Influence of ferrule preparation with or without glass fiber post on fracture resistance of endodontically treated teeth

Objective: this study evaluated the effect of ferrule preparation (fp) on the fracture resistance of endodontically treated teeth,restored with composite resin cores with or without glass fiber posts. material and methods: forty-four bovine teeth were sectioned 19 or 17 mm (2 mm ferrule) from the apex,endodontically treated and assigned to four groups (n = 11): group 1: fp and post; group 2: fp and without post; group 3: without fp and with post; group 4: without fp and without post. all specimens were restored with composite resin core and metal crown. specimens were subjected to fracture resistance testing in a universal testing machine at a crosshead speed of 0.5 mm/min. the data were analyzed by two-way anova and tukey's tests (α=0.05). results: the mean fracture resistance values were as follows: group 1: 573.3 n; group 2: 552.5 n; group 3: 275.3 n; group 4: 258.6 n. significantly higher fracture resistance was found for the groups with fp (p<0.001). conclusion: there was no statistically significant interaction between the fp and post factors (p = 0.954). the ferrule preparation increased the fracture resistance of endodontically treated teeth. however,the use of glass fiber post showed no significant influence on the fracture resistance.