The masticatory organ and stress management

  • S. SatoEmail author
  • R. Slavicek


In humans, the strong grinding and clenching function of the masticatory muscles known as bruxism has been thought to play an important role in mitigating stress-induced psychosomatic disorders by down-regulating the limbic system, the autonomic nervous system, and the hypothalamic-pituitary-adrenal axis. Experimental research results showed that bruxism-like activity has beneficial effects on stress-induced reactions such as increasing expression of Fos protein, neuronal nitric oxide synthase, phosphorylated extracellular signal-regulated kinase 1/2, corticotropin-releasing factor, and free radicals in the paraventricular nucleus of hypothalamus, alterations in the blood neutrophil/lymphocyte ratio and adrenocorticotropic hormone level, and stomach ulcer formation in animal studies, as well as increasing amygdala neuronal activity and salivary chromogranin A level in human studies. All of these findings strongly suggest that bruxism-like activity of the masticatory organ has the ability to decrease stress-induced allostatic overload. The health of the masticatory organ depends critically on occlusion, which must be of sufficient quality to successfully carry out its important role in managing stress. Occlusion and the brain must function in harmony. For these reasons, we must integrate the study of occlusion into the broader scope of medical science; in so doing, we will meaningfully advance the state of the art of dental care and general health care.


Bruxism Stress Masticatory organ Brain Allostasis 


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© Springer 2008

Authors and Affiliations

  1. 1.Department of Craniofacial Growth and Development Dentistry, Division of OrthodonticsKanagawa Dental CollegeYokosukaJapan
  2. 2.Danube University KremsKremsAustria

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