Three Dimensional Finite Element Analysis to Evaluate Stress Distribution around Implant Retained Mandibular Overdenture Using Two Different Attachment Systems

Abstract

Statement of the problem: A key factor for the success or failure of dental implants is the manner in which stresses are transferred to surrounding bone. Purpose of the study: The aim of this study was to create complete three- dimensional finite element models of mandibles with their implant-retained over dentures (IRO) to evaluate the influence of two different attachment systems on stress distribution at implant bone level. Methods: The geometries of six edentulous mandibles with their IRO were generated from computed tomography scans. Two implants (3.75mm x 13mm) with ball abutments and locator attachments were placed in the canine areas of each edentulous mandible. Two models FEM (A) and FEM (B) were used for the load application and analysis. A vertical (100 N) and oblique (100 N) loads were applied to each of the above models respectively at the premolar/molar region of the over dentures. These two different models were analyzed by a finite element program (Solid Works) and displayed using Von misses stress patterns. Results: The results showed that the maximum stress values were seen at the crestal bone around all implants. Lower stress values were recorded for the locator attachment at all measured aspects. Vertical loading was associated with higher stress values and working side implants were showing greater stress magnitudes. Conclusion: Within the limitations of this study, locator attachment may be an adequate alternative to ball attachment as it reduces stresses on the implant body and supporting structures for implant-retained over dentures.