Resistência à fratura de dentes com preparos cavitários MOD restaurados com resina composta e fibra de vidro

• Ano de defesa: 2007
• Autor(a) principal: Rodrigues, Fausto Borges
• Orientador(a): Burnett Junior, Luiz Henrique
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Pontifícia Universidade Católica do Rio Grande do Sul; Porto Alegre
• Palavras-chave em Português: ODONTOLOGIA; RESTAURAÇÃO DENTÁRIA; MATERIAIS DENTÁRIOS; ENDODONTIA; CAVIDADES DENTÁRIAS - PREPARAÇÃO; FRATURAS DENTÁRIAS; RESINAS COMPOSTAS; FIBRAS DE VIDRO; RESISTÊNCIA DOS MATERIAIS (ODONTOLOGIA)
• Link de acesso: http://hdl.handle.net/10923/457

The aim of this study was to evaluate in vitro the effect of two types of glass fibers, unidirectional or woven, placed inside of MOD cavity preparations on fracture strength of endodontically treated molars, either restored with composite resin, or not. Ninety sound human third molars were extracted, embedded in acrylic resin blocks and randomly assigned to six groups (n=15). Group 1 G1 (sound teeth), control. Groups G2, G3, G4, G5 e G6 were subjected to the following procedures: G2 – MOD cavity preparation; G3 – MOD and endodontic treatment (ET); G4 –MOD + ET + composite resin restoration (CR); G5 – MOD + ET + unidirectional fiber (UF) + CR; G6 - MOD + ET + woven fiber (WF) + CR. The specimens were stored in physiological serum at 37oC for 24 hours. Later, a compressive force was applied by means of a universal testing machine at 1 mm/min speed, parallel to the long axis of the teeth until the fracture occurred. After mechanical test three types of fractures were classified: 1) pulp chamber floor; 2) cusp; 3) pulp chamber floor and cusp. The means of results (N) followed by the same letter do not represent a statistical difference by ANOVA and Tukey (p<0,05): G1 (4960)a, G2 (1926. 20)b, G3 (612. 84)c, G4(1813. 9)b, G5 (2024)b, G6 (1879)b. In the analysis of qualitative variables of G5 and G6, there was a tendency to fracture in the pulp chamber floor and cusp not benefic to restore the tooth integrity. It is possible conclude that inserting the unidirectional or woven glass fibers into MOD cavity preparations and restored with composite resin the fracture strength is similar to that obtained in molars filled with composite resin only.