New method for the placement of miniplates in mouth without surgical applications: Evaluation of the application with 3-dimensional finite element stress analysis

Aim of the study is to evaluate the stresses on the different temporary anchorage devices (TAD) and around the bone with 3-dimensional finite element analysis, when forces are applied on mini-screw and mini-plate. The hypothesis of the study is; mini-implant rings (MIR) usage as a platform for the mini-plates, affect the forces applied to the surrounding cortical bone. 3-dimensional bone models were created for four different TAD designs. Scenarios: (1) mini-screw, (2) mini-screw with MIR (1 mm), (3) mini-plate, (4) mini-plate on MIR (2 mm) platforms. Scenario 1 and 2 were placed on 30x30x13.5 mm bone block model (1.5 mm cortical, 12 mm trabecular bone), scenario 3 and 4 were placed on 48x30x13.5 mm block. Minimum and maximum principal stresses are valuable for bone stress analysis. Minimum principal stresses on the surface of the cortical bone around the neck of the mini-screw are 3.08 MPa for scenario 1 and 0.04 MPa for scenario 2. Maximum principal stresses on the neck region are 3.38 MPa for scenario 1 and 0.03 MPa for scenario 2. Minimum principal stresses on the surface of the cortical bone around the neck of the mini-screws are 0.45-0.48 MPa for scenario 3 and almost 0 MPa for scenario 4. Maximum principal stresses on the neck region are 0.42-0.48 MPa for scenario 3 and 0.22-0.22 MPa for scenario 4. As a result, it can be said that usage of MIR is an effective application to reduce the stresses on the surrounding bone structure together with generally accepted TADs.