ORE Part 2 Clinical Skills Assessment — Questions and Answers
Question 1: During a clinical skills assessment, a patient presents with a fractured upper central incisor involving enamel and dentine but with no pulp exposure. What is the most appropriate immediate management?
- Extract the tooth and plan a bridge
- Place a calcium hydroxide liner and restore with composite resin (Correct answer)
- Perform elective root canal treatment before restoration
- Place a stainless steel crown
Correct answer: Place a calcium hydroxide liner and restore with composite resin
For an uncomplicated crown fracture involving enamel and dentine without pulp exposure, the correct management is to place a calcium hydroxide liner over the exposed dentine to promote reparative dentine formation, followed by a definitive composite restoration to seal the tooth and restore aesthetics and function.
Question 2: When taking a dental impression for a crown, which impression material provides the best dimensional accuracy?
- Alginate (irreversible hydrocolloid)
- Addition-cured silicone (polyvinyl siloxane) (Correct answer)
- Zinc oxide eugenol impression paste
- Compound impression material
Correct answer: Addition-cured silicone (polyvinyl siloxane)
Addition-cured silicone (polyvinyl siloxane/PVS) provides the highest dimensional accuracy and stability among impression materials. It has excellent elastic recovery, very low shrinkage, and can be poured at a later time without significant dimensional change, making it the material of choice for crown and bridge impressions.
Question 3: A patient requires a Class II composite restoration on the mesial surface of an upper premolar. What is the purpose of using a sectional matrix band?
- To isolate the tooth from saliva
- To create a tight proximal contact and natural tooth contour (Correct answer)
- To prevent the composite from bonding to enamel
- To hold the rubber dam in place
Correct answer: To create a tight proximal contact and natural tooth contour
A sectional matrix band, used with a separation ring, helps create a tight proximal contact point and natural anatomical contour of the restoration. The ring provides separation force between the teeth, compensating for the slight over-contouring needed, and the curved matrix recreates the natural proximal surface shape.
Question 4: What is the correct sequence for applying a total-etch bonding system to a cavity preparation?
- Prime, etch, bond, cure
- Etch, rinse, dry, apply primer and bond, cure (Correct answer)
- Bond, etch, prime, cure
- Etch, dry thoroughly, bond, cure
Correct answer: Etch, rinse, dry, apply primer and bond, cure
The total-etch (etch-and-rinse) technique involves: (1) etching enamel and dentine with 37% phosphoric acid for 15-20 seconds on enamel and 10-15 seconds on dentine, (2) rinsing thoroughly, (3) blot-drying to leave dentine slightly moist, (4) applying primer and bonding agent, (5) light-curing. Over-drying the dentine causes collagen collapse and reduced bond strength.
Question 5: During a clinical assessment, you notice the patient's existing amalgam restoration has a marginal gap but no secondary caries. What is the evidence-based approach?
- Replace the restoration immediately with composite
- Monitor the restoration and repair if necessary (Correct answer)
- Remove all amalgam and place a crown
- Apply fissure sealant over the margin
Correct answer: Monitor the restoration and repair if necessary
Current evidence-based dentistry supports monitoring defective restorations that show marginal gaps but no evidence of secondary caries, fracture, or other failure criteria. The 'repair rather than replace' philosophy minimises unnecessary removal of tooth structure and extends the functional life of the restoration.
Question 6: Which isolation method provides the best moisture control for placing a composite restoration?
- Cotton wool rolls and saliva ejector
- Dry Guard system
- Rubber dam isolation (Correct answer)
- High-volume suction only
Correct answer: Rubber dam isolation
Rubber dam provides the gold standard for moisture control during adhesive restorative procedures. It completely isolates the operating field from saliva and gingival crevicular fluid, prevents aspiration of small instruments, improves visibility, and ensures the dry field essential for optimal bonding of composite resins.
ORE Part 2 Clinical Skills Assessment
During a clinical skills assessment, a patient presents with a fractured upper central incisor involving enamel and dentine but with no pulp exposure.
What is the most appropriate immediate management?