I am one of the posters who has written about bad experiences and unfortunate but unusual side effects. I truly do not want to frighten anyone off from dental work.
I had a series of bad experiences in a very short time period where it seemed like the worst possible outcomes kept happening. Before these experiences, I was mostly afraid of talking with the dentist (a fear that extends to all medical professionals, nurses, aides, the receptionists, probably also the janitor in any medical building), with a moderate to mild anxiety about actual procedures. Now I have less anxiety about actual procedures and am more capable of communicating with the dentist, although I have new fears regarding some of my peculiar and particular reactions to dental work (one dentist called me the dreaded "interesting case").
After a few bad appointments with a new dentist, I was left with a mouthful of problems where I had had none before. I could have walked away and sworn off dentistry, and would probably still be subsisting on soup and pudding today, but instead I did some thorough research and chose a different dentist in my area. We spent a year fixing all the problems, with some further setbacks along the way, but I stuck with it and now have a very good relationship with a dentist that I trust, plus I am pain-free. As a bonus, I now know the tooth numbering system and know to always ask for my friend the bite block
Although I won't pretend that the bad experiences were a good thing, I am now much more confident in my capability to handle dental work, extending somewhat to medical procedures in general. I am also more empowered to ask questions even if I think it will annoy the dentist (or doctor), and I feel that I have a much stronger sense of what is important to me when receiving medical care. I know what qualities I want my dentist to have, and I do not feel bad about shopping around to find someone with whom I can have a good relationship. I expect to have better future encounters with the entire medical community as a result of my experiences.
Before my bad experiences, I would have have been very upset about having a root canal - now I know to expect an easy and painless procedure. I will need implants to correct a congenital problem - before it would have been unthinkable to have this done unsedated, but now I am confident that I will be able to select an oral surgeon who I can trust and anticipate an easy procedure without sedation.
So, that was pretty long, but I just wanted to say that even though dental treatment doesn't always go perfectly, it is better than the alternative. Think of it like taking a life-saving drug - that drug probably has a long list of possible side-effects, some terrible (like the super fast list read by the voiceover in a tv drug ad), but it is still worth taking the drug despite the (usually very small) risk.