Prevalence of sleep bruxism in children: A systematic review

INTRODUCTION: Prevalence of sleep bruxism (SB) in children is subject to discussions in the literature. OBJECTIVE: This study is a systematic literature review aiming to critically assess the prevalence of SB in children. METHODS: Survey using the following research databases: MEDLINE, Cochrane, EMBASE, PubMed, Lilacs and BBO, from January 2000 to February 2013, focusing on studies specifically assessing the prevalence of SB in children. RESULTS: After applying the inclusion criteria, four studies were retrieved. Among the selected articles, the prevalence rates of SB ranged from 5.9% to 49.6%, and these variations showed possible associations with the diagnostic criteria used for SB. CONCLUSION: There is a small number of studies with the primary objective of assessing SB in children. Additionally, there was a wide variation in the prevalence of SB in children. Thus, further, evidence-based studies with standardized and validated diagnostic criteria are necessary to assess the prevalence of SB in children more accurately.INTRODUÇÃO: a prevalência de bruxismo do sono (BS) na população infantil é tema de discussões na literatura. OBJETIVO: assim, este trabalho, por meio de uma revisão sistemática, teve como objetivo avaliar, de forma crítica, a prevalência de BS em crianças. MÉTODOS: foi feito um levantamento nas bases de pesquisa MEDLINE, Cochrane, Embase, PubMed, Lilacs e BBO, entre os anos de 2000 e fevereiro de 2013, com enfoque em estudos que avaliaram especificamente a prevalência de BS em crianças. RESULTADOS: após a aplicação dos critérios de inclusão, chegou-se a quatro estudos. Entre os artigos selecionados, as taxas de prevalência de BS variaram de 5,9% a 49,6%, sendo que essas variações apresentaram possíveis associações com os critérios diagnósticos para BS. CONCLUSÃO: verifica-se um número reduzido de estudos que apresentaram o objetivo primário de avaliar o BS em crianças, além de uma grande variação nas taxas de prevalência. Torna-se necessária a realização de novos estudos, baseados em métodos de evidências e com critérios diagnósticos padronizados e validados, para avaliar com maior precisão a prevalência do BS em crianças.Federal University of Santa MariaFederal University of São PauloFederal University of ParanáUFSMUNIFESPSciEL

Resistência à fratura e padrão de falha de dentes submetidos ao clareamento interno com peróxido de carbamida a 37%, com aplicação de diferentes procedimentos restauradores

OBJECTIVE: This study investigated the compressive fracture strength and failure pattern in premolars submitted to endodontic treatment and internal bleaching with 37% carbamide peroxide for 21 days, with application of different restorative procedures. MATERIAL AND METHODS: Six groups were employed (n = 10): 1) non-bleached teeth and pulp chamber sealed with IRM; 2) bleached teeth and pulp chamber sealed with IRM; 3) bleached teeth and pulp chamber filled with light cured composite resin; 4) bleached teeth, root canals prepared at 10mm, filling of the root canal and pulp chamber with IRM; 5) bleached teeth, root canals prepared at 10mm, luting of prefabricated metallic post with zinc phosphate and pulp chamber sealed with composite resin; 6) bleached teeth, root canals prepared at 10mm, luting of glass fiber post with resin cement and pulp chamber sealed with composite resin. After 24-hour storage in distilled water, the specimens were submitted to compressive fracture strength testing in a universal testing machine. RESULTS: The following values were found: Group 1 - 56.23kgf; Group 2 - 48.96kgf; Group 3 - 53.99kgf; Group 4 - 45.72kgf; Group 5 - 54.22kgf; Group 6 - 60.12kgf. The analysis of variance did not reveal statistically significant difference between groups (pOBJETIVO: O objetivo do estudo foi investigar a resistência à fratura sob compressão e padrão de falha de pré-molares tratados endodonticamente e clareados internamente por 21 dias com peróxido de carbamida a 37%, aplicando-se diferentes procedimentos restauradores. MATERIAL E MÉTODOS: O objetivo deste estudo foi investigar a resistência à fratura sob compressão e padrão de falha de pré-molares unirradiculares tratados endodonticamente e clareados internamente com peróxido de carbamida a 37%. Foram constituídos 6 grupos (n = 10): 1) dentes sem clareamento e câmara pulpar vedada com IRM; 2) dentes clareados e câmara pulpar vedada com IRM; 3) dentes clareados e câmara pulpar preenchida com resina composta fotopolimerizável; 4) dentes clareados, condutos preparados com 10mm, e preenchimento do conduto e câmara pulpar com IRM; 5) dentes clareados, condutos preparados com 10mm, cimentação de pino metálico pré-fabricado com fosfato de zinco e câmara pulpar vedada com resina composta; 6) dentes clareados, condutos preparados com 10mm, cimentação de pino de fibra de vidro com cimento resinoso e câmara pulpar vedada com resina composta. Após 24 horas de armazenamento em água destilada, os espécimes foram submetidos ao teste de resistência à fratura sob compressão em máquina de ensaios universal. RESULTADOS: Os seguintes valores foram encontrados: grupo 1 - 56,23kgf; grupo 2 - 48,96kgf; grupo 3 - 53,99kgf; grupo 4 - 45,72kgf; grupo 5 - 54,22kgf; grupo 6 - 60,12kgf. A Análise de Variância não mostrou diferença estatisticamente significante entre os grupos (p < .05), sugerindo que o clareamento interno com peróxido de carbamida a 37% não enfraqueceu os tecidos dentais. O maior número de fraturas desfavoráveis foi encontrado nos grupos 2 (50%), 4 (40%), e 5 (30%). O grupo 6 exibiu o padrão de falhas mais favorável. CONCLUSÃO: Os resultados sugerem que o clareamento interno com peróxido de carbamida a 37% não causou enfraquecimento importante dos dentes. Entre os dentes clareados, aqueles com restaurações temporárias de IRM ou com pinos metálicos mostraram o padrão mais desfavorável de fratura, enquanto o padrão de fratura mais favorável ocorreu em dentes restaurados com resina composta e pinos de fibras de vidro

Utilization of biological posts to reconstruct weakened roots

Adequate reconstruction of endodontically treated teeth with severe loss of dentine tissue is one of the challenges of Restorative Dentistry. None of the commercially available pre-fabricated intraradicular posts meets all ideal biological and mechanical properties. Recently, a technique for the reconstruction of pulpless teeth with weakened roots has been indicated – the use of dental posts obtained from natural teeth. This article presents, through a clinical case, important details for the execution of the technique

In vitro wear resistance of three types of polymethyl methacrylate denture teeth

The wear resistance of denture teeth is important to the longevity of removable prostheses of edentulous patients. The ability of denture teeth to maintain a stable occlusal relationship over time may be influenced by this property. The purpose of this in vitro study was to evaluate the wear resistance of polymethyl methacrylate (PMMA) denture teeth based on their chemical composition when opposed by a ceramic antagonist. The maxillary canines (n=10) of 3 PMMA denture teeth (Trubyte Biotone, cross-linked PMMA; Trilux, highly cross-linked IPN (interpenetrating polymer network)-PMMA; and Vivodent, highly cross-linked PMMA) were secured in an in vitro 2-body wear-testing apparatus that produced sliding contact of the specimens (4.5 cycles/s, sliding distance of 20 mm, under 37°C running water) against glazed or airborne particle abraded ceramic. Wear resistance was measured as height loss (mm) under 300 g (sliding force) after 100,000 cycles, using a digital measuring microscope. Mean values were analyzed by 2-way ANOVA and Tukey's test (a=0.05). The wear of Trubyte Biotone (0.93 ± 0.14 mm) was significantly higher than that of both other types of teeth tested against abraded ceramic (p<0.05). The Vivodent tooth (0.64 ± 0.17 mm) exhibited the best wear resistance among the denture teeth tested against airborne particle abraded ceramic. There were no statistically significant differences (p>0.05) in wear among the 3 denture teeth evaluated against glazed ceramic. Trilux and Vivodent teeth tested against either glazed or airborne particle abraded ceramic did not differ significantly from each other (p<0.05). All teeth showed significantly more wear against airborne particle abraded ceramic than against glazed ceramic (p<0.05). In conclusion, the three types of PMMA denture teeth presented significantly different wear resistance against the abraded ceramic. The high-strength PMMA denture teeth were more wear-resistant than the conventional PMMA denture tooth.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Evaluation of fracture resistance of teeth with flared root canals reconstructed with prefabricated glass fiber posts (associated with accessory posts or fiber strips) or with anatomic posts

Avaliou-se a resistência à fratura de dentes tratados endodonticamente e reconstruídos com núcleos metálicos fundidos ou com diferentes procedimentos restauradores empregando pinos de fibras de vidro. Selecionaram-se 50 dentes caninos seccionados na junção cemento-esmalte, tratados endodonticamente e fixados em blocos de resina acrílica. Os dentes foram distribuídos aleatoriamente em cinco grupos, subdividididos de acordo com o tratamento instituído (10 espécimes cada): 1) núcleo metálico fundido com liga de Ni-Cr (grupo controle); 2) pino de fibras de vidro convencional FibreKor n° 2 (1,25mm de diâmetro); 3) pino de fibras de vidro envolvido por fitas de fibras de vidro (Interlig); 4) pino de fibras de vidro combinado com pinos acessórios de fibras de vidro (Reforpin); 5) pino anatômico (pino de fibras de vidro reembasado com resina composta de baixa viscosidade (Filtek Flow). O preparo do conduto nos cinco grupos simulou raízes com canais largos e foi executado de forma escalonada (dois degraus). Para este preparo, utilizou-se a ponta diamantada 1016HL (diâmetro de 1,8mm), que penetrou 10mm no conduto (profundidade total de preparo do conduto). A seguir, a ponta diamantada 3017HL (diâmetro de 2,5mm) penetrou 5mm no conduto. Realizou-se a cimentação dos pinos com sistema adesivo Scotchbond Multi-Uso Plus e cimento resinoso RelyX CRA. Coroas totais metálicas fundidas em liga de Níquel-Cromo foram cimentadas sobre a porção coronária de todos os espécimes. Os espécimes foram armazenados por 24 horas em água destilada a 37°C e submetidos ao teste de resistência à fratura sob compressão na máquina de ensaios universal Kratos. A carga foi aplicada em ângulo de 135° com o longo eixo da raiz, na velocidade de 0,5mm/min. Os valores de resistência à fratura encontrados foram, em ordem decrescente: Grupo 1 ? 110,85kgf; Grupo 4 - 93,88kgf; Grupo 5 ? 89,34kgf; Grupo 3 - 79,07kgf; Grupo 2 - 76,04kgf, sendo que a análise estatística (ANOVA e Tukey) demonstrou diferença estatisticamente significativa (p < 0,05) entre o grupo 1 e o grupo 2, bem como entre o grupo 1 e o grupo 3. Em relação ao padrão de fratura, observou-se: grupo 1 ? todas as raízes fraturaram (60% no terço médio); grupo 2 e grupo 4 - 40% de fraturas no terço cervical da raiz e 30 a 40% de falhas da porção coronária do núcleo; grupo 3 ? predominância de fraturas no terço cervical da raiz (60%); grupo 5 ? 50% das falhas na porção coronária do núcleo.This study evaluated the fracture resistance of endodontically treated teeth reconstructed with cast metallic posts or different restorative procedures using glass fiber posts. Fifty canines were sectioned at the cementoenamel junction, endodontically treated and fixated in acrylic resin blocks. Teeth were randomly divided into five groups (10 specimens each): 1) cast metallic post (control group); 2) conventional glass fiber post FibreKor n. 2 (1.25mm diameter); 3) glass fiber post surrounded by glass fiber strips (Interlig); 4) glass fiber post combined with accessory glass fiber posts (Reforpin); 5) anatomic post (glass fiber post covered with low-viscosity composite resin (Filtek Flow). Root canal preparation in the five groups simulated roots with wide root canals and was performed by the step-down technique (two steps). This preparation was performed with a diamond bur n. 1016HL (1.8-mm diameter), which penetrated into the root canal in 10mm (total depth of root canal preparation). The cervical step was prepared with 5-mm depth with a diamond bur n. 3017HL (2.5-mm diameter). Posts were luted with the adhesive system Scotchbond Multi-Uso Plus and resin cement RelyX CRA. After fabrication of the coronal portion of posts (standardized with aid of polypropylene templates) with composite resin Enforce-Core, a metallic full crown cast in nickel-chromium alloy was cemented on it. Specimens were stored in distilled water at 37ºC for 24 hours and submitted to compressive fracture resistance test in a universal testing machine Kratos. Load was applied at 135° to the root long axis, at a crosshead speed of 0.5mm/min. Fracture resistance values were the following, in decreasing order: Group 1 ? 110.85kgf; Group 4 ? 93.88kgf; Group 5 ? 89.34kgf; Group 3 ? 79.07kgf; Group 2 ? 76.04kgf; statistical analysis (ANOVA and Tukey) revealed statistically significant difference (p < 0.05) between groups 1 and 2 and between groups 1 and 3. Concerning the pattern of fracture, all roots in group 1 presented fracture (60% at the middle third); groups 2 and 4 presented 40% of fractures at the cervical root third and 30 to 40% of failure at the coronal portion of the post; group 3 demonstrated predominance of fracture at the cervical root third (60%); in group 5, 50% of failures occurred at the coronal portion of the pos

Evaluation of Fracture Resistance of Endodontically Treated Teeth Reconstructed with Dentinal Post and Cores and Polyethylene Woven Fiber Ribbon Post and Cores

Avaliou-se a resistência à fratura de dentes tratados endodonticamente reconstruídos com pinos de fibras de polietileno e com pinos dentários. Para tal, selecionaram-se 60 caninos superiores humanos seccionados na junção cementoesmalte, tratados endodonticamente (condutos desobturados até a profundidade de 8mm) e fixados em blocos de resina acrílica. Distribuíram-se os corpos de prova aleatoriamente em quatro grupos de 15 unidades: 1) preparo convencional dos condutos e confecção de pinos de fibras de polietileno; 2) preparo convencional dos condutos e pinos dentários; 3) condutos medianamente alargados e pinos dentários; 4) condutos amplamente alargados e pinos dentários. Nos grupos 1 e 2, dilataram-se os condutos até a broca Largo de número 4; nos grupos 3 e 4, os condutos sofreram desgastes seqüenciais padronizados, simulando raízes medianamente ou amplamente destruídas. No grupo 4, a espessura das paredes do conduto no terço cervical era de 0,5mm. Realizou-se a cimentação dos pinos com sistema adesivo Scotchbond Multi-Uso Plus e cimento resinoso Enforce. Construiu-se a porção coronária dos núcleos com resina composta autopolimerizável reforçada com titânio Ti-Core. Armazenaram-se os espécimes por 24 horas em água destilada, submetendo-os então aos testes de resistência à fratura sob compressão na máquina de ensaios universal Kratos, até falha do sistema. A força de compressão foi de 100 kgf e a velocidade de 0,5mm/min, sendo aplicada em ângulo de 135° em relação ao longo eixo da raiz. Os valores de resistência à fratura encontrados foram, em ordem decrescente: Grupo 3 - 58,67kgf; Grupo 2 - 3,30kgf; Grupo 4 - 47,91kgf; Grupo 1 - 45,46kgf, sendo que a análise estatística (ANOVA e Tukey) demonstrou diferença estatisticamente significante somente entre os grupos 1 e 3. Em relação ao padrão de fratura, observou-se: Grupo 1 ampla predominância de fratura da porção coronária do núcleo; Grupo 2 e Grupo 3 padrão variado de fraturas (tanto radiculares como do pino e/ou porção coronária); Grupo 4 todas as raízes fraturaram.Fracture resistance of endodontically treated teeth reconstructed with polyethylene woven fiber ribbon post and cores and dentinal post and cores has been evaluated. For that purpose, 60 human maxillary canines were selected, cut on the cementoenamel junction, endodontically treated (non- filled canal to a depth of 8mm)and fixed in acrylic resin blocks. The specimens were randomly distributed in 4 groups of 15 units each: 1) conventional canal preparation and making of polyethylene woven fiber ribbon post and cores; 2) conventional preparation of canals and dentinal post and cores; 3) fairly flared canals and dentinal post and cores; 4) greatly flared canals and dentinal post and cores. On groups 1 and 2, canals were enlarged as much as number 4 Largo bur; on groups 3 and 4, canals were subjected to standardized sequential cutting to permit a simulation of fairly or greatly flared roots. On group 4, the width of canal walls on the gingival third was 0.5mm. Post cementation was performed with the use of Scotchbond Multi-Purpose Plus bonding agent and Enforce resin cement. The core was built with self-curing composite reinforced with Ti-Core titanium. Specimens were stored in distilled water for 24 hours and subsequently subjected to compression fracture resistance tests on the Kratos universal testing machine until system failure. Load of 100kgf was applied at a speed of 0.5mm/min at an 135° angle in relation to the long axis of the root. Fracture resistance under compression presented the following values (in decreasing order): 1) group 3 58.67kgf; 2) group 2 53.30kgf; 3) group 4 47.91kgf; 4) group 1 45.46kgf. Results were subjected to statistical analysis (ANOVA and Tukey),which only showed significant statistical difference between groups 1 and 3. As to the patterns of failure, the figures observed were: group 1 - 86.6% on the post and/or core; group 2 - 46.6% on the gingival third of the root and an equal figure for post and/or core; group 3 - 40% on the gingival third of the root and 53.3% on the post and/or core; group 4 - 66% on the gingival third of the root and 33.3% on the middle third of the root

Fracture strength of endodontically treated teeth reconstructed with woven polyethylene fiber posts and biological posts

Objective: To investigate the fracture strength and mode of endodontically treated teeth with structurally weakened roots reconstructed with woven polyethylene fiber posts and biological posts. Methods: After removing the crowns, 60 endodontically treated maxillary canines were distributed into 4 groups: 1) conventional root canal preparation and reconstruction with polyethylene fiber posts; 2) conventional root canal preparation and reconstruction with biological posts; 3) moderately flared root canals and reconstruction with biological posts; 4) widely flared root canals and reconstruction with biological posts. The posts were cemented with resin cement Enforce (Dentsply Ind. e Com., Petrópolis, Rio de Janeiro, Brasil) and the core was constructed with Ti-Core (EssentialDental Systems, S. Hackensack, NJ, USA) resin composite. The specimens were tested under compression in a universal testing machine. Results: The following fracture strength values were obtained: Group 1 – 45.46kgf; Group 2 – 53.30kgf; Group 3 – 58.67kgf; Group 4 – 47.91kgf, with statistically significant differences between Groups 1 and 3 (p<0.05). The following fracture modes were observed: Group 1 – predominance of fracture of the coronal portion of the post; Groups 2 and 3 – various fracture patterns; Group 4 – all roots fractured. Conclusion: Both posts were shown to be promising (adequate fracture strength and favorable pattern of fracture). Biological posts appear to be capable of reinforcing the root to some extent; however, fracture occured in all roots with widely flared root canals

Tensile bond strength of glass fiber posts luted with different cements Resistência à tração de pinos de fibra de vidro cimentados com diferentes materiais

Proper selection of the luting agent is fundamental to avoid failure due to lack of retention in post-retained crowns. The objective of this study was to investigate the tensile bond strength and failure mode of glass fiber posts luted with different cements. Glass fiber posts were luted in 40 mandibular premolars, divided into 4 groups (n = 10): Group 1 - resin-modified glass ionomer RelyX Luting; Group 2 - resin-modified glass ionomer Fuji Plus; Group 3 - resin cement RelyX ARC; Group 4 - resin cement Enforce. Specimens were assessed by tensile strength testing and light microscopy analysis for observation of failure mode. The tensile bond strength values of each group were compared by ANOVA and Tukey test. The significance level was set at 5%. The failure modes were described as percentages. The following tensile strength values were obtained: Group 1 - 247.6 N; Group 2 - 256.7 N; Group 3 - 502.1 N; Group 4 - 477.3 N. There was no statistically significant difference between Groups 1 and 2 or between Groups 3 and 4, yet the resin cements presented significantly higher tensile bond strength values than those presented by the glass ionomer cements. Group 1 displayed 70% of cohesive failures, whereas Groups 2, 3 and 4 exhibited 70% to 80% of adhesive failures at the dentin-cement interface. We concluded that resin cements and glass ionomer cements are able to provide clinically sufficient retention of glass fiber posts, and that glass ionomer cements may be especially indicated when the application of adhesive techniques is difficult.<br>A seleção adequada do agente cimentante é essencial para evitar falhas por perda de retenção em coroas retidas por núcleos. O objetivo deste estudo foi investigar a resistência à tração e o tipo de falha de pinos de fibra de vidro cimentados com diferentes materiais. Cimentaram-se pinos de fibra de vidro em 40 pré-molares inferiores, divididos em 4 grupos (n = 10): Grupo 1 - ionômero de vidro modificado por resina RelyX Luting; Grupo 2 - ionômero de vidro modificado por resina Fuji Plus; Grupo 3 - cimento resinoso RelyX ARC; Grupo 4 - cimento resinoso Enforce. Avaliaram-se os espécimes por teste de resistência à tração e análise por microscopia óptica para observação do tipo de falha. Compararam-se os valores de resistência à tração de cada grupo por análise de variância e teste de Tukey, sendo que o nível de significância estabelecido foi de 5%. Descreveram-se os tipos de falha na forma de porcentagens. Os valores de resistência à tração obtidos foram: Grupo 1 - 247,6 N; Grupo 2 - 256,7 N; Grupo 3 - 502,1 N; Grupo 4 - 477,3 N. Não houve diferença estatisticamente significativa entre os Grupos 1 e 2 ou entre os Grupos 3 e 4, porém os cimentos resinosos apresentaram valores de resistência à tração significativamente maiores do que os apresentados pelos cimentos ionoméricos. O Grupo 1 exibiu 70% de falhas coesivas, enquanto os Grupos 2, 3 e 4 apresentaram 70% a 80% de falhas adesivas na interface dentina-cimento. Concluiu-se que os cimentos resinosos e ionoméricos são capazes de proporcionar retenção clinicamente suficiente de pinos de fibras de vidro, e que os cimentos ionoméricos podem ser indicados principalmente quando houver dificuldades de aplicar técnicas adesivas

Fracture resistance and failure pattern of teeth submitted to internal bleaching with 37% carbamide peroxide, with application of different restorative procedures Resistência à fratura e padrão de falha de dentes submetidos ao clareamento interno com peróxido de carbamida a 37%, com aplicação de diferentes procedimentos restauradores

OBJECTIVE: This study investigated the compressive fracture strength and failure pattern in premolars submitted to endodontic treatment and internal bleaching with 37% carbamide peroxide for 21 days, with application of different restorative procedures. MATERIAL AND METHODS: Six groups were employed (n = 10): 1) non-bleached teeth and pulp chamber sealed with IRM; 2) bleached teeth and pulp chamber sealed with IRM; 3) bleached teeth and pulp chamber filled with light cured composite resin; 4) bleached teeth, root canals prepared at 10mm, filling of the root canal and pulp chamber with IRM; 5) bleached teeth, root canals prepared at 10mm, luting of prefabricated metallic post with zinc phosphate and pulp chamber sealed with composite resin; 6) bleached teeth, root canals prepared at 10mm, luting of glass fiber post with resin cement and pulp chamber sealed with composite resin. After 24-hour storage in distilled water, the specimens were submitted to compressive fracture strength testing in a universal testing machine. RESULTS: The following values were found: Group 1 - 56.23kgf; Group 2 - 48.96kgf; Group 3 - 53.99kgf; Group 4 - 45.72kgf; Group 5 - 54.22kgf; Group 6 - 60.12kgf. The analysis of variance did not reveal statistically significant difference between groups (p<0.05), suggesting that internal bleaching with 37% carbamide peroxide did not weaken the dental tissues. The largest number of unfavorable fractures was observed for Groups 2 (50%), 4 (40%), and 5 (30%). Group 6 exhibited the most favorable failure pattern. CONCLUSIONS: The results suggest that internal bleaching with 37% carbamide peroxide did not significantly weaken the teeth. Among the bleached teeth, those with temporary IRM restorations or metallic posts demonstrated the most unfavorable fracture pattern, whereas the most favorable fracture pattern occurred in teeth restored with composite resin and glass fiber posts.<br>OBJETIVO: O objetivo do estudo foi investigar a resistência à fratura sob compressão e padrão de falha de pré-molares tratados endodonticamente e clareados internamente por 21 dias com peróxido de carbamida a 37%, aplicando-se diferentes procedimentos restauradores. MATERIAL E MÉTODOS: O objetivo deste estudo foi investigar a resistência à fratura sob compressão e padrão de falha de pré-molares unirradiculares tratados endodonticamente e clareados internamente com peróxido de carbamida a 37%. Foram constituídos 6 grupos (n = 10): 1) dentes sem clareamento e câmara pulpar vedada com IRM; 2) dentes clareados e câmara pulpar vedada com IRM; 3) dentes clareados e câmara pulpar preenchida com resina composta fotopolimerizável; 4) dentes clareados, condutos preparados com 10mm, e preenchimento do conduto e câmara pulpar com IRM; 5) dentes clareados, condutos preparados com 10mm, cimentação de pino metálico pré-fabricado com fosfato de zinco e câmara pulpar vedada com resina composta; 6) dentes clareados, condutos preparados com 10mm, cimentação de pino de fibra de vidro com cimento resinoso e câmara pulpar vedada com resina composta. Após 24 horas de armazenamento em água destilada, os espécimes foram submetidos ao teste de resistência à fratura sob compressão em máquina de ensaios universal. RESULTADOS: Os seguintes valores foram encontrados: grupo 1 - 56,23kgf; grupo 2 - 48,96kgf; grupo 3 - 53,99kgf; grupo 4 - 45,72kgf; grupo 5 - 54,22kgf; grupo 6 - 60,12kgf. A Análise de Variância não mostrou diferença estatisticamente significante entre os grupos (p < .05), sugerindo que o clareamento interno com peróxido de carbamida a 37% não enfraqueceu os tecidos dentais. O maior número de fraturas desfavoráveis foi encontrado nos grupos 2 (50%), 4 (40%), e 5 (30%). O grupo 6 exibiu o padrão de falhas mais favorável. CONCLUSÃO: Os resultados sugerem que o clareamento interno com peróxido de carbamida a 37% não causou enfraquecimento importante dos dentes. Entre os dentes clareados, aqueles com restaurações temporárias de IRM ou com pinos metálicos mostraram o padrão mais desfavorável de fratura, enquanto o padrão de fratura mais favorável ocorreu em dentes restaurados com resina composta e pinos de fibras de vidro

Clinical performance and failure modes of pulpless teeth restored with posts: a systematic review

Abstract The aim of this systematic review was to compare the clinical performance and failure modes of teeth restored with intra-radicular retainers. A search was performed on PubMed/Medline, Central and ClinicalTrials databases for randomized clinical trials comparing clinical behavior and failures of at least two types of retainers. From 341 detected papers, 16 were selected for full-text analysis, of which 9 met the eligibility criteria. A manual search added 2 more studies, totalizing 11 studies that were included in this review. Evaluated retainers were fiber (prefabricated and customized) and metal (prefabricated and cast) posts, and follow-up ranged from 6 months to 10 years. Most studies showed good clinical behavior for evaluated intra-radicular retainers. Reported survival rates varied from 71 to 100% for fiber posts and 50 to 97.1% for metal posts. Studies found no difference in the survival among different metal posts and most studies found no difference between fiber and metal posts. Two studies also showed that remaining dentine height, number of walls and ferrule increased the longevity of the restored teeth. Failures of fiber posts were mainly due to post loss of retention, while metal post failures were mostly related to root fracture, post fracture and crown and/or post loss of retention. In conclusion, metal and fiber posts present similar clinical behavior at short to medium term follow-up. Remaining dental structure and ferrule increase the survival of restored pulpless teeth. Studies with longer follow-up are needed