How to sue a dentist?

When I was eight years old, I went to the dentist for the first time. Yes, I know everyone is scared of the dentist, as was I, but for some reason I was more scared of this dentist than I felt I should. For starters, parents weren't allowed back in the room with the children. When he started treatment, he did not tell me he was going to stick me with a needle in my mouth. As you can imagine, I freaked out. Then my cheeks and tongue started to go numb and no one told me why. What really got me was when he kept telling me to stop crying. As he began to drill, I can tell you I felt every single bit of that drill going into my teeth. All of it. My mother and grandmother told me that they could hear me screaming from in the waiting room. He told me that it wasn't hurting me and to stop crying. Years later I am in extreme pain and it is only on the teeth that he filled. Do I have a case?