[Purpose] Temporomandibular disorder is one of the many different adverse health
conditions that can be triggered by stress. Therefore, a biopsychosocial model has been
proposed to characterize the multifactorial nature of temporomandibular disorder. The aim
of the present study was investigate the correlation of salivary cortisol levels with the
activities of the masseter and anterior temporal muscles of patients with different
degrees of temporomandibular disorder. [Subjects and Methods] Forty-nine women between 18
and 40 years of age with a diagnosis of myogenous temporomandibular disorder based on the
Research Diagnostic Criteria for temporomandibular disorders were evaluated using the
Fonseca Index to determine the degree of the disorder. Salivary cortisol levels were
determined and surface electromyography was used to evaluate electrical activity in the
masticatory muscles. [Results] Positive correlations were found among the degree of
temporomandibular disorder, electromyographic activity and salivary cortisol: as women
with more severe temporomandibular disorder had greater electrical activity in the muscles
analyzed, especially the anterior temporal muscle, and higher levels of cortisol.
[Conclusion] Muscle activity was greater among individuals with severe temporomandibular
disorder and positive correlations were found among electromyographic activity, salivary
cortisol and the degree of temporomandibular disorder severity.