We would like to focus on the various CBCT-generated implant guides that are available and look at their advantages and disadvantages. A CBCT-based implant guide is a state-of-the-art concept that represents the highest aspects of implant technological advancements.
This month’s section revisits guided implant surgical applications, a topic that will appear in each December issue. We will focus on the various CBCT-generated implant guides that are available and look at their advantages and disadvantages. A CBCT-based implant guide is a state-of-the-art concept that represents the highest aspects of implant technological advancements.
Of the 3 categories of guides available, tooth-supported guides for quadrant implant dentistry is the most predictable and simple of the guided implant scenarios. A tooth-supported guide has little room for error, as it is a hard-tissue-supported guide that is supported by teeth that are visible and accessible. This is different than a bone-supported guide, which is more complex surgically and more involved to create.
Soft-tissue-supported guides for full-arch implant dentistry are appropriate when the final full-arch implant-supported prosthesis does not required alveoloplasty. If alveoloplasty is required for prosthetic thickness or to hide the prosthetic smile interface, then a bone-supported guide is needed. A soft-tissue-supported guide can be used when extractions are being done concurrently at the time of surgery, but extractions can create complexities with a soft-tissue-supported guide. An example of extractions causing a complexity with a soft-tissue-supported guide is if extractions cause the ridge shape to change during the process, rendering an inaccurate fit of the preplanned guide on the ridge.
Bone-supported guides for full-arch implant placement are by far the most technically advanced guide in both the presurgical planning and during the procedure itself. Bone-supported guides in full-arch treatment require that aggressive flaps be done in order for the guide to fit. When extractions are being performed, in addition to alveoloplasty, the complexities are furthered. In the situation of extractions and alveoloplasty, these full-arch guides are either stackable guides or multiple guides. These advanced guides are, in general, associated with higher costs for the doctor and require more time to plan and have delivered to an office.
Another scenario that has become more popular as technology has improved, are the dynamic navigation systems based on motion tracking technology. There are a few systems available now for this that are FDA approved. The concept is to take a prosthetically driven plan from a CBCT scan, and then place the implants in the correct position freehand with the assistance of an on-screen program guiding with precise feedback. While there is a learning curve with this technique, the concept certainly offers some exciting potential.
Implants Today advisory board member Dr. Randolph Resnik offers an excellent article that exemplifies many of the points I presented here. Randy’s dual-scan technique shows an accurate way to represent the prosthetic end result on a CBCT scan. As time goes on, guided-implant surgery and its related technologies will become even more innovative.
Also featured this month, Dr. L. Stephen Buchanan addresses today’s need for general practitioners to learn how to start placing and restoring dental implants in their own office.
Also by Dr. Michael Tischler