OSHA Final Exam Questions and Correct
Answers|ERGONOMICS & PREVENTION OF
MUSCULOSKELETAL DISORDERS.
What is ergonomics?
The science of adjusting the design of tools, equipment, tasks, and environments for
safe, comfortable, and effective human use.
Define neutral position.
the ideal positioning of the body while performing work activities and is associated with
decreased risk of musculoskeletal injury.
List the ideal neutral positions.
-forearms and thighs parallel to floor.
-weight evenly balanced.
-hip angle of 90 degrees.
-seat positioned low enough so that heels of feet are flat on floor.
Describe neutral wrist position.
-wrist straight.
-forearm and hand in same horizontal plane.
-palm open and relaxed.
-thumb, middle, and index fingers held in a rounded shape.
-light finger pressure against instrument handle.
-ring finger advanced ahead of other fingers in the grasp.
The ______ and ______ are the hygienists greatest tool.
hand and wrist
Describe neutral neck position.
-head tilt of 0 to 15 degrees.
-line from eyes to treatment area should be as near to vertical as possible.
-AVOID tipping head too far forward or tilting to one side.
Describe neutral back position.
-leaning forward slightly from waist or hips.
-trunk flexion of 0 to 20 degrees.
-AVOID overflexion of the spine (curved back).
Describe neutral shoulder position.
-shoulders in horizontal line.
-weight evenly balanced when seated.
-AVOID lifting shoulders towards ears, hunching shoulders forward, or sitting with
weight on one hip.
Describe neutral upper arm position.
-upper arms hang parallel to long axis of torso.
-elbows at waist level, held slightly away from body.
-AVOID greater than 20 degrees of elbow abduction away from body and holding
elbows above waist level.
Describe neutral forearm position.
, -parallel to floor.
-raised or lowered by pivoting at elbow joint.
-AVOID angle between forearm and upper arm of less than 60 degrees.
Describe neutral hand position.
-little finger side of palm slightly lower than thumb side of palm.
-wrist aligned with forearm.
-AVOID thumb side of palm rotated down so that palm is parallel to floor and do not
bend hand or wrist up or down.
What should you avoid with the wrist?
-bending wrist and hand down toward palm (flexion).
-bending wrist and hand up and back (extension).
-bending wrist toward thumb (radial deviation).
-bending wrist toward little finger (ulnar deviation).
What is the most common positioning error?
having patient too high
Describe the proper positioning in relation to the patient.
-sit alongside patient with arms against your sides and crossed at your waist.
-the patients open mouth should be BELOW the point of your elbow.
-with the patient in this position you can reach the mouth without placing stress on
shoulders and arms.
Define supine position.
the position of the patient during dental treatment, with the patient lying on his or her
back in a horizontal position and the chair back nearly parallel to the floor
The patient's heels should be slightly __________ than the tip of the nose.
higher
The chair back should be ________ for maxillary treatment areas, and
___________ for mandibular treatment areas.
parallel to floor for maxillary; raised slightly for mandibular
The top of the patient's head should be even with what?
the upper edge of headrest
For mandibular areas, ask patient to open mouth and tilt head ___________.
downward
For maxillary areas, ask patient to open mouth and tilt chin ______.
up
How should the bracket table be positioned?
slightly above patient's body so that you can easily see the instruments on the tray
How should the dental light be positioned?
at arms length
Work-Related Musculoskeletal Disorder (WMD)
an injury affecting the musculoskeletal, peripheral nervous, and neurovascular systems
What is Work-Related Musculoskeletal Disorder (WMD) caused by?
-prolonged repetitive, forceful, or awkward movements.
-poor posture.
-ill fitting chairs and equipment.
-fast paced workload.
What results from Work-Related Musculoskeletal Disorder (WMD)?
Answers|ERGONOMICS & PREVENTION OF
MUSCULOSKELETAL DISORDERS.
What is ergonomics?
The science of adjusting the design of tools, equipment, tasks, and environments for
safe, comfortable, and effective human use.
Define neutral position.
the ideal positioning of the body while performing work activities and is associated with
decreased risk of musculoskeletal injury.
List the ideal neutral positions.
-forearms and thighs parallel to floor.
-weight evenly balanced.
-hip angle of 90 degrees.
-seat positioned low enough so that heels of feet are flat on floor.
Describe neutral wrist position.
-wrist straight.
-forearm and hand in same horizontal plane.
-palm open and relaxed.
-thumb, middle, and index fingers held in a rounded shape.
-light finger pressure against instrument handle.
-ring finger advanced ahead of other fingers in the grasp.
The ______ and ______ are the hygienists greatest tool.
hand and wrist
Describe neutral neck position.
-head tilt of 0 to 15 degrees.
-line from eyes to treatment area should be as near to vertical as possible.
-AVOID tipping head too far forward or tilting to one side.
Describe neutral back position.
-leaning forward slightly from waist or hips.
-trunk flexion of 0 to 20 degrees.
-AVOID overflexion of the spine (curved back).
Describe neutral shoulder position.
-shoulders in horizontal line.
-weight evenly balanced when seated.
-AVOID lifting shoulders towards ears, hunching shoulders forward, or sitting with
weight on one hip.
Describe neutral upper arm position.
-upper arms hang parallel to long axis of torso.
-elbows at waist level, held slightly away from body.
-AVOID greater than 20 degrees of elbow abduction away from body and holding
elbows above waist level.
Describe neutral forearm position.
, -parallel to floor.
-raised or lowered by pivoting at elbow joint.
-AVOID angle between forearm and upper arm of less than 60 degrees.
Describe neutral hand position.
-little finger side of palm slightly lower than thumb side of palm.
-wrist aligned with forearm.
-AVOID thumb side of palm rotated down so that palm is parallel to floor and do not
bend hand or wrist up or down.
What should you avoid with the wrist?
-bending wrist and hand down toward palm (flexion).
-bending wrist and hand up and back (extension).
-bending wrist toward thumb (radial deviation).
-bending wrist toward little finger (ulnar deviation).
What is the most common positioning error?
having patient too high
Describe the proper positioning in relation to the patient.
-sit alongside patient with arms against your sides and crossed at your waist.
-the patients open mouth should be BELOW the point of your elbow.
-with the patient in this position you can reach the mouth without placing stress on
shoulders and arms.
Define supine position.
the position of the patient during dental treatment, with the patient lying on his or her
back in a horizontal position and the chair back nearly parallel to the floor
The patient's heels should be slightly __________ than the tip of the nose.
higher
The chair back should be ________ for maxillary treatment areas, and
___________ for mandibular treatment areas.
parallel to floor for maxillary; raised slightly for mandibular
The top of the patient's head should be even with what?
the upper edge of headrest
For mandibular areas, ask patient to open mouth and tilt head ___________.
downward
For maxillary areas, ask patient to open mouth and tilt chin ______.
up
How should the bracket table be positioned?
slightly above patient's body so that you can easily see the instruments on the tray
How should the dental light be positioned?
at arms length
Work-Related Musculoskeletal Disorder (WMD)
an injury affecting the musculoskeletal, peripheral nervous, and neurovascular systems
What is Work-Related Musculoskeletal Disorder (WMD) caused by?
-prolonged repetitive, forceful, or awkward movements.
-poor posture.
-ill fitting chairs and equipment.
-fast paced workload.
What results from Work-Related Musculoskeletal Disorder (WMD)?
