Assessment of ergonomic condition of Iranian dentists using RULA technique and its correlation with musculoskeletal disorders

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Pegah Rahbar
Parivash Shirkosh
Sahar Tehrani


Dentists; Musculoskeletal Diseases; Ergonomics


Objectives: The aim of the present study was to evaluate the ergonomic status of Iranian dentists using the Rapid Upper Limb Assessment (RULA) technique and its correlation with musculoskeletal disorders (MSDs).
Materials and Methods: This descriptive study was conducted on 152 dentists practicing in Ahwaz city, Iran. The ergonomic status of dentists was evaluted using the RULA method, and the prevalence of MSDs was assessed through the Nordic musculoskeletal questionnaire. Data were analyzed by the regression model, Chi-square test, and Mann-Whitney test (alpha=0.05).
Results: The highest levels of MSDs during the past 12 months were reported in the neck (71.1%) followed by the upper back (59.2%), wrist (55.3%), lower back (53.3%) and shoulders (52%). The RULA score was 3 or 4 in 38.8%, 5 or 6 in 57.2%, and 7 or higher in 3.9% of dentists. No significant correlation was noted between the RULA score and MSDs in the wrists, thighs, buttocks, shoulders, and ankles (P>0.05). However, dentists with neck (P<0.001) and arm (p=0.017) pain had significantly higher RULA score than those without pain in these areas.
Conclusion: The ergonomic status of Iranian dentists practicing in Ahwaz city was not satisfactory, and they had relatively high prevalence of MSDs, which calls for educational courses on this topic and measures to correct their posture.

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