I can only hope that the same thing happens to him. One day maybe an unscrupulous dentist will tell him he needs four fillings (when he doesn't) and will do a crap job to boot. I know how that one feels, a Dorset dentist pulled that stunt on me in late 1991 before I did my radiography training. I had pain in both upper and lower pairs of molars and the {bleep}er said I had four gaping cavities that needed filling. He did that and the fillings plagued me (in the end I lost two of those teeth, the other two piss me off still). And do you know what the real reason was that I had that pain?
Wisdom teeth!!
Ja, I found this out when the pain didn't subside and I was back in JHB starting my course two months after the fillings. An X-ray proved it (the Dorset {bleep} also X-rayed me but 'missed' the real diagnosis). So I got myself four fillings all at once, for nothing, and I still had to have the wisdoms surgically removed.
Hopefully your mechanic and my previous dentist get marooned on a desert island together. People like that aren't even worth a paper bag full of piss.