Effect of Truss Access and Artificial Truss Restoration on the Fracture Resistance of Endodontically Treated Mandibular First Molars

Abstract

IntroductionThis study evaluated the effects of traditional and truss access cavity preparations in addition to artificial truss restoration on the fracture resistance of endodontically treated mandibular molars. MethodsA total of 66 recently extracted, intact mandibular first molars were collected from patients between 20 and 45 years of age. After the preparation of a mesio-occluso-distal cavity in all teeth, the teeth were randomly grouped into the following 4 groups according to the access cavity design: traditional access cavity, artificial truss restoration, truss access cavity, and control groups. Endodontic access cavities were performed in the experimental groups according to each treatment modality followed by instrumentation, irrigation, and obturation. After composite restoration, the teeth were subjected to a vertical occlusal force until fracture occurred. The data were statistically analyzed, and the fracture patterns were evaluated. ResultsFirst, a 1-way analysis of variance test analysis of the fracture resistance of the experimental groups showed nonsignificant differences among groups (P > .05). Second, the data were statistically analyzed using the Student t test to compare the fracture resistance of each experimental group with that in the control group. The control group had statistically significantly higher mean values for fracture resistance than the traditional access group and the artificial truss restoration group (P < .05). No statistically significant difference was recorded in the fracture resistance between the control group and the truss access cavity group (P > .05). ConclusionsThe truss access cavity preparation improved the fracture resistance of endodontically treated teeth with mesio-occluso-distal cavities, whereas the artificial truss restoration did not improve it.