Fracture resistance of endodontically treated maxillary premolars with a longer single post and shorter double posts of different sizes: An in vitro study

Aim: The aim of this study was to determine if there is any difference in fracture resistance between different post sizes and lengths when more than one post is involved. Materials and Methods: Thirty extracted maxillary first premolars were endodontically treated and divided into three groups: In Group 1 (control group), no post space preparation was conducted and access cavities were restored with composite; in Group 2 (single post), post space preparation of 10mm was carried out only in one of the canals; and in Group 3 (double post), post space preparation of 5mm was conducted in both the canals. Appropriately sized glass fiber posts were cemented in Groups 2 and 3 followed by core buildup. The fracture resistance of the specimen was measured using a universal testing machine and the data analyzed. The mean fracture resistance values of the three groups were compared applying one-way analysis of variance (ANOVA) followed by post hoc Tukey's test. The data were analyzed using Statistical Package for the Social Sciences software program, version 15.0. South Asia, Bangalore. Results: The control group had a significantly lower fracture resistance value as compared to Groups 2 and 3. No statistically significant difference was observed in the fracture resistance between Groups 2 and 3. Conclusions: No significant difference was observed between the fracture resistance of endodontically treated maxillary first premolars restored with size 3 single post of longer length and size 1 double posts of shorter lengths.