In addition to the many published research studies over the years in the U.S. involving the TMJ Scale, studies in other countries and cultures have also been ongoing. Many have expressed an interest in reading about such studies. Therefore, this is one example of a study done in Ottawa, Canada.
Wexler GB, McKinney MW. Assessing Treatment Outcomes in Two TMD Diagnostic Categories Employing a Validated Psychometric Test. Jour of Craniomandib Practice, 13(4):256-263, 1995.
This study measures the effects of treatment interventions on two classes of temporomandibular disorder (TMD) patients in a dental practice in Ottawa, Canada. Other studies of TMD treatment outcome have employed subjective, largely qualitative and nonquantitative measures of symptom levels to make this type of assessment, rendering such research largely incapable of being replicated. The current study employs the TMJ Scale, a validated and psychometrically-developed symptom inventory, to measure symptom levels before and after treatment. The study first determined the sensitivity (92.1%) and specificity (88.1%) of the TMJ Scale for 219 patients in the practice population. One hundred and eleven consecutive TMD patients completed TMJ Scales prior to treatment, and then were retested after the completion of treatment. Results indicate that patients with symptoms of internal joint derangement reported more symptomatic improvement than those with predominantly muscular symptomology, despite the fact that the latter manifested lower symptom levels initially. Patients with internal derangement symptoms initially presented with lower levels of psychological symptoms than patients with muscular symptoms. Substantial improvements in both groups were noted, employing TMJ Scale percentile rank changes as outcome measures. This study can serve as a model for future research toward establishing baselines for expected TMD symptom improvement.