Bases, Liners, and Sealants Flashcards
7 cards from real EFDA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Bases, Liners, and Sealants flashcards as text
Before placing a resin-based pit and fissure sealant, the tooth surface is conditioned with:
Answer: Phosphoric acid etchant
Phosphoric acid (usually 35–37%) etches enamel to create microporosities for micro-mechanical retention of the sealant.
A glass ionomer base is described as being 'biocompatible' primarily because:
Answer: Its final pH is close to neutral and it chemically bonds to tooth structure
Glass ionomer's final pH approaches neutral and its chemical adhesion to hydroxyapatite makes it well-tolerated by pulpal tissue.
Which sealant type does NOT require a separate curing light and polymerizes through a chemical reaction when two components are mixed?
Answer: Autopolymerizing (self-cured) sealant
Autopolymerizing sealants undergo chemical polymerization when base and catalyst are mixed, without requiring a curing light.
When evaluating a placed sealant, an EFDA uses an explorer to check for:
Answer: Tactile retention and absence of voids or lifted margins
An explorer is used to confirm that the sealant is firmly retained and that there are no voids, bubbles, or lifted edges that could allow leakage.
In a very deep preparation approaching the pulp, the FIRST material placed is typically:
Answer: A layer of calcium hydroxide over the deepest point
Calcium hydroxide is placed first over the deepest area closest to the pulp to stimulate secondary dentin and protect pulpal tissue.
Which property of calcium hydroxide makes it effective for indirect pulp capping?
Answer: Its alkalinity stimulates the formation of reparative dentin
Calcium hydroxide's high pH (around 11–12) causes mild pulp irritation that stimulates odontoblasts to produce reparative (tertiary) dentin.
Placing a sealant on a tooth that already has an incipient interproximal lesion visible radiographically is considered:
Answer: A contraindication because the sealant cannot access interproximal surfaces
Pit and fissure sealants are placed on occlusal surfaces and cannot treat or adequately seal interproximal lesions, which are a contraindication.