Do I Need Custom Jaw Angle Implants?

Q: I’m interested in customized mandibular angle implants for enhancement and to camoflage asymmetry and a contour defect from previous corrective jaw surgeries. I’ve had several jaw surgeries in the past. I had corrective jaw surgery which involved moving the lower jaw and chin forward. This surgery did not go very well. Due to an impacted wisdom tooth on the left side, I suffered a substantial amount of bone loss and was wired shut for several weeks. I also suffered nerve damage on the left side from the nerve be badly stretched. I had a revision surgery with another surgeon who repositioned the chin to correct asymmetry and placed a lateral onlay medpor jaw implant on the left side. I would like to have the implant removed and different style implants placed on both sides of my jaw. I would like to camoflage my defect and at the same time enhance the lower angle.

A: It appears you had orthognathic surgery and suffered what we call a ‘bad split’ on one of the mandibular osteotomy sides. (this is why it is a good idea to take out the wisdom teeth six months in advance of the procedure so the bone can heal and have better bone to work with. (I have been there before) I am assuming that the left side eventually healed but it resulted in the jaw being more posteriorly positioned on that side, resulting in chin asymmetry. Then you went on to have a chin osteotomy for anterior asymmetry correction and an onlay implant over the healed but deficient side of the lateral mandible where the sagittal split went bad.

I don’t necessarily think you need a custom implant on the left side. While it certainly can be done, the cost difference to do so may not be the effort. A careful analysis of your facial photos and x-rays is first needed to determine of that is necessary. Most of the time the problems can be improved with implants that are available off-the-shelf. You will likely need a different style and size of implant for the left side than the right. One option is the Medpor Ramus jaw angle implant with an inferior ridge on the left side. That type of implant would cover both the angle and the ramus and inferior border where the old bone defect site is. That would provide 7mms of angle width with the choice of either 5mm or 10mm lowering of the inferior ridge. The best way for me to make that determination is to look at a panorex film, which I suspect you have had at least one since your last surgery.

The other issue on the left side is the removal of the old onlay implant. That is usually not very easy with these Medpor implants but possible. You just don’t want to undergo a lot of ‘destruction’ trying to remove it unless it is really necessary. Sometimes it is better to leave it and implant over top of it. But that would depend on the size and location of the current implant in place. Again, a panorex film would be critical as the implant outline will usually show on that type of x-ray.

As for the opposite right side, I think either the smaller Medpor Ramus angle implant with the inferior ridge may suffice or a Medpor RZ angle with 7mms width. I would have a better feel for that based on an x-ray analysis.

What I would recommend is to get, or find if there are old ones, a panorex and a lateral cephalometric x-ray. With these I can trace out the mandibular shape and get a better 3-D for your unique anatomy. Then we can decide whether off-the-shelf or custom jaw angle implants are needed.

Dr. Barry Eppley
Indianapolis, Indiana