Dental Materials MCQs
Dental Materials MCQs test the understanding of restorative and preventive materials used in dentistry. Topics include dental amalgam, composite resins, glass ionomers, impression materials, and adhesives. These MCQs are valuable for BDS and MDCAT students aiming to grasp the properties, manipulation, and clinical use of dental materials.
Q: Color matching in restorations is influenced by
A) Opacity
B) Hue, value, and chroma
C) Radiopacity
D) Density
✅ Correct Answer: B
Explanation: The key factors are hue, value, and chroma in color perception.
Q: Initial setting time of GIC can be affected by
A) Pressure
B) Etching
C) Light curing
D) Humidity
✅ Correct Answer: D
Explanation: GIC setting is sensitive to ambient humidity.
Q: Tensile failure in brittle materials is due to
A) Temperature
B) Moisture
C) Micro-cracks
D) Plasticity
✅ Correct Answer: C
Explanation: Brittle materials fail under tension due to propagation of micro-cracks.
Q: The most moisture-sensitive impression material is
A) Polyether
B) Silicone
C) Polysulfide
D) Alginate
✅ Correct Answer: A
Explanation: Polyether is hydrophilic but highly sensitive to ambient moisture.
Q: Coefficient of thermal expansion is highest in
A) Enamel
B) Amalgam
C) Porcelain
D) Composite resin
✅ Correct Answer: D
Explanation: Composites expand more with heat compared to natural tooth tissues.
Q: Delayed expansion in zinc-containing amalgam is caused by
A) Lack of pressure
B) Over-trituration
C) Excess mercury
D) Moisture contamination
✅ Correct Answer: D
Explanation: Moisture contamination causes hydrogen gas formation, leading to delayed expansion.
Q: Cohesive failure occurs within the
A) Adhesive
B) Substrate
C) Interface
D) Material itself
✅ Correct Answer: D
Explanation: Cohesive failure happens when the fracture is inside the adhesive or restorative material.
Q: High copper amalgams exhibit
A) Low strength
B) High creep
C) Corrosion
D) No gamma-2 phase
✅ Correct Answer: D
Explanation: High copper amalgams eliminate the weak gamma-2 phase for improved properties.
Q: Polymerization shrinkage is lowest in
A) Microfill composite
B) Hybrid composite
C) Bulk-fill composite
D) Flowable composite
✅ Correct Answer: C
Explanation: Bulk-fill composites are engineered to reduce polymerization shrinkage.
Q: Glass ionomer cements are primarily bonded to tooth structure by
A) Mechanical retention
B) Ionic interaction
C) Resin tags
D) Chelation with collagen
✅ Correct Answer: B
Explanation: Ionic bonds form between glass ionomer and calcium in the tooth.