Progress of research on clincal application of computer-assisted implant placement techniques for zygomatic implant placement

There are two different types of computer-assisted implant placement techniques: static guide systems and dynamic navigation systems. There is greater accuracy and drastically reduced risk of perioperative/postoperative complications using the static guide compared to the freehand placement of implants. A zygoma drill guide can increase the precision of zygomatic implant placement. A combined bone- and mucosa-supported static guide can facilitate optimal zygomatic implant position. Using static guide systems for zygomatic implant placement faces several shortcomings. First, the use of static guides depends largely on the accurate positioning of surgical guides on the underlying tissue, and static guides do not have adequate underlying tissue to stabilize the surgical guides in a severely compromised defected maxilla. A second major concern with static guides is inadequate access for the drills, especially when using long twist drills with limitation in mouth opening. The dynamic navigation systems with actively tracked surgical drills have been proposed to provide real-time control of the drill position and achieve a precise zygomatic implant placement with minimal invasiveness, and challenges with static guides can be overcome. It is especially useful in patients with mouth opening limitation or extensive maxillary defect. The dynamic navigation technology has been recommended for placing more than one zygomatic implant on one side. Flapless placement of zygomatic implants guided by dynamic navigation has satisfactory safety and accuracy. Computer-assisted implant placement techniques can improve the accuracy and avoid complications of zygomatic implant placement for the reconstruction of severe maxillary atrophy and maxillary defects.