I had crown placed on molar 18 in July of 2009. Within two weeks, the crown felt loose and within a month, I had an abscessed tooth. A call to the dentist netted me an appointment with a periodontist. A call to the periodontist netted me a talk with the receptionist who told me to push on the abscess to push the puss out to relieve pain. This may have worked if the puss had been obvious, but at the time, it was just really swollen. I did as directed and within a day, I had the beginnings of lock jaw. A visit to the periodontist wasn't very successful as I couldn't open my mouth, but he took x-rays and said the root didn't look infected. He noted the crown was loose and said he could do nothing until the infection had gone. The lock jaw continued for nearly five months. I've gone through several rounds of antibiotics and have to take pre-med antibiotics (for a pre-existing heart valve condition) before any procedure. I also now have a lima bean sized knot under my jaw and I have generally just felt off kilter since I had the crown put on. There's also a 'hole' now in my gum just below the tooth where the puss pocket burst. I just finished another 10 day round of antibiotics and am scheduled to have a root canal in an hour or so, but my infection is already back again. I called the periodontist and informed them the infection has returned and queried whether the procedure should be postponed and they told me to come in anyway. I've always had a suspicion that the tech, who didn't seem to know what she was doing when she was putting on the crown, might have left something under the crown. Now I'm wondering if I shouldn't just have the tooth removed. Molars #'s 5, 12, 21, 28 were all removed for my braces back in the 80's, so I only have three molars as it is. Suggestions? Or things I should ask the periodontist about before I let him work on this tooth? I appreciate any help. Thanks!