Objectives
This study aimed to assess the frequency of temporomandibular disorders (TMDs) and their correlation with improper operating posture in Iranian dentists.
Materials and Methods
This cross-sectional study was conducted on 59 dentists practicing in Yazd city, Iran with improper operating posture according to the rapid upper limb assessment (RULA) tool (level 2 or higher). Neck pain and disability were evaluated by the neck disability index (NDI), and neck flexion and rotation were assessed by the flexion rotation test-active (FRT-A). The frequency of TMDs was evaluated by clinical examination and Fonseca’s questionnaire. Data were analyzed by the Fisher’s exact test and Spearman’s correlation test (alpha = 0.05).
Results
A significant correlation was noted between improper posture and TMDs in 23-28-and 29–34-year-old age groups, males and females, in dentists with less than 4 years of work experience, in general dentists, in participants working for a maximum of 38 hours/week and a minimum of 39 hours/week, those visiting a maximum of 3 patients or a minimum of 4 patients per shift, those not using a dental loupe, and those with a suitable dental unit according to their dominant hand (P < 0.05). A significant correlation was found between the RULA level and severity of TMDs in dentists (r = 0.476, P < 0.001). The NDI score had a significant direct correlation with the TMD score (r = 0.476, P < 0.001) while a significant inverse correlation was found between the FRT-A and TMD scores (r=-0.414, P = 0.023).
Conclusion
The frequency of TMDs and neck disability was higher in dentists with improper operating posture.