Abstract
The goal of the study is to assess the effects of hole preparation and the frequency of screw placement on pullout out resistance and insertonal torque of the pedicle screw. Pedicle screw (5 mm, 6 mm e 7 mm the outside diameter) will be used in the study. The polyurethane, wood and bovine bones will be used as fixation materials. The implants will be inserted on the materials until three …