Musculoskeletal disorders of the neck and shoulder in dental hygienists and dental hygiene students.

PURPOSE: Dental hygienists have been found to have high rates of neck and shoulder disorders, but there is very limited information on risk factors associated with those disorders, the level of risk for students, and the relationship of prior work as dental assistants for dental hygiene students. This study examines self-reported and physician-diagnosed neck and shoulder pain. METHODS: A cohort consisting of 27 dental hygiene students with no prior dental occupation experience (mean age 24, 6.2 SD), and 39 dental hygiene students with prior experience as dental assistants (mean age 28, 6.0) and 94 experienced dental hygienists (mean age 46, 8.8) completed a questionnaire on risk factors and self reported pain, and were examined by a physician in reference to upper extremity findings and diagnoses. Analysis included tabular, trend, and logistic regression analysis. RESULTS: There were significant differences for risks, symptoms, and physician findings. Risk factors had a stepwise progression for students, student/assistants, and experienced dental hygienists, including working with a bent neck often or very often (79%, 89%, 96%, respectively, p<.001), static posture (39%, 50%, 63%, p<.001), precise motions (58%, 67%, 90%, p<.001), and repetition (79%, 86%, 98%, p<.001). Neck symptoms were reported by 37%, 43%, and 72%, respectively (p<.001), and 11%, 20%, and 35% for shoulder symptoms (p<.05). Similar patterns were demonstrated in physician findings, particularly for neck disorders (18%, 36%, 50%, p<.01). In regressions, self-reported shoulder pain was significantly associated with working above shoulder height (OR=1.5, CI 1.0-2.4), and neck symptoms with working with a bent neck (OR=2.1, CI 1.3-3.4), with a protective effect from high supervisor support (OR=0.5, CI 0.2-1.0). CONCLUSION: Risk factors and both self-reported and physician-diagnosed neck and shoulder symptoms increase in frequency from students to experienced hygienists, and students have higher prevalence if they are also dental assistants.

A pilot study of hand and arm musculoskeletal disorders in dental hygiene students.

PURPOSE: This study was designed to determine the relationship between musculoskeletal disorder symptoms and vibration in dental hygiene students as a pilot for a larger scale study. METHODS: A custom-designed questionnaire was distributed to three intact student groups: those accepted for admission, those at the end of the first year, and graduating students at the end of the second year. Data were analyzed using tabular and multivariate analysis. Students increased their use of ultrasonic instruments from 0.2 to 2.8 to 7.3 hours per week over the three years. Dental hygiene students with symptoms of numbness in the upper extremities used ultrasonic scalers a mean of 8.2 hours per week compared to 2.8 hours of use by students with no upper extremity numbness. These students also used manual instruments 10.1 hours and 4.8 hours per week, respectively. RESULTS: Logistic regression revealed a significant association between hours of use of ultrasonics and upper extremity numbness/tingling, with an odds ratio of 1.10 for each increased hour of use (95% CI 1.01-1.19; chi-square = 4.9). A similar result was found for manual instrument use. CONCLUSION: Results indicate that musculoskeletal disorder symptoms may increase with the use of ultrasonic and/or manual instruments.