Effect of Root Canal Dressings on Extraradicular pH in a Sealed Apex Model: An In Vitro Study

Objectives

Endodontic treatment is mandatory after severe dental trauma such as avulsion or intrusion. Initial intracanal dressing with calcium hydroxide should be avoided according to international guidelines due to potential periodontal ligament damage by pH elevation. However, whether an intracanal dressing is able to alter the extraradicular site remains unclear. This in vitro study quantified extraradicular pH changes through dentinal diffusion of calcium hydroxide or Ledermix in a sealed-apex model in human teeth. Material and methods: Thirty-five cryopreserved human premolars were prepared with or without cemental defects and received UltraCal XS, Ledermix, or saliva as an intracanal dressing. In the test groups, apices were sealed with composite resin material; the positive control remained with open apices. Teeth were stored in NaCl solution. External pH of the solution was measured on days 1, 3, 5, 7, and 14. A mixed model was applied to determine the effect of group, apical plug, cemental defect, and time on pH alterations.