Evaluation of the single and combined therapeutic effects of individually manufactured earplug therapy in patients with myogenous temporomandibular disorders: A randomized controlled clinical trial

Objective To evaluate the effect of individually manufactured earplug therapy on pain intensity (PI), symptom severity (SS), and maximum mouth opening (MMO), in patients with myogenous temporomandibular disorders (TMD). Methods One-hundred-twenty patients were randomly allocated to six groups: Groups EP (earplug), OS (occlusal splint), EX (exercise), EPO (earplug with occlusal splint), EPE (earplug with exercise), and C (control). Outcomes were PI (assessed with a visual analog scale (VAS)), SS (assessed with the modified Symptom Severity Index Questionnaire (mSSI)), and MMO (evaluated with a digital caliper). Measurements were performed at T0 (before the therapy), T1 (1-month follow-up), and T2 (3-month follow-up). Data were analyzed using one-way analysis of variance (ANOVA), Tukey's HSD, and chi-square tests (alpha = 0.05). Results At T1 and T2, the greatest VAS and mSSI reduction was detected for the groups EPE (VAS = 5.3 +/- 1.05, 3.3 +/- 0.7; mSSI = 38.2 +/- 2.27, 43.6 +/- 3.94) and EPO (VAS = 5.2 +/- 0.91, 3.2 +/- 0.78; mSSI = 36.3 +/- 3.97, 42.2 +/- 3.19), respectively (p < 0.05). At T1, occlusal splint groups (groups OS (34.8 +/- 2.97 mm) and EPO (33.8 +/- 3.49 mm)) gave the highest MMO values, while T2 values did not constitute a significant difference with T1 (p > 0.05). Conclusions The short-term use of combined earplug therapy resulted in a decrease in both PI and SS. Improvement in MMO in participants using occlusal splints was observed in the 1st month and was maintained through the 3rd month. Clinical Relevance Earplug therapy can be applied as a complementary therapy to occlusal splint and exercise treatments to decrease PI and SS in patients with myogenous TMD. To achieve functional recovery such as MMO, its combined use with splints should be taken into consideration by clinicians.