Effect of Different Implant-Abutment Mismatches on Stress Distribution: A 3-Dimensional Finite Element Study.

Platform-switching reduces peri-implant marginal bone loss (MBL). The aim of this study was to compare the effect of platform-switching on stress within crestal bone using different implant-abutment mismatches (0.65 and 1 mm) under 2 different vertical loads (30 N vs 200 N) for implants placed in posterior jaw sites. Three-dimensional modeling software was used for an implant with a diameter of 4.5 mm and length of 13 mm. Molars were modeled using computerized tomography images of bone density in human maxilla (D3 bone) and mandible (D2 bone). Collected data were analyzed using CATIA software. In posterior mandible, stress of 30 N force with platform mismatches of 0.65 or 1 mm were 2.920 and 2.440 MPa respectively. Using 200 N force, values increased to 19.44 and 16.30 MPa. In posterior maxilla and 30 N force, stresses with mismatches of 0.65 and 1 mm were 3.77 and 3.18 MPa, respectively, increasing to 25.14 and 20.17 MPa with 200 N force. The effect can be predicted to be greatest as the mismatch increases with implants placed into lower quality bone (posterior maxilla with D3 quality).