Aslan, T.Sagsen, B.Er, O.Ustun, Y.Cinar, F.2024-06-122024-06-1220181119-3077https://doi.org/10.4103/njcp.njcp_330_17https://hdl.handle.net/20.500.14551/21071Objective: 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 (a = 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.en10.4103/njcp.njcp_330_17info:eu-repo/semantics/closedAccessFiber PostFracture ResistanceHorizontal PostPolyethylene FiberTooth ReinforcingGlass-Fiber PostsIn-VitroRestoration TechniquesPolyethylene FiberDifferent LengthsFilled TeethStrengthMolarsPremolarsCompositeArticle216795800Q4WOS:0004390447000192-s2.0-8504848189529888730Q3