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Bernard J. Hennessy

, DDS, Texas A&M University, College of Dentistry

Last full review/revision May 2020| Content last modified May 2020

Bruxism is clenching or grinding of teeth.

Bruxism can abrade and eventually wear down enamel and dentin in the crowns of teeth, damage metal or ceramic dental crowns, and cause teeth to become mobile. Bruxism is considered a multifactorial condition. Tooth abrasion and erosion is often worse in patients who also have gastroesophageal reflux disease (GERD) and/or obstructive sleep apnea; the understanding of the association between sleep apnea and bruxism is evolving.

Bruxism can occur during sleep and while awake. In some people, bruxism causes headaches, neck pain, and/or jaw pain. The most severe and extensive grinding and clenching occurs during sleep, so the person may be oblivious to it, but family members might notice.

Treatment requires that the patient consciously try to reduce bruxism while awake. Plastic oral appliances (night guards) that prevent occlusal contact by fitting between the teeth can be used while sleeping. When symptoms are severe, a guard can also be used during the day. Usually, such devices are custom-made and fitted by dentists. However, if the only problem is tooth wear, over-the-counter (OTC) heat-moldable devices fitted at home are available, but a dental evaluation should first be done to assess the severity of wear and determine whether an OTC device is adequate. Mild anxiolytics, particularly benzodiazepines, may help until a night guard is available but should not be used for extended periods.

(See also Evaluation of the Dental Patient.)

More Information

  • Manfredini D, Colonna A, Bracci A, et al: Bruxism: A summary of current knowledge on etiology, assessment, and management. Oral Surgery 2019. doi: 10.1111/ors.12454.

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