In most cases, root canal treatment has a very high long-term success rate if properly performed and cared for. However, in some cases, root canals can fail months or years later if bacteria re-infect the tooth through cracks, breakdowns in restorations placed over the access hole, or other issues. With good oral hygiene habits, regular dental visits, and prompt treatment of any new decay or damage, the tooth can be protected and a root canal retreatment avoided.