Effect of Low-level Laser Therapy on Postoperative Pain after Root Canal Retreatment: A Preliminary Placebo-controlled, Triple-blind, Randomized Clinical Trial

J Endod. 2017 Nov;43(11):1765-1769. doi: 10.1016/j.joen.2017.06.028. Epub 2017 Sep 28.

Abstract

Introduction: Low-level laser therapy (LLLT) is a practical, nonpharmacologic technique for reducing pain. This study evaluated the effect of LLLT on postoperative pain after root canal retreatment (RCR).

Methods: This study enrolled patients (N = 36) who required root canal retreatment (RCR) on mandibular molar teeth, presented with periapical lesions with periapical index scores of 2 or 3, and had a pain visual analog scale (VAS) <50 and a percussion pain VAS <50. The participants were divided into 2 groups: (1) patients scheduled for RCR followed by LLLT (n = 18) and (2) patients scheduled for RCR followed by a mock LLLT (placebo) (n = 18). Postoperative pain was assessed using the VAS. Data were collected and statistically analyzed with the chi-square test, the independent sample t test, and the Mann-Whitney U test (P = .05).

Results: On the first 4 days, postoperative pain significantly reduced in the LLLT group compared with the placebo group (P < .05). However, no statistically significant differences in postoperative pain were found between the 2 groups after 5 and 7 days (P > .05). The number of patients who needed analgesics was lower in the LLLT group than in the placebo group (P < .05). No patient reported pain during LLLT application.

Conclusions: LLLT may reduce postoperative pain after RCR of mandibular molars.

Keywords: Diode laser; endodontic retreatment; laser; low-level laser therapy; postoperative pain; retreatment; root canal retreatment.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Double-Blind Method
  • Female
  • Humans
  • Low-Level Light Therapy / methods*
  • Male
  • Pain Measurement
  • Pain, Postoperative / prevention & control*
  • Reoperation / adverse effects*
  • Reoperation / methods
  • Root Canal Therapy / adverse effects*
  • Root Canal Therapy / methods