Tom,

Welcome to NeuroTalk. Glad to hear you survived your crash with only minor issues. Hope your hand surgeon is one of the good ones. I have not been so lucky with hand surgeons.

I think you should consider a few things. A dentist chair is rough on the neck. Lots of tensing of neck muscles and such. The HANS system helped but did not prevent all cervical trauma. C-1 to occiput and C-1 to C-2 can be very sensitive to inflammation. This can make symptoms come roaring back due to poor cerebral blood flow and such.

Did the dentist give you any nitrous oxide to help you relax ?

I suggest you avoid sleeping with your head turned. If you sleep on your side, be sure your pillow supports your head so your neck is straight.

You may benefit from an assessment and maybe an Epley maneuver by a good vestibular or physical therapist. The crystal material in your ear may need to be re-positioned. It is a simple assessment and simple treatment.

My best to you.