Measurement of the stress and deflection that occurs at the surrounding bone and on the mini screws which are made of different materials placed at the mandibular bukkal shelf region in different locations and DUE to forces at different directions

The aim of this study is to evaluate the stress distribution and deflection that occurs in the mini screw and bone as a result of placing mini screws produced from two different materials in different positions on the buccal shelf area of the mandible and applying different amounts of force in different directions. In this research, stainless steel and titanium were used as screw material. The screws were placed in 2 different locations such as mesial and distal to the second molar on the mandibular buccal shelf area with an angle of 70 ° with the occlusal plane. 4 different FEM models were created. In this manner 200, 300, 400, 500 gr forces were applied to the mini screw in each model in either sagittal or lingual directions, parallel or perpendicular to the occlusal plane. In the light of the data obtained from the study, it was aimed to determine the most suitable screw material and location for buccal shelf area. According to the results of our study, after the application of the force the greatest stress accumulation on the mini-screw was observed in the neck region of the mini-screw. In addition, the amount of stress increased with increasing force. Besides, it was observed that the amount of stress accumulated on stainless steel mini screws was lower than on titanium mini screws. On the other hand, it was found that the amount of stress decreased with increasing cortical bone thickness. According to the other results of our study, bending occurred in the mini screws depending on the magnitude of the applied force. The amount of bending increased with increasing force. In addition, the amount of bending observed in stainless steel mini screws was found to be lower than in titanium screws. Besides, a decrease in the amount of bending occurred with increasing cortical bone thickness.