If I was charged for a crown and it didn't get put in. Can I get a refund?

Dentist had put a temp on # 6 and did try one crown that they didnt like the way it seated, so they took another cast and sent it off. Then 9-11 months passed, life got too busy and i just didnt get in to try on the next crown. They turned me into a collection firm, in which over doubled my total billing. I paid it all off and called the dentist office to ask for all my x-rays and they said ok and they would look for crown, but only sent x rays (no crown). Paid 825.00 for crown. pls advise