Hello
Fellow OCDer her too, not diagnosed but just ask my hubby and he will confirm it,LOL!
First off, just to let you know. I was a [removed] for 7 yr, so I have SOME history with dentistry,hehehe! This possible Rootcanal or filling you had done, the lazer you mentioned was it blue and did the dentist tell you that it was a lazer to do rootcanals? Reason why I ask, it has been 7 yrs since I practiced dentistry but still in that time I've not heard of a lazer to do a rootcanal. If it is a blue light, it very well could of been a curing light for white/ tooth colored fillings. These fillings are called Composits. Does any of this sound familar? Maybe your dentist saying these words? Well if it was a composite, nothing to be worried about, just a filling. Now if he did say it was a lazer for a rootcanal this is something that I'd love to hear about. It would be very interesting to me, something new in dentistry. I may even have to look it up.
Hope some of this info maybe helped, if you have any other question I'll TRY and answer them.
[Please do not mention that you were a medical professional for reasons outlined in the "Posting Policy". Thanks - Well-come Moderator.]