Effect of Nd-YAG Laser Versus Epidermal Growth Factor Injection on Salivary Pain Mediators in Myogenic Temporomandibular Disorders (A Randomized Clinical Trial).

Abstract

Background: Myogenic temporomandibular disorder (MTMD) is a complex disorder of the masticatory apparatus. Many nonsurgical treatments have been introduced for treating MTMD chronic pain. The aim of this study is to test the effect of Nd-YAG laser versus epidermal growth factor (EGF) on painful chronic MTMD through monitoring pain scores and salivary pain mediators' levels.

Materials and methods: Twenty-seven patients with chronic painful MTMD, refractory to conventional treatments, were included in this study. Group I (n = 13) was treated using Nd-YAG Laser. Group II (n = 14) was treated by intramuscular EGF injections. Pain score using the numerical rating scale (NRS, 0-10), salivary nerve growth factor (NGF, mg/dL), and salivary glutamate (Glu, mg/dL) were measured at baseline (day 0), 1, and 3 months.

Results: NRS decreased significantly in both groups at 1 and 3 months compared to baseline. However, group II patients only showed a significant increase in NRS at 3 months compared to 1 month. In response to both treatments, NGF levels decreased significantly at 1 month compared to baseline. However, NGF levels at 3 months were significantly higher than baseline in both test groups. Glu levels showed a significant decrease in group II patients only at 1 and 3 months compared to baseline.

Conclusion: The results of this clinical trial have shown, for the first time, that Nd-YAG laser and EGF intramuscular injection can offer effective non- to minimally invasive treatment options for pain alleviation in chronic MTMD. Salivary NGF is a promising noninvasive sensitive biomarker for chronic painful MTMD. EGF intramuscular injection had a direct effect on salivary Glu levels.

Trial registration: This clinical trial was registered at ClinicalTrials.gov. Identifier: NCT06044974.