Дисертації з теми "Teeth Roots"
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1
Walker, Richard Thomas. "A comparative investigation of the root number and canal anatomy of permanent teeth in a Southern Chinese population." Thesis, [Hong Kong : University of Hong Kong], 1987. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12335423.
2
Wu, Andy Tzong Jong. "The extent of root resorption following the application of light (25g) and heavy (225g) controlled rotational orthodontic forces for 4 weeks: a micro-CT study." Thesis, The University of Sydney, 2009. https://hdl.handle.net/2123/28194.
Анотація:
In 1932 Beck and Marshall defined root resorption as the destruction of formed tooth
structure. Root resorption results in the loss of substance from dentine or cementum
and can present as either a physiological or pathological process. Physiological root
resorption can occur in both deciduous and permanent dentition. Root resorption of
the deciduous dentition is a normal and essential physiological process that facilitates
natural exfoliation. Pathological resorption is an inflammatory process that is
triggered by numerous factors.
Root resorption following orthodontic treatment is intimately associated with the
biological processes that occur during tooth movement. To date, the mechanism of
orthodontically induced inflammatory root resorption (henceforth referred to as
OIIRR) has not been fully understood. The pathological process is related to local
injury of the periodontal ligament associated with the removal of hyalinised tissue.
This process has been found to take place when local areas of the periodontal
ligament are overcompressed. The phenomenon is widely known as OIIRR and is
often unpredictable; it is an inevitable pathological consequence of orthodontic tooth
movement that compromises the success of orthodontic treatment.
The incidence of OIIRR ranges from 73% to 100% in recent studies} and its
prevalence has been shown to increase with orthodontic treatment. Experimental
research concludes that all human teeth develop resorption lacunae on the pressure
side of the root surface shortly after application of orthodontic forces.
3
Malek, Sameh. "Physical properties of human premolar cementum : a structural correlation." Thesis, The University of Sydney, 2000. http://hdl.handle.net/2123/4696.
4
Ngan, Daniel C. S. "The genetic contribution to orthodontic root resorption : a retrospective twin study." Thesis, The University of Sydney, 2003. http://hdl.handle.net/2123/4781.
5
Rizgar, Shahyan. "The Crisis of Identity in a Multicultural Society : A Multicultural Reading of Zadie Smith’s White Teeth." Thesis, Södertörns högskola, Institutionen för kultur och lärande, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-30710.
Анотація:
This essay, on Zadie Smith’s White Teeth, deals with the characters’ identities and the influences of multiculturalism on their complex identities. It also discusses the role of the characters roots and history in constructing their identities and how they have made life problematic for the characters in multicultural London. The roots and history of the first generation of immigrants make problematic identities for the second generation in the novel. The main aim of this essay is to demonstrate the instability of identity as depicted in the novel. The characters in the novel cannot ‘’plan’’ their identities because it is a process which continues in all stages of life. Though the first generation of immigrants want to ‘’plan’’ an identity for their children (the second generation of immigrants), they are not successful. Because identity is a process and it is changeable based on place and time. The second generation of immigrants, who live in London, tries to mix the dominant culture (English culture) with their familial culture in order to have a different identity. They also want to escape from their family’s roots and history but it is difficult, because leaving roots is not an easy process.
6
Dreyer, Craig William. "Clast cell activity in a model of aseptic root resorption." Title page, table of contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09phd778.pdf.
7
Mei, Lei, and 梅蕾. "Actions of chlorhexidine and silver diamine fluoride on cariogenic biofilm and root caries." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B44900776.
8
Soares, Paulo Vinicius. "Analise do complexo tensão-deformação e mecanismo de falha de pre-molares superiores com diferentes morfologias radiculares e redução sequencial de estrutura dental." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289706.
Анотація:
Orientador: Luis Roberto Marcondes MartinsTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Este trabalho tem avaliou o comportamento biomecânico de pré-molares superiores humanos por meio de análise da distribuição de tensões, deformação da estrutura dental e resistência à fratura, variando a morfologia radicular e o tipo de preparo cavitário. Foram selecionados 40 pré-molares superiores com dimensões coronárias semelhantes, distribuídos em 4 categorias de morfologia radicular diferentes (n=10): Uni - uniradiculares; FA - biradiculares com furca presente no terço apical da raiz; FM- biradiculares com furca presente no terço médio da raiz; FC - biradiculares com furca presente no terço cervical da raiz. Cada dente recebeu sete tipos seqüenciais de remoção de estrutura: H-hígido (controle), O- oclusal; OD- disto-oclusal, MOD- mésio-ocluso-distal, MOD+Aacesso endodôntico, TE- tratamento endodôntico e RC- restauração com resina composta. O comportamento biomecânico dos dentes foi analisado de forma comparativa entre diferentes metodologias: 1) simulação computacional para análise da distribuição de tensões (método de elementos finitos), 2) ensaio laboratorial não-destrutivo para análise das deformações (método de extensometria) e 3) ensaio laboratorial destrutivo para análise da resistência a fratura (método de resistência à fratura), além da realização da classificação do padrão de fratura. Observou-se que a remoção de estrutura dental favoreceu maior acúmulo de tensões e deformação. O tipo de morfologia radicular influenciou no padrão de deformação de cúspide e face proximal, sendo a furca cervical o fator mais importante no aumento dos valores de deformação. A furca presente no terço cervical e sulcos profundos das faces proximais promoveram maior incidência de fraturas severas. Observou-se também correlação direta dos resultados encontrados nos diferentes métodos empregados.
Abstract: The aim of this work was to evaluate the biomechanical behavior of restored maxillary human premolar throughout stress-strain, stress distribtion analysis and fracture resistance with different root morphologies and the cavity preparation design. Forty maxillary premolars with similar coronary dimensions were selected and divided into 4 morphology categories (n=10): Uni- single rooted; Fabiradicular premolar with apical furcation; FM- biradicular premolar with medium furcation; FC- biradicular premolar with cervical furcation. Each tooth received seven treatments with structural reduction: H- sound tooth (control group), Ooclusal cavity; OD- disto-occlusal cavity; MOD- mesio-occlusal-distal cavity; MOD+A- endodontic access; TE- endodontic tretment; RC- restoration with composite resin. The biomechanical behavior of the teeth was analyzed by methodologies association: 1)Finite Element Analysis, 2) Strain-gauge method and 3) Fracture resistance test and Failure mode), and was made the fracture mode classification. It was observed that dental structure loss promotes high stress concentration inside the teeth and cuspal deflection. The root morphology influenced cusp and proximal surface strain. The cervical furcation was the main factor of strain data increase. This study showed that the association of different methodologies is an important tool for biomechanical analysis.
Doutorado
Dentística
Doutor em Clínica Odontológica
9
Carey, Helen. "Debridement Of Subgingival Periodontally Involved Root Surfaces With A Micro-Applicator Brush: A Macroscopic And Scanning Electron Microscope Study." University of Sydney, 1998. http://hdl.handle.net/2123/4957.
Анотація:
Master of Science in DentistryThis work was digitised and made available on open access by the University of Sydney, Faculty of Dentistry and Sydney eScholarship . It may only be used for the purposes of research and study. Where possible, the Faculty will try to notify the author of this work. If you have any inquiries or issues regarding this work being made available please contact the Sydney eScholarship Repository Coordinator - ses@library.usyd.edu.au
10
Cavassim, Rodrigo [UNESP]. "Avaliação da descontaminação com ácido cítrico e tetraciclina e da rugosidade, na adesão de coágulo a superfícies radiculares submetidas a diferentes tipos de instrumentação." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/104726.
Анотація:
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O tratamento periodontal engloba o processo de raspagem e alisamento radicular, podendo ser realizado por diferentes meios que além de remover o cálculo dental, produzem diferentes características na superfície radicular como ranhuras e concavidades e também a formação de smear layer. O uso de agentes químicos é proposto na literatura para remover essa smear layer, e descontaminar a superfície radicular, aumentando assim as chances de formação de nova inserção conjuntiva. O objetivo do Estudo 1 foi avaliar, por meio de microscopia eletrônica de varredura, a influência de diferentes concentrações, modos e tempos de aplicação de ácido cítrico na biomodificação de superfícies radiculares submetidas à raspagem e alisamento radicular. Neste estudo, 270 amostras foram divididas em 6 grupos (45 amostras/grupo): soro fisiológico (controle), ácido cítrico (0.5%, 1%, 2%, 15% e 25%), com tempos de 1, 2 ou 3 minutos para cada grupo, nos modos de aplicação: a) aplicação passiva (bolinha de algodão); b) fricção suave (pincel); c) fricção vigorosa (bolinha de algodão), com renovação da solução a cada 30 segundos. As amostras foram submetidas à desidratação em concentrações crescentes de álcool etílico e HMDS, sendo em seguidas metalizadas e levadas para observação em microscopia eletrônica de varredura. Um examinador treinado, calibrado (kappa=0,93) e cego avaliou as fotomicrografias obtidas. A análise estatística foi realizada utilizando-se os testes de Kruskal- Wallis e Dunn. No estudo 2, investigou-se a influência da biomodificação radicular associada a diferentes meios de instrumentação na adesão de coágulo e elementos sanguíneos. Cento e cinquenta dentes afetados periodontalmente foram divididos em 5 grupos: Grupo I, instrumentação com curetas; Grupo II, instrumentação com curetas removendo cálculo superficial; Grupo III, remoção...
Periodontal treatment encompasses the scaling and root planning process and can therefore be carried out by various means. In addition to removing dental calculus, the root instrumentation produces different characteristics in the radicular surface as the formation of concavities and smear layer. The use of chemical agents is proposed in the literature to remove the smear layer, and detoxify the radicular surface, thereby increasing the chances of forming new connective attachment. The aim of the Study 1 was to assess, through scanning electron microscopy, the influence of different concentrations, application methods and application times of citric acid in the root conditioning after scaling and root planning. Two hundred seventy (270) samples were equally divided into six groups (n=45) for treatment with saline solution (control) and five different concentrations of citric acid (0.5, 1, 2, 15, and 25 percent). Three acid application methods were used (passive, brushing, and burnishing) as well as three application periods (1, 2, and 3 minutes). A previously trained, calibrated (kappa score = 0.93), and blind examiner subsequently scored scanning electron micrographs (SEMs) of the samples. Statistical analyses were performed by using Kruskal-Wallis and Dunn’s post-hoc tests. In Study 2, was investigated the influence of root conditioning associated with different modes of instrumentation in the adhesion of clot and blood elements. One hundred and fifty periodontally affected teeth were divided into five groups: Group I, instrumentation with curettes; Group II, instrumentation with curettes removing the superficial calculus; Group III, ultrasonic scaler with removal of the superficial calculus; Group IV, ultrasonic scaler for removal of the superficial calculus and after that, instrumentation with curettes; Group V, calculus surface. These five groups were further divided... (Complete abstract click electronic access below)
11
Rambo, Marcos Vinicio Haas. "Estudo in vivo da impedância do canal radicular dentário em função da frequência." Universidade Tecnológica Federal do Paraná, 2012. http://repositorio.utfpr.edu.br/jspui/handle/1/343.
Анотація:
Localizadores eletrônicos do forame (LEF) estão conquistando cada vez mais espaço na terapia endodôntica para a determinação do comprimento de trabalho (CT). O CT delimita a profundidade que os instrumentos devem alcançar durante o tratamento do canal, e sua correta determinação é um ponto chave para o sucesso da terapia endodôntica. O método radiográfico é tradicionalmente utilizado nessa etapa cirúrgica, mas os métodos eletrônicos têm se mostrado mais rápidos, precisos e seguros. Diversos métodos eletrônicos têm sido propostos e estudos foram publicados com o objetivo de avaliar a exatidão destes aparelhos na determinação do CT. Pesquisas também foram conduzidas com o objetivo de avaliar a impedância entre os eletrodos de teste utilizados pelos LEFs: a lima endodôntica e o eletrodo fixado na membrana mucosa oral. No entanto, a literatura ainda é carente de estudos in vivo da impedância do canal radicular dentário. A presente monografia tenta preencher esta lacuna com a apresentação de resultados de estudos realizados para a avaliação in vivo da impedância do canal radicular dentário. Os resultados obtidos nestes estudos foram usados para modelar a resposta em frequência da impedância do canal da raiz do dente e para encontrar circuitos equivalentes que representem a inclinação desta resposta em escala logarítmica. Eles também serviram de base para o desenvolvimento de um LEF inovador baseado em um novo parâmetro de medida, o qual foi denominado coeficiente da atenuação espectral da impedância do canal radicular dentário. O protótipo desenvolvido para os experimentos in vivo possibilitou ainda a realização de um estudo inédito sobre o método da razão, que é uma das técnicas eletrônicas utilizada para a localização do forame apical.Electronic foramen locators are becoming more popular in the endodontic therapy for the determination of the working length. The working length delimits the deepest point in the root canal that instruments may reach during root canal treatment, and its accurate determination is a key factor for the success of endodontic therapy. The radiographic method is traditionally used in this surgical step, but electronic methods have proved to be faster, more precise and safer. Several electronic methods have been proposed and studies assessing the accuracy of these devices were published. The evaluation of the impedance between the two test probes used by the electronic devices, the endodontic file and the hook shape electrode that is attached to the oral mucosa membrane, has also been the subject of several studies. However, there is a lack of in vivo evaluations of the root canal impedance in the literature. The present work tries to fulfill this gap with in vivo investigative studies of the root canal impedance. The results of these studies were used to model the frequency response of the root canal impedance and to find equivalent circuits that represent the inclination of the frequency response in logarithmic scale. They were also employed in the development of an innovative electronic foramen locator based on the spectral attenuation coefficient of the root canal impedance. With the prototype used in the in vivo characterization of the root canal impedance, another study was conducted to assess the ratio method, which is one of the electronic techniques used to locate the apical foramen.
12
Cavassim, Rodrigo. "Avaliação da descontaminação com ácido cítrico e tetraciclina e da rugosidade, na adesão de coágulo a superfícies radiculares submetidas a diferentes tipos de instrumentação /." Araraquara : [s.n.], 2012. http://hdl.handle.net/11449/104726.
Анотація:
Orientador: José Eduardo Cezar SampaioBanca: Juliana Rico Pires
Banca: Fábio André dos Santos
Banca: Rosemary Adriana Chierici Marcantonio
Banca: Carlos Rossa Junior
Resumo: O tratamento periodontal engloba o processo de raspagem e alisamento radicular, podendo ser realizado por diferentes meios que além de remover o cálculo dental, produzem diferentes características na superfície radicular como ranhuras e concavidades e também a formação de smear layer. O uso de agentes químicos é proposto na literatura para remover essa smear layer, e descontaminar a superfície radicular, aumentando assim as chances de formação de nova inserção conjuntiva. O objetivo do Estudo 1 foi avaliar, por meio de microscopia eletrônica de varredura, a influência de diferentes concentrações, modos e tempos de aplicação de ácido cítrico na biomodificação de superfícies radiculares submetidas à raspagem e alisamento radicular. Neste estudo, 270 amostras foram divididas em 6 grupos (45 amostras/grupo): soro fisiológico (controle), ácido cítrico (0.5%, 1%, 2%, 15% e 25%), com tempos de 1, 2 ou 3 minutos para cada grupo, nos modos de aplicação: a) aplicação passiva (bolinha de algodão); b) fricção suave (pincel); c) fricção vigorosa (bolinha de algodão), com renovação da solução a cada 30 segundos. As amostras foram submetidas à desidratação em concentrações crescentes de álcool etílico e HMDS, sendo em seguidas metalizadas e levadas para observação em microscopia eletrônica de varredura. Um examinador treinado, calibrado (kappa=0,93) e cego avaliou as fotomicrografias obtidas. A análise estatística foi realizada utilizando-se os testes de Kruskal- Wallis e Dunn. No estudo 2, investigou-se a influência da biomodificação radicular associada a diferentes meios de instrumentação na adesão de coágulo e elementos sanguíneos. Cento e cinquenta dentes afetados periodontalmente foram divididos em 5 grupos: Grupo I, instrumentação com curetas; Grupo II, instrumentação com curetas removendo cálculo superficial; Grupo III, remoção... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Periodontal treatment encompasses the scaling and root planning process and can therefore be carried out by various means. In addition to removing dental calculus, the root instrumentation produces different characteristics in the radicular surface as the formation of concavities and smear layer. The use of chemical agents is proposed in the literature to remove the smear layer, and detoxify the radicular surface, thereby increasing the chances of forming new connective attachment. The aim of the Study 1 was to assess, through scanning electron microscopy, the influence of different concentrations, application methods and application times of citric acid in the root conditioning after scaling and root planning. Two hundred seventy (270) samples were equally divided into six groups (n=45) for treatment with saline solution (control) and five different concentrations of citric acid (0.5, 1, 2, 15, and 25 percent). Three acid application methods were used (passive, brushing, and burnishing) as well as three application periods (1, 2, and 3 minutes). A previously trained, calibrated (kappa score = 0.93), and blind examiner subsequently scored scanning electron micrographs (SEMs) of the samples. Statistical analyses were performed by using Kruskal-Wallis and Dunn's post-hoc tests. In Study 2, was investigated the influence of root conditioning associated with different modes of instrumentation in the adhesion of clot and blood elements. One hundred and fifty periodontally affected teeth were divided into five groups: Group I, instrumentation with curettes; Group II, instrumentation with curettes removing the superficial calculus; Group III, ultrasonic scaler with removal of the superficial calculus; Group IV, ultrasonic scaler for removal of the superficial calculus and after that, instrumentation with curettes; Group V, calculus surface. These five groups were further divided... (Complete abstract click electronic access below)
Doutor
13
Ribeiro, Erica Del Peloso. "Iodo povidine associado a instrumentação periodontal no tratamento de lesões de bifurcação : avaliações clinica e bioquimica." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287918.
Анотація:
Orientadores: Marcio Zaffalon Casati, Sergio de ToledoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O objetivo do presente estudo foi avaliar a ação de uma solução de iodo povidine (PVP-I), associada à raspagem e alisamento radicular, no tratamento de lesões de bifurcação. Foram selecionados 44 pacientes com pelo menos um molar com lesão de bifurcação classe II, em face livre, profundidade de sondagem ³ 5 mm e sangramento à sondagem. Os pacientes foram divididos aleatoriamente em 2 grupos: grupo controle - raspagem e alisamento radicular com ultra-som e água destilada como solução refrigerante; grupo teste - raspagem e alisamento radicular com ultra-som e PVP-I 10% como solução refrigerante. Foram avaliados os seguintes parâmetros clínicos: índice de placa (IP), sangramento à sondagem (SS), posição da margem gengival (PMG), nível clínico de inserção relativo (NICr), profundidade de sondagem (PS) e nível clínico de inserção horizontal relativo (NICHr). A avaliação bioquímica da atividade de enzimas tipo tripsina no biofilme subgengival foi feita pelo teste BAPNA. Os parâmetros descritos acima foram avaliados antes do tratamento, 1, 3 e 6 meses após. Ambos os grupos apresentaram médias semelhantes de redução da PS, ganho de NICr e de NICHr. Aos 6 meses, esses valores foram, respectivamente, 2,31 mm, 1,17 mm e 1,00 mm no grupo controle e 2,31 mm, 1,23 mm e 1,02 mm no grupo teste (p>0,05). Diferença estatisticamente significante também não foi observada entre os grupos quanto ao número de sítios que ganharam 2 mm ou mais de inserção. Aos 6 meses, os grupos controle e teste apresentaram, respectivamente, 45,16% e 30,77% das áreas com ganho de inserção = 2 mm. Na comparação entre os grupos quanto ao SS das lesões de bifurcação aos 6 meses e à quantidade de áreas que exigiram retratamento no 3° mês foi encontrado p=0,06, favorecendo o grupo teste. O teste BAPNA não detectou diferença entre os grupos, entretanto, foi observada diferença intra-grupo, indicando redução na atividade de enzimas do tipo tripsina. Pôde-se concluir que o PVP-I, usado como adjunto da instrumentação periodontal traz benefícios clinicamente significantes ao tratamento de lesões de bifurcação classe II, em faces livres
Abstract: The aim of this randomized single-blind controlled clinical trial was to evaluate the effect of topically applied povidone-iodine (PVP-I), used as an adjunct to non-surgical therapy of furcation involvements. Forty-four patients presenting at least one class II furcation involvement that bled on probing, in bucal or lingual surfaces, with probing pocket depth ³ 5 mm were recruited. Patients were stratified into 2 treatment groups: subgingival instrumentation by an ultrasonic device using PVP-I (10%) as the cooling liquid (test group); identical treatment using distilled water as the cooling liquid (control group). The following clinical outcomes were evaluated: plaque index, bleeding on probing (BOP), position of the gingival margin, relative attachment level (RAL), probing pocket depth (PPD) and relative horizontal attachment level (RHAL). BAPNA test was used to analysis the trypsin-like activity in dental biofilm. The clinical and biochemical parameters were evaluated at baseline and 1, 3 and 6 months after therapy. Both groups had similar means of PPD reduction and RAL and RHAL gain. At 6 months, these variables were, respectively, 2.31 mm, 1.17 mm and 1.00 mm in the control group and 2.31 mm, 1.23 mm and 1.02 mm in the test group (p<0.05). No differences were observed in terms of the frequency distribution of sites demonstrating RAL gain ³ 2 mm. The comparison between groups on BOP of the furcation sites, at 6 months and on the number of sites referred for re-treatment at 3 months showed better values in the test group (p=0.06). The results of BAPNA test failed to demonstrate significant differences between groups. The use of topically applied PVP-I with subgingival instrumentation may provide additional clinical significant benefits to the treatment of class II furcation involvements
Mestrado
Periodontia
Mestre em Clínica Odontológica
14
Zhang, Wen, and 張文. "A randomized controlled clinical trial of oral health promotion strategies to prevent and arrest root caries among Hong Kong'seldering." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43278498.
15
Novais, Veridiana Resende. "Análise mecânica de retentores intra-radiculares." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290499.
Анотація:
Orientador: Carlos José SoaresTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Este estudo avaliou os aspectos mecânicos de retentores intra-radiculares pré-fabricados reforçados com fibra, de forma progressiva por meio de etapas distintas e seqüenciais, divididas em três experimentos. No Capítulo 1, foram avaliados parâmetros como: efeito da conicidade do pino, distância entre os suportes, e propriedades dos pinos na flexão e tensão máxima pelo método de elementos finitos na realização de ensaios de flexão de 3 pontos. Foi gerado modelo tri-dimensional de pino de fibra de vidro (RelyX post, 3M-Espe), variando posições dos suportes inferiores e inclinação do pino. Empregou-se propriedades elásticas, características ortotrópicas e isotrópicas. A inclinação dos pinos cônicos para nivelá-los nos suportes teve pouco efeito nas tensões. A flexão aumentou quando 50% da porção carregada do pino envolveu conicidade. Quando o posicionamento do pino envolveu 20% da porção cônica, os valores de flexão foram similares ao modelo de referência, que é o pino cilíndrico, sem inclinação. Propriedades ortotrópicas resultaram em aumento da flexão comparado ao pino isotrópico. No Capítulo 2, propriedades mecânicas de diferentes sistemas de pinos pré-fabricados foram avaliadas por ensaio experimental de flexão de três pontos, assim como análise da correlação entre propriedades mecânicas e características estruturais visualizadas por microscopia eletrônica de varredura associado à software de processamento de imagens. Os resultados demonstraram que as características estruturais afetaram significativamente as propriedades mecânicas dos pinos. Resistência à flexão está diretamente correlacionada com a razão fibra/matriz de resina, enquanto módulo de flexão está inversamente relacionado ao número de fibras/mm2. No Capítulo 3, foi avaliada resistência de união de pino de fibra ao núcleo de preenchimento de resina composta por meio do teste de push-out, variando o tipo de agente silano: três silanos pré-hidrolizados e um sistema de silano de dois componentes; e a temperatura de secagem com ar após aplicação do silano: 23°C e 60°C. Empregou-se ainda grupo controle negativo, no qual nenhum tratamento do pino foi realizado. A aplicação de silano pré-hidrolizado e secagem com ar quente (60°C) dos pinos não influenciou a resistência de união. O agente silano de dois componentes com temperatura de secagem de 23°C apresentou os maiores valores de resistência de união. Desta forma, dentro das limitações dos três experimentos, conclui-se que teste de flexão de três pontos empregado para avaliação de pinos pré-fabricados é válido quando limita a área de ensaio à porção cilíndrica dos pinos; as características estruturais dos pinos têm correlação com as propriedades mecânicas dos mesmos; e a aplicação de ar quente sobre as superfícies de pinos silanizados não tem efeito significativo na resistência de união entre pinos de fibra e preenchimento com resina composta
Abstract: The fiber-reinforcement composite (FRC) posts introduced the new concept of restorative system, in which the various components of the reconstruction: post, cement, filling material and dentin have now become a complex mechanically homogeneous. The knowledge of the structure, composition and physical properties of these fiber posts systems is important in order to minimize the failures and the unsuccessfully clinical. Thus, the present study was conducted to analyze sequentially the biomechanical parameters of FRC posts through different stages divided into three experiments. In Chapter 1, the effect of taper, specimen supports and the properties on flexure and stress response during three-point bending were analyzed using finite element analysis. Three-dimensional non-linear finite element model of a fiber-reinforced composite post was created. Different support positions were evaluated during a simulated three-point bending test. The applied properties were elastic and orthotropic. Tilting the tapered posts to level those in the test setup had little effect on the outcome. Flexure increased when 50% of the bent portion involved taper. If 20% of the bent post involved taper, the flexure values were close to control group. The orthotropic properties also resulted in increased flexure compared to an isotropic post. Maximum stresses were only a little higher when 50% of the bend structure involved taper, while the orthotropic properties had little effect. In Chapter 2, the mechanical properties of different FRC posts were assessed with three-point bending test and evaluated the correlation between mechanical properties and structural characteristics by scanning electron microscopy (SEM) associated with an software of image processing. Then, the structural characteristics significantly affect the mechanical properties of fiber posts. The flexural strength is directly correlated with fiber/matrix ratio, whereas the flexural modulus is inversely correlated with number of fibers per mm2 of post. In the Chapter 3, was evaluate the effect of three prehydrolyzed silanes and one two-bottle coupling agent and two air-drying temperature (23°C and 60°C) on the bond strength between glass fiber posts and composite resin core using micropush-out testing. Additionally, it was tested a control group, which no treatment of fiber post were realized. The results showed that drying with warm air and post silanization with pre-hydrolized silanes had no significant effect on push-out bond strength between glass fiber post and composite resin core. For 23°C air-drying groups, the bond strength with two-bottle coupling agent was higher than the other groups. Then, based on the findings of this study, and within the limitation of this investigation, could be concluded that the regardless of leveling, the flexural stress determination with tapered fiber-reinforced posts in the three-point bending test was valid as long as the tapered portion was limited. Additionally, the mechanical properties have correlation with structural characteristics of FRC posts. Finally, the warm air-drying in silanizated post surface had not significant effect on bond strength between fiber post and composite resin core
Doutorado
Materiais Dentarios
Doutor em Materiais Dentários
16
Caiado, Ana Carolina Rocha Lima. "Resistencia de união e caracterização morfologica da dentina coronaria e radicular tratada com sistemas adesivos." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288182.
Анотація:
Orientador: Mario Fernando de GoesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Este estudo teve como objetivos: (a) caracterizar a morfologia, a densidade e a área transversal de túbulos dentinários da dentina coronária (profunda) e radicular (terço cervical) intactas e após condicionamento com ácido fosfórico 32% (AF) e primer condicionante do sistema adesivo Clearfill Protect Bond (P); e (b) avaliar e comparar a resistência de união e os padrões de fratura obtidos na dentina coronária (profunda) e dentina radicular (terço cervical). Pré-molares humanos hÃgidos foram fixados em gluteraldeÃdo (2,5%). Secções da dentina coronária profunda e dentina radicular (região cervical) foram obtidas por clivagem. Cada dente recebeu os seguintes tratamentos: G1- dentina coronária + AF; G2- dentina coronária + P; G3 - dentina coronária sem tratamento; G4- dentina radicular + AF; G5- dentina radicular + P; G6- dentina radicular sem tratamento. As secções condicionadas com primer foram imersas em etanol e acetona. Todos os grupos foram desidratados em concentrações ascendentes de álcool e HMDS e visualizadas por microscopia eletrÃ'nica de varredura em ampliação de 1500X. As imagens obtidas foram usadas para calcular a densidade (D) e a área (A) da secção transversal dos túbulos dentinários em µm2 utilizando o programa Leica IM50. Para o teste de microtração foram utilizados fatias de dentina coronária profunda e dentina radicular cervical de 12 dentes que foram divididas em quatro grupos de acordo com a região dentinária e o sistema adesivo utilizado: G7- dentina radicular + Single Bond II; G8- dentina radicular + Clearfill Protect Bond; G9- dentina coronária + Single Bond II; G10- dentina coronária + Clearfill Protect Bond. Resina composta foi acrescentada em ambos os lados das fatias. Foram obtidas dessas fatias espécimes em forma de palito. Após armazenamento em água (37ºC) os espécimes foram submetidos ao teste de microtração em uma máquina de ensaio universal (Instron), a uma velocidade de 0,5mm/min. A dentina radicular intacta do terço cervical apresentou uma superfÃcie irregular formada por calcosferitos, o que a difere estruturalmente da dentina coronária. Já a densidade (42.627/mm2) e a área transversal média (2,9035/ µm2) dos túbulos dentinários na raiz não revelou diferença estatisticamente significante (p> 0,05) aos valores encontrados na coroa. Os dados de resistência de união foram estatisticamente superiores na dentina coronária (26.63 MPa) do que na dentina radicular (19.76 MPa). O padrão de fratura mais frequentemente encontrado para ambas as regiões foi a fratura mista (coesiva no adesivo e na camada hÃbrida). ÿ possÃvel concluir que as dentinas coronária (profunda) e radicular do (terço cervical) apresentam diferenças morfológicas e nos valores de resistência de união, porém apresentam semelhanças quanto à densidade de túbulos e padrões de fratura independente do sistema adesivo utilizado
Abstract: The aim of this study was to: (a) characterize the morphology, density and transversal cross-section area of tubules of deep crown and cervical root dentine, intact and after etched with 32% phosphoric acid (AF) or the self-etch primer of the Clearfill Protect Bond adhesive system (P); and (b) evaluate and compare the bond strength and the fracture patterns obtained from deep crown dentine and cervical root dentine. Human carie-free premolars (n=5) were fixed in 25% glutaraldehyde. Deep crown and root dentine sections were obtained by cleavage. Each tooth was treated as follows: G1- crown dentine + AF; G2- crown dentine and P; G3-intact crown dentine; G4- root dentine + AF; G5- root dentine + P; G6- intact root dentine. The sections etched with primer were immersed in ethanol and acetone. All groups were dehydrated in increasing alcohol concentration and Hexamethyldisilazane, nd were visualized by Scanning Electron Microscopy. A magnification of 1500X was used to calculate the density (D) and the dentinal tubule transversal cross-section area per mm2, using the program Leica IM50. For microtensile testing, twelve premolars were cut to obtain slices of deep crown dentine and cervical root dentine. These were divided in four groups according to dentine region and adhesive system employed: G7- root dentine + Single Bond II; G8- root dentine + Clearfill Protect Bond; G9- crown dentine + Single Bond II; G10- crown dentine + Clearfill Protect Bond. Restorative was added to both sides of the slices. Beam specimens were obtained from these restored slices which were kept in water at 37ºC. The specimens were microtensile tested using a universal testing machine (Instrom) at a speed of 0,5mm/min. Intact cervical root dentine presented an irregular surface formed with calcospherites, demonstrating its structural difference from coronary dentine. On the other hand, root dentine tubule density (42,627/mm2) and average transversal area (2.9035/ µm2) did not reveal statistically significant difference (p>0.05) when compared to values obtain in crown. Bond strength results were statistically superior for crown dentine (26.63 MPa) then root dentine (19.76 MPa). Mixed fractures (cohesive in adhesive and hybrid layer) were the most frequent fracture patterns found for both regions. It is possible to conclude that deep crown dentine and cervical root dentine present morphological and bond strength differences, however, are similar in relation to tubule density and fracture patterns independent of the adhesive system employed.
Mestrado
Endodontia
Mestre em Clínica Odontológica
17
Dahlstrom, Stephen W. "Hydroxyl radical activity in bleached root-filled teeth /." Title page, contents and summary only, 1992. http://web4.library.adelaide.edu.au/theses/09DM/09dmd131.pdf.
18
Byström, Anders. "Evaluation of endodontic treatment of teeth with apical periodontitis." Umeå : [University of Umeå], 1986. http://catalog.hathitrust.org/api/volumes/oclc/15239472.html.
19
Roy, Rajneesh, and n/a. "Theory and practice of resecting and managing root ends." University of Otago. School of Dentistry, 2007. http://adt.otago.ac.nz./public/adt-NZDU20071221.144604.
Анотація:
Contemporary methods of resection and management of the root end during apical surgery were reviewed. Two studies are reported here, one on the amount of peripheral root structure remaining after root-end cavity preparation in maxillary central incisors and canines, and the other on the effect of the dimensions of the cut root face on the size of the root-end cavities cut by experienced endodontists.
To investigate the amount of peripheral root structure remaining after root-end cavity preparation, three senior endodontic graduate students were asked to prepare conservative root-end cavities in thirty root-treated maxillary central incisors and thirty canines. Not a single tooth had the recommended 2 mm circumferential root dentine after 3 mm resection. Sixty two percent of the central incisors did not have a 2 mm dentine periphery around the root-end cavity preparations after 6 mm resection.
To investigate the effect of the dimensions of the cut root face on the size of root-end cavities, five practicing endodontic specialists prepared conservative root-end cavities in thirty single-rooted teeth each after resection of the apical 3 mm. The endodontists prepared larger cavities in larger root faces. More precisely, the cavity sizes suggested that the endodontists were suffering from the effects of a visual illusion, the Delboeuf illusion.
There are two major conclusions. First, the theory concerning the amount of circumferential dentine in a resected root face needs revision. Second, endodontists need to be aware of how the appearance of a cut root face can influence the size of cavities they cut.
20
Sathorn, Chankhrit. "Factors affecting fracture susceptibility of tooth root : a laboratory and finite element analysis (FEA) study /." Connect to thesis, 2004. http://eprints.unimelb.edu.au/archive/00001600.
21
Thomas, Robyn Patricia. "Root canal morphology of maxillary permanent first molar teeth at various ages." Thesis, The University of Sydney, 1986. http://hdl.handle.net/2123/4668.
22
Davey, Alan Lintern. "A transmission electron microscopic and autoradiographic study of Hertwig's root sheath initiation /." Title page, contents and summary only, 1986. http://web4.library.adelaide.edu.au/theses/09DM/09dmd248.pdf.
23
Hsieh, Hsin-Ju. "A case series study of Vitapex® pulpectomy treatment in primary teeth II." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2007. https://www.mhsl.uab.edu/dt/2007m/hsieh.pdf.
24
Chan, Tak-kam. "Clinical and radiographic evaluation of root canal treated teeth 10 to 20 years after treatment." Click to view the E-thesis via HKUTO, 2001. http://sunzi.lib.hku.hk/HKUTO/record/B38628089.
25
陳德錦 and Tak-kam Chan. "Clinical and radiographic evaluation of root canal treated teeth 10 to20 years after treatment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B38628089.
26
Mashaly, Ayat Mohamed Maged Mofid Ahmed. "Fracture resistance of different intra-canal systems for restoring primary anterior teeth in vitro study /." Thesis, Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B44173398.
27
Garden, Laura T. "Potential Antimicrobial Methods for Provisionalizing Teeth After Endodontic Treatment." VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5334.
Анотація:
POTENTIAL ANTIMICROBIAL METHODS FOR PROVISIONALIZING TEETH AFTER ENDODONTIC TREATMENT
By Laura T. Garden, DDS
A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Dentistry at Virginia Commonwealth University.
Virginia Commonwealth University, 2018
Thesis Advisor: Garry Myers, DDS
Department of Endodontics
Objective:To evaluate the effectiveness of a Chlorhexidine soaked cotton pellet on bacterial leakage.
Methods: Fifty-one extracted teeth, including six controls, were instrumented, obturated, and sealed with either a cotton pellet (CP), 2% Chlorhexidine soaked cotton pellet (CHX), or a Permaflo orifice barrier (OB). Each root was suspended between two chambers: the coronal chamber inoculated with brain heart infusion broth and colony-forming units of Enterococcus faecalis, the apical chamber with brain heart infusion broth and phenol red. The latter was checked daily for turbidity, indicating bacterial leakage.
Results: All open and closed control groups had leaked by day 7. The average CP tooth survived for 13.1 days whereas the CHX and OB teeth leaked by an average of 5.8 days.
Conclusion:There is insufficient evidence to support the use of a Chlorhexidine soaked cotton pellet. The results were not as expected and the study design should be re-evaluated.
28
Zaghwan, Ala M. H. "Quality of root filling by three different techniques in teeth after minimal root canal preparation and the GentleWave cleaning." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/58573.
Анотація:
Objective: This study aimed to examine the quality of root filling in canals obturated using three different filling techniques after minimal root canal preparation and GentleWave (GW) cleaning.
Methods: Root canals of 30 mandibular molars were instrumented to size 20/.04 taper using hand K-files, and a Vortex Blue NiTi rotary file. Sodium hypochlorite (NaOCl) 6% was used in-between each instrument insertion and the canals were finally cleaned using a 7.5 min irrigation by the GW. The samples were scanned with micro-CT using a voxel size of 30 µm after instrumentation (pre-GW), post-GW, and after obturation. The samples were randomly allocated into three groups (n = 10) with regard to the root filling method: (1) single-cone with AH Plus sealer (SC/AH+), (2) single-cone with GuttaFlow sealer (SC/GF), and (3) GuttaCore with AH Plus sealer (GC/AH+). The reconstructed 3D images were analyzed for the volumetric percentages of debris, filling materials, gaps, and voids at three canal levels. Data was analyzed statistically using Kruskal-Wallis and Mann-Whitney U tests. P values < 0.05 were considered to be significant.
Results: The proportion (volume %) gaps and voids proportions in multi-rooted canals obturated by using GC/AH+ and SC/GF was significantly lower than in canals filled with SC/AH+ (P = 0.000). Different values indicated a statistical difference between coronal, middle and apical gaps and voids volumes within each group. The mean volumes of coronal and middle gaps and voids were significantly different from the mean volume of apical gaps and voids in canals filled with SC/GF (P = 0.000), (P = 0.001). The quality of mesial fillings did not differ statistically from the distal fillings amongst the three groups. After conventional irrigation, 4.58 % of canal volumes was filled with debris while no debris was found after GW cleaning.
Conclusion: A high quality of filling was achieved by GC/AH+ and SC/GF indicating that both these methods are suitable to fill the minimally instrumented root canals after GentleWave cleaning.Dentistry, Faculty of
Graduate
29
Saunders, Elizabeth M. "In vitro and in vivo investigations into root canal obturation using thermally softened gutta percha techniques." Thesis, University of Dundee, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292861.
30
Sanders, Aaron Anthony. "An Experimental Investigation of the Influence of Elliptical Root Shapes and Asymmetric Teeth on Root Stresses and Bending Fatigue Lives." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1290530501.
31
Warren, Nichola. "In vitro Infection and Disinfection of Dentinal Tubules in Human Teeth." Diss., University of Pretoria, 2013. http://hdl.handle.net/2263/31619.
Анотація:
Introduction: Bacteria are the most common pathogens responsible for pulpal necrosis and periapical disease conditions. The importance of eradicating bacteria and their endotoxic by-products has been highlighted in numerous studies. Aim: The aim of this in vitro study was to establish the efficacy of six endodontic disinfection protocols in eradicating Enterococcus faecalis from single root canals of human teeth. Materials and Methods: Endodontic access cavities were prepared on 86, extracted, single rooted, human teeth. Root canal preparation was done using nickel titanium rotary files. Each tooth was sterilised, inoculated with E. faecalis and randomly allocated to one of seven groups (n = 12). The six disinfection protocols were 3% sodium hypochlorite solution (NaOCl), 2% chlorhexidine digluconate solution (CHX), Chlor-XTRA, 3% NaOCl combined with 2% CHX, 3% NaOCl followed by photo-activated disinfection (PAD) and PAD alone. The seventh group was irrigated with sterile water (control). The roots were fractured longitudinally. Dentine samples from coronal, middle and apical sections of one half of each root were plated onto brain heart infusion (BHI) plates. These were incubated anaerobically at 37⁰C for five days. The colony-forming units (cfu) were counted. The second half of each root was prepared for Scanning Electron Microscopy. The Pairwise Wilcoxon Rank Sum test and the Kruskal-Wallis test were used to compare the cfu counts of the seven groups to one another. Results: Two per cent CHX, Chlor-XTRA, combination of 3% NaOCl and 2% CHX and irrigation with 3% NaOCl followed by PAD were able to eradicate E. faecalis from the coronal levels of the root canals. A combination of 3% NaOCl and 2% CHX and irrigation with 3% NaOCl followed by PAD were able to eradicate E. faecalis from the middle levels of the root canals. None of the disinfection protocols were able to eradicate E. faecalis from the apical levels of all root canals. The regimen of 3% NaOCl followed by 2% CHX was slightly more efficient in eradicating E. faecalis from the root canals than the other disinfection regimens. Dentine erosion and precipitate formation were two incidental observations in some of the samples upon SEM examination.Dissertation (MSc)--University of Pretoria, 2013.
Odontology
unrestricted
32
Brittain, Roger. "Comparison of time taken and breakage of six different endodontic systems to prepare molar teeth." Thesis, University of the Western Cape, 2006. http://etd.uwc.ac.za/index.php?module=etd&.
Анотація:
The purpose of this study was to determine duration time, breakage and apical displacement, whilst using six different endodontic filing systems to prepare molar teeth. A total of 96 molar teeth were used in the study, divided equally, ie 16 teeth per system selected randomly, totalling 48 canals per system. A standardised access cavity was prepared for all the teeth before selection. The canals were filed according to the manufacturers&rsquoguidelines. The result showed that PROTAPER®
, K3&trade
and the combination of: HERO Shaper®
, HERO Apical®
and Endoflare®
(Referred from hereon as HERO System for convenience) were statistically faster than PROFILE®
and FlexMaster®
, which were in turn faster than AETTM. Although breakage did occur in K3&trade
and HERO System this was not deemed statistically significant. Apical displacement occurred in the form of Type 1 in the AETTM, PROFILE®
and HERO System, but once again this was not statistically significant. It was concluded that more aggressive cutting features such as a positive rake
angle, pyramidal shaped tip, progressive taper and absence of radial lands, if present, could have enabled K3&trade
, HERO System and PROTAPER®
to have faster times, and in addition these features did not compromise these systems with regard to apical foramina transportation and breakage.
33
Tan, Siow Wah. "Factors affecting the length of survival of permanent teeth after first-time non-surgical root canal treatment." Click to view the E-thesis via HKUTO, 2003. http://sunzi.lib.hku.hk/hkuto/record/B31954303.
34
Brice, Garth Loyola. "The interrelationship of epithelial rests of Malassez with orthodontic root resorption and repair in man /." Title page, contents and summary only, 1988. http://web4.library.adelaide.edu.au/theses/09DM/09dmb849.pdf.
35
Duggan, Derek Trope Martin. "In vivo microleakage evaluation of two root filling materials in teeth without a coronal seal." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2008. http://dc.lib.unc.edu/u?/etd,1777.
Анотація:
Thesis (M.S.)--University of North Carolina at Chapel Hill, 2008.Title from electronic title page (viewed Sep. 16, 2008). "... in partial fulfillment of the requirements for the degree of Master of Science in the School of Dentistry Endodontics." Discipline: Endodontics; Department/School: Dentistry.
36
Tan, Siow Wah, and 陳曉華. "Factors affecting the length of survival of permanent teeth after first-time non-surgical root canal treatment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B31954303.
37
Kristerson, Lars. "Autotransplantation of teeth influence of different factors on periodontal and pulpal healing ; a clinical and experimental study /." Stockholm : Dept. of Oral Surgery and Periodontology, Karolinska Institutet, 1985. http://catalog.hathitrust.org/api/volumes/oclc/12018151.html.
38
Foreman, P. C. "The micromorphology and composition of mineralised deposits within the root-canal systems of permanent human teeth." Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373054.
39
Zhang, Wen. "A randomized controlled clinical trial of oral health promotion strategies to prevent and arrest root caries among Hong Kong's eldering." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43278498.
40
Lee, Kwok-lun. "The oral epidemiology of 45-64 year-old Chinese residents of a housing estate in Hong Kong coronal and root caries /." Click to view the E-thesis via HKUTO, 1988. http://sunzi.lib.hku.hk/HKUTO/record/B38628260.
41
Navaei, Mahshid, and Omolbanin Nazari. "Endodontically Treated Teeth in General Dentistry- Identification of Factors Related to Treatment." Thesis, Umeå universitet, Institutionen för odontologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-143973.
Анотація:
ABSTRACT There are various factors that affect the success and outcome of root canal treatment. The aim of the study is to thoroughly investigate the prognosis of endodontic treated by general dental practitioners in the region of Västerbotten, Sweden, and try to identify factors that are related to an unsuccessful root canal treatment. Our hypothesis is about prognosis for teeth, which are treated by a general dentist, is worse than the teeth, which are treated by specialists, and dental students. Total 210 patients were included in our study. Of those 100 were excluded due to lack of documentation. We analysed these factors, aseptic treatment e.g. rubber dam, quality of root filling length, coronal restoration, and radiograph after 4 years. In our study, rubber dam was used only in 64 teeth (58 %) throughout whole treatment and only in 27 teeth (22 %) have seen that root filling follow the standard criteria. Twenty-two teeth (20 %) have received coronal restoration and only 21 teeth (19 %) had radiograph after 4 years, six teeth (5 %) had retreatment and 5 teeth (4 %) have been extracted. Lack of documentation was another striking finding which made it difficult for our study to extract complete information. In conclusion, we identified some factors, which can be improved. Inadequate documentation. Deficiencies in pre-treatment diagnostics. Aseptic treatment e.g. rubber dam Failure in follow-up documentation of treated teeth Quality of root filing.Enodontics
42
Granberg, Lisa, and Julia Stevens. "Diagnostic Accuracy of Radiological Methods Regarding Root Resorption of Teeth Neighbouring Impacted Maxillary Canines - A systematic review." Thesis, Malmö universitet, Odontologiska fakulteten (OD), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19748.
Анотація:
Syfte: Syftet med denna studie var att systematiskt granska den vetenskapliga litteraturengällande diagnostisk tillförlitlighet för röntgenmetoder avseende rotresorption på granntändertill överkäkshörntanden.Material och metod: För att uppnå en systematisk och ett transparant tillvägagångssättanvändes PRISMA och CRDs handbok. Sökningen gjordes i fyra olika databaser, PubMed,Cochrane, Web of Science och Scopus av de två författarna. De inkluderade studiernakvalitetsgranskades enligt QUADAS-2 dokument.Resultat: Sökningen resulterade i 2175 studier. Fem studier inkluderades i dennasystematiska litteraturöversikt och alla rapporterade diagnostisk tillförlitlighet. Intraoralperiapikal röntgen, panorama, CT och CBCT var olika indextest i studierna. Extraherade tänder, CT och CBCT användes som referensstandard. Låg risk för bias visades i ungefär hälften av domänerna gällande risk för bias och för alla domäner gällande applicerbarhet. Tillförlitligheten hos tredimensionell röntgen varierade mellan 0,85-1,0 och tillförlitligheten hos tvådimensionell röntgen varierade från 0,45 till 0,78.Konklusion: Denna systematiska litteraturöversikt visade att tredimensionell röntgen hadehögst sensitivitet och specificitet gällande rotresorption på granntänder till överkäkshörntänder. CBCT visade en högre tillförlitlighet än tvådimensionell röntgen. Även om CBCT har högre tillförlitlighet så har den också en högre strålningsdos och är inte alltid fördelaktig.Aim: The aim of this study was to systematically review the scientific literature in diagnosticaccuracy of radiographic methods regarding root resorption of teeth neighbouring impactedmaxillary canines.Material and method: In order to get a systematic and transparent approach, the PRISMAstatement and CRD’s guidance was followed. Four databases were searched, PubMed,Cochrane, Web of Science and Scopus by the two authors. The included studies were evaluated by the QUADAS-2 tool for quality assessment.Result: The search resulted in 2175 studies. Five studies were included in this review andall of them reported diagnostic accuracy. Intraoral periapical radiograph, panorama, CT andCBCT was used as index test among the studies. Extracted teeth, CT and CBCT was used asreference test. Low risk of bias was shown in approximately half of the domains for risk of biasand for all domains regarding applicability. The accuracy of three-dimensional ranged from0.85-1.0 and the accuracy of two-dimensional ranged from 0.45-0.78.Conclusions: According to this systematic review, three-dimensional imaging showed thehighest sensitivity and specificity regarding root resorptions caused by impacted maxillarycanine. CBCT showed higher accuracy than two-dimensional imaging. Though, CBCT hashigher accuracy it also has a higher radiation dose and might not always be beneficial regarding treatment planning. Therefore, CBCT should be used with respect and not routinely.
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Alhaddad, Khalifa W. "Impact on Bacterial Micro-leakage in Exposed Root Canal Obturation Material in Teeth Irrigated with Different Solutions." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/5762.
Анотація:
Purpose: Determine the timeframe of bacterial penetration that occurs to the apex when obturation material (gutta percha) is exposed to bacteria for a set period of time (45 days) and to determine if bacterial penetration of the obturated root is influenced by the type of irrigant used during the final rinse (17% EDTA vs 2% Chlorhexidine vs full strength 5.25% NaOCl). Methods: Thirty-six extracted teeth, including six controls, were instrumented and irrigated with 5.25% NaOCl followed by a final rinse of either: 17% EDTA, 2% Chlorhexidine, or 5.25% NaOCl, and then obturated. Each root was suspended between two chambers: the coronal chamber inoculated with brain heart infusion broth and 〖10〗^8 colony-forming units of Enterococcus faecalis, the apical chamber with brain heart infusion broth. The latter was checked daily for turbidity, indicating bacterial leakage. Results: After excluding teeth with clear indications of experimental failure, 21 teeth were included in the analysis. Leakage rates were not significantly difference across the three groups (Chlorhexidine: 14%, EDTA: 67%, NaOCl: 50%; p-value=0.1581). Time to leakage was not significantly difference across the three groups (p-value=0.2470). Conclusion: Within the limitations of this study it was shown that leakage occurs between 4-42 days and that there was no significant difference between the different solutions in preventing leakage.
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Brustolin, Juliane Priscila. "Pulpectomias em dentes decíduos realizadas por estudantes de Odontologia : estudo prospectivo." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/128192.
Анотація:
Este estudo prospectivo com base universitária buscou avaliar as taxas de sucesso clínico e radiográfico e fatores associados às falhas presentes em pulpectomias realizadas em dentes decíduos, por alunos de graduação de uma instituição de ensino. A amostra de conveniência foi composta por pacientes com idade entre 3 e 10 anos que buscaram atendimento na instituição e necessitavam de tratamento endodôntico. Os dados referentes ao tratamento como, por exemplo, tipo de dente envolvido (anterior ou posterior), condição clinica do dente, diagnóstico pulpar, utilização de EDTA após o preparo químico-mecânico, uso de medicação intra-canal, técnica utilizada para obturação do canal, qualidade da obturação realizada, tipo de material restaurador elegido (RC, CIVRM), número de avaliações e o tempo de consulta clínica foram coletados por um único avaliador em um prontuário específico para o procedimento endodôntico. Ainda, fatores potencialmente associados à falha do tratamento endodôntico também foram investigados incluindo sexo (feminino ou masculino), idade, Índice de Placa Visível (IPV) e Índice de Sangramento Gengival (ISG), número de dentes cariados, perdidos ou obturados (CPOD) e ainda o comportamento da criança durante o atendimento. Curva de sobrevida de Kaplan-Meier com teste de log-rank foi utilizada para analisar a longevidade das pulpectomias (p<0.005). Um total de 81 pulpectomias realizadas em 62 crianças com idade media de 5.6 anos (+-1.5) foram incluídas nas análises. A sobrevida das pulpectomias alcançou 62,9% aos 12 meses de acompanhamento, com taxa de falha anual (TFA) de 28,9% sendo que, a maioria das falhas ocorreu entre o primeiro e o terceiro mês de avaliação (p<0.001). Dentes restaurados com resina composta apresentaram maior longevidade do que aqueles tratados com cimento de ionômero de vidro resinoso (p=0.006). Não foi encontrada diferença estatística em outros parâmetros clínicos e individuais investigados. As pulpectomias realizadas em dentes decíduos por estudantes de graduação apresentaram baixa taxa de sucesso.This prospective university-based study aimed to evaluate the success rate and factors associated to failure of pulpectomies performed in primary teeth by undergraduate students. The convenience sample comprised patients aged 3 to 10 years who were under care in the institution and underwent primary tooth pulpectomies. Treatment-related data, such as type of tooth involved (anterior or posterior teeth), presence of dental pain, tooth status, pulp diagnosis, EDTA treatment after chemic-mechanical preparation, use of intra-canal medicament, technique used for endodontic filling, quality of endodontic obturation, type of restorative material used (CR; RMGIC), number of appointments and consult time were collected by a single evaluator on a specific chart for endodontic procedure. Also, Factors potentially associated with treatment failure were also investigated, including gender (male; female), patient age, Visible Plaque (VPi) and Gingival Bleeding (GBi) index, decayed, missed and filled teeth (dmft), and child behaviour. Kaplan–Meier survival curve with log-rank test was used to analyze the longevity of pulpectomies (p<0.005). Lastly, 81pulpectomies placed in 62 children (5.6 1.5 years) were included in the analysis. The survival of restorations reached 62.9% up to 12 months of follow-up, with overall annual failure rate (AFR) of 28.9%, and the majority of the failures occurred in the first 3 months (p<0.001). Teeth restored with composite resin presented more longevity than those teeth restored with RMGIC (p=0.006). The use of two or more sessions to perform the endodontic treatment resulted in more failures (p=0.028). Patients presenting gingivitis (GBI>20%) experienced more failures in their pulpectomies (p=0.006). There were no significant differences for the others individual and clinical parameters tested. The pulpectomies of primary teeth performed by undergraduate students presented low success rates.
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Mohamed, Razan Azahry Abdelhalim. "Antibacterial activity of different Iodoform-based preparations used as root filling materials in Paediatric Dentistry." University of the Western Cape, 2019. http://hdl.handle.net/11394/7533.
Анотація:
Magister Scientiae Dentium - MSc(Dent)Background: The primary goal of pulp therapy in the deciduous dentition is to keep the teeth fully functional in order to prevent arch space loss. A pulpectomy is a pulp therapy procedure indicated when an irreversibly inflamed or necrotic radicular pulp is encountered. ZOE and iodoform pastes (i.e. Kri 1 paste and Vitapex) have been recommended as root filling materials after pulpectomy. High clinical success rates have been reported with Vitapex and the fact that it resorbs readily when extruded beyond the apex is an added advantage. However, it has also been reported to resorb from within the root canals and even cause pathological root resorption in cases where the vital pulp is inflamed (Nurko et al., 2000). Iodoform-based preparations are thought to be more appropriate because they fulfill nearly all the requirements of the ideal root filling materials in primary teeth. Despite this, there are limited studies comparing the antibacterial effect of iodoform-based preparations. Aim: The aim of this study was to evaluate the antibacterial efficacy of Vitapex (V), Kri 1 paste (K) and pure iodoform (I) against E. faecalis.
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karashi, husain. "The Prevalence, Predictive Factors, and Classification of Intrapulpal Cracks in Maxillary Molars Requiring Endodontic Treatment." VCU Scholars Compass, 2017. http://scholarscompass.vcu.edu/etd/4755.
Анотація:
Diagnosis and treatment of teeth with longitudinal fractures is challenging. Cracks are usually not visible radiographically; they require a thorough evaluation to aid in diagnosis. Patients may be asymptomatic, demanding the dentist rely on clinical findings to make a diagnosis. Early diagnosis of the presence and extent of a crack is essential for the successful management of a cracked tooth. There is limited information in the literature regarding the prevalence or predictive factors of cracks extending into the pulp chamber of teeth. The purpose of this study was to determine the prevalence of intrapulpal cracks in maxillary molars and to identify factors that may aid in diagnosing the existence of a crack. All maxillary molar teeth requiring non- surgical root canal therapy or retreatment at the Virginia Commonwealth University graduate endodontic clinic from June 2016 through December 2016 were included in the study after obtaining patient consent. Teeth were examined visually, transilluminated, stained, and examined microscopically for the presence of an intrapulpal crack. Demographic information, subjective data associated with the chief complaint, objective results of diagnostic testing (percussion, palpation, bite stick test, transillumination, probing depths, existing restorations, and diagnosis) were analyzed using chi-square and logistic regression (p<0.05) to identify associations of these findings with the existence of a crack. A total of 18% (15/82 teeth) of maxillary molars that were evaluated and had endodontic treatment initiated were cracked. There was a significant association between cracked teeth and pain on biting (P<.0001) and with probing depths greater than 4 millimeters (mm) (P < 0.003). Those positive on a tooth slooth test were more likely to have an intrapulpal crack (P<.001) and teeth with a positive transillumination test were also found to be associated with the presence of a crack(P < .001).
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Gulabivala, Kishor. "Species richness of gram-positive coccoid morphotypes isolated from untreated and treated root canals of teeth associated with periapical disease." Thesis, University College London (University of London), 2004. http://discovery.ucl.ac.uk/1446602/.
Анотація:
Aims To estimate the species richness of gram-positive coccoid morphotypes (GPCM) from untreated and treated root canals of teeth with periapical disease, using partial 16S rRNA gene sequences and biochemical properties for identification. To further characterise the isolates by antibiotic sensitivity profiles and a subset of isolates by 16S-23S intergenic amplicon patterns. Methodology 195 isolates from 20 teeth (GPCM: 117 - untreated teeth; 78 - treated teeth) were investigated. 16S rDNA obtained from all isolates using universal primers was partially sequenced and the sequences aligned with those in databases using RDP and BLAST searches. The process of identity determination was analysed. Biochemical, commercial enzyme, and MIC tests by agar dilution and E-test (8 antibiotics) were also performed. Streptococcus, Staphylococcus, Enterococcus and Lactobacillus strains were evaluated by 16S-23S intergenic amplicon profile. The relatedness of like-strains was compared by: phylogenetic tree reconstruction using sequence data; and dendrograms using biochemical data. The putative identities from different approaches were compared. Results DNA concentration, PCR and sequencing primers, PCR protocol and origin of isolates ("untreated" or "treated") influenced sequence acquisition. The 16S rRNA sequence search method (RDP/BLAST), together with treated/untreated tooth origin, influenced putative strain identity. Thirty-eight percent of "untreated" isolates and half the "treated" isolates were identified with ? 98% sequence homology; the majority of the rest varied between 93%-97%. The 16S-23S intergenic amplicon patterns helped confirm genus designation and strain variation. Biochemical profiles were graded "unacceptable" in 38% of all isolates; a higher proportion was from treated teeth (46%:32%). Biochemical identities matched with 16S rRNA identities to genus level in 72% of isolates, to species level in 45%, and the rest did not match. MICs from agar dilution and E-test were within 2 dilutions in 90% of tests. Frequency distributions of MICs showed NCCLS (2003) breakpoint values to give reliable interpretive categories. Thirty-eight percent of isolates showed resistance, which was more common amongst "treated" isolates (53%:26%). Antibiotic resistance helped confirm or query identities and inform strain variation. Conclusions The 16S rRNA gene sequence, 16S-23S intergenic amplicon patterns and biochemical and MIC profiles gave different perspectives on isolates. Each approach provided accumulative evidence of subspecies strain variation and that strains colonising treated teeth may be influenced by treatment history.
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Le, Cabec Adeline. "Anterior dental loading and root morphology in Neanderthals." Toulouse 3, 2013. http://thesesups.ups-tlse.fr/1936/.
Анотація:
Distinguer les incisives et canines des Néanderthaliens de celles des hommes modernes peut représenter un défi dans le cas de dents isolées trouvées dans des collections de musée, ou provenant de contextes stratigraphiques perturbés. De plus, la morphologie de la couronne ne peut être utilisée dans le cas de dents fortement usées. Une étude préliminaire basée sur des échantillons limités et des mesures linéaires (Bailey, 2005) propose que la longueur des racines dentaires à elle seule permet de discriminer taxonomiquement les Néanderthaliens des hommes modernes du Paléolithique supérieur et actuels. Cette thèse teste cette hypothèse pour un échantillon de Néanderthaliens et d'hommes modernes, plus large géographiquement et chronologiquement, en utilisant la micro-tomographie. En plus de l'intérêt taxonomique d'explorer la taille et la forme des racines, nous discutons les implications fonctionnelles de la morphologie racinaire des dents antérieures dans le contexte de l'hypothèse des " dents-utilisées-comme-des-outils ", et des activités para-masticatrices. La première partie a été publiée comme suit : Le Cabec, A. , Kupczik, K. , Gunz, P. , Braga, J. , and Hublin, J. J. (2012). Long Anterior Mandibular Tooth Roots in Neanderthals Are Not the Result of their Large Jaws. Journal of Human Evolution, pp. 63, 667-681. DOI: 10. 1016/j. Jhevol. 2012. 07. 003. Cette partie valide la longueur des racines dentaires en tant qu'outil taxonomique pour distinguer les Néanderthaliens tardifs des hommes modernes du Paléolithique Supérieur et récents. En dépit de l'absence de corrélation entre la taille des racines et la taille de la symphyse mentonnière, les Néanderthaliens ont de grandes racines, pour la taille de leurs mâchoires. Il est alors proposé que les courtes racines des hommes modernes récents résulteraient d'une allométrie négative. La seconde partie a été publiée comme suit : Le Cabec, A. , Gunz, P. , Kupczik, K. , Braga, J. And Hublin, J. J. (2013). Anterior Tooth Root Morphology and Size in Neanderthals: Taxonomic and Functional Implications. Journal of Human Evolution, 64, pp. 169-193. DOI: 10. 1016/j. Jhevol. 2012. 08. 011. La morphologie racinaire est étudiée à travers un large échantillon d'hominidés fossiles et actuels, couvrant une large période chronologique et une vaste zone géographique. Les plus grandes longueurs racinaires observées chez les Néanderthaliens peuvent avoir résulté de la rétention d'une condition ancestrale. L'attribution taxonomique débattue de certains spécimens est discutée à la lumière de la morphologie racinaire des dents antérieures et montre que la longueur racinaire seule ne devrait pas être considérée comme suffisante pour une diagnose taxonomique. La fréquente présence d'hypercémentose et sa distribution non-homogène autour de l'apex racinaire pour les dents antérieures des Néanderthaliens pourrait refléter le régime de charge exercé sur les dents antérieures, probablement utilisées comme une troisième mainDistinguishing Neanderthal and modern human incisors and canines can be challenging in the case of isolated teeth found in museum collections, or from unclear stratigraphic contexts. In addition, the crown morphology cannot be used in the case of heavily worn teeth. A preliminary study based on limited samples and linear measurements (Bailey, 2005) proposed that root length alone can taxonomically discriminate Neanderthals from Upper Paleolithic and extant modern humans. This thesis investigates whether this remains true for a broader chronological and geographical sample of Neanderthals and modern humans, using micro-computed tomography. In addition to the taxonomic interest of investigating root size and shape, we discuss the functional implications of the anterior root morphology in the context of the 'teeth-as-tools' hypothesis and of para-masticatory activities. The first part was published as: Le Cabec, A. , Kupczik, K. , Gunz, P. , Braga, J. , and Hublin, J. J. (2012). Long Anterior Mandibular Tooth Roots in Neanderthals Are Not the Result of their Large Jaws. Journal of Human Evolution, 63, pp. 667-681. DOI: 10. 1016/j. Jhevol. 2012. 07. 003. This part validates root length as a taxonomical tool to distinguish late Neanderthals from Upper Paleolithic and recent modern humans. Despite the absence of correlation between root size and symphyseal size, Neanderthals have large roots for the size of their jaws. It is hypothesized that the short roots of extant modern humans result from a negative allometry. The second part was published as: Le Cabec, A. , Gunz, P. , Kupczik, K. , Braga, J. And Hublin, J. J. (2013). Anterior Tooth Root Morphology and Size in Neanderthals: Taxonomic and Functional Implications. Journal of Human Evolution, 64, pp. 169-193. DOI: 10. 1016/j. Jhevol. 2012. 08. 011. Root morphology is explored across a chronologically and geographically large sample of fossil and extant hominids. Longer roots in Neanderthals may have resulted from the retention of an ancestral condition. The debated taxonomic attribution of some specimens is discussed in light of anterior tooth root morphology and shows that root length alone should not be sufficient for taxonomic diagnosis. The frequent presence of hypercementosis and its non-homogeneous distribution around the root apex in Neanderthal anterior teeth could reflect the loading regime exerted on the front teeth, likely used as a third hand
49
Chiu, Mei-ling Bonnie. "Preparation of curved root canals with different nickel-titanium rotary systems three-dimensional comparison using micro-computed tomography /." Click to view the E-thesis via HKUTO, 2003. http://sunzi.lib.hku.hk/hkuto/record/B31954273.
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Chiu, Mei-ling Bonnie, and 趙美玲. "Preparation of curved root canals with different nickel-titanium rotary systems: three-dimensional comparisonusing micro-computed tomography." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B31954273.