Effect of Orthodontic Treatment With Straight-Wire Appliance on the Incidence of Temporomandibular Disorders—A 3-Year Cohort Study

Abstract

Introduction: A change in occlusion during orthodontic treatment can affect muscles and joints surrounding the jaw, resulting in temporomandibular disorders (TMD). The aim of this study was to determine the effect of orthodontic treatment with straight-wire appliance on the incidence of TMD in young adults. Materials and Methods: A cohort study was carried out involving 177 adult patients (91 in the treatment group and 86 in the control group). Fonseca’s questionnaire was used for TMD evaluation for all patients at the time of obtaining orthodontic pretreatment records (T0). TMD assessment was repeated after an average of 3 years of initial assessment for both the treatment and control groups (T1). Results: The number of patients with TMD changed significantly ( P < .001) from T0 to T1 in both groups. The prevalence of TMD increased from 36.3% to 41.8% in the treatment group and decreased from 46.5% to 38.4% in the control group after 3 years. The relative risk of developing TMD after orthodontic treatment was 1.16, whereas the odds of TMD resolution after orthodontic treatment was 0.73, both of which were statistically nonsignificant ( P > .05). Conclusion: Orthodontic treatment with noncustomized straight-wire appliance has nonsignificant effects on the incidence of TMD in young adults.