The Stomatognathic System as an Expanding Frontier for Botulinum Toxin Therapy

Botulinum neurotoxin (BoNT) therapy has expanded from focal chemodenervation to a versatile therapeutic modality used across multiple medical specialties. The stomatognathic system is particularly suited to BoNT therapy because motor, sensory, articular, secretory, and aesthetic functions converge within a compact anatomical region. Current and emerging applications include oromandibular dystonia, dyskinesia, bruxism, tremor, hemimasticatory spasm, embouchure dystonia, masticatory muscle and temporomandibular disorder-related pain, trigeminal neuralgia, recurrent temporomandibular joint dislocation, sialorrhea, Frey syndrome, masseter prominence, gummy smile, and perioral wrinkles. Evidence and regulatory status vary substantially among indications, and many applications remain off-label. Dentistry and oral and maxillofacial surgery have historically played a limited role in BoNT therapy despite their detailed anatomical and functional expertise in this region. However, interest is increasing, and the recent approval of onabotulinumtoxinA in Japan for masseter prominence in adults younger than 65 years represents an important milestone. This review synthesizes current applications, limitations, safety considerations, and future directions, and proposes the stomatognathic system as a major expanding frontier for BoNT therapy.