De FelĂcio CM, et al.: Electromyographic indices, orofacial myofunctional status and temporomandibular disorders severity: A correlation study. J Electromyogr Kinesiol. 2012.
Abstract
This
study examined whether there is an association between surface electromyography
(EMG) of masticatory muscles, orofacial myofunction status and
temporomandibular disorder (TMD) severity scores. Forty-two women with TMD
(mean 30 years, SD 8) and 18 healthy women (mean 26 years, SD 6) were examined.
According to the Research Diagnostic Criteria for TMD (RDC/TMD), all patients
had myogenous disorders plus disk displacements with reduction. Surface EMG of
masseter and temporal muscles was performed during maximum teeth clenching
either on cotton rolls or in intercuspal position. Standardized EMG indices
were obtained. Validated protocols were used to determine the perception
severity of TMD and to assess orofacial myofunctional status. TMD patients
showed more asymmetry between right and left muscle pairs, and more unbalanced
contractile activities of contralateral masseter and temporal muscles (p
lesser than 0.05, t-test), worse orofacial myofunction status and higher TMD
severity scores (p lesser than 0.05, Mann-Whitney test) than healthy subjects. Spearman coefficient revealed significant correlations
between EMG indices, orofacial myofunctional status and TMD severity (p lesser than 0.05).
In conclusion, these methods will provide useful information for TMD diagnosis
and future therapeutic planning.