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NEETMDS- Conservative Dentistry mcq
MDS PREP

Annealing of gold foil is the process by which 
 1. Contaminants are removed from the surface
 2. Rigidity decreases and ductility increases
 3. Both ductility and propotional limit decrease
 4. None of the above
Conservative Dentistry Answer: 1

Annealing gold foil is the process of heating gold to remove impurities and restore its cohesion properties. Annealing of gold foil is a heat treatment process used to alter the physical and sometimes chemical properties of the material. The primary purpose of annealing gold foil is to remove any contaminants and stresses that may be present on the surface of the material. This is achieved by heating the gold foil to a specific temperature, typically around 400°C (750°F), and then allowing it to cool slowly. The process can also help in improving the foil's ductility, making it more malleable and easier to work with. However, the direct effect of annealing on the rigidity, ductility, and proportional limit is not explicitly stated in the question, and thus the correct answer is that annealing of gold foil primarily serves to remove contaminants from the surface.


Axial wall in class V cavity in transverse section appears 
 1. Convex mediodistally and uniformaly placed in the dentin
 2. Straight with flat wall
 3. Kidney shaped with converging mesial and distal
 4. Concave shaped
Conservative Dentistry Answer: 1

The axial wall in class V cavity in transverse section appears convex
mediodistally and uniformly placed in the dentin. This is because the cavity is
typically shallower in the center and deeper towards the line angles, providing
a good seal and preventing food and plaque accumulation. 

OVERTRITURATION of silver alloy and mercury:


1) reduces contraction
2) increases strength of lathe cut alloy but reduces strength of spherical

3) decreases creep
4) gives a dull crumby mix

Conservative Dentistry Answer: 2

overtrituration (i.e., triturating for longer than the recommended time) results in a mix that is warm and has a dull surface; often the mix sticks to the capsule; it shortens setting time (because the amalgam mass becomes heated), increases contraction, and increases creep; also increases tensile and compressive strength values (for lathe-cut alloys), decreases tensile and compressive strengths (for spherical alloys); overtrituration by 10% is acceptable


By doubling the diameter of the condenser point and doubling the force applied, the operator is..............during condensation 
 1. Applying more pressure
 2. Applying less pressure
 3. Applying the same pressure
 4. Pressure applied is variable
Conservative Dentistry Answer: 2

By doubling the diameter of the condenser point and doubling the force applied,
the operator is actually applying less pressure during condensation. This is
because pressure is inversely proportional to the area of contact, which is
reduced by doubling the diameter of the condenser point. The increased force is
counteracted by the larger area of contact, resulting in a lower pressure per
unit area.


The CAD-CAM system uses
1) Cadmium in castings
2) A purcelain furnace with very high temperature
3) A video camera to all the prepared tooth
4) None of the above
Conservative Dentistry Answer: 3

The CAD-CAM system utilizes digital imaging, often through a video camera or
scanner, to capture the prepared tooth for designing restorations.


The final polish of a cat gold alloy to achieve a smooth polished surface is done by
1) Pickling
2) Electropolishing
3) Sandblasting
4) Rouge
Conservative Dentistry Answer: 4

The final polish of a cast gold alloy to achieve a smooth polished surface is
done by

1) Pickling: This is a process used to remove oxides and impurities from the
surface of a metal before applying a final finish. However, it does not provide
the final polish.
2) Electropolishing: This technique uses an electrical current to dissolve the
metal surface and create a smooth finish, but it is not commonly used for gold
alloy restorations.
3) Sandblasting: This method involves propelling an abrasive material against
the metal surface to smooth and clean it, but it is too aggressive for the final
polish of a gold alloy restoration.
4) Rouge: Rouge is a fine abrasive paste used with a polishing wheel or point to
achieve the final polish on a cast gold alloy restoration. It removes minor
imperfections and gives a high luster to the metal.

The correct answer is 4) Rouge, as it is the standard technique for achieving a
smooth, polished surface on cast gold alloys.


Which of the following restorative materials is likely to be eliminated in near future
1) Amalgams
2) Glass ionomer
3) Porcelain
4) Composites
Conservative Dentistry Answer: 1

Dental amalgam has been a traditional restorative material for many years, known for its durability and strength. However, there is a growing trend towards the use of more aesthetic materials, such as composites and glass ionomers, which blend better with natural tooth structure.


Good supplement to radiographs in diagnosing class III caries clinically is
1) Caries activity tests
2) Examine colour changes below marginal ridges
3) Mirror and explorer
4) Vitality tests
Conservative Dentistry Answer: 2

To diagnose class III caries clinically, which is caries that involves the proximal surfaces of teeth, a good supplement to radiographs is to examine the proximal surfaces for any color changes, particularly at the contact points where two teeth touch. This is often done using a combination of visual inspection and the use of a dental explorer to detect cavities and softened enamel. However, the answer provided, "Caries activity tests," refers to methods used to assess the activity or inactivity of a caries lesion, not necessarily for diagnosis.

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