title: The effect of tool handle shape on hand muscle load and pinch force in a simulated dental scaling task.
abstract: Work-related upper extremity musculoskeletal disorders, including carpal tunnel syndrome, are prevalent among dentists and dental hygienists. An important risk factor for developing these disorders is forceful pinching which occurs during periodontal work such as dental scaling. Ergonomically designed dental scaling instruments may help reduce the prevalence of carpal tunnel syndrome among dental practitioners. In this study, eight custom-designed dental scaling instruments with different handle shapes were used by 24 dentists and dental hygienists to perform a simulated tooth scaling task. The muscle activity of two extensors and two flexors in the forearm was recorded with electromyography while thumb pinch force was measured by pressure sensors. The results demonstrated that the instrument handle with a tapered, round shape and a 10 mm diameter required the least muscle load and pinch force when performing simulated periodontal work. The results from this study can guide dentists and dental hygienists in selection of dental scaling instruments.
authors.affiliation: School of Public Health, University of California, 1301 South 46th Street, Building 163, Richmond, Berkeley, CA 94804, USA.
authors.forename: Hui
authors.initials: H
authors.lastname: Dong
authors.forename: Peter
authors.initials: P
authors.lastname: Loomer
authors.forename: Alan
authors.initials: A
authors.lastname: Barr
authors.forename: Charles
authors.initials: C
authors.lastname: Laroche
authors.forename: Ed
authors.initials: E
authors.lastname: Young
authors.forename: David
authors.initials: D
authors.lastname: Rempel
mesh_terms: D000328:Adult; D003756:Dental Hygienists; D012534:Dental Scaling / Q000295:instrumentation*; D004576:Electromyography; D004867:Equipment Design; D006804:Ergonomics; D005260:Female; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D008297:Male; D009140:Musculoskeletal Diseases / Q000517:prevention & control; D009784:Occupational Diseases / Q000517:prevention & control; D012495:San Francisco