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case study_ flapless implant placement I then rotated back and forth around the peg to register and calibrate the drill axis. The system then prompts us to calibrate the drill. The initial precision point drill was then placed onto the handpiece and calibrated by placing the drill tip into the dimple present at the center of the target on the JawTag (Fig. 3). Once the drill tip was calibrated, it then became visible on the monitor against the CT image when it is placed into the surgical field. Our next step was to verify the drill tip posi- tion. This was done easily by placing the tip of the bur on a landmark in the jaw to verify ac- curacy of its positioning. In our case, the tip of the drill was verified by placing it on the cusp tip of the neighboring tooth 2.4 (13). The drill was then brought to the surgical site (Fig. 4), and the navigated drilling screen comes up, which shows a target view and cross-sectional views of the CT images with the drill image visualized in its real-time position (Fig. 5). The target and cross-sectional views allow you to position the drill into the ideal digitally planned implant position based on the live view of the drill over the CT images. The drilling process was started with a precision drill to punch a dimple into the bone and give us a soft-tissue bleeding point. The bleeding point was then used as a marker to remove a 4 mm diameter of crestal gingiva with a tissue punch. The Straumann pilot drill was then calibrated and verified on the handpiece. The 2.2 mm pilot drill was then used to drill at 800 rpm to about 7 mm into the osteotomy using the live navigation to guide us into the digitally planned position. The second 2.8 mm drill in the Straumann Bone Level Tapered im- plant protocol was calibrated, verified and live navigated to the desired position at a depth of 7 mm into the osteotomy. The drills were now switched to the Hiossen CAS-KIT drills to allow removal of the cortical bone at the floor of the sinus without damaging the Schneiderian membrane. The CAS-Drill tip has an inverse conical shape that forms conical bone chip as it drills to allow it to safely elevate the sinus membrane without perforating it. The bone particles formed when drilling dis- charge upward producing a membrane auto- lift function. The Hiossen CAS 3.3 mm drill was used with an 8 mm stopper as a backup to prevent us from forcefully pushing too deep into the sinus. The CAS drill was calibrated and verified and then live navigated to access the sinus membrane. Once the membrane was exposed through the osteotomy, it was elevated using hydraulic pressure with the CAS-Kit Membrane Lifter and sterile saline. Cortical allograft chips were then gently pushed into the void created from the membrane elevation. The jaw stent was re- moved, and the implant was placed through the osteotomy with direct vision. The Straumann Bone Level Tapered 4.1 mm x 10 mm implant was placed with 50 Ncm of primary stability. A healing abutment was then hand-torqued in place (Fig. 6). A postoperative peri-apical radiograph (Fig. 7) was taken to assess the implant placement. The implant can also be live navigated into place; however, it needs to be calibrated by touching the tip of the implant over the JawTag dimple, and because of the risk of contamina- tion, we chose to place it with direct vision. The company recommends placing a sterile piece of nylon over the dimple when calibrating the implant to keep the conditions sterile. Because of the flapless live-guided Navident protocol, we were able to release the patient with no sutures required and minimal trauma to the site. The patient was prescribed anti- inflammatory analgesics and placed on a 7-day antiobiotic course. Her healing was uneventful with minimal discomfort to the area. _Conclusion Computer-guided placement of dental im- plants is significantly more accurate than free hand surgery.6 In areas of complex anatomy, computer-guided navigational surgery is su- perior to conventional implant surgery when it comes to preventing iatrogenic injuries.7 This technology can contribute to considerable improvement in quality and accuracy of dental implant placement. The live real-time view of the exact position of the drill minimizes the potential risk of dam- age to critical anatomic structures.8 The optical tracking system seems to be more accurate and have more flexibility during surgery but does require more training to develop hand-eye coordination for using the system.9 However, once mastered, this new system can improve on accuracy of surgery, reduce surgeon anxi- ety, improve patient confidence and work as a powerful marketing tool for your practice. References available upon request from the publisher._ _about the author Dr. Naheed Mohamed received his bachelor of science degree from the University of Toronto with honors. After a year of peri- odontal research at Mount Sinai Hospital, he attended dental school at Boston Uni- versity and completed his doctor of dental medicine degree. Graduating from dental school magna cum laude and with the American Academy of Periodontology Dental Student of the Year Award for achievement in periodontics, Mohamed further pursued his studies at Case Western Reserve University in Cleveland to complete his specialty train- ing in periodontics. During his residency, he pioneered research in an autologous material blood-derived called platelet-rich fibrin and its numerous clinical applications, earning his master’s degree. Mohamed is a board-certified special- ist in the United States and Canada, attaining his dip- lomate status by the Ameri- can Board of Periodontology and fellow of the Royal Col- lege of Dentists of Canada. He currently maintains a private practice and actively lectures about innovations in periodontics and implant surgery. implants 1_ 2017 I 13