Bruxism is grinding and clenching of the teeth with unconscious contractions of the temporal and masseter muscles while awake or during sleep. Bruxism occurs in 8%-16% of the population and is often an underdiagnosed condition that not only leads to dental problems but also to pain in the teeth, jaw, temporomandibular joint, and neck; headaches; and potentially, to tooth loss.
Although the pathogenesis of bruxism remains unclear, multiple factors, such as physical or psychological stress, malocclusion, sleep disorders and medication side effects, can cause bruxism. Treatment can be difficult given psychogenic and neurogenic components, and bruxism can be resistant to medical and behavioral therapy. There are various treatment options for bruxism, including oral splints; medications, such as muscle relaxants; antidepressants; and botulinum toxin. Multiple studies have shown that botulinum toxin injections into the masseter and temporalis muscles result in relaxation of the muscles and improvement of bruxism and the pain associated with chronic clenching and grinding.
In aby Al-Wayli, 50 subjects who reported nocturnal bruxism were randomized to receive botulinum toxin versus conventional treatment (pharmacotherapy or oral splints). After 3 weeks, 2 months, 6 months, and 1 year, patients who received botulinum toxin had significantly less pain after only one treatment than did the traditional treatment group. Similarly, in by Lee et al., subjects randomized to receive botulinum toxin versus a placebo saline injections showed not only decreased pain but also decreased bruxism seen with nocturnal electromyography.
In our clinic,Botulinum toxin when injected into the temporalis and masseter muscles also helps with tension headaches and migraines related to clenching of the jaw. Albeit effective, the dose of botulinum toxin used in the aforementioned studies ranged between 25 U and 40 U of botulinum toxin and were lower than what we have found to be effective. Our patients receive 50 U botulinum toxin in each masseter muscle (100 U total). In a small minority of our patients, the temporalis muscle also needed 15-20 U per side as well. Clinical improvement starts within 3-5 days, and patients can expect to have relaxation of the muscle and decreased pain for 6 months. Side effects include mild swelling and bruising. Rarely, if the injection is not performed properly, the risorius muscle may be paralyzed, leading to an asymmetric smile. In addition, if the botulinum toxin is underdosed, the pain may not completely subside and the patient may report some symptoms returning within a couple of weeks of the initial treatment. Most patients also report thinning of the face and jaw, which is a much anticipated and appreciated result. Masseter hypertrophy with and without bruxism is treated similarly with botulinum toxin to sculpt the lower face.
Bruxism is a growing problem leading to facial pain, headaches, migraines, and significant dental pathology. Traditional treatments have been ineffective at treating the pain and masseter hypertrophy associated with chronic grinding and clenching. Botulinum toxin is a safe, effective, treatment with little downtime or side effects for treating both the neurogenic and muscular components of bruxism.
Dr. Lily Talakoub and Dr. Naissan Wesley and are co-contributors to this column. Dr. Talakoub is in private practice in McLean, Va. This month’s column is by Dr. Talakoub. Dr. Wesley practices dermatology in Beverly Hills, Calif. Write to them at firstname.lastname@example.org. They had no relevant disclosures.
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