DENTAL MATERIALS EXAM 2 | DENTAL
HYGIENIST| DENTAL HYGIENIST | LATEST
2025-2026 QUESTION AND CORRECT ANSWER
WITH EXPLANATION WEST COAST
UNIVERSITY
1. Question
A composite restoration fails prematurely due to marginal breakdown.
What is the MOST likely contributing factor?
A. High fluoride release
B. Polymerization shrinkage stress
C. Excess enamel thickness
D. Low saliva pH
Correct Answer: B
Rationale: Shrinkage stress creates marginal gaps leading to failure.
2. Question
Which bonding condition MOST improves adhesion to dentin?
A. Wet, contaminated surface
B. Moist, properly conditioned dentin with adhesive application
C. Thick smear layer intact
D. Delayed curing
Correct Answer: B
Rationale: Proper moisture control allows hybrid layer formation.
3. Question
What is the PRIMARY purpose of acid etching enamel?
A. Increase tooth hardness
B. Create microporosities for micromechanical retention
C. Reduce sensitivity
D. Increase fluoride uptake
,Correct Answer: B
Rationale: Etching produces a rough surface for bonding.
4. Question
A patient experiences postoperative sensitivity after composite placement.
What is the MOST likely cause?
A. Excess fluoride
B. Microleakage at margins
C. Over-polishing
D. High enamel density
Correct Answer: B
Rationale: Microleakage allows fluid movement stimulating dentin.
5. Question
Which property defines resistance to permanent deformation?
A. Elasticity
B. Strength
C. Solubility
D. Color stability
Correct Answer: B
Rationale: Strength is resistance to failure under stress.
6. Question
Which material is MOST likely to undergo corrosion in oral fluids?
A. Gold alloy
B. Amalgam
C. Ceramic
D. Porcelain
Correct Answer: B
Rationale: Amalgam can undergo electrochemical corrosion.
, 7. Question
What is the MAIN disadvantage of glass ionomer cement?
A. Fluoride release
B. Low fracture toughness
C. High adhesion
D. Aesthetic stability
Correct Answer: B
Rationale: Glass ionomers are brittle.
8. Question
Which property describes resistance to wear?
A. Abrasion resistance
B. Elasticity
C. Creep
D. Viscosity
Correct Answer: A
Rationale: Abrasion resistance prevents material loss.
9. Question
What is the PRIMARY cause of composite discoloration?
A. Fluoride uptake
B. Water absorption and staining
C. Increased hardness
D. Enamel thickness
Correct Answer: B
Rationale: Resin absorbs pigments and fluids over time.
10. Question
HYGIENIST| DENTAL HYGIENIST | LATEST
2025-2026 QUESTION AND CORRECT ANSWER
WITH EXPLANATION WEST COAST
UNIVERSITY
1. Question
A composite restoration fails prematurely due to marginal breakdown.
What is the MOST likely contributing factor?
A. High fluoride release
B. Polymerization shrinkage stress
C. Excess enamel thickness
D. Low saliva pH
Correct Answer: B
Rationale: Shrinkage stress creates marginal gaps leading to failure.
2. Question
Which bonding condition MOST improves adhesion to dentin?
A. Wet, contaminated surface
B. Moist, properly conditioned dentin with adhesive application
C. Thick smear layer intact
D. Delayed curing
Correct Answer: B
Rationale: Proper moisture control allows hybrid layer formation.
3. Question
What is the PRIMARY purpose of acid etching enamel?
A. Increase tooth hardness
B. Create microporosities for micromechanical retention
C. Reduce sensitivity
D. Increase fluoride uptake
,Correct Answer: B
Rationale: Etching produces a rough surface for bonding.
4. Question
A patient experiences postoperative sensitivity after composite placement.
What is the MOST likely cause?
A. Excess fluoride
B. Microleakage at margins
C. Over-polishing
D. High enamel density
Correct Answer: B
Rationale: Microleakage allows fluid movement stimulating dentin.
5. Question
Which property defines resistance to permanent deformation?
A. Elasticity
B. Strength
C. Solubility
D. Color stability
Correct Answer: B
Rationale: Strength is resistance to failure under stress.
6. Question
Which material is MOST likely to undergo corrosion in oral fluids?
A. Gold alloy
B. Amalgam
C. Ceramic
D. Porcelain
Correct Answer: B
Rationale: Amalgam can undergo electrochemical corrosion.
, 7. Question
What is the MAIN disadvantage of glass ionomer cement?
A. Fluoride release
B. Low fracture toughness
C. High adhesion
D. Aesthetic stability
Correct Answer: B
Rationale: Glass ionomers are brittle.
8. Question
Which property describes resistance to wear?
A. Abrasion resistance
B. Elasticity
C. Creep
D. Viscosity
Correct Answer: A
Rationale: Abrasion resistance prevents material loss.
9. Question
What is the PRIMARY cause of composite discoloration?
A. Fluoride uptake
B. Water absorption and staining
C. Increased hardness
D. Enamel thickness
Correct Answer: B
Rationale: Resin absorbs pigments and fluids over time.
10. Question
