Grafting 2 years post implant restoration: any recommendations?

Hello, Doctors. This is not my best case. Of course I wouldn’t be seeking advice if it were, I suppose! I placed these Bicon implants two years ago and right from the outset, they weren’t ideally positioned, I know. Bicon’s design mandates a “counter sink” of the implants. That is, the implant shoulder should be buried subcrestally for predictable integration. Having placed around 100 Bicon implants, I have found this positioning to yield the best result. As you can see from the films, neither of these implants were counter sunk. Maybe they were doomed to fail from the very beginning. That said, they integrated enough so that they presented very solid 12 weeks later. Patient was asymptomatic and so I proceeded to restore the case.

The fit of the abutments into the implant well was good and the esthetic result was excellent. A year later when recall films were taken, I had not yet started mandating the automatic taking of PAs of implants in patients, placed by myself or otherwise. AS a result, I did not see the bone quality around these two on the bitewings taken at the time. Just the crestal bone height. However, last December, 2012, I had started to mandate these PAs and it was then that I first noticed some loss of bone density around these implants. I decided to wait for another 6 month recall to take another round of PAs to determine what was going on. Well, as the films show, bone loss is indeed occurring at a slow but steady rate. I believe that if left alone, one or both of these will end up either symptomatic or at least mobile which will then necessitate doing something.

Obviously, I would like to not remove these for any and all of the reasons one may think of. That said, I would like to attempt to solidify this region, possibly with a grafting procedure. I have done grafting with mixed results, both at the time of placement (especially if immediately placed after an extraction) as well as where there was to be a delayed placement. Truthfully, I would like to become better at it and have it be more predictable in my hands.

My question to you is, has anyone had success grafting an area around an implant(s) after the implant(s) has integrated and been restored? And if so, what have you found to work best? On the positive side, clinically the soft tissue margins are up at the crown heights and the implants are very solid, exhibiting zero mobility. On the negative side with respect to the gingiva, the tissue is thin and there is substantial pocketing as can be seen. Clinical pictures and radiographs are included so that you may hopefully get an idea of the situation. I’m not sure what order they will come up in. However, regarding the two radiographs, the one with less density of bone is unfortunately the one taken in June! Thank you for your time and consideration.

(click images to enlarge)

(December 2012)

(June 2013)