If I value my health a fair bit more than most and am a transhumanist, when should I bother to get second opinions before having dental work done?

I had 16 fillings done a month ago and my teeth mostly all still hurt, so I'm going to go back to the dentist and see what he says as soon as I can, but I'm not sure what he'll want to do to me, if anything. (I think fillings are supposed to stop hurting after a week or two). I like him, and I want to trust him, and finding a new dentist would be annoying, but it's so weird and scary that I just had that many fillings done, because... I've always gone to the dentist every 6 months for a cleaning, and I never had to get a filling before, even though I always got routine x-rays to check for cavities every year. I'm only 22. I think that the reason I had to have that many fillings done was because I'd been downing tons of cough drops which contained sucrose for several months, for the reason that my acid reflux had been upsetting my throat.

I guess that I'm really just reminded of my frailty by this experience, and of how easy it is for someone to get old or sick, or even die. Sorry I'm such a bucking mess right now (mentally and physically), and thanks for any suggestions.