MDS PREP
What is the primary advantage of resin teeth over porcelain teeth in terms of impact resistance and ductility?
1) Resin teeth are more likely to chip or fracture.
2) Resin teeth have better dimensional stability.
3) Resin teeth have greater wear resistance.
4) Resin teeth are less likely to chip or fracture.
Resin teeth are more ductile than porcelain teeth, which means they can absorb and distribute forces better, making them less prone to chipping or fracturing on impact.
Bonding of GIC to tooth structure is brought about by
1) metal ions
2) hydroxyl bond
3) carboxyl bond
4) ionic bond
Dental Materials Answer: 3
one ot the main adanhtges of GIC as a restoratie material was its ability to form chemical bonds with the tooth structure.
Bonding in GIC primarily invokes chelation of carboxyl groups of the polyacids sith the calcium in the apatite of enamel and dentin. Bond rength of enamel is always greater than that of dentin due to higher mineral content. The bonding is improved by the removal of the debris layer called smear layer’ by a process called conditioning.
In orthodontic wire selection, what is the benefit of using a wire with a high load deflection rate?
1) It provides a constant force over a wider range of tooth movements.
2) It is more suitable for areas requiring minimal tooth movement.
3) It is less prone to permanent deformation during activation.
4) It has a steeper force-deflection curve.
In orthodontics, wires with a high load deflection rate are beneficial in areas where minimal tooth movement is desired, such as in maximum anchorage extraction cases or during finishing.
What are the two primary components of the liquid phase of a denture base resin?
1) Nonpolymerized methyl methacrylate and a cross-linking agent
2) Prepolymerized beads and benzoyl peroxide
3) Hydroquinone and glycol dimethacrylate
4) Monomer and initiator
The liquid phase of a denture base resin primarily consists of nonpolymerized methyl methacrylate (monomer) and a cross-linking agent like glycol dimethacrylate.
Which of the following shows highest permanent deformation following strain in compression :
1) Polysulphide impression material
2) Polyether impression material
3) Condensation silicones
4) Addition silicones
Dental Materials Answer: 1
For permanent deformation following strain in compression, ranking is mentioned below:
Polysulfide > polyethers > condensation silicone > addition silicone
What is the typical setting time range for Type II (Normal set) alginate impression material?
1) 1-2 minutes
2) 2-4 minutes
3) 4-6 minutes
4) 6-8 minutes
Type II (Normal set) alginate impression material has a setting time of 2-4 minutes, which is longer than the fast-setting Type I material.
What is the difference between type I and type II glass ionomer cements?
1) Type I has a higher fluoride release
2) Type II has a higher compressive strength
3) Type I sets faster
4) Type II has better aesthetic properties
Type II glass ionomer cements have a higher compressive strength, while Type I is often used for better aesthetics.
What is the main advantage of using Ormocers in dental restorations?
1) They have a high coefficient of thermal expansion.
2) They have excellent biocompatibility and resistance to masticatory loading.
3) They are easy to manipulate and require minimal finishing.
4) They can be used in high-stress bearing areas without reinforcement.
The main advantage of using Ormocers is their excellent biocompatibility and resistance to masticatory loading. They also have good esthetic properties, resembling those of natural teeth.