ORE Part 2 Restorative Dentistry 2 — Questions and Answers
Question 1: Which type of glass ionomer cement is most appropriate as a lining under a composite restoration?
- Conventional glass ionomer (resin-modified) (Correct answer)
- Zinc phosphate cement
- Calcium hydroxide only
- Polycarboxylate cement
Correct answer: Conventional glass ionomer (resin-modified)
Resin-modified glass ionomer is ideal as a lining due to its fluoride release, adhesion to dentine, and compatibility with composite bonding systems.
Question 2: What is the purpose of a wedge when placing a Class II restoration?
- Separate the teeth and adapt the matrix band (Correct answer)
- Stabilise the matrix band against the bur
- Protect the adjacent tooth from preparation
- Prevent overhang formation at the gingival margin only
Correct answer: Separate the teeth and adapt the matrix band
A wedge separates teeth slightly to compensate for matrix thickness, adapts the band cervically, and protects the adjacent tooth during preparation.
Question 3: According to current UK guidelines, when should a direct pulp cap be considered?
- Mechanical exposure in a symptom-free tooth with healthy pulp (Correct answer)
- Carious exposure in any tooth
- Teeth with spontaneous pain
- All cases of pulp exposure
Correct answer: Mechanical exposure in a symptom-free tooth with healthy pulp
Direct pulp cap is indicated for mechanical or traumatic exposures in teeth with no signs of irreversible pulpitis, offering a chance of pulp preservation.
Question 4: Which base material provides the greatest thermal insulation under a metallic restoration?
- Zinc oxide eugenol cement (Correct answer)
- Zinc phosphate cement
- Resin-modified glass ionomer
- Calcium silicate cement
Correct answer: Zinc oxide eugenol cement
Zinc oxide eugenol has sedative properties and low thermal conductivity, making it an effective base for thermal insulation under metal restorations.
Question 5: What is the recommended occlusal reduction for a full-coverage porcelain-fused-to-metal (PFM) crown on a posterior tooth?
- 1.5–2.0 mm (Correct answer)
- 0.5–1.0 mm
- 2.5–3.0 mm
- 3.0–4.0 mm
Correct answer: 1.5–2.0 mm
A minimum of 1.5–2.0 mm occlusal reduction is required for PFM crowns to allow adequate metal and porcelain thickness without compromising strength.
Question 6: Which finishing bur is most appropriate for contouring composite resin in the interproximal area?
- Flame-shaped fine diamond or finishing strip (Correct answer)
- Round carbide bur
- Pear-shaped tungsten carbide
- Large wheel diamond
Correct answer: Flame-shaped fine diamond or finishing strip
Flame-shaped fine diamonds or abrasive finishing strips are used interproximally to contour and polish composite without damaging adjacent teeth.
ORE Part 2 Restorative Dentistry 2
Which type of glass ionomer cement is most appropriate as a lining under a composite restoration?