Great Expressions Dental Centers review: fees

Great Expressions in Ann Arbor overcharged me for a crown. Before any work was done, I was given an estimate of what the services would cost. At the time, I thought the estimate was high, but I didn't question it. I had to pay the full amount in advance before they would make the crown...which is understandable. I paid what they asked for in advance of the work. The work was done to my satisfaction (the Dentist there is very good), but a few weeks afterwards, I was sent a bill for an additional $260! They kept calling me for the money which I don't owe them. When I tried to work it out with them, (there must be a mistake) they just kept telling me I had only signed an estimate for services...and it ended up costing more. This is B.S. and this is how they rip you off. I have dental insurance, and they were paid from my insurance, and from my own pocket...but because they had me sign an "Estimate" they think they can now charge me anything they want after services have been rendered. Not gonna happen. Stay away from these people. Its too bad, because the Dentist is actually very good. I wish their Franchise business practices were more ethical.