The effect of indirect vision skills on head and shoulder posture among Korean dental hygienists.

OBJECTIVES This study aimed to investigate the effects of indirect vision skills on head and shoulder posture in dental hygienists. MATERIALS AND METHODS This cross-sectional study included a total of 100 female clinical dental hygienists. It evaluated musculoskeletal symptoms of the neck, shoulders and back, head and shoulder posture (craniovertebral angle [CVA] and sagittal shoulder posture angle [SSPA]). Indirect vision skills were assessed using the O'Connor tweezer test under indirect vision with a mirror. To analyze factors associated with the CVA and SSPA, an independent t-test, one-way ANOVA, and multiple linear regression analysis were conducted, respectively. RESULTS The body region in which the greatest number of symptoms of work-related musculoskeletal disorders were recognized was the neck (89.0%). In the multiple linear regression model, which adjusted for other factors associated with musculoskeletal disorders, dental hygienists with poor indirect vision skills showed relatively small SSPA value (P < 0.05). However, indirect vision skills were not associated with the CVA value. CONCLUSIONS Good indirect vision skills contribute to the prevention of rounded shoulders in dental hygienists. Therefore, where possible, dental hygienists should perform clinical procedures using indirect vision with a dental mirror to maintain a balanced posture and reduce flexion of the back or the neck. A dental hygiene curriculum should include training to improve clinical skills, as well as education regarding dental ergonomics and a monitoring system to determine whether ergonomic principles are well observed.