Evaluating the effectiveness of low-level laser therapy in reducing local anesthesia injection pain in children

Abstract

Aim The aim of this study was to evaluate the efficacy of low-level laser therapy (LLLT) in reducing the pain of needle injection during local anesthesia in children. Materials and Methods Twenty cooperative healthy kids participated in this research; their ages were between 8-12 years old. In laser group (LG) LLLT diode laser (635 nm; continuous mode; 100 mW; 48.0 J/cm²) was applied buccally in one side of the mandibula or maxilla in contact with the soft tissue for 120 second. While in the contralateral side 20% Benzocaine Gel topical anesthetic was applied for the same time and this was the control group (CG). Then a short needle was inserted in each side and the pain was evaluated for each side separately using the Wong-Baker Faces Pain Rating Scale (PRS). Non-parametric analysis was applied and data were analyzed for statistical significance (p < 0.05). Results The total cases were twenty, (10 in the maxilla and 10 in the mandible). The "no pain" and "severe pain" rates in the PRS were 41.7% and 3.3% for the LG and 21.7% and 11.7% for the CG, respectively, during injection. The mean pain degree was 2.6 in CG while it was 1.2 in LG. Wilcoxon analysis revealed a statistically significant difference between LG and CG (P=0.001<0.05). While there was no significant difference in evaluating pain degree according to the order of technique, gender, place of injection, previous dental experiment, and behavior assessment in both methods. Conclusion Administration of LLLT diode laser (635 nm) can be considered for decreasing pain of injection in children and it is more effective than 20% Benzocaine topical anesthetic gel, regardless the order of technique, gender, place of injection, previous dental experiment, and behavior assessment.