Finite Element Analysis of Different Bone Substitutes in the Bone Defects Around Dental Implants

PURPOSE: To evaluate the distribution of stress and strain for the evaluation of implant and graft stability at each stage before stabilization of the graft is achieved after implantation was performed. MATERIALS AND METHODS: Dembone (Pacific Coast Tissue Bank, Los Angeles, CA), Bio-Oss (Geistlich Pharma, Wolhusen, Switzerland), particulate dentin, and plaster of Paris were used to fill bone defects. The distribution of stress was compared in the mandible and maxilla, between vertical load and load applied at 30 degrees angle, and according to time, with 3 different graft materials. RESULTS: Stress occurred more when it was applied at an angle, rather than applied vertically. Stress was relatively high immediately after implantation, and particulate dentin-plaster of Paris showed larger mechanical properties and lower stress distribution overall. The largest stress distribution was shown when stress was applied at an angle when demineralized freeze-dried bone was used. The pattern of stress distribution was different according to differences in the mechanical properties of implants. CONCLUSION: Caution is needed not to apply stress at an angle immediately after implantation. Differences of stress were reduced with time as the implant became stabilized.