Chin implant failure rate and removal, what is the correct placement?

Thank you for your question.
Depending on the material of the chin implant, the relationship with soft tissues and bone will be different.
Silicone implants produce a capsule which is typically smooth and can lead to gliding of the soft tissues down, so after removal of implants it is imperative to supported well and possibly to make some cuts through the capsule to help the soft tissues to stick together. In addition, silicone implants have a tendency to erode the bone under them.
Medpor implants (porous polyethylene implants) form a rough surface capsule and do not erode the bone. It is still wise to support that a soft tissues after implant removal, but even the chin strap for the first week can help fix in position the soft tissues of the chin.
Gore-Tex implants are somewhere in the middle. They form a smoother capsule but do not tend to erode the bone.

Thank you for your question. Chin implants often last a lifetime, so you may never have a reason to remove your implant. If you do, it is probable you will have some sagging in the area. Skin tissue does tend to lose elasticity over time, leading to laxity and looseness. At that time, you could opt to have another procedure to address the laxity if you choose. I advise you to find an experienced, board-certified facial plastic surgeon for further assessment and advice. 

if a small chin implant is placed and fixed properly and it has the desired aesthetic result it is going to last a lifetime and need no future adjustments. Like all implants placed anywhere on the body if it is removed decades later, when the surrounding tissues are older and less forgiving, it is fair to say that the tissues are not going to return to their preoperative tightened state when you were younger.. This should never be biologically expected. The question is whether there will be a soft tissue deformity but whether its magnitude will be aesthetically significant.   

Hi sophie363,A chin implant can be placed either sub periosteal or supra periosteal (under or on top of the periosteum) or even hybrid (partly under, partly above). In our experience, there is not much difference in terms of clinical result. If you do decide to remove a chin implant, sagging or deformity of the chin rare occurs, however, as you age, your body, skin, musculature will change hence after implant removal, you chin may no longer look the same as it once was, before the implant was placed, especially if it had been years.