Stress distribution of three different rubber dam clamp materials on natural tooth and endodontically access prepared tooth using finite element method

Introduction: This study aimed to compare the stress distribution generated by metal, polyethylene ketone (PEEK), and polypropylene (PP)/natural rubber (NR) clamps on a sound tooth and teeth with various endodontic access cavity preparations using finite element (FE) analysis.Materials and Methods: A human mandibular first molar and dental clamps were scanned using micro-computed tomography (micro-CT) to create FE models. The traditional access cavity (TAC) design and periodontal structures were modeled using computer-aided design (CAD) software, resulting in five tooth models: Model 1 (sound tooth), Model 2 (tooth with TAC), Model 3 (tooth with TAC and three remaining walls), Model 4 (tooth with TAC and two remaining walls), and Model 5 (tooth with TAC, two remaining walls, and one cusp reduction). The clamps were guided past the height of contour of the tooth, ensuring all four beaks were seated at the cementoenamel junction (CEJ). The maximum equivalent Von Mises (EQV) stress and strain were recorded in the enamel, dentin and bone.Results: The EQV stress was consistently higher in the enamel than in the dentin, with the distolingual (DL) site experiencing the highest stress across all models. Among the clamps, the metal clamp generated the highest EQV stress, which was 66.49–77.77% higher than PEEK and 73.30–90.63% higher than PP/NR. Additionally, PEEK generated 7.42–61.24% higher stress than PP/NR. The maximum EQV stress was greater in teeth with access cavity preparations than in sound teeth, and as more tooth structure was lost, the EQV stress on the enamel increased.Conclusion: The EQV stress induced by dental clamps primarily affected the enamel more than the dentin. The PP/NR clamp generated the lowest stress, suggesting it may serve as a viable alternative in dental procedures. Additionally, greater tooth structure loss resulted in higher EQV stress on the enamel.