ABSTRACT
Conventional osteotomy techniques can, in some cases, induce higher stress on bone during implant insertion as a result of higher torque. The aim of the present study was to evaluate and compare the stress exerted on the underlying osseous tissues during the insertion of a tapered implant using different osteotomy techniques through a dynamic finite element analysis which has been widely applied to study biomedical problems through computer-aided software. In three different types of osteotomy techniques, namely conventional (B1), bone tap (B2), and countersink (B3), five models and implants designed per technique were prepared, implant insertion was simulated, and stress exerted by the implant during each was evaluated. Comparison of stress scores on the cortical and cancellous bone at different time points and time intervals from initiation of insertion to the final placement of the implant was made. There was a highly statistically significant difference between B1 and B2 (p = 0.0001) and B2 and B3 (p = 0.0001) groups. In contrast, there was no statistically significant difference in the stress scores between B1 and B3 (p = 0.3080) groups at all time points of implant placement. Overall, a highly significant difference was observed between the stresses exerted in each technique. Within the limitations of our study, bone tap significantly exerted lesser stresses on the entire bone than conventional and countersink type of osteotomy procedures. Considering the stress distribution at the crestal region, the countersink showed lower values in comparison to others.
ABSTRACT
AIM: This study aimed to compare the von Mises stress distribution and deformation on the implant, abutment, and abutment screw using metal-ceramic, zirconia, polyether ether ketone (PEEK), and Trinia as prosthetic materials for full-mouth cement-retained implant prosthesis using finite element analysis. MATERIALS AND METHODS: Four, 3-dimensional mandibular models were designed using Solidworks software. Six conical implants of 4.5 × 11.5 mm, with an internal hexagonal abutment, were fabricated and placed. The physical properties of the implant components, bone, and crowns were simulated to mesh the three-dimensional finite element models. The bite was recorded, and various contact points were marked, on which 50 N loads were applied. The von Mises stress distribution and resultant deformation were analyzed using the finite element method. RESULTS: Higher stress distribution was recorded on the implants, abutments, and abutment screws when zirconia and PEEK prosthesis were used in comparison to metal-ceramic and Trinia. In consideration of deformation, zirconia and Trinia resulted in higher deformation of the implant assembly, abutment, and abutment screw when compared to metal-ceramic and PEEK prosthesis. Anterior implants showed a higher deformation and stress distribution when compared to posterior implants for all four prosthetic materials. CONCLUSION: Within the limitations of the study, metal-ceramic and Trinia showed less stress distribution, while metal-ceramic and PEEK exhibited less deformation on implant and its components. Hence in future, Trinia and PEEK along with metal-ceramic can be promising prosthetic materials of choice in full-mouth rehabilitation with implants. CLINICAL SIGNIFICANCE: Considering the deformation and stress distribution on the implant and its components, the selection of prosthetic material in full-mouth rehabilitation has always been a challenge. Findings of the abovementioned cross-sectional observational study could give an overall insight into materials such as metal-ceramic and Trinia as materials of choice, which can provide a basis for future clinical trials.
