Undersized Implant Site Preparation to Enhance Primary Stability in Computer-Guided Flapless Surgery: Sequential Drilling Protocol

Abstract

Achieving primary implant stability in areas with poor bone density is often challenging for the clinician. This modified surgical protocol might be beneficial in such situations in computer-guided surgery. The purpose of the present clinical application is to give the clinician the sequence and steps for undersized implant site preparation in areas with poor bone density. After an evaluation of the bone density with the software on the CT scan, the implant site is prepared with drilling while remaining undersized. The implant is then inserted by setting the torque of the implant motor to 35 N-cm. When the desired torque is achieved, the distance between the implant and the bushing is measured. The rule suggests that if more than 3 mm are missing at the lower limit, it is advisable to remove the implant and prepare again with the next diameter drill, if it is less than 3 mm it is possible to use the method of self-tapping directly with the implant. The surgical drilling protocol allows the clinician to limit the number of drills and to use the implant mounter as a reference point when it stops at a certain distance from the bushing. The results of this clinical application suggest that undersized implant site preparations may help enhance primary implant stability in computer-guided surgery and that there are significant correlations among bone density, maximum insertion torque, implant mounter and drilling kit.