Wilkins’ Clinical Practice of the Dental
Hygienist Chapter 37 (Modules 3–8) | 150
Practice Questions & Answers with Rationales
MODULE 3 — INSTRUMENT DESIGN & BASIC
INSTRUMENTATION PRINCIPLES
Questions 1–25
1. Which component of a hand instrument is primarily grasped
by the clinician?
A. Shank
B. Working end
C. Handle
D. Terminal shank
Answer: C. Handle
Rationale: The handle is the portion of the instrument designed to
be held by the clinician and provides control during
instrumentation.
2. The working end of a periodontal instrument is designed
primarily to:
A. Provide a finger rest
B. Perform the intended clinical function
C. Connect the instrument to the operator's hand
D. Control the patient's head position
,Answer: B. Perform the intended clinical function
Rationale: The working end is the functional portion of the
instrument that contacts the tooth surface or periodontal tissues.
3. Which instrument component connects the handle to the
working end?
A. Shank
B. Blade
C. Toe
D. Face
Answer: A. Shank
Rationale: The shank connects the handle to the working end and
influences access and angulation.
4. Instrument balance is important because it helps the clinician:
A. Increase the weight of the instrument
B. Maintain control with minimal muscular effort
C. Eliminate the need for a fulcrum
D. Increase calculus formation
Answer: B. Maintain control with minimal muscular effort
Rationale: Properly balanced instruments improve control and
reduce unnecessary hand and wrist strain.
,5. An instrument with a lightweight handle is generally intended
to:
A. Increase fatigue
B. Reduce tactile sensitivity
C. Improve comfort and control
D. Prevent adaptation
Answer: C. Improve comfort and control
Rationale: Lightweight ergonomic handles can decrease muscle
strain while maintaining effective tactile control.
6. The terminal shank is particularly important because it helps
the clinician determine:
A. Patient blood pressure
B. Working-end orientation
C. Tooth color
D. Instrument sterilization temperature
Answer: B. Working-end orientation
Rationale: The terminal shank provides an important visual and
tactile reference for positioning the working end.
7. A rigid instrument shank is particularly useful when:
A. Heavy calculus must be removed
B. Only polishing is being performed
C. No tactile sensitivity is required
D. The instrument is being sharpened
, Answer: A. Heavy calculus must be removed
Rationale: Greater rigidity can provide the lateral pressure
necessary for removing tenacious deposits.
8. A more flexible shank is generally advantageous when working
on:
A. Heavy supragingival calculus only
B. Delicate root surfaces
C. The instrument handle
D. The patient's cheek
Answer: B. Delicate root surfaces
Rationale: Flexible instruments can provide better adaptation
and tactile sensitivity in areas where excessive force should be
avoided.
9. Tactile sensitivity allows the clinician to:
A. Detect changes in the tooth surface
B. Eliminate all calculus without movement
C. Determine blood pressure
D. Sterilize instruments manually
Answer: A. Detect changes in the tooth surface
Rationale: Tactile sensitivity helps the clinician detect calculus,
root irregularities, and surface changes.
Hygienist Chapter 37 (Modules 3–8) | 150
Practice Questions & Answers with Rationales
MODULE 3 — INSTRUMENT DESIGN & BASIC
INSTRUMENTATION PRINCIPLES
Questions 1–25
1. Which component of a hand instrument is primarily grasped
by the clinician?
A. Shank
B. Working end
C. Handle
D. Terminal shank
Answer: C. Handle
Rationale: The handle is the portion of the instrument designed to
be held by the clinician and provides control during
instrumentation.
2. The working end of a periodontal instrument is designed
primarily to:
A. Provide a finger rest
B. Perform the intended clinical function
C. Connect the instrument to the operator's hand
D. Control the patient's head position
,Answer: B. Perform the intended clinical function
Rationale: The working end is the functional portion of the
instrument that contacts the tooth surface or periodontal tissues.
3. Which instrument component connects the handle to the
working end?
A. Shank
B. Blade
C. Toe
D. Face
Answer: A. Shank
Rationale: The shank connects the handle to the working end and
influences access and angulation.
4. Instrument balance is important because it helps the clinician:
A. Increase the weight of the instrument
B. Maintain control with minimal muscular effort
C. Eliminate the need for a fulcrum
D. Increase calculus formation
Answer: B. Maintain control with minimal muscular effort
Rationale: Properly balanced instruments improve control and
reduce unnecessary hand and wrist strain.
,5. An instrument with a lightweight handle is generally intended
to:
A. Increase fatigue
B. Reduce tactile sensitivity
C. Improve comfort and control
D. Prevent adaptation
Answer: C. Improve comfort and control
Rationale: Lightweight ergonomic handles can decrease muscle
strain while maintaining effective tactile control.
6. The terminal shank is particularly important because it helps
the clinician determine:
A. Patient blood pressure
B. Working-end orientation
C. Tooth color
D. Instrument sterilization temperature
Answer: B. Working-end orientation
Rationale: The terminal shank provides an important visual and
tactile reference for positioning the working end.
7. A rigid instrument shank is particularly useful when:
A. Heavy calculus must be removed
B. Only polishing is being performed
C. No tactile sensitivity is required
D. The instrument is being sharpened
, Answer: A. Heavy calculus must be removed
Rationale: Greater rigidity can provide the lateral pressure
necessary for removing tenacious deposits.
8. A more flexible shank is generally advantageous when working
on:
A. Heavy supragingival calculus only
B. Delicate root surfaces
C. The instrument handle
D. The patient's cheek
Answer: B. Delicate root surfaces
Rationale: Flexible instruments can provide better adaptation
and tactile sensitivity in areas where excessive force should be
avoided.
9. Tactile sensitivity allows the clinician to:
A. Detect changes in the tooth surface
B. Eliminate all calculus without movement
C. Determine blood pressure
D. Sterilize instruments manually
Answer: A. Detect changes in the tooth surface
Rationale: Tactile sensitivity helps the clinician detect calculus,
root irregularities, and surface changes.
