The objective of this study was to determine the influence of height and thickness of the one wall remaining coronal tooth structure on the fracture resistance of an endodontically treated root with resin abutment build-up using resin composite and fiber-reinforced resin composite post. Static and dynamic fracture tests were performed by placing the remaining tooth wall on the tensile side and applying loads at an angle of 30° from the tooth axis. Superior static fracture resistance was observed when the wall remaining on the tooth had a height and thickness greater than 1.0 mm. The dynamic fatigue test showed high loading capacity or fracture resistance in specimens with large height and thickness. The dynamic fatigue test showed the influence of the remaining tooth structure on fracture resistance clearly. In conclusion, the static and dynamic fracture resistances increased with the height and thickness of the one wall remaining tooth structure.
Keywords: Dynamic fatigue; Endodontically treated tooth; Fiber post; Fracture strength; Remaining coronal tooth.