The effect of dental instruments design on grip strength

Introduction: Dentist work requires comfort and visibility, which sometimes causes an incorrect, maladjusted, and static posture, affecting mostly the upper limbs. It is due to prolonged work that oral health professionals are more susceptible to developing musculoskeletal disorders (MSDs) of the hand and wrist. This work involves excessive flexion positions of the wrist/hand, mechanical stress associated with instrument manipulation, and force applied during dental procedures. The propose of this study was to evaluate and analyze the variation of grip strength in dental students. We also pretend to evaluate the incidence of signs and symptoms of MSDs. Materials and Methods: A clinical dental procedure was simulated using instruments of different design on phantoms to evaluate the palmar grip. Grip strength was measured with a dynamometer. The Nordic Musculoskeletal Questionnaire was conducted to assess the incidence of symptoms of MSDs. Results: The most prevalent symptoms in this population were neck, lower back, and shoulder pain. During the procedure, 43 participants found the ergonomic curette more comfortable. After scraping with the metallic curette, a lower palmar grip strength was observed. Women have a higher incidence of MSDs and lower grip strength. Conclusion: After the use of ergonomic periodontal curette to root scaling, participants presented higher mean grip force (290 ± 107 N) than after the use of metal handle periodontal curette (273 ± 105 N). Instruments with a larger diameter and lower weight are more ergonomic and require less grip force. Participants should transform and improve clinical habits to promote better working conditions and decrease MSDs.