MDS PREP
The opacity in ceramics is achieved by adding
1) Boric oxide
2) Copper oxide
3) Silica
4) Titanium oxide
The point at which a stress of a material exhibits a specific limited deviation P Is called
1) Proportional limit
2) Tensile strength
3) Ultimate strength
4) Yield strength
Dental Materials Answer: 4
Yield strength is the stress required to produce plastic deformation.
What is the gelation temperature range of a reversible hydrocolloid?
1) 37°C - 50°C
2) 50°C - 70°C
3) 70°C - 100°C
4) 100°C - 120°C
The gelation temperature is the point at which the material transforms from a sol to a gel, which is critical for impression making.
What is the ANSI/ADA Specification No. 96 (ISO 9917) minimum compressive strength for luting cement?
1) 50 MPa
2) 70 MPa
3) 100 MPa
4) 150 MPa
The ANSI/ADA Specification No. 96 (ISO 9917) stipulates a minimum 24-hour compressive strength of 70 MPa for standard luting consistency dental cement.
What is the ideal consistency of a luting agent according to ANSI/ADA Specification No. 96 (ISO 9917)?
1) Thixotropic
2) Plastic
3) Thin film
4) Putty
The ideal luting agent consistency is not explicitly mentioned in the text, but it should be able to flow into a film less than 25 µm thick without fragmentation.
What is the typical pH of a resin cement immediately after mixing?
1) Less than 2
2) Between 2 and 4
3) Between 4 and 7
4) Greater than 7
The pH of resin cements is usually slightly acidic after mixing, subject to variation in formulation.
What is the main component of zinc oxide-eugenol cement?
1) Zinc oxide
2) Silica
3) Phosphoric acid
4) Polycarboxylate acid
Zinc oxide-eugenol cement is primarily composed of zinc oxide and eugenol.
What are the main properties of Compomers?
1) High elasticity and high load deflection rate.
2) High modulus of elasticity and low shrinkage.
3) Easy to inject, shape, and polish with good aesthetics.
4) High thermal conductivity and good radiopacity.
Compomers are known for their ease of use, being non-sticky, and simple to place and shape. They are a hybrid of glass ionomer and composite resin properties, offering good aesthetics and user-friendly handling.