Navigated Flapless Transmucosal Implant Placement in the Mandible: A Pilot Study in 20 Patients

Purpose: The aim of this study was to assess whether navigated flapless transmucosal implant bed preparation allows placement of dental implants in edentulous mandibles. Materials and Methods: Each patient was scheduled to receive 4 screw-shaped Ankylos (Dentsply Friadent) implants in the interforaminal region. The VISIT navigation system was used for guided drilling. The mucosa was penetrated without flap elevation. The study protocol did not allow direct visualization of the bone surface during surgery. Data analysis included computed measurements on pre- and postoperative computerized tomographic (CT) images. Results: Twenty patients with fully edentulous mandibles (14 male, 6 female) were included in the study. Computer-based planning for 80 implants was performed intraoperatively. Two implants (2.5%) were not primarily stable because of buccal bone fenestration, which occurred because of uncontrollable shifting of the dental implant drill. These implants were immediately removed. Postoperative CT image evaluation revealed a mean deviation of 0.7 mm in all directions. Conclusions: Navigated flapless transmucosal interforaminal implant placement was found to be a precise, predictable, safe procedure in patients with smooth wide regular mandibular ridges. The technique was less accurate and more complicated in areas where irregular bone existed. (Clinical Trial) Keywords: computer-aided navigation, flapless surgery, transmucosal implant