Ergonomics Flashcards
Explain the purpose of each element of the modified pen grasp:
- Placement of each finger
- The handle rest
- Concept of fingers functioning as a unit
The placement and use of the thumb and each finger:
The modified one grasp provides precise movements, control, and lessens musculoskeletal stresses.
• With the thumb and index being opposite from each other, the clinician has greater control. In addition, it is easier for them to roll the instrument when needed
• With the middle finger on the shank, clinicians can feel vibrations from the instrument. This is integral in calculus detection.
• The “fulcrum” ring finger provides balance, strength, and most importantly the ability to maneuver efficiently
• Pinky has no function
The handle rest:
Holding the handle away from the grip creates a weak, unstable grasp if conducted constantly
It is necessary to allow the handle to come to this position when scaling some mesial surfaces
The concept of fingers functioning as a unit:
When the fingers function as a unit, it provides strength and stability in grasp.
Define Fulcrum
Discuss it’s purposes
A Fulcrum is as a “finger rest that acts as a support beam, and is used to stabilize the clinician’s working hand during periodontal instrumentation”
The purposes of a Fulcrum are:
• Improve the precision of instrumentation
• Prevent sudden movements that could injure your patient
* Reduce muscle load to the clinicians hand
* Provide control lateral forces
* Control the length of instrument stroke
Define ergonomics
Ergonomics is an applied science to equipment design which enables individuals to maximise their productivity while also reducing fatigue and discomfort.
List 3 groups of Musculoskeletal disorders, give examples of them and list common causes for them
Neck and Shoulder disorders, e.g. muscle stiffness from keeping head down in one position for too long
Back disorders, e.g. bulging disks from incorrect seating position for extended periods at a time
Hand and wrist disorders, e.g. tendonitis
Causes: • Repetitive motions • Excessive force working motions • Static and incorrect posture • Vibrating tools
Describe and demonstrate the characteristics of Neutral Positioning for the dental clinician
Head:
* tilted between 0 -15 degrees. DO NOT tilt head too forward, not tilt head to side
Back:
* leaning forward slightly from waist or hips. AVOID curved back
Torso:
* In line with long axis. AVOID leaning or twisting torso
Shoulders:
* Even. AVOID hunching towards ears
Upper arm:
* Elbows at waist level held slightly away (20 d) from body. AVOID putting elbows
above waist
Fore arm:
* Parallel to floor. 60 - 100 d ROM is ok
Wrist:
* Little finger side of palm should be a little lower than the thumb side of the palm. AVOID palms parallel to floor
Seating positioning • Soles flat on the floor • Weight even distributed • Hips slightly higher than knees • Back of the chair (where back rests) should be 1 inch higher than front of the chair
Describe and demonstrate the characteristics of Neutral Positioning for the dental patient
Supine position
• Feet should be slightly higher than tip of nose when laying
• Back of the patients chair should be parallel to floor when treating maxillary
• When treating maxillary, the nose and chin must be level “chin up position”
• When treating mandible, chair should be slightly raised (15 d)
• Mandible: nose higher than chin “chin down position”
• The back of the patients head should be in line with the edge of the head rest
* Patients mouth should be below the point of clinicians elbow
List and describe what Ancillary Equipment may be of benefit to the Dental Operator in maintaining good posture and positioning
Magnification loupes: reduces strain because it magnifies treatment area, which prevents the need for dentist to lean forward and see (this causes back and neck strain), reduces eye strain
Loupes with Co-Axial illumination: greatly improves vision, reduces eye strain
Saddle seat: conventional seats with back rest promote slouching which compresses the vertebrae. The saddle seat is designed to promote the correct, straight posture seating position
Describe the consequences of incorrect instrument grasp and glove fit
Incorrect instrument grip:
• Incorrect finger grip: difficult to control the handle, difficult to roll
• If index and thumb collapse inward, it will lead to joint hyper mobility in hands
• An incorrect grasp will cause finger grasp to lift off/loosen
• Can cause RSI injuries: carpal tunnel, tendinitis
• If middle and ring fingers do not contact, it causes weak grasp and stresses muscles of hand
Incorrect glove fit:
• Fits tightly across palm and wrist
• Can cause numbness or pain
* Creates muscle fatigue
