How come? By choice? Hope you don't mind me asking.
Yes, by choice.
As a kid I needed quite a few fillings and I always ended up with ulcers, bitten lips, cheeks and tongue. As I got into my teens a dentist suggested seeing how I went without and she said that if it was too much I could raise my hand and she would stop for a moment. That worked fine, with brief pauses in the drilling. Eventually I would clear my mind and meditate through the drilling and never needed any further anesthetic. Then I had good teeth for a long time.
As an adult I started needed some further treatment and couldn't find a dentist who would listen to me and work with me. One dentist sat and listened, and nodded, and agreed, and then asked me to lie back and open my mouth. She then immediately jabbed me with the injection!
I sat up and asked her if she even listened to me before assaulting me with unwanted drugs! She acted stupid and panicky and made all sorts of excuses.
Since then I haven't been able to relax as much even with a good dentist and have to have some anesthetic, though not much, even for relatively minor work.
Thought you had trouble sleeping?
I used to fall asleep when getting my tattoo's done.
Yes, I can sleep when I shouldn't, but put me in bed, at night and I am wide awake.