Dental Materials Flashcards
6 cards from real MFDS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Dental Materials flashcards as text
Which bonding agent generation first introduced self-etching primers to eliminate the separate acid-etch step?
Answer: 6th generation
6th generation adhesives introduced self-etching primers that simultaneously condition and prime without a separate phosphoric acid etch step.
The Vickers hardness of enamel is approximately:
Answer: 343 VHN
Enamel has a Vickers hardness of approximately 343 VHN, making it the hardest biological tissue in the human body.
Which type of gypsum product has the highest compressive strength?
Answer: Die stone (Type IV)
Type IV die stone (high-strength dental stone) has the highest compressive strength due to the regular particle shape resulting from autoclaving.
What causes the 'creep' of dental amalgam restorations at amalgam margins?
Answer: Time-dependent plastic deformation under occlusal load
Creep is time-dependent plastic deformation of amalgam under sustained occlusal stress, leading to marginal overhang and ditching over time.
Which impression material is most susceptible to tearing in thin cross-sections?
Answer: Condensation silicone
Condensation silicone (C-silicone) has lower tear strength and elastic recovery compared to addition silicone (A-silicone) and is more prone to tearing in fine detail areas.
Which characteristic of zirconia makes it suitable for high-load dental restorations?
Answer: Transformation toughening
Zirconia undergoes stress-induced transformation toughening: tetragonal to monoclinic crystal phase transformation at crack tips generates compressive stresses that halt crack propagation.