Does ferrule thickness influence resistance to fracture of endodontically treated teeth?

BACKGROUND: Teeth with severe crown destruction and endodontically treated may or may not present a circular strip of dental tissue located in the cervical region called ferrule. AIMS: The aims of this study were to evaluate ferrule thickness influence on endodontically treated teeth (ETT) resistance to fracture. MATERIALS AND METHODS: A total of 30 bovine incisor teeth were selected, endodontically treated and randomly distributed, according to the ferrule thickness: G1- no ferrule, G2 – 1 mm, and G3 – 2 mm. All the teeth were restored with prefabricated posts and composite resin. Resistance to fracture was established as the compression strength at 45° tilt at the lingual surface of the crown. STATISTICAL ANALYSIS USED: Data were analyzed using ANOVA and Tukey's test. RESULTS: Resistance to fracture of G1 and G2 were significantly higher than that of G3 (P < 0.001). The pattern of fracture, common to all groups, occurred at the composite resin on the coronary portions. CONCLUSION: Ferrule thickness can influence the resistance to fracture of ETT.