I didn't go to the dentist for 6 years because of my anxiety. (I know how gross!).
By then, I was diagnosed with moderate periodontal disease. Anyway had to have gum surgery at 3 seperate times. The only way I got thru it was the periodontist pre-treated me with 17 mgs. of valium each time. I still felt a bit apprehensive, but was able to do it! And I was so proud of myself. BTW, found out pretty much any dentist or clinic will pre-treat you with valium if you ask for it, even for basic cleanings.