the fit, the reversibility, the aesthetics, the occlusion and the presence of the occlusal opening of the screw-access hole. The absence of access hole is a great advantage when using cemented prosthesis especially when it comes to cases where aesthetic is a priority. In addition, the discontinuing of the ceramic in the screwed prosthesis may be a factor of weakening. This becomes even more serious when the screw-access hole is totally ceramic in order to minimize its aesthetic deficiency. The aim of this study was to evaluate the resistance to fracture of cemented and screw-retained implant-supported metalloceramic crowns with two different frameworks designs. Moreover, the influence of the aging of ceramics by mechanical cycling on the resistance to fracture under compressive load was also observed. Ten cement-retained, ten screw-retained with the screw-access hole in metal measuring 2mm height (\"chimney\") and ten screw-retained with screw-access hole in ceramic measuring 2mm height (without \"chimney\") single crowns were manufactured. All screw-retained crowns were screwed directly over the implant. Half of the specimens from each group (n=5) were subjected to Mechanical cycling. The load (100N, 1.200.000 cycles, 2 Hz) was applied by a spherical stainless steel tip (6mm in diameter) simultaneously on 4 cusps (2 buccal and 2 lingual), simulating the contact with the antagonist tooth, under water at 37oC. All specimens were subjected to axial compression with a spherical tip (6mm in diameter) in a universal testing machine at 0.5mm/min. Mean values of maximum force required to fracture were analyzed using 2-way ANOVA (1=framework, 2=mechanical cycling) and Tukey\'s test for multiple comparisons (p\' < OR =\'0,5). Mechanical cycling did not affect the strength of the specimens when subjected to compressive load. Cemented prosthesis had greater resistance to fracture than the two variations of screwed frameworks with statistically significantdifferences. Between the 2 types of screwed prosthesis no statistically significant differences were observed.
Castilho, Anderson Almeida [UNESP]. "Efeito de dois sistemas de soldagem na alteração dimensional nas ligas de cobalto-cromo verificado por meio de análise por extensometria linear elétrica e resistência à flexão." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/97350.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O objetivo neste estudo foi avaliar a alteração dimensional provocada pelos procedimentos de soldagem nas infra-estruturas de próteses fixas impanto-suportadas por meio de análise de extensometria linear elétrica assim como se determinar a resistência flexão de dois tipos de juntas soldadas (Arco-Plasma e Laser) em liga Odontológica Co-Cr. Para tanto, estruturas metálicas foram fundidas pelo método de indução para pilares tipo micro-unit. Para esse estudo, foram investigados três grupos: Grupo controle (G I: fundição em Monobloco, n=10), Grupo Arco-Plasma (G II: fundição segmentada e soldagem da estrutura em Arco-Plasma, n=10) e Grupo Laser (G III: fundição segmentada e soldagem da estrutura em LASER, n=10) as quais após assentamento em modelo de análise extensométrica, foram coletadas três leituras de microdeformação (με) para cada amostra. Os grupos, após ensaio de extensometria linear elétrica, foram submetidos ao teste de resistência à flexão (MPa) em máquina de ensaios universal (EMIC, 0,5 mm/min, 500Kg). As médias ±DP dos valores de microdeformação observados para as condições foram para o grupo Monobloco:461,9με; para o grupo Arco-Plasma: 637,0με e para o grupo Laser : 526,8με. Os resultados obtidos após o teste de resistência à flexão foram: para o grupo Monobloco: 1857,2MPa; para o grupo Arco-Plasma: 1820MPa e para o grupo Laser : 1068Mpa. Uma comparação em análise extensométrica entre os três grupos, quanto à distribuição dos valores de alteração dimensional, foi efetuada por meio do teste de Kruskal-Wallis. Verificou-se que a distribuição dos valores de alteração dimensional não difere Estatisticamente (estatística kw = 1,77; gl = 2; p = 0,414 > 0,05). Uma comparação entre os três grupos, quanto à distribuição dos valores...
The aim of this study was to evaluate the dimensional changes caused by the welding procedures in implant-supported prostheses infrastructure by strain gauge analysis as well as to determine the flexural strength values of two types of welded joints (Arc-Plasm and Laser) in Co-Cr dental alloy. Thus, metal structures were casted by induction method for micro-unit type abutment. For this study, three groups were evaluated: Control Group (G I: monoblock casting, n = 10), Arc-Plasm Group (G II: casting and welding of structures in Arc-Plasm, n = 10) and Laser Group (G III: casting and welding of structures in Laser, n = 10), in which were, after placing the samples in the strain gauge analysis model, three micro strain (με) measurements for each specimen were collected. The groups, after strain gauge analysis, were submitted to flexural strength (MPa) test in an universal testing machine (EMIC, 0.5 mm / min, 500Kg). Mean ± SD values of microstrain conditions observed for the Monoblock group were: 461.9 mε; for the Arc-Plasm group: 637.0 mε and the Laser group: 526.8 mε. The results, after flexural strength test, were: Monoblock group: 1857.2 MPa; Arc-Plasm group: 1820 MPa and Laser group: 1068 MPa. The strain gauge comparison analysis between the three groups, as well the distribution of dimensional changes values were made by Kruskal- Wallis test. It was found that the values´ distribution of dimensional changes do not differ statistically (KW statistic = 1.77, df = 2, p = 0.414> 0.05). A comparison between the three groups, in relation to the 108 distribution of the values of flexural strength, was performed by Kruskal- Wallis test. It was found that the values distribution of flexural strength differ statistically... (Complete abstract click electronic access below)
Pita, Murillo Sucena. "Estudo biomecânico de conexões implante/pilar com parafusos convencionais e parafusos modificados tipo Cone Morse: análise tridimensional pelo método dos elementos finitos." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/58/58131/tde-17052013-104258/.
Full textDespite the reliability and high success rates related to treatment with implants, prosthetic rehabilitation failures are still persistent, especially the loosening of the screws holding the abutments. Applying a torque, which generates a preload on the screw, has been its primary means of prevention, although not being able to eliminate it completely. The nature of loosening is complex, and the mechanisms responsible for mechanical failure of the screw connecting the implant systems are not fully elucidated. Changes in designs of connections and prosthetic retaining screws have been developed in order to solve this complication. However, the literature on the optimal configuration of these changes and their biomechanical factors involved is still inconclusive. The objective of this study was to evaluate through three-dimensional finite element analysis, the stress distribution in two different implant systems, external hexagon (EH) and internal triangle (IT), with conventional plan screws and modified Morse Taper screws, establishing up qualitatively the stress maps and quantitatively the values of preload in front of the torque and of pre-established axial and oblique loads. The results showed that, for all models, the external loads exerted no influence on the values of von Mises stress and preload, and that the higher stresses have focused specifically on the spindle of the screws. The IT connection appeared biomechanically more favorable than the EH, with more homogeneous distribution of stresses throughout the whole implant/abutment/screw. Additionally, conventional screws showed significantly lower stress values and higher preload than the modified Morse Taper screws, then, this latter proved to be more susceptible to mechanical failures as loosening and/or fracture.
Erisir, Berberoglu Ilsu [Verfasser]. "Long-term survival analysis of dental implants & implant-supported prostheses in patients after squamous cell carcinoma in head and neck region / Ilsu Erisir Berberoglu." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2021. http://d-nb.info/1234983567/34.
Full textCoró, Vitor. "Análise comparativa da interface entre intermediários e estruturas fundidas e CAD/CAM em Co-Cr e zircônia antes e após queima de cerâmica e ciclagem mecânica." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/58/58131/tde-08082013-154727/.
Full textThe implant-supported prostheses present a high success rate, but there are still reports of technical and mechanical complications, mainly regarding adaptation and loosening of screws. CAD/CAM techniques have been developed trying to improve adaptation and passivity, and today there are many options of materials and systems to work with. The purpose of this study was to evaluate, by microscope, fitting of three elements prostheses retained by two implants, made of different materials, different techniques, before and after ceramic firing. It was also verified if the method/material used, as well as the degree of adjustment would influence on the behavior of the prostheses after a fatigue test. Five groups of ten specimens were formed (n = 10). After reading, ceramic pressing and fatigue test data were submitted to ANOVA and Tukey-Kramer\'s tests. The mean vertical misfit pre and post application of ceramic (μm), whit both screws tightened to G1: Structures casted in Co-Cr with castable cylinders (26.03 ± 18.4) and (36.5 ± 9) G2: Structures casted in Co-Cr, with Co-Cr basis cylinder (4.86 ± 5) (10.5 ± 6); G3: Structures casted in Co-Cr associated with the cemented cylinder technique (0 ± 0) and (0 ± 0); G4: Machined structures in Co-Cr CAD/CAM (0 ± 0) and (2.7 ± 2), G5: Structures machined in zirconia CAD/CAM (14.87 ± 9) and (15.2 ± 8). To the measurement condition of only one side tighted, pre and post ceramic, on the tightned side, the results were G1: 9.63 ± 1 and 34.8 ± 8; G2: 2.37 ± 5 and 11.9 ± 9; G3: 0 ± 0 and 0 ± 0; G4: 0 ± 0 and 3.4 ± 3; G5: 17.69 ± 1 and 20.8 ± 9. To the measurement condition of only one side tightened, pre and post ceramic, on the untightened side, the results were in G1: 124.22 ± 37 and 129.8 ± 37; G2: 64.79 ± 47 and 80.6 ± 46; G3: 12.34 ± 2.1 and 17 ± 3; G4: 5 ± 3.54 and 17.6 ± 8; G5: 37.77 ± 25 and 42.4 ± 19. The loosening torque of the prosthetic screws (Ncm) was checked before and after fatigue test to 300,000 cycles. The mean values were: G1: 5,80 ± 1,23 e 4,11 ± 1,16; G2: 6,30 ± 1,00 e 3,32 ± 0,87; G3: 5,63 ± 1,05 e 3,30 ± 1,46; G4: 7,24 ± 1,05 e 3,44 ± 1,62; G5: 7,75 ± 1,25 e 6,78 ± 1,18. CC groups, Co-Cr CAD/CAM and Zi, showed the best results regarding vertical adjustment, followed by the Co-Cr group and castable. CC groups, Co-Cr and Co-Cr CAD/CAM presented loss of torque after fatigue test. The Zi group showed less loss of torque among all groups, comparing before and after fatigue test. None of the groups showed enough loosening to loose joint stability.
Torres, José Walter Murta 1958. "Influência dos ciclos de cocção da porcelana na força de destorque de parafusos de estruturas implanto-retidas." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289175.
Full textTese (Doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-21T23:50:10Z (GMT). No. of bitstreams: 1 Torres_JoseWalterMurta_D.pdf: 1581851 bytes, checksum: 0bbcce2409164d19a4e51f955b38d595 (MD5) Previous issue date: 2013
Resumo: Este trabalho avaliou a resistência ao destorque em parafusos de estruturas metálicas implanto-retidas fundidas em níquel-cromo (Ni-Cr) após fundição e simulação dos ciclos de cocção da porcelana. Dois implantes hexágono externo - com 3,75 mm de diâmetro - foram posicionados, com o auxílio de um paralelômetro fresador (1000N; Bio-art), na posição de segundo pré-molar e segundo molar num troquel de resina acrílica, de maneira a ficarem parcialmente submersos na resina expondo apenas suas plataformas de adaptação. Foram confeccionados 10 troqueis de resina acrílica (n=10). A partir de cada troquel foi obtida, pelo método de fundição da cera perdida, uma infraestrutura implanto-retida utilizando-se dois cilindros calcináveis tipo UCLA. A amostra foi submetida à força de torque de seus parafusos de fixação a 20 Ncm, registrada por meio de um torquímetro digital de precisão (Torque Meter TQ-8800; Lutron), e reapertados após 10 minutos. A força de destorque foi registrada após 24 horas do torque inicial. A resistência ao destorque foi analisada após fundição da estrutura protética e simulação dos três ciclos de cocção da porcelana (opaco dentina e glaze). Foram obtidas médias de destorque para cada estrutura nas distintas etapas de avaliação no estudo. Os dados foram analisados estatisticamente pelos testes ANOVA one-way e Bonferroni, com nível de significância de 5% (p<0,05). Os valores das médias da força de destorque dos parafusos por fase foram 13,95 ± 1,12 Ncm para pós-fundição, 15,20 ± 1,18 Ncm para ciclo Opaco, 15,85 ± 1,13 Ncm para ciclo Dentina e 16,80 ± 1,03 Ncm para o glaze. A força de destorque dos parafusos após a fundição foi significativamente menor do que a obtida para os grupos que simularam o ciclo de cocção da porcelana (p<0,05). Entre as fases de simulação dos ciclos cerâmicos, observou-se maior valor da força de destorque para o glaze (p<0,05), não sendo observadas diferenças estatisticamente significantes entre as fases opaco e dentina (p>0,05). Foi possível verificar que os ciclos de cocção da porcelana influenciam a resistência ao destorque em parafusos de estruturas metálicas implanto-retidas fundidas em níquel-cromo (Ni-Cr). Observou-se que os valores de destorque aumentaram gradativamente com cada ciclo de cocção da porcelana
Abstract: This study evaluated the resistance to detorque of screws from implant-retained metal structures cast in nickel-chromium (Ni-Cr) after metal casting and simulation of porcelain firing cycle. Two external hex implants - with 3.75 mm diameters - were placed with the help of a parallelometer cutter (1000N; Bio-art), in the position of second premolar and second molar in acrylic resin die, so as to be partially submerged in the resin exposing only their platforms for adaptation. Thereupon, 10 dies were made with acrylic resin (n= 10). An implant-retained infrastructure from each die was obtained by the method of lost wax casting, using two UCLA cylinders. The sample of acrylic structures were subjected to 20 Ncm of torque to its fixing screws registered by means of a precision digital torque wrench (Torque Meter TQ-8800; Lutron) and retightened after 10 minutes. The measure of detorque was recorded 24 hours after the initial torque. The detorque resistance was analyzed after denture casting, followed by the simulation of porcelain firing cycles (opaque, dentin and glaze). Detorque averages were obtained for each structure at different stages of evaluation in this study. Data was statistically analyzed by one-way ANOVA and Bonferroni tests, at 5% significance level (p>0.05). We performed necessary statistical tests. The mean detorque force of the screws per phase were 13.95 ± 1.12 Ncm for post-casting; 15.20 ± 1.18 Ncm for cycle opaque; 15.85 ± 1.13 Ncm for cycle dentin; and 16.80 ± 1.03 Ncm for glazing. The screw's post-casting detorque resistance was significantly lower than that observed for the groups simulating porcelain firing cycles (p<0.05). Among groups simulating ceramic's cycles, the highest detorque resistance was observed for glaze group (p<0.05), with no significant statistical differences among opaque and dentin groups (p>0.05). It was possible that the porcelain firing cycle influenced detorque resistance of screws in implant-retained metal structures cast in nickel-chromium (Ni-Cr). It was observed that detorque values gradually increased after each porcelain firing cycle
Doutorado
Protese Dental
Doutor em Clínica Odontológica
Filho, Hilmo Barreto Leite Falcão. "Avaliação da relação entre o desajuste vertical em interfaces pilar/cilindro protético fundido e sobrefundido e a perda de torque de parafusos protéticos de titânio." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/58/58131/tde-18092006-235019/.
Full textThis study was developed with the objective to evaluate the levels of misfit in abutment / coping joint obtained from casting and pre-machined copings in two different alloys and the torque loosening in prosthetic titanium screws used to connect this joint, analyzing the relation between the two variable. The prosthetic screws were submitted to analyses on scanning electron microscopy before and after the torque. The values of torque were checked by one digital torque meter, the values of misfits were registered by an optic microscope and images of the samples were registered by an digital camera connected to another optic microscope. All the values of misfits and torque loosening was submitted to frequency tests and analyzed by the T and Mann-Whitney tests for the comparison between the groups, and by the Spearman test for the verification of the correlation between the two variable. The results had evidenced significant statistical differences (p ≤ 0,05) for the different types of copings used about misfit (p = 0,000), and had not been evidenced significant statistical differences (p ≤ 0,05) between the copings about the torque loosening (p = 0,052), neither for the different alloys about misfit (p = 0,615) and torque loosening (p = 0,811). The statistical Spearman test analysis confirmed the correlation between the misfit and torque loosening (p = 0,017). It was verified alterations in the surfaces of the threads of the screws after the torque and casting defects in some prosthetic cylinders, especially in the casting cylinders. In accordance with the results, the employed methodology and the limitations of this study, it has been concluded that the pre-machined copings provide more favorable levels of misfits than the casting copings, there is correlation between misfits in the abutment / coping joints and torque loosening in the titanium screws, and casting defects should influence in the misfits.
Gastaldo, José Fabio Guastelli. "Análise fotoelástica das tensões ao redor dos implantes, na região de mandíbula, com aplicação de força em próteses tipo protocolo, revestidas em resina acrílica." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/23/23150/tde-29052013-154831/.
Full textThe purpose of this study was to analyze, using the photoelasticity method, the behavior of stresses occurring in peri-implant structures and fixed prosthesis supports following Brånemark protocol that are screwed on five implants of different lengths, 10mm; 13mm and 15mm, when submitted to occlusal loads. Three mandible photoelastic models were built: MD10; MD13 and MD15, with five implants each, 3.75mm of internal diameter and located in parallel with each other in the interforaminal region. Microunit pillars were installed on each implant model with a 1mm-belt, and a single prosthesis was installed over them with a cobalt/chrome metallic infrastructure covered with thermoplastic acrylic resin. Loads of 1.0 and 3.0 bars were applied and images were photographed and evaluated. Results showed that highest tensions occurred in 10mm-length implants; the patterns of stresses was the same in implants of different lengths and only the magnitude of stresses changed along implant body. The greater the length the lower the stress in the analyzed region of the model. We concluded that: 1) The implants of greater length tension better distributed along the body of the implant. 2) Tensions were located more apically by both mesial and distal implants of greater length. 3) The implants have suffered greater tensions were the closest to the cantilever and implant center.
El-Feky, Ahmed. "The effects of prosthetic rehabilitation and dietary intervention on quality of life, satisfaction and nutritional status in edentulous adults : implant-supported overdentures versus conventional complete dentures." Thesis, University of Newcastle upon Tyne, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.438022.
Full textTannure, Ana Luiza Pinheiro. "Pilares de zircônia confeccionados com a tecnologia CAD/CAM de diferentes sistemas: avaliação da superfície do hexágono do implante, da interface implante/pilar e do destorque." Universidade de Taubaté, 2016. http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=860.
Full textPurpose: To evaluate the vertical misfit (gap) and horizontal discrepancy (dh) in the zirconium (Zr) implant-abutment interface manufactured by three CAD/CAM systems (Neodent Digital, Zirkonzahn and AmannGirrbach) and the ZrTi implant-abutment manufactured by Neodent, before and after cyclic loading. The surface of the titanium (Ti) hexagon implant was also evaluated before and after cyclic loading as well as the torque loss of the abutment screw post loading. Method: The study groups made up of 8 samples were as follows: Zr AmannGirrbach (PZrAG) implant-abutment, Zr Neodent (PZrN) implant-abutment, Zr Zirkonzhan (PZrZ) implant-abutment and Zr implant-abutment with Ti Neodent (PZrTiN) infrastructure. Standard-made abutments were manufactured from three identical abutments milled in wax, fixed on analogs and sent to the participant laboratories. The analysis of the surface, the gap and the dh were performed on three samples from each group and the torque loss was performed on eight samples. Initially, images of the surface of the hexagon implant were obtained by Scanning Electron Microscope (SEM). Then, images from the abutment surfaces were obtained from optical microscope 3D (MO 3D), followed by the tightening of the abutments to the implants with torque of 32.0N.cm. Subsequently, images of the implant-abutment interfaces were obtained from the SEM for comparison with the post loading images. CrCo crowns were cemented on the abutments and the combination (implant/abutment/crown) was submitted to cyclic loading with a load of 400N, frequency of 8.0Hz, for one million cycles. New images of the implant-abutment interface were obtained from the SEM, and initial and final gap measurements were done with evaluation of the dh. The torque loss was measured. For the evaluation of the surface of the implants, new images were obtained from the SEM and compared with the initial situation. The observed changes were classified according to the following categories: none (0), mild (1), moderate (2), intense (3). Results: In relation to the torque loss (N.cm) in the groups of Zr, the PZrZ showed the highest average of 23.12(2.7), followed by the PZrAG of 19.57(4.3) and the PZrN of 19.43(1.9). The measured value for the PZrTiN was 21.0(2.5). In regards to the surface alterations among the Zr groups, the highest change was observed in the PZrZ of 1.3 9(0.99) and the lowest change in the PZrAG of 0.64(0.62). The PZrTiN group presented the following value: 0.53(0.56). In regards to the gap among the Zr groups, the highest average value was evidenced in the PZrAG of 5.19(2.07)μm and the lowest in the PZrN of 3.21(1.47)μm. The PZrTiN group of 1.48(1.04)μm showed an inferior value compared to the PZrN group. Among the Zr abutments, the highest horizontal discrepancy value was observed in the PZrAG of 49.98(9.06) and the lowest value was observed in the PZrZ of 31.53(32.33)μm. The PZrTiN did not present dh. Conclusions: Regarding torque loss, significant differences were not observed among the zirconium groups, as well as among the Neodent groups (Zr and ZrTi). Among the Zr abutments, the largest hexagon surface alterations were observed in the PZrZ group and among the abutments milled by Neodent (Zr and ZrTi) in the PZrN. It was observed that surface changes showed that a relationship is maintained with the shape of the hexagon milled in the abutment. As to the gap among the Zr abutments, no significant difference was noted among the groups; between the Neodent abutments (Zr and ZrTi), before and after cyclic loading significant difference between the two groups was observed only before cyclic loading. When evaluated the gap of each group before and after cyclic loading, only the PZrZ showed significant difference. The groups PZrAG, and the PZrZ showed the highest pre-cycling gap when considered by face-value and in the post loading situation, the abutments suffered inclinations over the implant. As to dh when considering the Zr groups, the lowest average value was found in the PZrZ, and the PZrN showed highest regularity among the four sides observed. All Zr abutments showed horizontal discrepancy alternating different levels of over-contour in the same sample.
Tiossi, Rodrigo. "Avaliação da precisão da adaptação de próteses sobre implantes, fundidas em monobloco, com ligas de Ni-Cr e Co-Cr e em Ti cp, antes e após soldagem a laser e após a simulação da aplicação de cerâmica." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/58/58131/tde-04102006-145650/.
Full textThe purpose of this study was to evaluate the precision of fit of three-element implant-retained and supported frameworks, cast in Ni-Cr- and Co-Cr alloys and commercially pure titanium (Cp Ti). The Sheffield´s test (EISENMAN, 1997) was used to analyze the marginal interfaces, and the readings executed in an optic microscope (Nikon, Japan). Two Master Conect AR (Conexão Sistemas de Prótese, Brazil) internal-hexagon implant systems were used. Data were submitted to analysis of variance (ANOVA) with complementary Tukey-Kramers test. Data analysis showed that: the interfaces, when analyzed as a one-piece casting and with both screws tightened, were better for the group cast in Ni-Cr alloy (25.00 ± 7.92μm), though not statistically different from the two other groups (Co-Cr: 54.23 ± 37.10μm e Cp Ti: 48.41 ± 26.69μm). In the single screw tightened test the three groups showed no statistical difference, with the following results, on the tightened side: Co-Cr: 35.01 ± 27.76μm, Ni-Cr: 20.13 ± 7.97μm, and Cp Ti: 22.28 ± 17.29μm, and on the opposite side: Co-Cr: 118.64 ± 91.48μm, Ni-Cr: 70.66 ± 20.88μm, and Cp Ti: 118.56 ± 51.35μm. On this same study, the one-piece castings were sectioned and laser welded. The laser welding was executed with the Desktop Laser (Dentaurum, Germany) machine. The Sheffield´s test was used to analyze the passive fit, and the readings executed in an optic microscope (Nikon). The procedure of sectioning the one-piece castings and its later laser welding presented statistically significant lower levels of misfit when the castings were analyzed with both screws tightened for the group cast in Co-Cr alloy (21.49 ± 9.08μm). For the other two groups, Ni-Cr alloy (13.10 ± 1.81μm) and Cp Ti (17.70 ± 11.70μm), results presented no statistically significant differences, though showed lower levels of marginal fit. In the single screw tightened test and readings made on the opposite side, only the group cast on Ni-Cr alloy (19.81 ± 7.36μm) didnt present statistically significant lower levels of misfit when compared to single-piece castings. The Co-Cr alloy (41.02 ± 26.15μm) and the Cp Ti (40.42 ± 27.14μm) groups showed statistically significant differences after laser welding. The reading on the screwed side detected that the three groups were statistically the same. Simulation of the porcelain firing cycles did not develop any significant differences on the analyzed interfaces under all readings and screw tightening conditions. The groups cast in Co-Cr alloy and Cp Ti, when analyzed with only one screw tightened and the readings executed on the opposite side, presented lower levels of misfit, being 26.42 ± 8.67μm, after simulation, when was 41.02 ± 26.15μm after laser welding for the first and, 40.42 ± 27.14μm and 28.05 ± 20.89μm, before and after, for the second, though not showing any statistically significant differences.
Santiago, Júnior Joel Ferreira. "Avaliação da influência de diferentes materiais oclusais na confecção de próteses fixas implantossuportadas unitárias com diferentes diâmetros dos implantes osseointegrados : estudo pelo método dos elementos finitos tridimensionais /." Araçatuba : [s.n.], 2010. http://hdl.handle.net/11449/93588.
Full textAbstract: The scientific literature is still scarce about the influence of different veneering materials used in fabricating superstructures for implant-retained fixed prostheses in relation to different implant diameters on stress distribution, and the manifestations and implications in clinical practice were not clarified. The aim of this dissertation was to evaluate the influence of occlusal material for single implant-supported fixed prostheses with different implant diameters. For this study were simulated 8 models, representing a section of the mandibular bone (trabecular and cortical bone) with a single external hexagonal implant (Master Screw, Conexão Sistema de Prótese ltda., Sao Paulo, Brazil) of 3.75 x 10 mm (4 models) and 5.00 mm x10 mm (4 models) with a crown with different occlusal materials: feldspathic porcelain crowns, or acrylic resin or composite resin crown or NiCr alloy. The models were designed using computer-aided design softwares : Rhinoceros® 3D 4.0 (NURBS Modeling for Windows, USA) and SolidWorks® 2006 (SolidWorks Corp., Massachusetts, USA). The three-dimensional designs were exported to the finite element program NEI Nastran® 9.0 (Noran Engineering, Inc, USA) for mesh generation, load application and analysis. The results were visualized through von Mises stress maps of each model, to assess individual variations of the stress distribution on the implant and crown; bone results were visualized through maps of maximum principal stress. In axial loading (200 N), cortical bone showed no significant differences in all models,on the trabecular bone the tensile stress increased, with regular implant diameter. For non-axial loads (100 N), the cortical bone, the tensile stress increased significantly on the side common the load application, when it reduced the implant diameter; in the trabecular bone showed seemed stress patterns, although more... (Complete abstract click electronic access below)
Orientador: Eduardo Piza Pellizzer
Coorientador: Fellippo Ramos Verri
Banca: Paulo Sérgio Perri de Carvalho
Banca: Alcides Gonini Júnior
Mestre
Cunha, Tiago de Morais Alves da. "Desadaptação marginal na interface de pilares cerâmicos procera parafusados a diferentes sistemas de implantes." Programa de Pós- Graduação em Odontologia da UFBA, 2008. http://www.repositorio.ufba.br/ri/handle/ri/10522.
Full textSubmitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-04-24T14:16:56Z No. of bitstreams: 1 Dissertacao - Tiago Cunha.pdf: 763526 bytes, checksum: db4a0e2212c5cc1a1da94e961899507d (MD5)
Approved for entry into archive by Rodrigo Meirelles(rodrigomei@ufba.br) on 2013-05-08T11:50:18Z (GMT) No. of bitstreams: 1 Dissertacao - Tiago Cunha.pdf: 763526 bytes, checksum: db4a0e2212c5cc1a1da94e961899507d (MD5)
Made available in DSpace on 2013-05-08T11:50:18Z (GMT). No. of bitstreams: 1 Dissertacao - Tiago Cunha.pdf: 763526 bytes, checksum: db4a0e2212c5cc1a1da94e961899507d (MD5) Previous issue date: 2008
Embora sejam fabricados pela Nobel Biocare, as vantagens mecânicas e estéticas dos pilares cerâmicos personalizados Procera têm levado à sua utilização em associação com outros sistemas de implantes compatíveis com o sistema Bränemark. Estudos chamam a atenção para o fato de que a associação de componentes de empresas diferentes das dos fabricantes dos implantes gera diferenças estatisticamente significativas na adaptação marginal, quando comparados a implantes parafusados a componentes de um mesmo fabricante. Objetivo. Através deste estudo, buscou-se avaliar, através de microscopia eletrônica de varredura (MEV), a desadaptação marginal na interface entre implante e pilar de pilares cerâmicos personalizados Procera, parafusados a diferentes sistemas de implantes compatíveis com o sistema Branemärk. Métodos. Aplicação de questionário a profissionais especialistas em prótese dentária com perguntas relativas ao planejamento das próteses sobre implantes e aos sistemas sobre os quais esses pilares costumam ser utilizados, a fim de se delinearem os grupos experimentais a serem estudados. Com base nas informações coletadas, foram selecionados doze pilares personalizados Procera em Zircônia e doze implantes de hexágono externo e plataforma regular, compatíveis com o sistema Bränemark, divididos em três grupos com quatro amostras cada: (1) SIN (ES), (2) Conexão (EC) e (3) Nobel Biocare (GCN). Resultados. As médias e desvios padrões determinados para cada grupo foram submetidos à ANOVA e, em seguida, ao Teste Tukey, para se determinar a significância das diferenças entre os grupos estudados. As médias de desadaptação marginal na interface entre implante e pilar para cada grupo foram: 9,53µm ±0,52, 10,62µm ±2,16 e 5,7µm ±0,39, respectivamente para os grupos ES, EC e GCN. Conclusão. Os resultados obtidos evidenciaram uma diferença significativa entre os grupos (p=0,001), com valor de desadaptação marginal menor para o grupo de controle (GCN), enquanto que, para os grupos ES e EC, embora tivessem sido constatados valores similares, eles diferiram estatisticamente dos do grupo de controle, indicando, portanto, maior desajuste.
Salvador
Ayub, Eduardo Antonio. "Estudo de dois sistemas de reabilitação com implantes submetidos à ativação imediata: análise clínica, radiográfica e da estabilidade, por frequência de ressonância." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/25/25135/tde-11102007-143459/.
Full textTwo implant-supported rehabilitation systems were evaluated considering their biomechanical behavior, the area of prosthetic stability, cantilever extensions, stability using resonance frequency analysis (RFA) and clinical parameters, such as: modified plaque index (PI), modified bleeding index (BI), suppuration, distance between the implant shoulder and the mucosal margin (DIM), probing pocket depth (PD), probing attachment level (PAL), bleeding on probing (BP), thickness (TM) width (WM) of keratinized mucosa and radiographic analysis. One hundred and four implants had been installed in twenty six patients, submitted to immediate loading and divided into two groups: A (n=16, All-on-4®-Nobel Biocare) e B (n=10, Neopronto®-Neodent). The prosthesis had been installed in average time of 32h (T0), and controls made in (T6), 12 (T12) and 24 months (T24). As result, the success rate was 100% for the group A and 90% for the group B for both implants and prosthesis. Significant differences (p<0,05) 10,96mm and 18,81mm had been presented between posterior cantilever and the resistance arm (RA) 13,87mm and 5,50mm, respectively for the groups A and B. The stability area, in the group A was of 373,5mm2 and in B of 112,8mm2; the average of RFA (in ISQ) of the group A T0= 68,62; T6=64,40; T12=67,07; T24=66,53 and of the group B T0= 68,37; T6=66,29; T12=67,09; T24=67,10, with differences (p<0,05) between the periods (Group A) and implant position (Group B). The PI in group A was of 1,0 and 0,7 and 0,6 and 0,9 for group B, o BI (0,7), suppuration (absent), DP (presence) in group A=50% and 37,9%; group B=70,1 and 52,1%, in the control of 12 and 24 months, did not present statistical differences between the groups. The average (in mm) of WM for the group A (2,05 and 2,21) and B (2,29 and 2,40) and TM group A (1,53 and 1,56) and B (1,31 and 1,43), DIM of group A (2,54 and 2,52) and B (0,18mm and -0,12mm), DP group.
Gomes, Jéssica Marcela de Luna. "Análise da desadaptação marginal vertical e horizontal de infraestruturas de próteses fixas implantossuportadas confeccionadas através de diferentes técnicas /." Araçatuba, 2018. http://hdl.handle.net/11449/152727.
Full textCoorientadora: Sandra Lúcia Dantas de Moraes
Banca: Fellippo Ramos Verri
Banca: Mônica Maria Albuquerque Pontes
Resumo: O objetivo deste trabalho foi avaliar a desadaptação marginal vertical, horizontal e interna de infraestruturas e próteses fixas implantossuportadas confeccionadas através de diferentes técnicas. Além disso, realizar uma revisão sistemática e meta-análise avaliando o efeito da soldagem de infraestruturas de próteses fixas implantossuportadas em uma melhor adaptação quando comparada as infraestruturas confeccionadas em monobloco. Um total de 30 infraestruturas foram confeccionadas e divididas em 3 grupos: G1) Técnica convencional da cera perdida (n=10); G2) CAD/CAM (n=10); G3: CAD/CAM + Técnica da cera perdida (n=10). Uma matriz foi utilizada para simular uma prótese fixa implantossuportada de três elementos com um pôntico central. A infraestrutura do grupo G1 foi confeccionada em Ni-Cr, do grupo G2 em zircônia e G3 fresada em cera e fundida em Ni-Cr. Em todos os grupos a desadaptação marginal vertical e horizontal (subcontorno e sobrecontorno) foi avaliada através de um microscópio óptico tridimensional (Quick Scope, Mitutoyo). A revisão sistemática seguiu o critério PRISMA e está cadastrada na plataforma PROSPERO (CRD81865) e a busca foi realizada nas bases de dados Pubmed/MEDLINE, Embase and The Cochrane Library com artigos publicados até novembro de 2017. A questão PICO foi: "A técnica do ponto de solda contribui para uma melhor adaptação quando comparada a confecção em monobloco de infraestruturas e próteses fixas implantossuportadas?". O estudo in vitro demonstrou maior ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The aim of this study was to evaluate the marginal vertical, horizontal and internal misfit of implant-supported prostheses made through different techniques. In addition, to perform a systematic review and meta-analysis evaluating the effect of the welding technique on fixed prosthesis implants supported in make a better adaptation when compared the infrastructures made in one piece cast. A total of 30 infrastructures were made and divided into 3 groups: G1) Conventional- lost wax technique (n = 10); G2) CAD/CAM (n = 10); G3: CAD/CAM + lost wax technique (n = 10). A reference model was used to to simulate a 3-unit implant-supported fixed prostheses with a central pontic. In the G1 group the frameworks were made of Ni-Cr alloy, G2 group in zirconia and G3 milled in wax and fused in Ni-Cr alloy. In all groups, vertical and horizontal marginal misfit (under-contour and over-contour) was evaluated using a 3D optical microscope (Quick Scope, Mitutoyo, Japan). The systematic review and meta-analysis followed the PRISMA criteria and is registered on the PROSPERO (CRD81865). The search was performed in the Pubmed/MEDLINE, Embase and The Cochrane Library databases with selection of articles published until November 2017. The PICO question was: "The welding technique contributes to a better adaptation when compared to the one-piece cast frameworks of implant-supported prostheses?" The in vitro study showed a higher value of vertical marginal misfit for the G3 group (83.5μm), followed ... (Complete abstract click electronic access below)
Mestre
Duarte, Glauber Vieira. "Avaliação do exame radiográfico convencional e digital e digital no diagnóstico da adaptação entre implantes dentários e protéticos." Programa de Pós- Graduação em Odontologia da UFBA, 2007. http://www.repositorio.ufba.br/ri/handle/ri/11025.
Full textApproved for entry into archive by Rodrigo Meirelles(rodrigomei@ufba.br) on 2013-05-16T18:01:18Z (GMT) No. of bitstreams: 1 Dissertacao Glauber Duarte.pdf: 759281 bytes, checksum: 38271c0a48d32eb71858d76a5872d689 (MD5)
Made available in DSpace on 2013-05-16T18:01:18Z (GMT). No. of bitstreams: 1 Dissertacao Glauber Duarte.pdf: 759281 bytes, checksum: 38271c0a48d32eb71858d76a5872d689 (MD5) Previous issue date: 2007
A Implantologia é uma das modalidades de reabilitação bucal, inclusive pela alta taxa de sucesso das próteses implanto-suportadas. No entanto, estão sujeitas a alguns problemas exclusivos, como o afrouxamento do parafuso e a fratura do parafuso de fixação. A adaptação marginal de um pilar protético sobre o implante é imprescindível para que muitas destas falhas não ocorram. Além disso, desadaptações e cavidades entre estes componentes podem favorecer o acúmulo de bactérias e causar reações inflamatórias nos tecidos periimplantares. O estudo da adaptação marginal entre estes componentes faz parte de uma linha de pesquisa, com o objetivo de estabelecer um método diagnóstico padronizado, eficaz e reprodutível de avaliação. O presente estudo propôs-se a verificar a validade do método radiográfico convencional e sistema digital Digora, quanto à capacidade diagnóstica da adaptação marginal de cinco pilares protéticos, em titânio Procera Alltitan®, com diferentes aberturas entre o implante e o pilar protético. Os pilares foram aparafusados em um implante, que foi posteriormente fixado a uma base metálica hexagonal, permitindo a padronização das tomadas radiográficas e da avaliação microscópica. Os pilares foram avaliados quanto a sua adaptação no implante, utilizando um microscópio óptico comparador (Mitutoyo®), utilizado como padrão-ouro do estudo. Foram utilizados matrizes de poliéster em tiras com o intuito de obter aberturas marginais padronizadas de 50µm, 100µm, 150µm e 200µm, considerando que cada tira possui uma espessura de 50µm. Em cada sistema foram realizadas 75 tomadas radiográficas (15 de cada grupo de abertura marginal), obtendo imagens com cinco tipos de adaptação (adaptado, 50µm, 100µm, 150µm e 200µm). Deste modo, foram avaliados 150 pontos proximais, em cada sistema radiográfico. Dois radiologistas avaliaram as imagens e para a análise estatística foi utilizada uma matriz de decisões para a realização dos testes diagnósticos de: sensibilidade, especificidade, acurácia, valor preditivo positivo e negativo e a medida estatística Kappa. Os resultados obtidos indicaram que os sistemas radiográficos, convencional e digital, possuem alta sensibilidade, especificidade, acurácia, valores preditivos e bom nível de concordância com o grupo-ouro, com uma discreta, mas não relevante, redução da eficácia diagnóstica do sistema digital. Observou-se que os sistemas radiográficos avaliados são excelentes ferramentas de diagnóstico quando aberturas marginais maiores que 50µm não são aceitáveis. Deve-se considerar que o sistema radiográfico digital Digora® possui grandes vantagens sobre o sistema convencional, como a redução da dose de radiação, a eliminação de erros humanos durante o processamento e a economia de tempo. Deste modo, o sistema Digora pode ser incluído como uma ferramenta de grande importância na reabilitação protética sobre implantes.
Salvador