I'm sorry you are going through this (and really traumatic as it happened to you). I don't understand how the dental work triggered the event, but I can empathize with your initial reaction as well as your beating yourself up now. I hope you can let that go - it may be that even if you had asked the dentist to stop, you would have had the same result.
I experienced Sudden Sensorineural Hearing Loss (SSHL) several years ago at about age 50. I woke up a little dizzy and feeling like my ear was a little plugged, but attributed it to allergies. The dizziness became unbearable that morning and long story short, I was referred from minor emergency center directly to an otorhinolaryngologist (ear+ doctor), evaluated & taking steroid & antiviral by that evening. I also had tympanic steroid injections. In the end, they don't know what caused it and I have severe/profound hearing loss in one ear. I now have a bone-anchored hearing aid (BAHA) which helps but isn't great in noisy environments, etc.
Since you are having problems with both ears, but also have some hearing in both(?) I suspect you will not have a BAHA - has your specialist talked to you about hearing aids or possibly cochlear implant? Also I understand there is treatment for disabling tinnitus - so ask your doctor about that. Aural (hearing) rehab is also a "thing," and that may be something that is beneficial for you.
Despite my outcome, anyone who experiences sudden hearing loss should seek immediate evaluation and treatment by a specialist. It is frightening, but from what I've read the chance of a repeat event is rare (~2%). My suggestion would be to share your anxiety and questions with your specialist, and try to figure out if your doctor has expertise in this area or if you want to seek a second opinion. Good luck.