My dentist just remembered to send me a bill from June 2006, am I still obligated to pay?

I don't have dental insurance and paid $335 last June for my wisdom tooth removal. Now a year later, I got a bill in the mail stating that I have a balance of $205 that's due. When I called the office, the staff told me my original payment was only to cover their estimate, and I still have to pay the remaining balance. Since they forgot to send me the bill for as long as 12 months, am I still obligated to pay?
--------------------
Yes and if you don't pay you risk the possibility of being sent to Collection. The procedures were done, insurance or no insurance, and some offices are WAY behind on their billing procedures. Hospitals are also notorious for this as well. You may not like it, but I will also bet money they had you sign an agreement stating such when you had your first visit. If there is a discrepancy in the bill you can talk it over with them, but an unexpected bill is rarely a friendly discussion. Good luck.
Source