Variation in work tasks in relation to pinch grip strength among middle-aged female dentists.

OBJECTIVES: We aimed to investigate the relationship of task variation during dental work history with pinch grip strength among dentists. METHODS: We measured pinch grip strength among 295 female Finnish dentists aged 45-63 years. Variation in dental work tasks during work history was empirically defined by cluster analysis. Three clusters of task variation emerged: low (most work time in restoration treatment/endodontics), moderate (about 50% in the former and 50% in prosthodontics/periodontics/surgery), and high (variable tasks including administrative duties). Hand radiographs were examined for the presence of OA in the wrist and each joint of the 1-3rd fingers. Information on hand-loading leisure-time activities, and joint pain was obtained by questionnaire. Glove size was used as a proxy for hand size. BMI (kg/m2) was based on measured weight and self-reported height. RESULTS: Dentists with low variation of work task history had an increased risk of low pinch grip strength in the right hand (OR 2.3, 95% CI 1.2-4.3), but not in the left (1.13, 0.62-2.08), compared to dentists with high task variation, independent of age, hand size, hand-loading leisure-time activities, BMI and symptomatic hand OA. CONCLUSION: The dentists with the most hand-loading tasks were at an increased risk of low pinch grip strength, independent of e.g. symptomatic hand OA. It is advisable among dentists to perform as diverse work tasks as possible to reduce the risk of decreased pinch grip strength.

Determinants of incident and persistent finger joint pain during a five-year followup among female dentists and teachers.

OBJECTIVE: To investigate the association of radiographic finger osteoarthritis (OA), hand use, and lifestyle factors with incident and persistent finger joint pain among female dentists and teachers. METHODS: Random samples of female dentists (n = 295) and teachers (n = 248) ages 45-63 years were examined by radiography for the presence of finger joint OA. Body weight was measured. Information on finger joint pain during the past 30 days, height, smoking, and leisure-time hand activity was collected by questionnaire. Five years later, 482 women (89%; 65% still active occupationally) responded to a survey on finger joint pain. RESULTS: The incidence and persistence of finger joint pain were higher among the subjects with OA compared to those without OA. The relative risk (RR) of incident pain in the first through the third fingers was 1.8 (95% confidence interval [95% CI] 1.2-2.7) in the right hand and the RR in the left hand was 3.0 (95% CI 2.0-4.6), allowing for age, occupation, and lifestyle factors. The corresponding figures for the fourth and fifth fingers were RR 2.3 (95% CI 1.4-3.8) in the right and RR 1.9 (95% CI 1.1-3.5) in the left hand. Regarding persistent pain, the RRs varied between 2.4 and 5.4. Body mass index, smoking, or leisure-time hand activity were not associated with pain. The dentists tended to have a higher incidence of pain in the first through the third fingers of the right hand compared with the teachers. CONCLUSION: Radiographic finger joint OA was a significant determinant of both persistent and incident finger joint pain in a 5-year followup among middle-aged women. Hand use may modify the association between radiographic OA and finger joint pain.