Dental hygiene students are taught how to hold and use instruments during dental hygiene procedures. I still remember being taught to “rock, rock, and roll using a modified pen grasp.” During a full day of patient care, we grip instruments in both hands with our thumbs, index, and middle fingers. Our dominant hand will be rocking and rolling while our non-dominant hand is retracting cheeks, lips, and tongues.
All of this gripping and repetitive movement can lead to thumb carpometacarpal osteoarthritis (CMC OA). CMC OA is characterized by the erosion of joint cartilage, swelling, and pain, most common at the base of the thumb.2 It’s estimated that CDC OA affects 5.8% of men and 7.3% of women in their 50s and 33.1% of men and 39% of women in their 80s.1 As dental hygienists, the repeated gripping, twisting, and turning of instruments with the thumb and fingers that we do during patient care may worsen the arthritis of this joint.3
There appears to be scant research on CMC OA and dental hygienists. But generally, the incidence of osteoarthritis in female dentists tends to surpass that of male dentists as female dentists approach middle age.4
Use Upper Body Mechanics
Many of us have come across exercises for hand health or tips on choosing and using dental hygiene instruments to strengthen and protect our hands. However, we may not think about how to use our hands properly when we are at home doing basic daily tasks.
I consulted with Beth Weiss, OTL, CHT, a certified hand therapist for Mills-Peninsula Medical Center in San Mateo, California. According to Ms. Weiss, the goal is to decrease thumb use for basic activities such as opening jars and carrying objects such as shopping bags with thumbs straight and pinched. Try to use your little, middle, and ring fingers more than your thumbs and index fingers for maximum grip power.
If the palm of the hand is facing down and you grab objects with the thumb side of your hand, then you are not in the position of strength of the arm, and you are setting yourself up for strain throughout the whole arm and hand. Instead, try grabbing objects with your middle, ring, and little fingers tightened and the palm of your hand either facing up or in a neutral position (hand in line with the wrist). Keep your thumb slightly flexed. The straighter the thumb, the more likely you will use it to grip objects. It is important to utilize the power of your upper body to decrease reliance on a pinch grip from the thumb and index fingers.
Tips for using the upper body for strength:
- Keep your elbows pointing down and close to the rib cage when carrying and lifting.
- Grab objects from the bottom with little fingers pointing to the ground and elbows rotated towards your body.
- The palms of the hands should be in the up or neutral position.
- Keep thumbs slightly flexed. Avoid straight thumbs.
- Use your last three fingers to grip. Avoid using the thumbs and index fingers for reaching and gripping objects.
A helpful video for properly using hand positions can be viewed here. While the entire video contains helpful hints on proper hand positions, the instructor, Beth Weiss, OTL, CHT, provides tips for remembering to use a neutral position to grasp items at the 6:45 mark.
Protecting Hands at Work
In addition to practicing proper use of the hands at home, dental hygienists may find it helpful to practice patient positioning, clinician, and patient chair position outside of the dental office so that when they are at work, the positions will feel more natural. The patient chair could be in a supine position with both clinician and patient’s chairs adjusted so that the clinician’s thighs can move freely beneath the patient’s chair, allowing access for a seven to 12:30 o’clock position (for right-handers). This will help the dental hygienist to maintain a neutral position for the hands and body.5
Tips for maintaining hand health at work include:6,7
- Maintain a neutral hand position. Avoid pinching with the thumb and index finger.
- Use textured handled instruments with larger diameters.
- Use sharp instruments to decrease the force needed for deposit removal.
- Consider cordless instruments to help eliminate resistance from power cords.
- Take mini-breaks to stretch whenever possible.
The bottom line is that, whether at work or home, frequent or heavy lifting of objects using prolonged and awkward postures poses risks to the hands. It is wise to limit the intensity, frequency, and duration of finger and wrist movements in order to limit risks of damage to our all-important hands (and thumbs).
Before you leave, check out the Today’s RDH self-study CE courses. All courses are peer-reviewed and non-sponsored to focus solely on high-quality education. Click here now.
Listen to the Today’s RDH Dental Hygiene Podcast Below:
- May Clinic Staff. (2022, June 16). Thumb Arthritis. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/thumb-arthritis/symptoms-causes/syc-20378339
- Van der Oest, M.J.W., Duraku, L.S., Andrinopoulou, E.R., et al. The Prevalence of Radiographic Thumb Base Osteoarthritis: A Meta-Analysis. Osteoarthritis and Cartilage. 2021; 29(6): 785-792. https://www.oarsijournal.com/article/S1063-4584(21)00634-8/fulltext
- Reducing Hand Pain. (n.d.). American Dental Association. https://www.ada.org/en/resources/practice/wellness/reducing-hand-pain
- Solovieva, S., Vehmas, T., Riihimäki, H., et al. Hand Use and Patterns of Joint Involvement in Osteoarthritis. A Comparison of Female Dentists and Teachers. Rheumatology. 2005; 44(4): 521-528. https://doi.org/10.1093/rheumatology/keh534
- Gupta, A., Bhat, M., Mohammed, T., et al. Ergonomics in Dentistry. International Journal of Clinical Pediatric Dentistry. 2014; 7(1), 30-34. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4144062/
- Sanders, M.A., Michalak-Turcotte, C. Strategies to Reduce Work-Related Musculoskeletal Disorders in Dental Hygienists: Two Case Studies. J Hand Ther. 2002; 15(4): 363-374. https://www.sciencedirect.com/science/article/pii/S0894113002800084
- Stone, R. (2019, July 16). Ergonomic Adjustments Can Foster Improved Hand and Wrist Health. Zyris. https://www.zyris.com/ergonomics-for-hand-wrist-health/