While I was Dr. Mitchell's patient he performed a root canal treatment on a molar. A few years later, while still his patient, my upper jaw swelled and became sore. Dr. Mitchell gave me antibiotics and the problem subsided. Then, during the Christmas/New Year holidays the problem returned more severely. The office was closed for the week, so my son left a message describing the emergency and requesting an immediate call back when the office opened again. By this time my cheek was red and a little swollen. We waited for the entire day after the office reopened, but no call. So we called again the next day and were told that they were "too busy" to return our call.
We went to another dentist, who diagnosed an abcess and infection in the root canal of the tooth that Dr. Mitchell had treated. The new dentist made an emegency appointment with an endodontist the next day so that the infection could be cleaned out and the tooth sealed. I was 93 at that time.