Ergonomics

Question 1

What percent of dentists who retire early are forced to due to musculoskeletal disorders?

Answer 1

30%

Question 2

How much money could be lost if a dentist is required to retire even 5 years early?

Answer 2

$1,000,000

Question 3

How many hours in a lifetime of working is a dentist in tense/distorded positions?

Answer 3

60,000 hours

Question 4

How much money is lost per day due to muscular issues?

Answer 4

$800-$1400

Question 5

What are the goals of ergonomics?

Answer 5

• Prevent the standard of care to the patient
• Increase safety and productivity
• Enhance performance by elimanating unnecessary effort
• Improve the standard care of the patient

Question 6

What are the symptoms of MSDs?

Answer 6

 Excessive fatigue in the shoulders
and neck
 Tingling, burning or other pain in
arms
 Weak grip, cramping of hands
 Numbness in fingers and hands
 Clumsiness and dropping of objects
 Hypersensitivity in hands and
fingers

Question 7

What is a micro trauma?

Answer 7

microscopic damage that occurs daily to certain parts of your musculoskeletal system

Question 8

What are the most common CTDs?

Answer 8

chronic low back pain
tension neck syndrome
trapezius myalgia

Question 9

What is chronic low back pain caused by?

Answer 9

poor seated posture and
weak stabilizing trunk muscles

Question 10

What is tension neck syndrome caused by?

Answer 10

result of a forward head posture

Question 11

What is trapezius myalgia caused by?

Answer 11

pain, tenderness from sustained contraction in upper trapezius muscle. Often from chronic elevation of the shoulders

Question 12

What is rotor cuff impingement caused by?

Answer 12

shoulder pain from over-reaching, and a sustained arm elevation

Question 13

What is carpal tunnel syndrome caused by?

Answer 13

medial nerve compression in the wrist from a flexed wrist posture, a forceful grip and/or gripping instruments with small diameters

Question 14

What percent of dental students from all four years experience neck, shoulder, and back pain?

Answer 14

46-71%

Question 15

What percent of dental students reported pain by their 3rd year?

Answer 15

more than 70%

Question 16

What are the 3 P’s to fitness in the operatory?

Answer 16

❖ Posture
❖ Positioning
❖ Periodic Stretching

Question 17

How should you position yourself?

Answer 17

Maintain neutral position:
❖ Head at 0-20 tilt-ears over shoulders
❖ Shoulders over hips
❖ Elbows relaxed at sides
❖ Forearms parallel to the floor or slightly upward
❖ Slight curve in lower back/lordosis
❖ Hip angle >90- ideally 105-125*
❖ Feet flat on floor in tripod position

Question 18

What is a neutral seated position?

Answer 18

❖ Forearms parallel to the floor.
❖ Weight evenly balanced.
❖ Hips higher than knees-110 degrees.
❖ Seat height positioned low enough so that you are able to rest the heels of your feet on the floor.
❖ Have a tripod effect-legs and torso.

Question 19

What is a neutral neck position?

Answer 19

❖ Head tilt of 0° to 15°
❖ The line from eyes to the treatment area should be as near to vertical as possible.

Question 20

The head weighs 8-10 pounds, and for every one inch the head tilts forward, the load on neck and muscles _______

Answer 20

doubles

Question 21

What is neutral shoulder position?

Answer 21

❖ Shoulders in horizontal line.
❖ Weight evenly balanced when seated.

Question 22

What is neutral back position?

Answer 22

❖ Leaning forward slightly from the waist or hips.
❖ Trunk flexion of 0° to 20°

Question 23

What is neutral upper arm position?

Answer 23

❖ Upper arms hang parallel to the long axis of torso.
❖ Elbows at waist level held slightly away from body.

Question 24

What is a neutral forearm position?

Answer 24

❖ Parallel to the floor.
❖ Raised or lowered, if necessary, by pivoting at the elbow joint.

Question 25

How should you position the patient to maintain neutral position?

Answer 25

❖ Recline the patient: supine for maxillary, semi-supine for mandibular
❖ Adjust headrest
❖ Adjust chair height to maintain neutral position
❖ Ask patient to move head as needed
❖ Equipment placement within easy reach
❖ Light position to avoid shadowing

Question 26

What is the importance of periodic stretching?

Answer 26

• microbreaks to allow repair to microtraumas
• chairside stretching

Question 27

What are some examples of chair-side yoga stretches?

Answer 27

• hand clenching
• wrist bending
• shoulder rolls
• wing and prayer

Question 28

Exercise or physical activity of all
kinds stimulates…

Answer 28

neurogenesis (the process by which new neurons are formed in the brain), partly due to the production of Brain-Derived Neurotrophic Factor or BDNF

Question 29

What are the benefits of magnification?

Answer 29

❖ Reduce strain on your eyes
❖ Improve the quality of care and diagnostics
❖ Improve your vision via greater magnification
❖ Increased comfort via proper ergonomics

Question 30

There is significant improvement in visual acuity when using magnification in conjunction with a _________________________.

Answer 30

fiber optic light source

Question 31

What does the ADA recommend for ear protection?

Answer 31

❖ Wear ear plugs or noise-cancelling headphones while using dental equipment
❖ When selecting dental equipment, consider its noise level
❖ Have hearing tested to establish a baseline
❖ Monitor your hearing acuity on a regular basis

Question 32

What is acoustic trauma?

Answer 32

few exposures, intense sound level; ex: explosion

Question 33

What is temporary threshold shift?

Answer 33

temporary hearing change following exposure to noise; ex: concert

Question 34

What is a permanent threshold shift?

Answer 34

result of accumulation of exposure to noise repeated over years; irreversible; this is what we experience in dentistry