Botulinum toxin type A in the management of masseter muscle hypertrophy.

PURPOSE: We sought to evaluate the response of 6 patients with masseter muscle hypertrophy to botulinum toxin type A therapy.

PATIENTS AND METHODS: Six patients with unilateral or bilateral masseter muscle hypertrophy received intramuscular injection of the botulinum toxin type A. The functional and cosmetic results were evaluated as well as recurrence.

RESULTS: In all patients, satisfactory regression of the masseter muscle hypertrophy occurred and mild muscular pain was relieved. Recurrence was observed in 2 cases.

CONCLUSIONS: The use of botulinum toxin type A in masseter muscle hypertrophy therapy was shown to be a successful and safe treatment method. This procedure to control parafunctional activities involving the masticatory muscles of patients appears to be useful.