PT  - JOURNAL ARTICLE
AU  - McCombs, Gayle
AU  - Russell, Daniel M.
TI  - Comparison of Corded and Cordless Handpieces on Forearm Muscle Activity, Procedure Time and Ease of Use during Simulated Tooth Polishing
DP  - 2014 Dec 01
TA  - American Dental Hygienists Association
PG  - 386--393
VI  - 88
IP  - 6
4099  - http://jdh.adha.org/content/88/6/386.short
4100  - http://jdh.adha.org/content/88/6/386.full
SO  - J Dent Hyg2014 Dec 01; 88
AB  - Purpose: Dental professionals suffer from a high prevalence of work-related musculoskeletal disorders (MSD). Dental hygienists in particular have a high prevalence of pain in the forearms and hands. The objective of this study was to compare 1 cordless handpiece to 2 corded handpieces during simulated tooth polishing in terms of the muscle loads (recorded as electromyography (EMG) activity), duration of polishing procedure, and dental hygienist opinion about ease of use. Methods: EMG was used to quantify muscle electrical activity of 4 forearm muscles during simulated dental polishing with 2 corded handpieces (HP-A and HP-B) and 1 cordless handpiece (HP-C). A convenience sample of 30 dental hygienists (23 to 57 years of age) with 1 to 20+ years of clinical practice experience completed the study. Each participant spent approximately 5 minutes polishing 3 predetermined teeth in each of the 4 quadrants. The sequence of the handpieces was randomly assigned. At the end of the study, participants completed a subjective end user evaluation of handpiece preference. Results: Muscle activity levels of 10th, 50th and 90th percentiles did not differ significantly between the 3 handpieces tested (p>0.05). However, total muscle workload (integrated EMG) was lowest for the cordless handpiece (HP-C), but this was only significantly less than HP-A (p<0.05). Polishing using the cordless handpiece (HP-C) (M=257 seconds, SD=112 seconds) took significantly less time than either the HP-A corded (M=290 seconds, SD=137 seconds) or HP-B corded handpiece (M=290 seconds, SD=126 seconds) (p<0.05). Overall, 50% of the study participants preferred the cordless handpiece, 37% preferred HP-A and 13% preferred HP-B (p<0.05). Conclusion: Use of the cordless handpiece reduced the duration of polishing, which in turn led to less total muscle activity, but not muscle intensity. Overall, dental hygienists preferred the cordless handpiece.