The course covers the pathophysiological principles of bruxism/CMD, clinical diagnostics (anamnesis, palpation, functional analysis), and the targeted injection of botulinum toxin into the masseter muscle . It covers point vs. fan technique, injection depth, quantity calculation, laterality compensation, and follow-up assessments. We discuss indications/contraindications , off-label use in dentistry, informed consent, documentation, and the management of side effects (e.g., masticatory muscle weakness, asymmetries). Practical exercises reinforce landmarks, needle/cannula selection, and sterile workflows. We also address combinations with splint therapy and physiotherapy measures. The course deliberately stays within the scope of dentistry and clearly defines cosmetic applications (forehead/glabella/crow’s feet/lips). This allows you to integrate masseter treatments into your dental practice in a legally compliant and quality-assured manner.