Accuracy assessment of computer-assisted flapless implant placement in partial edentulism.

AIM To assess the accuracy of implants placed flapless by a stereolithographic template in partially edentulous patients. MATERIAL AND METHODS Eight patients, requiring two to four implants (maxilla or mandible), were consecutively recruited. Radiographical data were obtained by means of a cone beam or a multi-slice CT scan and imported in a software program. Implants (n=21) were planned in a virtual environment, leading to the manufacture of one stereolithographic template per patient to guide the implant placement in a one-stage flapless procedure. A postoperative cone beam CT was performed to calculate the difference between virtual implant (n=21) positions in the preoperative planning and postoperative situation. RESULTS A mean angular deviation of 2.7 degrees (range 0.4-8, SD 1.9), with a mean deviation at the apex of 1.0 mm (range 0.2-3.0, SD 0.7), was observed. If one patient, a dropout because of non-conformity with the protocol, was excluded, the angular deviation was reduced to 2.2 degrees (range 0.6-3.9, SD 1.1), and the apical deviation to 0.9 mm (range 0.2-1.8). CONCLUSION Based on this limited patient population, a flapless implant installation appears to be a useful procedure even when based on accurate and reliable 3D CT-based image data and a dedicated implant planning software.