Q: Dr. Eppley, does the mandibular angle implant bond to the bone through time? Or is it just the screws that hold it in place for the rest of my life?
A: There is no synthetic facial implant materials that truly bond to the bone in the truest sense of the word. Bonding denotes an actual bone ingrowth and attachment to the underlying bone without the interface of scar, much like a dental implant where bone bonds directly to the metal. That does not happen with either silicone or Medpor materials.
What does ultimately stabilize and maintain a facial implant into a secure position is the development of a surrounding layer of scar known as a capsule. This takes several months to form a solid capsule around the implant. So the primary purpose of implant screw fixation is to maintain the desired position until a good capsule forms. Medpor material does develop a more robust capsule formation than silicone but early implant stability can only be completely assured by screw fixation as that still takes time to develop. Medpor material also has a much higher frictional resistance (which is also why it is much harder to insert and usually needs bigger incisions) so this may help a little with early implant stability. But that is not enough for me to rely exclusively on this material property. Silicone has little frictional resistance and pocket development alone does not provide assurance that implant migration/mobility will not happen after surgery.
Dr. Barry Eppley