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An applied science concerned with designing and arranging things people use so that the people can do work most efficiently and comfortably. …

An applied science concerned with designing and arranging things people use so that the people can do work most efficiently and comfortably.

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  • 2. NOW IT’S THE ERA OF designing tools, equipments, work stations and tasks to fit the work ….. NOT worker to the job.
  • 3. What is Ergonomics?  An applied science concerned with designing and arranging things people use so that the people can do work most efficiently and comfortably. IN SHORT…… In Greek, “Ergo,” means work and, “Nomos,” means natural laws or systems
  • 4. WHY SHOULD DENTAL STUDENTS AND DENTISTS CARE?  Ergonomics might positively impact dentists throughout their professional lifespan.  More than 70 percent of dental students reported neck, shoulder and lower back pain by their third year of dental school issue of January 2005
  • 5.  Dentists and dental students often assume awkward physical positions while providing treatment ...
  • 6. REASONS FOR EARLY RETIREMENT AMONG DENTISTS •MSD Musculoskeletal Disorder (29.5%) •CVS Cardio Vascular Diseases (21.2%) •NEUROTIC SYMPTOMS(16.5%) •TUMORS(7.6%) •DISEASE OF NERVOUS SYSTEM(6.1%) Source: Burke et al., 1997
  • 7. One term to get to know is Musculoskeletal Disorder(MSD). Fortunately, good ergonomic practices can drastically reduce the likelihood that an MSD will slow you down.
  • 8. Musculoskeletal Disorders (MSDs)  Include a group of conditions that involve nerves, tendons, muscles, and supporting structures such as intervertebral discs Severity of Symptoms Mild periodic Severe chronic & debilitating conditions
  • 9. MSD SYMPTOMS AMONG DENTISTS 0% 10% 20% 30% 40% 50% 60% 70% 80% Neck Shoulder Upper Back Lower Back Elbows Wrists/ Hands Knees %Reporting Body Part Males Females Source: Finsen et al., 1998
  • 10. TYPES OF MSDS  Neck and Shoulder Disorders Cervical Spondylosis ◦ Thoracic Outlet Syndrome Rotator Cuff Tendinitis/Tears Myofacial pain disorder
  • 11.  Back Disorders ◦ Herniated Spinal Disc ◦ Lower Back Pain ◦ Sciatica
  • 12. HAND AND WRIST DISORDERS Carpal tunnel syndrome Trigger fi nger Swelling Ganglion cysts non-cancerous, fl uid-fi lled lumps Tendonitis/Tenosynovi tis Infl ammation or thickening
  • 13. MSDs Signs Symptoms  Decreased range of motion  Deformity  Decreased grip strength  Loss of muscle function  Pain  Numbness  Tingling  Burning  Cramping  Stiffness
  • 14. USAF Dental Evaluation & Consultation Service What Factors Contribute to MSDs?  Forceful hand exertions ◦ Grasping small instruments for prolonged periods ◦ Forceful squeezing/release of instruments  Repetitive movements—e.g., scaling, root planing, polishing
  • 15. What Factors Contribute to MSDs?  Fixed or awkward postures ◦ Neck, back, shoulder posture ◦ Hand/wrist positions ◦ Standing/sitting ◦ Operatory organization ◦ Patient positioning
  • 16. What Factors Contribute to MSDs?  Prolonged use of vibrating hand tools— dental handpieces, laboratory equipment
  • 17. Contributing Factors for MSDs  A risk factor is not always a causation factor  The level of risk depends on ◦ Amount ◦ duration ◦ Level of exposure
  • 18. APPLYING ERGONOMICS PRINCIPLE TO WORK •Tools / Instruments •Work stations • Work practices
  • 19. USAF Dental Evaluation & Consultation ServiceApplying Ergonomics to Dentistry TOOL/Instrument Design  Goal: reduce force exertion; maintain hand/wrist in neutral position (no wrist bend) Holding the Wrist in a Non- Neutral Position Tight Pinch Grip: The distal index finger joint is straight Work with wrist in neutral position, when possible. Use a more relaxed grip, when possible. The distal: finger joint is slightly fl
  • 20. Applying Ergonomics to Dentistry Hand Instruments  When selecting instruments, look for ◦ Hollow or resin handles ◦ Round, textured/groove s, or compressible handles ◦ Carbon-steel construction ◦ Color-coding may make instrument identification easier
  • 21. Applying Ergonomics to Dentistry Dental Handpieces  When selecting handpieces, look for ◦ Lightweight, balanced models ◦ Sufficient power ◦ Built-in light sources ◦ Angled vs. straight-shank ◦ Pliable, lightweight hoses (extra length adds weight) ◦ Swivel mechanisms
  • 22. Applying Ergonomics to Dentistry Provide Sufficient Space  Permanently place equipment used in every clinical procedure within comfortable reach (within 20 inches of the front of the body)  Use mobile carts for less commonly used equipment ◦ Allows convenient positioning when required
  • 23. LIGHTING GOAL: Produse even ,shadow- free, color- corrected illumination concentrated on operating field •The overhead light switch should be readily accessible •Hand mirrors can be used to provide light intra orally •Use of fibreoptics for hand pieces add concentered lighting to operating field
  • 24. MAGNIFICATION GOAL: improve neck posture, provide clearer vision •Working distace •Depth of field •Eye loupes single lens multi lens telescopic loupes
  • 25. Applying Ergonomics to Dentistry Operator Chair  Goal: promote mobility and patient access; accommodate different body sizes  Look for: ◦ Stability ◦ Lumbar support ◦ Hands-free seat height adjustment ◦ Fully adjustable
  • 26. PATIENT CHAIR GOAL: Should promote patient comfort, maximise patient access •Look for stability •Fully adjustable head rest •Hands free operaion •Support head torso feet
  • 27. Applying Ergonomics to Dentistry Work Practices  Goal: maintain neutral posture; reduce force requirements  Potential strategies ◦ Ensure instruments are sharpened, well-maintained ◦ Use automatic handpieces instead of manual instruments wherever possible ◦ Use full-arm strokes rather than wrist strokes
  • 28. Applying Ergonomics to Dentistry Reduce Physical Effort  Improve neck posture and clear vision
  • 29. GOAL : Avoid static or awkward postures Eye 14 16 inches away from patients oral cavity Shoulder relaxed and not elevated Elbows elevated not more than 30 degrees. Should adjust patient chair when accessing different quadrants Sit tall ,legs seperatedAdjust the height of your seat so that your feet can be flat on the fl oor and your knees are a little below the level of your hips (your thighs are slanted slightly downward). Allow the thighs to be
  • 30. PATIENTS  Traditionally placed in supineposition back of dental chair almost parallel to the ground
  • 31. Applying Ergonomics to Dentistry Reduce Physical Effort  Use reasonable operating forces and minimal repetitions reduces overall physical effort required by a task  Minimize sustained effort ◦ Brief but frequent rest pauses can minimize fatigue and enhance productivity ◦ Try to incorporate a variety of different activities to shift musculoskeletal demands from one part of the body to another
  • 32. Goal: provide sufficient recovery time to avoid muscular fatigue Potential strategies • Increase treatment time for more difficult patients • Alternate heavy and light calculus patients within a schedule • Vary procedures within the same appointment • Shorten patient’s recall interval SHEDULING
  • 33. Applying Ergonomics to Dentistry Personal Protective Equipment  Glasses ◦ Lightweight, clean, well- fitted ◦ Magnifying lenses and head lamps are encouraged  Clothing ◦ Fit loosely, lightweight, pliab le
  • 34. Applying Ergonomics to Dentistry Personal Protective Equipment  Gloves ◦ Be of proper size, lightweight, and pliable ◦ Should fit hands and fingers snugly ◦ Should not fit tightly across wrist/forearm
  • 35.  And because even dental students have a life outside of dentistry, everyday habits can add to the stress on your body and well- being. avoid “Blackberry Thumb.” heavy, plastic bag can concentrate stress in a small area of your hand Holding your phone between your shoulder and ear When using a computer keyboard, use the padded wrist rest Ergonomics and Everyday Life
  • 36. STRATEGY METHOD/RATIONALE Magnification Magnification loupes Patient positioning Appropriate chair position, patient head anguations Operator positioning Use of clock positions, avoiding static postures, seated dentistry Assistant positioning Seated above operator eye level, hips and thighs parallel with patients shoulders,avoiding static postures Equipment Designed and positioned to minimize bending and reaching, using lumbar support Instruments Larger diameter handle, textured grip, balanced weight Maintain Good Health Exercise, meditation ,regular breaks SUMMARY
  • 37. RECOMMENDATIONS Exercise and fitness is an important element of overall health and prevention of musculoskeletal disorders. Research has shown that
  • 38. excercises The un-twister Legs in tripod position; bend to left side. Rest your left elbow on left knee. Stretch right arm overhead and look towards the ceiling. Hold for 2-4 breath cycles Trunk rotation Sit tall. Cross right leg over left leg. Place left forearm on right thigh and turn trunk to the right. Hold for 2-4 breath cycles The reversal Support wrists on hips and slowly lean backward. Do not overextend the head. Hold for 2-4 breath cycles
  • 39. CONCLUSION  Ergonomics and You  Two dental students may be exposed to the same risks, at the same degree of intensity, and one will develop an MSD and the other will not.  We dont know why? But its true…  A poor ergonomic choice may impact you today or even a few years down the roads. Risk factors for MSDs affect everyone differen