Dental Materials and Application Flashcards
7 cards from real AGD practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Dental Materials and Application flashcards as text
What is the primary clinical advantage of self-adhesive resin cements (e.g., RelyX Unicem) over conventional resin cements?
Answer: They eliminate the need for separate etching and priming steps
Self-adhesive resin cements contain acidic monomers that simultaneously etch, prime, and bond to tooth structure in a single step, simplifying the luting procedure.
During amalgam condensation, why is it important to use small-diameter condensers and apply firm pressure?
Answer: To adapt the material to cavity walls and eliminate voids
Small condensers with firm pressure adapt amalgam to all cavity walls, eliminate internal voids that weaken the restoration, and ensure intimate contact with the preparation.
A patient receives a new ceramic crown that feels high in occlusion. The dentist adjusts it intraorally with a diamond bur. What must be done next?
Answer: Repolish with diamond polishing paste and a felt disk
Intraoral adjustment with a diamond bur destroys the glaze and creates surface roughness; repolishing with diamond paste restores smoothness and reduces wear of opposing teeth.
The Shore A hardness scale is most commonly used to measure the hardness of:
Answer: Dental elastomers and soft denture liners
Shore A hardness measures the hardness of soft, rubbery materials including elastomeric impression materials, soft denture liners, and occlusal splints.
Which property differentiates addition silicone (VPS) from condensation silicone impression materials?
Answer: Addition silicone has no byproduct and exhibits superior dimensional stability
Addition silicone cross-links without releasing byproducts, resulting in virtually zero dimensional change, which is why it is the gold standard for precision impressions.
Which base material placed under a deep restoration primarily serves to stimulate reparative dentin formation?
Answer: Calcium hydroxide
Calcium hydroxide (Ca(OH)2) has a high pH (~12) that stimulates odontoblasts or undifferentiated cells to form reparative (tertiary) dentin when placed near the pulp.
What is the main reason for using a rubber dam during composite resin placement?
Answer: To prevent moisture contamination that inhibits adhesive bonding
Saliva and crevicular fluid contaminate the bonded surfaces, disrupting the hybrid layer and dramatically reducing composite resin bond strength.