I had a root canal done by Dr. Carrara in 2007, and even though they took post-op x-rays, they never told me there was a problem during the procedure. I only discovered a year later, after the tooth got infected, that Dr. Carrara perforated the root while doing the root canal! It also turned out that she did not use a microscope for the root canal, even though it is a standard now and ensures better chance of success. Since so much time have passed, there is a significant bone loss and not a good chance of saving the tooth. The diagnosis "root perforation" was confirmed by two other endodontists, but when I asked Dr. Carrara to refund my money for root canal she was very rude and told me that she "sees no reason to refund my money".
The office stuff is also unpleasant and unhelpful. When I called them saying that I'm in pain because of the infected tooth, the only appointment they suggested was more than 2 weeks later! Even thought the receptionist told me Dr. Carrara would call me back, she never did.