Variables Associated with Jaw Clicking in a South Australian Population: A Cross-Sectional Study

Background: The influence of medical and dental factors on jaw clicking within the South Australian population remains unexplored, and there is a lack of research on the impact of occlusal therapy on dynamic jaw movement parameters in this population. Purpose: This study investigated the potential significant associations between specific aspects of patient histories, occlusal therapy, and self-reported or observed jaw clicking in a population from the state of South Australia. Methods: Seventy individuals aged 18 to 65 participated in a cross-sectional study. Data collection included comprehensive medical, social, and dental histories, followed by evaluations of jaw function. Twenty-six out of the seventy individuals reported jaw clicking. Electrognathography assessed maximum mouth opening, surface electromyography evaluated masticatory muscle function, and joint vibration analysis measured individual joint vibration amplitudes and integrals. Logistic regression models analysed overall variable effects, while sub-models focused on predictors related to occlusal therapy, specifically orthodontic intervention. Independent t-tests and Mann–Whitney U tests compared jaw functions between participants who received occlusal therapy and those who did not. Results: The number of third molars extracted, vitamin D deficiency, and self-reported mental health disorders (R2 = 0.414, p = 0.048) emerged as significant predictors for jaw clicking. Factors associated with occlusal therapy showed no significant association with jaw clicking (R2 = 0.59, p = 0.027). Furthermore, there were no significant differences observed in mouth opening (t-stat = −0.439, p = 0.662), muscle activity, and joint vibration analysis between participants who underwent occlusal therapy and those who did not. Conclusions: Within the selected study population and limited sample size, the number of third molars extracted, vitamin D deficiency, and self-reported mental health disorders were associated with jaw clicking.