Auswahl der wissenschaftlichen Literatur zum Thema „Auto-Obturation“

The aim of this study was to assess the micro leakage in three root canal obturation techniques viz. Warm vertical condensation, Cold lateral condensation and Thermafil using fluid filtration system. In this study the fluid filtration method is fabricated and used to assess the micro leakage in gutta-percha material obturated using three obturation techniques viz. Warm vertical condensation, Cold lateral condensation and Thermafil. The assessment system which can quantify the micro leakage present into the obturated root canal cavity is today's vital need to improve the further progress in endodontics and conservative dentistry. 45 No's of samples were taken for study and categorized into three, Category I: 15 No's of samples obturated using warm vertical condensation, Category II: 15 No's of samples obturated using cold lateral condensation and Category III: 15 No's of samples obturated using Thermafil. All obturated samples were tested using the fluid filtration system. The DSLR 1200D Canon and Auto CAD by Auto Desk were used to record the bubble displacement in the micropipette. The micro leakage reading are shown in Table 2 and tabulated values showed that Category II: 15 No's of samples obturated using cold lateral condensation, showed highest micro leakage value highest micro leakage followed by Category III: 15 No's of samples obturated using Thermafil and Category I: 15 No's of samples obturated using warm vertical condensation. Category III shown moderate leakage value. The study indicated that micro leakage evaluation using the fabricated fluid filtration system is most reliable quantitative method. On the basis of comparison of micro leakage assessment of three obturation techniques it is found that warm vertical condensed sample having least leakage over the Thermafil and Cold lateral condensation. The reason for micro leakage is shrinkage of gutta-percha during solidification to cause gap in between obturation material and canal wall which can be avoided by providing shrinkage allowance.

This study sought to evaluate the efficacy of SWEEPS in the removal of epoxy-resin-based and calcium-silicate-containing endodontic sealer combined with single-cone and carrier-based obturation techniques through a micro-CT analysis. Seventy-six single-rooted extracted human teeth with single root canal were instrumented with Reciproc instruments. Specimens were randomly divided into four groups (n = 19) according to the root canal filling material and obturation technique: (1) AH Plus sealer + Reciproc gutta-percha, (2) TotalFill BC sealer + TotalFill BC Points, (3) AH Plus sealer + Guttafusion obturator, and (4) MTA Fillapex + Guttafusion obturator. All specimens were re-treated one week later using Reciproc instruments. Following re-treatment, root canals were additionally irrigated using the Auto SWEEPS modality. The differences in the root canal filling remnants were analyzed by micro-CT scanning of each tooth after root canal obturation, after re-treatment, and after additional SWEEPS treatment. Statistical analysis was performed using an analysis of variance (p < 0.05). The additional treatment with SWEEPS significantly reduced the volume of the root canal filling materials in all experimental groups compared to the removal of root canal filling using only reciprocating instruments (p < 0.05). However, the root canal filling was not removed completely from any of the samples. SWEEPS can be used to enhance the removal of both epoxy-resin-based and calcium-silicate-containing sealers, in combination with single-cone and carrier-based obturation techniques.

Introduction. Good physicochemical properties of endodontic materials are one of the main preconditions for successful endodontic treatment. Modern endodontic materials are expected to have good adhesiveness, stability and low solubility in order to enable high-quality and permanent obturation of the root canal. The aim of this study was to test in vitro the stability and degree of solubility of two endodontic materials: Mineral Trioxide Aggregate (MTA) and Gutta Flow. Materials and methods. The solubility of endodontic materials Mineral Trioxide Aggregate - MTA (Angelus) and Gutta Flow (Colthane) was tested by the aging method using artificial saliva according to the prescription of Ira and Shannon. Twelve samples of single-rooted teeth (6 MTA, 6 Gutta Flow) were used. The samples were analyzed after 7, 14, 21, 28 and 35 days. After obturation, the samples were longitudinally cut and filled with auto-polymerizing acrylate and stored in artificial saliva at a temperature of 37? ?} 2? C. Results. The results of the analysis of the longitudinal sections of the roots through MTA and Gutta Flow showed the absence of damage to both endodontic materials after 14 days of exposure to the artificial saliva. The appearance of the first morphological damage, as well as the weakening of the bonding with dentin wall, were observed on the 21st day with Gutta Flow, and on the 28th day with MTA from the beginning of the experiment. After a period of 35 days, both materials showed increased porosity, solubility and breaking of the bond with dentin wall of the root canal. Conclusion. Based on the obtained results, it can be concluded that MTA showed lower solubility and better adhesiveness with dentin wall of the tooth root canal than Gutta Flow.

Muitas são as técnicas propostas à obturação dos Sistemas de Canais Radiculares (SCR), todavia, nenhuma delas alcançam o completo selamento. Em 2013, foi introduzido o cone auto-ajustável CPoint, que promete adaptar-se às paredes de canais produzindo obturações tridimensionais. Portanto, objetivou-se realizar uma revisão de literatura a fim de discutir este material e elucidar sua eficácia na obturação dos SCR. Foi utilizada a base de dados PubMed, usando os descritores Endodontics, Obturation e\ou CPoint, nos últimos 10 anos. Encontrou-se 5 estudos, os quais foram incluídos na revisão. Dentre as avaliações, analisou-se sua biocompatibilidade, expansão lateral e a influência de penetração de cimento nos túbulos dentinários, independente dos pontos avaliados, os resultados apresentam-se promissores. Verificou-se que o cone deve ser associado, idealmente, a um cimento biocerâmico, possuindo duas porções principais: um núcleo central que confere características de inserção e um revestimento polimérico hidrofílico que expande radialmente até encontrar às paredes dos canais. Tanto a expansão do CPoint quanto a presa do cimento dão-se pela absorção da umidade presente no SCR. Em outros testes, proporcionou uma maior resistência à fratura das raízes obturadas, contudo, demonstrou defeitos significativos nas obturações quando associado ao cimento biocerâmico. Conclui-se que o CPoint representa uma opção às técnicas de obturação dos SCR, porém, é necessária a realização de mais estudos no intuito de confirmar seu desempenho e indicá-lo para uso clínico.Palavras-chave: Endodontia. Materiais Dentários. Obturação do Canal Radicular.

An in vitro investigation was conducted to assess the efficacy of Hedstrom and Rotary Retreatment File using Cone Beam Computed Tomography (CBCT) in removing obturating material from moderately to severely curved root canals. Thirty-six removed human molar teeth were split into two groups based on the canal curvature using the Schafer and Schneider method. Each group consisted of 18 teeth. Teeth in Group A had roots that were moderately curved (angles between 10 and 20 degrees), whereas teeth in Group B had roots that were severely curved (angles more than 20 degrees). Following decoronation, each root was ready for obturation using the appropriate rotary files, following the manufacturer’s recommendations. Using the CBCT image, the total surface area of the root canals in the axial cross-section and the volume analysis of the obturated area were calculated. H files were used to retreat half of each group, while Rotary (ProTaper) retreatment files were used for the other half, in accordance with their retreatment protocol. It was noted how long it took to reach the working length and remove all obturating items. Cone beam computed tomography and Auto CAD software are used to analyze the surface area and volume of any residual obturating material in the canal after it has been completely removed. An analysis of the data using the ANOVA test was conducted between four groups. When p < 0.05 was reached, it was deemed statistically significant. Rotary retreatment files were discovered to be the most efficient method for removing obturating material and to take the least amount of time to achieve working length. Compared to the Rotary retreatment file, the H file left greater residue in the root canal. Compared to moderately curved root canal groups, severely curved root canal groups have noticeably more residues. In all four groups, the apical part had more residues than the middle and coronal portions. The obturating substance in the root canal could not be entirely removed using any of the retreatment procedures. Furthermore, there was no advantage in terms of root-filling removal’s effectiveness.

L’auto-obturation est une fonctionnalité de certains réservoirs de carburant d'aéronefs, leur permettant de colmater automatiquement des fuites. La technologie a peu évolué depuis la seconde guerre mondiale et est basée sur le gonflement d’une mousse de caoutchouc naturel, intercalée entre deux parois souples, au contact du carburant. Le fonctionnement de la technologie actuelle est d'abord analysé. La progression du carburant suit une loi ressemblant à de la diffusion mais avec une constante apparente de trois ordres de grandeur plus élevée que dans la résine seule. Le carburant provoque un gonflement mais aussi une transition entre un état compressible à un état incompressible, reflété par l'augmentation du coefficient de Poisson. Grâce à cela, le gonflement en épaisseur (z) d'une paroi de mousse peut être redirigé, à volume constant, dans le plan (xy) et ainsi combler un dommage. Ceci a comme limites (i) la dépendance envers le confinement entre deux parois et (ii) la cinétique de gonflement dépendante du type de carburant. L’objectif de la thèse est le développement d’une technologie auto-obturante impliquant un mouvement programmé vers le comblement d'un dommage et déclenchable par tout type de carburant aéronautique. La méthodologie suivie est l’adjonction de mémoire de forme au caoutchouc naturel via l'incorporation d'un second réseau temporaire. L'emploi d'un semi-cristallin (HDPE, TPI) permet de programmer la fixation et la récupération d’une forme temporaire mais seulement par stimulus thermique. Pour répondre au stimulus chimique, un polymère amorphe ayant une bonne affinité avec le carburant et la Tg adéquate est identifié : le PS. Un travail de formulation est réalisé pour trouver les bonnes quantités de ce polymère et d'additifs. Le déclenchement au carburant est alors possible mais lent et se fait dans une seule direction de l’espace. Les résultats de la première partie sont exploités pour mettre en œuvre une solution plus rapide impliquant le moussage de notre résine à mémoire de forme. En agençant judicieusement des fragments de mousse programmés pour se dilater dans une direction donnée, l’obturation d'un dommage de plusieurs centimètres est obtenue en moins de 10 minutes au contact de différents carburants. Le recyclage et la réutilisation de mousses usagées par broyage et réincorporation à de la matière vierge sont évalués
Self-sealing is a property of certain aircraft fuel tanks allowing them to automatically seal leaks. Current technology has evolved little since the Second World War and is based on the swelling of a natural rubber foam sandwiched between two flexible walls in contact with fuel. At first the mode of operation of the current technology is analyzed. The progression of fuel follows a law resembling diffusion but with an apparent constant three orders of magnitude higher than in the neat resin, causing swelling but also a transition from a compressible to an incompressible state, reflected by an increase in the Poisson's ratio. Wherefrom, swelling in thickness (z) is redirected, at constant volume, in the (xy) plane to potentially seal a damage. This has two limitations: (i) dependence on the confinement between the two walls and (ii) the fuel type dependent swelling kinetics. The objective of the thesis is the development of a self-sealing technology involving a programmed movement of matter in the direction of damage triggered by any type of aviation fuel. The methodology followed involves induction of a shape memory property to natural rubber through incorporating a second, temporary network. Semicrystalline polymers (HDPE) and (TPI) enable the fixing and the recovery of a temporary shape but only with a thermal stimulus. To enable chemical triggering, an amorphous polymer with suitable Tg and good affinity with fuel is identified: PS. A formulation work is performed to find out the right amounts of this polymer and additives. Fuel triggering is possible but is slow and only in one direction of space. Triggering by fuel is then possible but slow and is done in a single direction in space. The results of the first part are exploited to implement a faster solution involving the foaming of our shape memory material. By arranging fragments of foam programmed to expand in a given direction, the obturation of a few centimeters wide damage is obtained in less than 10 minutes in contact with different fuels. Recycling and reuse of used foams by crushing and reincorporation into virgin material are assessed

Background: Obtura-II injectable thermoplasticised gutta-percha technique has been available for several years. However, thus far, there are no published studies that have evaluated its clinical and radiographic success in non-vital young traumatised permanent incisors in children where teeth are expected to survive for the life-span of the patient. Aim: Evaluating the clinical and radiographic success of Obtura-II system in the root canals of non-vital young traumatised permanent incisors in children; studying the effect of different demographic and prognostic factors on the success rate of the technique; and investigating the outcome for this technique when used to obturate auto-transplanted teeth in children and adolescents. Method: This study was a retrospective study evaluating the Obtura-II treatment outcomes. Clinical dental records and periapical radiographs of 667 patients who attended the trauma clinic at the Paediatric Dentistry Department at Leeds Dental Institute during the period 2003–2011 were screened. The obturated teeth were classified as either successful or failure according to criteria developed for this study. Various prognostic factors that could influence the clinical and radiographic outcome of the technique were recorded using a special data extraction proforma. The data were entered into SPSS, with simple descriptive analysis and bivariate analyses conducted subsequently. Furthermore, a logistic regression analysis was carried out with the aim of obtaining the relation between different prognostic factors and the treatment outcomes. iv Results: According to the study criteria, 235 cases with 275 non-vital young permanent incisors with various stages of root development were included, in addition to 49 auto-transplanted teeth. The mean age of patients at the time of trauma was 10.2 years. The cases considered clinically successful accounted for 92.7% whilst the cases considered radiographically successful were 85.4% over a mean follow-up period of 51 months for the traumatised teeth. In addition, the clinical and the radiographic success for the auto-transplanted teeth were 97.9% and 93.8%, respectively. The logistic regression analysis showed a significant association between some of the prognostic factors, such as the type of trauma, the duration of Ca(OH)2 dressing, and the quality of obturation and the Obtura-II technique treatment outcomes in treating traumatised teeth. However, none of the factors associated significantly with the treatment outcomes in the cases of the auto-transplanted teeth. Conclusion: Obtura-II technique in the root canal treatment of the traumatised teeth was considered clinically successful in 92.7% and radiographically in 85.4% of the cases over a long follow-up period. In addition, when treating auto-transplanted teeth, the technique was clinically successful in 97.9% and radiographically in 93.8% of cases.