My question involves collection proceedings in the State of: Maryland

I recently had a root canal. The dentist office told me the cost would be $1,000. I paid the bill at that time. The dentist drilled the root and put in a temporary filling and told me to come back in two weeks for him to check it out and put in a permanent filling. Three days later the tooth was killing me and I went back to the dentist.

He removed the temporary filling and said the tooth was still infected and filled with pus. He cleaned the hole and packed it with cotton to allow any additional pus to drain, and told me to come back at the time I had earlier scheduled for the permanent filling.

When I went back for the permanent filling he decided to enlarge the canal. Then, he put in the permanent filling.

Three days later I received a bill for an additional $190. I asked what the additional charge was for and was told it was for a filling the root canal opening and enlarging it. I questioned why I was being charged for a filling when I was told the root canal would be $1,000. I asked didn't my original payment didn't cover the cost of the root canal. I was told, normally yes, but the dentist decided additional work was needed and they were billing me for it. They said nothing about this additiona cost while I was at the office and when I left.

My position is that I was told a root canal would cost $1,000 and I paid for it. I assumed I was getting a complete job.

Can you tell me if I am obligated to pay this additional charge?

Thanks.