Manual therapy versus home exercise in the treatment of bruxism: a randomized controlled trial with ultrasonographic, elastographic, and electromyographic assessment

Abstract

Bruxism is a prevalent condition associated with pain, functional limitations, and neuromuscular alterations. Although non-invasive physiotherapy approaches such as manual therapy (MT) and home exercise (HE) are widely used, randomized controlled trials integrating both clinical and objective assessments are limited. Therefore, this study aimed to compare the short-term effects of manual therapy and home exercise on pain, functional outcomes, and neuromuscular characteristics in individuals with probable bruxism using combined clinical and objective assessments. Thirty participants with probable bruxism were randomly allocated to MT ( n = 15) or HE ( n = 15) groups for an eight-week intervention. Clinical outcomes included pain intensity, Fonseca Anamnestic Index (FAI) scores, bruxism severity, trigger point count, and temporomandibular and cervical mobility. Objective assessments included ultrasonography (USG) for muscle thickness, shear-wave elastography (SWE) for muscle elasticity, and electromyography (EMG) for muscle activity. All assessments were performed before and after the intervention by a blinded assessor. Appropriate parametric and non-parametric statistical analyses were applied ( p < 0.05). Both MT and HE groups demonstrated significant improvements in pain intensity, FAI scores, bruxism severity, trigger point count, and mandibular and cervical mobility. USG findings showed reduced masseter and temporalis muscle thickness, while SWE revealed increased masseter elasticity in both groups with additional improvements in sternocleidomastoid (SCM) elasticity observed in the HE group. EMG results indicated decreased activity in the masseter, temporalis, and SCM muscles. Between-group comparisons showed no overall superiority; however, the HE group demonstrated greater improvements in cervical extension and rotation, temporalis muscle thickness, and SCM elasticity. Both manual therapy and home exercise are effective and safe physiotherapy interventions for individuals with bruxism, leading to significant improvements in pain, mobility, and neuromuscular function. The integration of clinical outcomes with ultrasonographic, elastographic, and electromyographic assessments provides comprehensive evidence supporting conservative rehabilitation strategies. Home exercise may be considered a practical conservative treatment option, although no overall superiority over manual therapy was demonstrated. ClinicalTrials.gov NCT07058311, 05/09/2025, retrospectively registered.