Electromyographic study of activity of the masseter and anterior temporalis muscles in patients with temporomandibular joint (TMJ) dysfuction: Comparison with the clinical dysfunction index

Reorganization of muscle activity in patients with chronic temporomandibular disorders

“…Even when induced experimentally in healthy subjects, pain produces decrease of activity in painful masseter muscle at 100% of MVC, but also in nonpainful jaw-closing muscles (Shimada et al, 2013). Ardizone et al (2010) also verified that patients with the greatest dysfunction exhibited a more pronounced activity decrease, although neither information about TMD diagnostic (if muscular, articular or both) nor symptoms duration were reported in their study.…”

“…Previous studies showed decreased raw EMG activity of jaw muscles in TMD patients compared to control subjects, association between decreased activity and increased severity (Ardizone et al, 2010), and asymmetry between affected side and non-affected side in unilateral TMD patients (Santana-Mora et al, 2009). To distinguish real changes from biological and instrumental noise, standardized EMG has been strongly recommended (Ferrario, Tartaglia, Maglione, Simion & Sforza, 2004;Ferrario, Tartaglia, Galletta, Grassi & Sforza, 2006), mainly for inter-individual comparison.…”

Association between headache and temporomandibular joint disorders in children and adolescents

“…The index is subdivided into five items, with three possible scores for each item (0, 1, and 5), depending on the clinical evaluation. The total allows classification into categories: absence of signs of TMJD (0 points), mild TMJD (1 to 4 points), moderate TMJD (5 to 9 points) and severe TMJD (10 to 25 points) (6)(7)(8)(9)(10). Clinical examinations were performed using Axis 1 of the Research Diagnostic Criteria for Temporomandibular Disorders (11).…”

Jaw-motor effects of experimental jaw-muscle pain and stress in patients with deep bite and matched control subjects

“…16 Although the specific study design does not allow for generalized conclusions related to the importance of deep bite to TMD pain, it does suggest that subsets of deep bite patients may be more at risk of developing a TMD problem under certain conditions. Many studies have also shown an association between electromyographic (EMG) muscle activity at rest and TMD severity, [17][18][19] but most studies and reviews do not support a close link between increased EMG activity and TMD pain and the vicious cycle concept continues to remain unsupported. Traditional studies have tested the effect of mental stress on EMG activity at rest and demonstrated subtle increases in EMG activity.…”