When and how did you find out/realize that he was a regular dentist and not and orthodontist? I only ask as your title and previous posts point to him being an ortho, and now that's changed.
jimnyc, I think powerxboy was correcting OUR use of the word dentist.
An orthodontist IS a dentist, however, just as an obstetrician is a doctor. Both an orthodontist and an obstetrician have chosen to specialize in their fields and, therefore, they have had more training and education to become qualified as specialists. But calling an orthodontist a dentist or an obstetrician a doctor is not wrong - it is just not giving them credit for their specialty.
Had powerxboy discovered the dentist who worked on his braces was NOT an orthodontist, THEN he could POTENTIALLY have a malpractice claim, depending on all facts. But I am not seeing a clear malpractice claim in what powerxboy has described here - especially if he did not inform his orthodontist of his genetic predisposition to tear trough (if dental work is even considered a tear trough risk, and I do not know enough about this to say that it is).
He should speak with an attorney in his area if he believes he has a supportable case and the attorney can give him a better idea if he has a case worth pursuing - this if a reasoned discussion with his current orthodontist does not resolve the problems he is experiencing.