Evaluation of an anamnestic questionnaire as an instrument for investigating potential relationships between orthodontic therapy and temporomandibular disorders.

A group of 100 patients who received orthodontic treatment, between the ages of 16 to 31 years, were asked to complete the TMJ Scale (an anamnestic temporomandibular disorder [TMD] questionnaire) and undertake a simple clinical TMD examination, the Helkimo clinical dysfunction index. The purpose of this study was to compare the TMJ Scale and the Helkimo clinical dysfunction index to validate the use of the TMJ Scale as a potential method with which to examine whether there is any relationship between TMD and orthodontic therapy. Comparisons between TMJ Scale scores from the orthodontically treated group were made with previously reported TMJ Scale data. In addition, comparisons were made between various treatment and malocclusion groups identified within the orthodontically treated sample. On the basis of the TMJ Scale global scale scores for the orthodontically treated group and two normative nontemporomandibular disorder groups described by Levitt, Lundeen, and McKinney, no differences were observed. Similarly, TMJ Scale comparisons between various treatment and malocclusion subgroups showed no statistically significant differences. The results of this study support the use of the TMJ Scale as a valid instrument with which to determine whether there is any relationship between orthodontic therapy and TMD.