Zygomatic implant placement using a robot-assisted flapless protocol: proof of concept.

Robotic assistance can help in physically guiding the drilling trajectory during zygomatic implant positioning. A new robot-assisted strategy for a flapless zygomatic implant placement protocol is reported here. In this protocol, a preoperative computed tomography scan is used to plan the surgical path. After surface registration, the ROSA robot (Zimmer Biomet Robotics) guides several steps, which are performed with shared control. The surgeon performs the drilling and tapping, guided by the robotic arm, which is positioned according to the planned trajectory. Placement of the zygomatic implant is done manually. Immediate intraoperative 3D verification is performed by cone beam computed tomography (flat-panel detector, Medtronic O-arm II). Four zygomatic implants were placed in the case patient according to the flapless protocol, with a mean vector error of 1.78 mm (range 0.52-4.70 mm). A screw-retained temporary prosthesis was placed on the same day. No significant complications were observed. The application of this robot-assisted surgical protocol, which guarantees a very high degree of precision, may reduce inaccuracies in the positioning of zygomatic implants that could deviate from the surgeon's plan. This appears to be a potentially safe flapless surgery technique. Drill slipping on the crest or on the maxillary wall is the main source of error in this procedure, emphasizing the usefulness of the assisted surgical guidance with haptic feedback.