Evaluation of fracture resistance in root canal‑treated teeth restored using different techniques

Abstract

Objective: This study aimed to evaluate the effects of different coronal restoration techniques on fracture resistance of root canal‑treated mandibular premolars with mesio‑occluso‑distal (MOD) cavities.

Materials and Methods: A total of 105 mandibular premolars were selected and randomly distributed into seven groups (n = 15). MOD cavities were prepared except the control group. Root canal treatments were performed. Each tooth was embedded in acrylic resin. Groups were classified as follows; G1: intact teeth (control), G2: unfilled MOD cavity, G3: MOD + composite resin, G4: 10‑mm‑long fiber post + composite resin, G5: 5‑mm‑long fiber post + composite resin, G6: Ribbond in the occlusal surface + composite resin, and G7: horizontal fiber post + composite resin. Specimens were loaded using a universal testing machine until fracture occurs. Fracture loads were recorded and statistical interpretations were made (α = 0.05).

Results: In Groups 1, 6, and 7, the greatest fracture resistance was shown and there were no significant differences among these groups (P > 0.05). No significant differences were detected among the Groups 3, 4, and 5 (P > 0.05), whereas the fracture resistances of Groups 1, 6, and 7 were significantly greater than these three groups (P < 0.05). Group 2 had the lowest fracture resistance of all groups (P < 0.05).

Conclusion: Usage of horizontal post or occlusal Ribbond usage increased the fracture resistance of root canal‑treated premolars with MOD cavities.

Keywords: Fiber post, fracture resistance, horizontal post, polyethylene fiber, tooth reinforcing