Effect of thermomechanical cycling on canines after endodontical treatment and restoration with prefabricated carbon fiber or cast metallic posts

• Grant number: 09/14444-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2009
• End date: December 31, 2011
• Field of knowledge: Health Sciences - Dentistry - Dental Clinics
• Principal Investigator: Renata Cristina Silveira Rodrigues Ferracioli
• Grantee: Rafaela Soares Spolaor
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

The restoration of endodontically treated teeth continues to generate doubts and discussions for clinicians and researchers. Intraradicular prefabricated posts and metallic cast cores have been empirically and subjetically indicated for many times, without knowledge of the biomechanical and clinical principles that determine the correct indication and selection of posts and cores. The main reason to use posts is the possibility of coronary reconstruction using intra-radicular retention for that. Among the options, the metallic cast cores, the prefabricated metallic posts and the non-metallic prefabricated posts are highlighted. The first alternative to metallic posts, cast or pre-fabricated ones, were the carbon fiber posts, that arose around 1990. These posts have elastic modulus closest to those of dentin in comparison to metallic posts. Despite some previous studies, it is evident that the professionals still have doubts regarding the restoration of endodontically treated teeth, and so, this study tested the hypothesis that there is significant difference in the resistance of these teeth after mechanical and thermal cycling for different time periods when restored with different posts systems. Aditionally will be verified if there is significant difference in the infiltration after a total cycling period. The posts systems used will be: carbon fiber and metallic cast core. These posts will be luted with dual resin cement in tooth roots and over that metallic total crowns will be placed. After the crowns luting, the samples will be submitted to the thermomechanical cycling test. Over 500,000 cycles will be carried, and at each 100,000 cycles the samples will be visually verified for integrity, as in clinical practice. After the test accomplishment, the samples will be placed in fucsin basic solution for 24 hours; after this period will be included, cutted and the leakage areas will be analyzed under optical microscopy. The obtained data will be statistically analyzed.