Permanent mimic musculature and nerve damage caused by sodium hypochlorite: a case report.

Sodium hypochlorite is often used as an irrigation solution during routine endodontic treatment. Before recementation of a post-retained crown on the upper left lateral incisor, the root canal was irrigated with sodium hypochlorite. There was no root filling in the root canal, and the apex was open after an earlier apicoectomy. Sudden pain with swelling of the left face side occurred during root canal rinsing. Three years later, a paraesthesia still remained in the affected region and a paralysis of some mimic muscles in this region was observed. There were no signs of improvement.