I also received two laser hair removal treatments on my beard and have come to regret them. I realize now that the treatments were unncessary and would like them reversed. Unfortunately, after a year and a half, my facial hair continues to grow in splotches and streaks. Should I wait to see if my beard will eventually grow back? Is there any procedure that will reverse the effects of the laser? Or do I have no choice but to bite the bullet and get my streaks removed?
People gray at different rates in different places--some gray on the scalp before the beard, others the reverse. It is therefore impossible to answer your question about melanocyte development in a systematic way.
For better or worse, laser hair removal is not always permanent--hair often grows back, and most of the time the hair comes in the same color as before, if not necessarily the same thickness. I have not seen hair come in white as a result of laser hair removal. I suspect that the hair looks lighter because it's thinner. In time it is likely to look even with your other hair.
While I understand your concern, in 8 years of laser hair removal experience, I have seen people who are dissatisfied because their hair didn't go away completely or because it came back, but never anyone who fwlt it was the worst mistake of their life. I think if you wait, you'll be OK.
Best.
Dr. Rockoff