Objective To compare the effects of botulinum toxin type A (BTX-A) injections, occlusal stabilization splint therapy, and nocturnal overdenture removal on masticatory muscle activity and overdenture retention in patients with sleep bruxism wearing implant-retained mandibular overdentures.
Methods This randomized, single-blind, parallel-group clinical trial allocated patients with definite sleep bruxism to one of three groups (1:1:1): BTX-A injections with nocturnal overdenture wear, occlusal stabilization splint therapy with nocturnal overdenture wear, or nocturnal overdenture removal (control). Electromyographic (EMG) activity of the masseter and temporalis muscles was assessed at baseline and at 3, 6, 9, and 12 months. Overdenture retention was measured at 1, 3, 6, and 12 months using a digital force gauge. Intergroup comparisons were performed using one-way ANOVA with Tukey's post hoc test, and intragroup comparisons using repeated-measures ANOVA (α = 0.05).