All premolar and molar teeth require a crown with your general dentist within one month of root canal completion (unless a healthy crown is already on the tooth). Incisor and canine teeth will require a permanent restoration, which may be a crown. Failure to complete this work puts your tooth at high risk for either bacterial reinfection (via saliva) or fracture. Always check with your general dentist whether further procedures are required after completion of your root canal.