I just had one of my fillings replaced and was REALLY concerned about it. I informed the dentist of my tinnitus and dosed up on magnesium and NAC before the visit. The sound levels were actually very, very tolerable and lower than what I was expecting. She took a couple of breaks in between but she said it would be difficult to do something like 10 seconds on, 5 seconds off. In any event, no spike whatsoever after the drilling. It went so well I'm going to proceed soon with having some of my other teeth done because they need it.