Bruxism

Tooth clenching may not cause obvious tooth wear. In addition, tooth wear is not a direct measure of current bruxism activity but rather of the accumulated effects.[54]Koyano K, Tsukiyama Y, Ichiki R, et al. Assessment of bruxism in the clinic. J Oral Rehabil. 2008 Jul;35(7):495-508. http://www.ncbi.nlm.nih.gov/pubmed/18557916?tool=bestpractice.com If severe, tooth wear may necessitate dental rehabilitation (fillings, crown, bridges).[126]Johansson A, Johansson AK, Omar R, et al. Rehabilitation of the worn dentition. J Oral Rehabil. 2008 Jul;35(7):548-66. http://www.ncbi.nlm.nih.gov/pubmed/18557919?tool=bestpractice.com

Repeated activation of jaw muscles can lead to a functional hypertrophy, most noticeably as a training effect on the masseter muscles.[54]Koyano K, Tsukiyama Y, Ichiki R, et al. Assessment of bruxism in the clinic. J Oral Rehabil. 2008 Jul;35(7):495-508. http://www.ncbi.nlm.nih.gov/pubmed/18557916?tool=bestpractice.com ​ This may be a cosmetic problem for some individuals. It is likely to be reversible if jaw muscles become less active.

The relationship between bruxism and jaw muscle pain is not linear.[6]Manfredini D, Lobbezoo F. Relationship between bruxism and temporomandibular disorders: a systematic review of literature from 1998 to 2008. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2010;109:e26-50. http://www.ncbi.nlm.nih.gov/pubmed/20451831?tool=bestpractice.com ​[59]Svensson P, Jadidi F, Arima T, et al. Relationships between craniofacial pain and bruxism. J Oral Rehabil. 2008 Jul;35(7):524-47. http://www.ncbi.nlm.nih.gov/pubmed/18557918?tool=bestpractice.com ​​ There is evidence that patients with high levels of sleep bruxism have fewer muscle problems than patients with low levels of sleep bruxism.[48]Rompré PH, Daigle-Landry D, Guitard F, et al. Identification of a sleep bruxism subgroup with a higher risk of pain. J Dent Res. 2007 Sep;86(9):837-42. http://www.ncbi.nlm.nih.gov/pubmed/17720851?tool=bestpractice.com ​[127]Arima T, Arendt-Nielsen L, Svensson P. Effect of jaw muscle pain and soreness evoked by capsaicin before sleep on orofacial motor activity during sleep. J Orofac Pain. 2001;15:245-256. http://www.ncbi.nlm.nih.gov/pubmed/11575195?tool=bestpractice.com ​​ Awake bruxism appears to be a significant risk factor for jaw muscle pain.[128]Chen CY, Palla S, Erni S, et al. Nonfunctional tooth contact in healthy controls and patients with myogenous facial pain. J Orofac Pain. 2007;21:185-193. http://www.ncbi.nlm.nih.gov/pubmed/17717957?tool=bestpractice.com [129]Glaros AG, Williams K, Lausten L. The role of parafunctions, emotions and stress in predicting facial pain. J Am Dent Assoc. 2005;136:451-458. http://www.ncbi.nlm.nih.gov/pubmed/15884314?tool=bestpractice.com

Self reported bruxism and clinically diagnosed bruxism are positively associated with temporomandibular joint (TMJ) pain, although studies based on more quantitative methods to diagnose bruxism showed a lower association.[6]Manfredini D, Lobbezoo F. Relationship between bruxism and temporomandibular disorders: a systematic review of literature from 1998 to 2008. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2010;109:e26-50. http://www.ncbi.nlm.nih.gov/pubmed/20451831?tool=bestpractice.com Treatment of underlying bruxism should help relieve symptoms and prevent progression of TMD.

Temporomandibular disorders