This is a garden variety middle-mesial canal i tretaed in 2009. The crown done by the referral was a bummer. Patient came back a year later with discomfort. The periapical lesion had healed, but the crown had an open margin leading to food impaction. I suggested changing the crown. Liviu Steier requested that I convert this case into a small article for Dental tribune U.K. Attached is the pdf from 2009.
Here is the Dental Tribune U.K article: