Patient-friendly definition from the DentistsDirectory.org dental glossary.
Bruxism is the involuntary grinding, clenching, or gnashing of teeth. Sleep bruxism — which occurs during sleep without the person's awareness — is the most clinically significant form, as it can generate bite forces three to ten times greater than those produced during normal eating. Awake bruxism, involving clenching during waking hours in response to stress or concentration, is also common but usually less damaging.
Many people with bruxism are unaware of it until a partner mentions the grinding sounds or a dentist notices the wear. Common signs include flattened, chipped, or shortened teeth; increased tooth sensitivity; jaw pain or soreness in the morning; headaches on waking; and visible indentations on the sides of the tongue from clenching. Over time, severe bruxism causes significant attrition (tooth wear), can crack teeth and fillings, and places sustained stress on the temporomandibular joint, potentially developing into TMD.
The primary treatment for sleep bruxism is a custom-fitted nightguard — a hard acrylic splint worn over the teeth during sleep that prevents tooth-to-tooth contact and distributes the force of grinding. A nightguard does not stop the grinding reflex but protects the teeth from its effects. Stress reduction techniques, botulinum toxin (Botox) injections into the masseter muscle, and certain medications can reduce grinding severity in some patients. Your dentist can assess the extent of wear and recommend an appropriate management plan.