Effect of MTAD on Postoperative Discomfort: A Randomized Clinical Trial

J Endod. 2005 Mar;31(3):171-6. doi: 10.1097/01.don.0000137642.50944.a2.


The purpose of this study was to compare levels of postoperative discomfort after cleaning and shaping of root canals using two protocols for removal of smear layer. Seventy-three consecutive patients requiring root canal treatment were included. At random, canals were cleaned and shaped with one of the following protocols. In group 1, 5.25% sodium hypochlorite was used as the root canal irrigant. The smear layer was removed by placing 17% EDTA in the canal(s) for 1 min followed by a 5-ml rinse with 5.25% NaOCl. In group 2, canals were irrigated with 1.3% NaOCl; the smear layer was removed by placing MTAD in the canal(s) for 5 min. Access cavities were closed with a sterile cotton pellet and Cavit. The patients recorded degree of discomfort at various time intervals after cleaning and shaping on a visual analogue scale for 1 wk. No significant statistical difference was found in the degree of discomfort between the two groups (p = 0.58).

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Analysis of Variance
  • Chelating Agents
  • Chi-Square Distribution
  • Edetic Acid
  • Humans
  • Pain, Postoperative / etiology*
  • Polysorbates / adverse effects*
  • Root Canal Irrigants* / adverse effects
  • Root Canal Preparation / adverse effects
  • Root Canal Preparation / methods*
  • Smear Layer
  • Sodium Hypochlorite
  • Surface-Active Agents / adverse effects*
  • Surveys and Questionnaires
  • Toothache / etiology*


  • Chelating Agents
  • Polysorbates
  • Root Canal Irrigants
  • Surface-Active Agents
  • Edetic Acid
  • Sodium Hypochlorite