Prosthodontics and Operative Dentistry Flashcards
7 cards from real NBDE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Prosthodontics and Operative Dentistry flashcards as text
The 'ferrule effect' in crown preparation refers to:
Answer: The extension of the crown margin 1.5-2 mm onto sound tooth structure above the finish line
The ferrule effect is a 360° band of tooth structure at least 1.5-2 mm above the CEJ or finish line, which dramatically increases resistance to fracture.
Which type of impression technique is most appropriate for a distal extension removable partial denture?
Answer: Functional (selective pressure) impression
A functional impression records the distal extension tissue under simulated functional load, ensuring the denture base is supported under pressure.
Glass ionomer cement is uniquely beneficial as a base or liner because it:
Answer: Bonds chemically to tooth structure and releases fluoride
Glass ionomer forms a chemical bond with both enamel and dentin and releases fluoride ions, providing both adhesion and cariostatic benefits.
When surveying a cast for a removable partial denture, tilting the cast anteriorly will:
Answer: Increase undercuts on the anterior teeth and decrease them on posterior teeth
Tilting the cast anteriorly changes the path of insertion, increasing mesial undercuts and decreasing distal undercuts on posterior abutments.
The term 'centric relation' in prosthodontics refers to:
Answer: The most retruded, superior position of the condyles in the glenoid fossae
Centric relation is a jaw position (not tooth position) defined as the most superior, anterior position of the condyles in the glenoid fossae, reproducible and joint-based.
The primary purpose of a rubber dam during operative procedures is to:
Answer: Maintain a dry, contamination-free field for bonding procedures
The rubber dam isolates the operating field from saliva and crevicular fluid, which is essential for achieving optimal bonding of adhesive restorations.
A patient presents with a fractured cusp on a maxillary molar. The fracture extends 2 mm below the gingival margin but remains supracrestal. The best restorative option is:
Answer: Crown lengthening followed by full coverage crown
Crown lengthening establishes biologic width clearance below the new finish line, after which a full coverage crown provides necessary cuspal protection.