Stress Distribution in a Mandibular Kennedy Class I with Bilateral Implant-Assisted Removable Partial Denture: A Finite Element Analysis

Objectives: This study evaluated the dental and alveolar bone stress distribution of a mandibular Kennedy Class I restored with a bilateral implant-assisted removable partial denture (IARPD) compared with a conventional removable partial denture (CRPD) through the application of finite element analysis (FEA). Methods: Kennedy Class I plaster models were made, including teeth from the lower left first premolar and lower right canine. The models were scanned, resin-based replicated and digitized. Using Solidworks software, internal hexagonal implants (10 mm × 4 mm) were virtually placed at the level of the first molars. Each model was grouped into a unit, and a load of 200 N was applied, simulating masticatory forces. Von Mises stress distributions were calculated via FEA for the vertical, diagonal and combined forces. Results: In the IARPD, the stress generated in the alveolar bone by the vertical (4.2 Mpa), diagonal (12.2 MPa) and combined forces (12.3 MPa) was lower than that of the CRPD (7 MPa, 26.3 MPa and 32 MPa, respectively). Similarly, at the lower central incisor, the IARPD generated less stress than the CRPD due to the action of the vertical, diagonal and combined forces. Conclusions: Our preliminary data suggest that bilateral implant placement may result in less stress on bone and teeth during rehabilitation with a Kennedy Class I IARPD, with different orientations of the forces applied.