In addition to the many published papers over the years in North America (U.S. and Canada) using the TMJ Scale in research studies of temporomadibular disorders (aka 'TMJ'), there have been some interesting studies conducted in other countries and cultures. In response to requests to read about some of these studies, the following is one example of a study done in Brazil.
Nasr MK, Bataglion C, Nunes L de J, Bataglion SAN, Paiva AF, Application of the TMJ Scale and Electromyography in Masseter and Anterior Temporal Muscles in Subjects with Temporomandibular Joint Dysfunction With and Without Orthodontic Treatment and Operative Dentistry Restorative Treatment: Comparative Study, Jornal Brasileiro de Oclusao, ATM e Dor Orofacial, 2(5): 34-43, 2002.
This research had as its objective to verify in subjects at university all presenting temporomandibular joint dysfunctions and with operative restorative dentistry, divided in two groups, with and without orthodontic treatment, the electromyographic activity of the masseter and anterior temporal muscles in different mandibular positions, and the validity of the anamnestic questionnaire TMJ Scale. The results showed that, at the rest position and in maximum habitual intercuspation, the group of the subjects with orthodontic treatment showed less electromyographic activity in relation to the group that had not received orthodontic treatment, however the activities were shown more balanced. In the right and left movement, in both groups, there was a greater activity in the ipsilateral temporal muscles, in relation to the contralateral muscle. The TMJ Scale showed that this questionnaire appeared to be reliable and that it can be applied to the practice of dentistry, either in private or in epidemiologic studies.