I'm sorry Paige, I understand. I have 8 teeth that need work and I just can't make myself go, even the thought of medicines to relax me, gas, sedation....scares the mess out of me. *hugs*
You can find a dentist who works with phobia patients and will sedate you for non-surgical procedures. However, insurance generally won't pay for sedation of non-surgical procedures so you will have to come up with cash.
Due to very careful handling of my phobia, I have been able to reduce to just valium before non-surgical procedures, without any additional sedation. In the past, my phobia was so severe they had to put me under to clean my teeth.
You might start by finding a dentist who will give you a combination of valium and gas. That might be enough for you.
Please don't wait. It sounds like you are developing periodontal disease. I have 15 teeth left. You WILL start to lose your teeth if you do not get them cared for. Find a dentist who will work with you and get busy on those teeth and gums before it is too late.
It depends how bad its decayed, if it's salvagable, than they'll shave it down, probably root canal it if it's really bad and crown it.
Dentists do use the gas, but usually they don't use it for these types of procedures, it's usually for surgical types like when I had all 4 of my wisdom teeth pulled, i was put out.
Talk to your dentist and see what options there are!