The influence of platform switching on the biomechanical aspects of the implant-abutment system. A three dimensional finite element study.

OBJECTIVE

To evaluate the biomechanical scenario of platform switching geometric implant-abutment configuration relative to standard configurations by means of finite element analysis.

STUDY DESIGN

A 3D Finite Element Analysis (FEA) was performed on 3 different implant-abutment configurations: a 3.8 mm implant with a matching diameter abutment (Standard Control Design, SCD), a 5.5 mm implant with matching diameter abutment (Wider Control Design, WCD), and a 5.5mm implant with a 3.8 mm abutment (Experimental Design, ED). All the different experimental groups were discretized to over 60000 elements and 100000 nodes, and 130N vertical (axial) and 90N horizontal loads were applied on the coronal portion of the abutment. Von Mises stresses were evaluated and maximum and minimum values were acquired for each implant-abutment configuration.

RESULTS

The load-induced Von Mises stress (maximum to minumum ranges) on the implant ranged from 150 MPa to 58 Pa (SCD); 45 MPa to 55 Pa (WCD); 190 MPa to 64 Pa (ED). The Von Mises stress on the abutment ranged from 150 MPa to 52 MPa (SCD); 70 MPa to 55 MPa (WCD), and 85 MPa to 42 MPa respectively (ED). The maximum stresses transmitted from the implant-abutment system to the cortical and trabecular bone were 67 Pa and 52 MPa (SCD); 54 Pa and 27 MPa (WCD); 64 Pa and 42 MPa (ED), respectively. When the implant body was evaluated for stresses, a substantial decrease in their levels were observed at the threaded implant region due to the diametral mismatch between implant and abutment for the ED configuration.

CONCLUSION

The platform switching configuration led to not only to a relative decrease in stress levels compared to narrow and wide standard configurations, but also to a notable stress field shift from bone towards the implant system, potentially resulting in lower crestal bone overloading.