RESUMO
This study investigated the effect of radiation timing on the bond strength of resin cement to intraradicular dentine. Fifty human teeth were distributed into 5 groups (n = 10): Control (nonirradiated teeth), Before-RCT (teeth irradiated before root canal treatment), After-CH (teeth irradiated after canal preparation and placement of calcium hydroxide intracanal dressing), After-RCT (teeth irradiated after completion of root canal treatment) and After-FPL (teeth irradiated after luting of a glass fibre post). Each tooth received 70 Gy irradiation. The roots were sectioned for push-out strength testing. After-RCT and After-FPL groups had significantly lower push-out strength than the control at the middle third (p < 0.05). Control and After-CH groups had a higher percentage of cohesive dentine failure. Radiotherapy after root canal obturation and post luting adversely affected the adhesiveness of resin cement to intraradicular dentine. Teeth irradiated before root canal treatment and after placement of calcium hydroxide had the best performance.
Assuntos
Colagem Dentária , Técnica para Retentor Intrarradicular , Humanos , Cimentos de Resina/uso terapêutico , Cimentos de Resina/química , Hidróxido de Cálcio/uso terapêutico , Dentina , Cavidade Pulpar , Preparo de Canal Radicular , Teste de Materiais , Vidro/química , Análise do Estresse DentárioRESUMO
INTRODUCTION: This study aimed to assess sagittal and vertical skeletal and dentoalveolar changes through the use of 3-dimensional imaging in prepubertal Class II malocclusion patients treated with a cantilever Herbst appliance (HA). Condyle-glenoid fossa positional changes were also quantified. METHODS: This retrospective cohort study assessed 22 children (11.2 years ± 1.2) consecutively treated with a cantilever HA for 12 months and 11 untreated children (aged 9.3 ± 0.30 years) that served as controls. Cone-beam computed tomography was performed at baseline (T1) and at the end of the observation period (T2). Movements in the regions of interest were measured as linear displacements from cone-beam computed tomography images through algebraic calculations. A Student t test for independent samples was used for group equivalence testing at T1, and the treatment differences between T2 and T1 were evaluated by 2 analyses of covariance, one considering the expected growth unit as a covariate and the other with an annualized factor. RESULTS: The largest dental movement was a mesial movement of mandibular molars (3.70 mm), whereas the largest skeletal changes consisted of a larger relative length of the mandible (difference of 1.2 mm) in the HA group than in the control group. CONCLUSIONS: Within the study limitations (retrospective cohort, historical control group, and sample size), 3-dimensional imaging suggests that HA corrected Class II malocclusion in a predominantly prepubertal sample through more dental than skeletal changes. The changes were more significant in the sagittal than in the vertical direction. In addition, relative stability in the condyle-fossa relationship was noted.
Assuntos
Má Oclusão Classe II de Angle , Aparelhos Ortodônticos Funcionais , Cefalometria , Criança , Humanos , Má Oclusão Classe II de Angle/diagnóstico por imagem , Má Oclusão Classe II de Angle/terapia , Mandíbula , Estudos RetrospectivosRESUMO
OBJECTIVES: This systematic review (SR) aimed to investigate the influence of obturation extent on the final outcome of root canal treatment (RCT), by answering the question "among patients requiring RCT on fully formed permanent teeth, is there an association between obturation extent and the final treatment outcome?" MATERIALS AND METHODS: Five electronic databases and three gray literature searches were performed. Observational studies investigating the association between obturation extent and RCT outcome in fully formed permanent teeth with a minimum follow-up of 12 months were included. We evaluated the risk of bias (RoB) in with MAStARI for cohort studies. The overall quality of the evidence was assessed with the GRADE-tool. RESULTS: Twenty-two studies were included, 2 had high RoB, 7 moderate RoB, and 13 low RoB. Underextended obturation demonstrated increased odds of an unfavorable outcome in seven studies, in which the odds varied between 6.94 (95%CI 2.20-21.87) and 1.73 (95%CI 1.02-2.95). Overextended obturation also demonstrated this association in four studies, with odds varying from 1.90 (95%CI 1.23-2.94) to 23.00 (95%CI 5.58-94.75). Due to heterogeneity and the very low level of evidence found in the GRADE analysis, the results from this SR should be interpreted with caution. CONCLUSIONS: Obturation extent seems to influence RCT outcome; overextended and underextended obturations showed higher chance of association with less favorable outcomes than adequate obturation; however, this association was not categorically supported. CLINICAL RELEVANCE: This SR provides information about obturation extent influence on RCT outcome and guides clinicians to make evidence-based decisions during endodontic practice.