IADR Abstract Archives
A Non-Linear Finite Element Evaluation of Two Clasp Designs for Bilateral Distal Extension Mandibular Removable Partial Denture
Objectives: This finite element analysis study compared the stress distribution between two types of stress breaker clasp designs for bilateral distal-extension removable partial denture which were the reverse circlet clasp and the RPI clasp. The stress distribution on abutment tooth, periodontal ligament, and cortical bone were analyzed with three-dimensional non-linear finite element analysis model.
Methods: The 3D models of mandible and bilateral distal extension removable partial dentures were constructed from the cone beam computed tomography scanning on a patient’s mandible which remaining teeth from 35-45. The Mandibular model consisted of residual bone, remained teeth and periodontal ligament of remained teeth. The removable partial denture had RPI clasp on tooth 35 and reverse circlet clasp on tooth 45. The action of reverse circlet clasp and RPI clasp of bilateral distal-extension removable partial denture were analyzed by nonlinear three dimensional finite element analysis with unilateral load of 200 N. The stress distribution and concentration to supporting bone, periodontal ligament and abutment tooth were calculated.
Results: Under vertical load at the distal-extension denture, the stress distribution was observed among 2 clasp designs. The RPI clasp exhibited lower stress concentration and distribution on residual ridge, periodontal ligament and abutment tooth than the reverse circlet clasp.
Conclusions: For bilateral distal extension removable partial denture design, the RPI clasp was more favorable choice in comparison to the reverse circlet clasp. From the result of this study, this claps design exhibited a mechanical efficacy by having better stress distribution on both abutment and surrounding soft tissue.
Methods: The 3D models of mandible and bilateral distal extension removable partial dentures were constructed from the cone beam computed tomography scanning on a patient’s mandible which remaining teeth from 35-45. The Mandibular model consisted of residual bone, remained teeth and periodontal ligament of remained teeth. The removable partial denture had RPI clasp on tooth 35 and reverse circlet clasp on tooth 45. The action of reverse circlet clasp and RPI clasp of bilateral distal-extension removable partial denture were analyzed by nonlinear three dimensional finite element analysis with unilateral load of 200 N. The stress distribution and concentration to supporting bone, periodontal ligament and abutment tooth were calculated.
Results: Under vertical load at the distal-extension denture, the stress distribution was observed among 2 clasp designs. The RPI clasp exhibited lower stress concentration and distribution on residual ridge, periodontal ligament and abutment tooth than the reverse circlet clasp.
Conclusions: For bilateral distal extension removable partial denture design, the RPI clasp was more favorable choice in comparison to the reverse circlet clasp. From the result of this study, this claps design exhibited a mechanical efficacy by having better stress distribution on both abutment and surrounding soft tissue.