Comparative biomechanical analyses for kennedy’s class-I cast partial denture using acrylic denture base with Co-Cr I bar and nylon denture base with nylon retentive clasp-A 3D finite element study

Abstract

Introduction: The goal of present PRPD is to optimize esthetics with denture design that ensures minimal invasion to the remaining oral tissues, since the function of an PRPD is affected by physical properties of direct retainers. A comparative 3-D Finite Element (FE) stress analysis for mandibular Kennedy’s class-I situation using two different denture base and direct retainer material on distal abutment was done Method: FE models were developed, with simulated alveolar bone, mucosa, abutments, periodontal ligaments, framework and artificial teeth in the models. The 2 FE models, Model A having PMMA denture base and Co-Cr gingival approaching clasp and Model B having nylon denture base and retentive clasp made up of nylon only were developed. Structural analysis for two designs was carried out using ANSYS FEA software. Results: During analysis static distributed load of 150N over artificial teeth vertically and 45ᵒ diagonally was applied. The stresses and deformation produced in assembly were evaluated Structural analysis results were analyzed for various supporting structures. The two designs showed considerable differences in stresses and displacement developed in supporting structures. Cast partial denture with nylon direct retainer and denture base showed greater stresses and displacement than acrylic denture base and Co-Cr clasp on diagonal loading whereas on vertical loading it showed almost similar displacement but slightly greater stresses. Conclusion: The results of this study suggest the use of nylon as denture base and direct retainer in esthetic region for class I situation as it generate favorable biomechanical stress, being all values are under the physiologic limit.