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Ergonomics and Physical Well-Being - Working strategies for coping with and preventing cumulative trauma disorders

Jan. 1, 2004
Part 2: Prevention Exercises

Part 2: Prevention Exercises

Part 1 appeared in November/December 2003 Woman Dentist Journal

Proper posture is vital so that the body is supported by the spine, not the muscles, ligaments, and surrounding soft tissue. Strong postural muscles of the trunk and shoulders stabilize the body, allowing the arms and hands to perform detailed tasks. Proper posture is attained when the ears are directly over the shoulders and in line with an imaginary line that extends from the shoulder through the hips to the ankle.9 To assume this position, take a deep breath, raising the top of the sternum as high as possible. Exhale, but keep that point raised. This should put the body into a neutral, well-supported position. Experienced practitioners may have to consciously move the chin back and rotate the pelvis under to achieve the straight postural line from ear to ankle. Consciously finding this position several times during the day will help the body remember the position and reproduce it easily. Good body posture that is sustained by stretching and strength-building programs is crucial to minimizing, if not preventing, cumulative trauma disorders (CTDs).2,9

Many authors advocate stretching throughout the day and even at chairside.2,3,9,10 Here are some tips that will help you have energy at the end of the day. Include your team members in these exercises to support each other:

  • Frequent, brief pauses to counteract sustained postures and shift muscle groups are better than lengthy, infrequent workouts.3,9
  • During a long dental procedure, give yourself and the patient (and the patient's TMJ) a break! During that break, take a few moments to move your flexed arms back and forth locomotive-fashion to loosen muscles and break the stress cycle. Extend your legs out from under the chair, rotate your wrists, and stretch your neck, arms, and back.
  • Remember those ballet postures by performing similar movements on each side. Performing a movement only on one side causes muscle tightness and imbalance. An equal movement should always be performed on the opposite side. Extending and rotating the wrists counteracts the sustained flexion of dental procedures. Carefully extend your neck backward or down and over to an opposite position than usually maintained to shift those muscle groups.
  • Pull your elbows back while pushing your chest forward to stretch chest muscles away from the cramped position. This will strengthen the muscles that pull the insertions of the scapulas into a supportive position.

Between patients, you can perform several short exercises to strengthen and counteract long-term sustained postures and further shift muscle groups:

  • the corner stretch
  • elastic-assisted rowing
  • shoulder flexion and abduction
  • butterflies

The corner stretch requires only an unobstructed corner of the room. Stand with toes approximately one-and-a-half feet from the corner. Place hands flat against either wall at shoulder height. Maintain the body in a straight line and allow the body to tilt into the corner until a pleasant stretch across the chest is perceived. Hold five to seven full seconds for 10 repetitions. (Figures 1 and 2)

The corner stretch - Figure 1
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The corner stretch - Figure 2
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Assisted rowing can be done with either bungees or Thera-band® products ( made by the same company that makes the rubber dam. Secure Thera-bands either around the doorknobs of an open door if standing or across the bottoms of your feet if sitting with legs extended. Pull your arms back in a rowing motion while keeping your back straight to strengthen the trapezius and other muscles supporting the scapula. (Figure 3) Instead of rapid rowing, a long, sustained movement to the count of five seconds in each direction is a better workout. Do 10 to 20 repetitions.

Assisted rowing - Figure 3
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Shoulder flexion and abduction is accomplished by standing with your back to a wall. Feet should be about six to nine inches from the wall with knees slightly bent, allowing the lower back to remain flat against the wall's surface. With elbows bent at about a 90-degree angle, extend your arms out from the body, keeping forearms and the backs of your hands flat against the wall. Continuing to keep forearms flat against the wall, raise your upper arms slowly to the count of five with hands approaching one another over the head, then lower to original position. (Figures 4 and 5) Start out with five repetitions and work up to 10 repetitions.

Shoulder flexion and abduction - Figure 4
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Shoulder flexion and abduction - Figure 5
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Butterflies (or 'flies) are achieved with a movement similar to the way a butterfly moves its wings. Stand with your feet slightly apart, knees slightly bent, head down, and torso approaching a 90-degree angle at the hip. Keeping your arms straight, raise them to shoulder height at a 90-degree angle to the body. Next, raise your arms at a 45-degree angle from your head, followed by raising your arms at a 135-degree angle from your head. Do 10 repetitions in each position to the count of five each time. (Figures 6, 7, and 8)

Butterflies - Figure 6
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Butterflies - Figure 7
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Butterflies - Figure 8
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The last — but not least — strategy is a stress-management program adhered to faithfully. Many people in business for themselves develop more of a Type A personality that is intensified by the precise nature of dental procedures performed within constant time limits.2 Practicing yoga, meditation, aerobics, an enjoyable hobby, or arranging for regular massage often helps the body rebound from daily stress by focusing energy on one's own physical and mental well-being.10 Yes, yoga is good for you!

As the world continues to march at a faster and faster pace driven by rapid increases in technology, remember to nurture yourself as the gentle being you are who deserves creative or spiritual breaks from the monotony and tension of production.

We chose dentistry as a profession because we enjoy working with people and delight in promoting oral health with our patients. We must be sure, however, that we also take measures to maintain our own health and well-being. Knowledge of ergonomics, posture, maintenance of key muscle groups, and stress management can aid us in accomplishing our goal of personal well-being to achieve the best health for our patients.3

Note: Special thanks to Rodger Henning, PT, for all his help with suggested exercises!


  1. White SW. Ergonomics U How does dentistry fit you? WDJ 2003; 1(1):58-62.
  2. Wann O, Canull B. Ergonomics and dental hygienists. Contemporary Oral Hygiene 2003; 3(5):16-22.
  3. Andrew N, Vigoren G. Ergonomics: muscle fatigue, posture, magnification and illumination. Compendium 2002; 23(3):261-272.
  4. Graham C. Ergonomics in dentistry: Part 1. Dentistry Today 2002; 21(4):98-103.
  5. Rucker LM, Sunell S. Ergonomic risk factors associated with clinical dentistry. J of CDA 2002; 30(2):139-148.
  6. Pollack R. Dento-ergonomics: the key to energy-saving performance. J of CDA 1996; 24(4):63-68.
  7. Rucker LM. Technology meets ergonomics in the dental clinic: new toys for old games. J Am Coll Dent 2000; 67(2):26-28.
  8. Liskiewicz T, Kerschbaum WE. Cumulative trauma disorders: an ergonomic approach for prevention. J of Dental Hygiene 1997; 71(4):162-167.
  9. Valachi B. Improving your musculoskeletal health. Dimensions of Dental Hygiene June/July 2003:20-26.
  10. Valachi K, Valachi B. Position yourself in 2003. Dental Products Report 2002; 36(12):50-54.
  11. Murphy DC. Ergonomics and dentistry. New York St Dent Jour 1997; 63(7):30-34.
  12. Mito RS, Fernandez K. Why is ergonomics an issue in dentistry? J of CDA 2002; 30(2):133-134.
  13. Yoser AJ, Mito RS. Injury prevention for the practice of dentistry. J of CDA 2002; 30(2):170-176.
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Judith A. Porter, DDS
Dr. Porter, a general dentist, has built two solo practices during her career, taking time off in between to raise her children. She obtained a master's in secondary education in 1999 and an EdD in 2003. She is currently on the faculty at the University of Maryland Dental School.