Does Maintaining Apical Patency during Instrumentation Increase Postoperative Pain or Flare-up Rate after Nonsurgical Root Canal Treatment? A Systematic Review of Randomized Controlled Trials

In light of the current evidence, maintaining AP does not increase postoperative pain in teeth with vital/nonvital pulp when compared with nonapical patency (low to moderate quality evidence). Furthermore, maintaining AP did not cause flare-ups (low evidence) and did not increase analgesic use (moderate evidence).