Influência da transfixação horizontal por um pino de fibra de vidro na resistência à fratura de molares endodonticamente tratados

• Autor(a) principal: Beltrão, Maria Cecilia Gomes
• Data de Publicação: 2005
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional PUCRS
• Texto Completo: http://hdl.handle.net/10923/424
• topic: ODONTOLOGIA; ENDODONTIA; RESINAS COMPOSTAS; MATERIAIS DENTÁRIOS; RESISTÊNCIA DOS MATERIAIS (ODONTOLOGIA)

The purpose of this study was to assess the effect of a horizontally transfixed fiber glass post on the fracture resistance of molar teeth endodontically treated with MOD preparations, restored or not with composite resin. Seventy-five sound human third molars were extracted and mounted on acrylic resin blocks and were randomly assigned to five groups (n=15). In Group A, the teeth remained sound (control). Groups B, C, D and E, treated endodontically, were subjected to the following procedures: Group B – MOD preparation, group C – MOD preparation and transfixed post, group C – MOD preparation and resin composite restoration, group E – MOD preparation, transfixed post, and composite resin. The samples were stored in physiological serum at 37ºC for 24 hours. Later, a compressive force was applied parallely to the long axis of the teeth to fracture, performed by means of a universal testing machine (EMIC DL-2000) at 1 mm/min speed. The means in Newtons (N) of the results (standard deviation) followed by the same letter did not show a statistic difference for ANOVA and Tukey, p=0. 05: Group A = 4289. 8 (± 1128. 9)a, Group B = 549. 6 (± 120. 7)b, Group C = 1474. 8 (± 338. 1)c, Group D = 1224. 7 (± 236. 0)c, Group E = 2645. 4 (± 675. 1)d. In the analysis of qualitative variables, cusp fracture prevailed in 56%, a recoverable diagnosis was found in all groups, except for Group C, and the palatal cusp preparation prevailed in all Groups, except for Group A. It was concluded that a fiber glass post transfixed horizontally to the walls of a MOD cavity significantly increased fracture resistance, and when associated to the composite resin restoration, it established a fracture pattern compatible with the recovery of the dental specimen.