We wanted to report three cases of bruxism who were intractable to conventional management such as dental protection or medication but responded to motor point blocks (MPB) with botulinum toxin-A (BTX-A) on mastication muscles. Untreated, bruxism causes unfavorable complications of masseter hypertrophy, headache, temporomandibular joint destruction, and furthermore total dental wear and malnutrition. Our three patients had no previous history of bruxism or any neuromuscular disorder. They were presented with decreased cognitive function and severe bruxism about 6 months after brain injury. We managed the patients with MPB of BTX-A on each masseter and temporalis muscles. Bruxisms were markedly improved about 2 weeks after MPB without any complications. On follow-up 6 months after MPB, two of three patients remained free of bruxism and another patient revealed attenuated bruxism with decreased severity and frequency. Therefore, we think that MPB with BTX-A could be considered as a treatment option for severe bruxism in brain-injured patients. (J Korean Acad Rehab Med 2003; 27: 442-445)
