This prospective pilot study aimed to evaluate short-term clinical and ultrasonographic changes in the masseter muscle following botulinum toxin injection in patients with bruxism. Clinical assessments included pain evaluation using the Visual Analog Scale (VAS), while ultrasonographic evaluation included measurement of masseter muscle thickness and quantitative texture analysis using fractal dimension and histogram parameters. Measurements were performed at baseline, 14 days, and 90 days after treatment. The study aimed to assess both macroscopic and microstructural changes in the muscle tissue.