Desempenho biomecânico de novos retentores intrarradiculares em dentes com ou sem férula

• Autor(a) principal: Almeida, Letícia Nunes de
• Data de Publicação: 2020
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/12470
• topic: Retentores intrarradiculares; Compósito reforçado por fibra; Pino de fibra de vidro; Férula; Intraradicular retainers; Fiber-reinforced composite; Glass fiber post; Ferrule; CIENCIAS DA SAUDE::ODONTOLOGIA::CLINICA ODONTOLOGICA

The aim of this study was to evaluate the influence of intrarradicular post system and the amount of coronary remnant (ferrule) on maximal fracture load, fracture pattern and stress distribution of endodontically treated teeth. Eight experimental groups were created: Pf-0 e Pf-2 - glass fiber post (GFP) no. 3 in teeth with and without ferrule respectively; GFP no. 1 relined with experimental composite (EC) with and without ferrule respectively; EC-0 and EC-2 - custom post made with the experimental composite (EC) with and without ferrule respectively, CAD-0 e CAD-2 - custom milled post with and without ferrule respectively. The EC was composed of 22.5 wt% of methacrylate resin (Bis-GMA, TEGDMA, Bis-EMA), 30% of glass fibers and 47.5% of filler particles. After endodontic treatment, post cementation and crowns with composite resin, the teeth were tested to verify the maximum fracture load (n = 10) in a universal testing machine (Instron 5965) a 0.5 mm/min. Subsequently, the fracture pattern was analyzed and stress distribution was evaluated by the finite element method using the modified von Mises criterion (MSC Marc & Mentat). The maximum fracture load results were subjected to factor analysis, and subsequently Kolmogorov-Smirnov, ANOVA, Tukey and T-Test for comparison between groups (α = 0.05). Interaction was observed between the factors under study (p = 0.046), and ANOVA and Tukey showed a statistically significant difference between the groups (p = 0.001). EC-0 (752.81N) and CAD-0 (728.84N) were similar and superior Pr-0 (545.16) and Pf-0 (498.01N). In ferrule groups, all retainers were similar (p>0.05) Pf-2 (791.85), Pr-2 (699.1), EC-2 (822,81), CAD-2 (779.89). Pf-0 showed a greater number of non-repairable failures and the Pr-2 posts promoted a greater number of favorable failures. Groups without ferrule showed higher number of non-repairable failures. The posts made with EC showed lower stress concentration and the posts made by CAD / CAM technique, the highest stress concentration. Retainer type and presence of ferrule influence on maximal load, fracture pattern and stress distribution of endodontically treated teeth. CE custom posts promote higher maximum fracture load and more favorable stress distribution.