Hi halliebeth,
It's pretty normal to have anxiety before any kind of surgery, so I'm sure if you let them know that you're feeling anxious, and that you have general issues with anxiety, they'll accomodate you as best as possible.
I've never had buspar before, so I'm not sure how it affects you... If necessary, you can talk to your Pdoc about getting a benzo like valium or xanax to take before the procedure.
I had my wisdom teeth pulled last december, and I understand how scary it can be. The best advice I have is just to be present with yourself and focus on your breathing. I meditate to help manage my anxiety and it works well for me. You don't necessarily have to achieve nirvana to calm yourself down though!

Slowing down your breathing helps a lot.
And by the way, my teeth were HORRIBLY impacted and I went to a dental school to have mine removed, and it was all okay in the end. Don't worry yourself too much, I'm sure you'll be fine! ^__^
Take care,
J