MDS PREP
In class V preparation the wall which is not present at all
1. Pulpal
2. Distal
3. Mesial
4. Axial
Conservative Dentistry
Answer: 1
In class V preparation, the pulpal wall is not present at all, as the cavity is
confined to the cervical third of the tooth. It does not extend into the pulp
chamber.
Upper limit of urinary mercury attributed to extensive amalgam restoration
1) 1 microgram/g of creatinine
2) 3 microgram/g of creatinine
3) 2 microgram/g of creatinine
4) 4 microgram/g of creatinine
Conservative Dentistry
Answer: 4
The upper limit of urinary mercury attributed to extensive amalgam restoration is typically considered to be 4 micrograms/g of creatinine. While the actual limit can vary based on the individual and the extent of amalgam fillings, a level of 4 micrograms/g of creatinine is commonly used as a benchmark for evaluating potential health concerns related to mercury exposure from dental amalgam.
Aluminium oxide polishing powder is obtained from
1) Aluminium
2) Cryolite
3) Bauxite
4) Vulcanite
Conservative Dentistry
Answer: 3
Aluminium oxide (Al₂O₃) is primarily derived from bauxite, which is an ore that contains a high percentage of aluminium. The Bayer process is commonly used to extract aluminium oxide from bauxite.
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.
Pit and fissure caries can be best pre vented by
1. the use of adhesive sealants
2. topical fluoride application
3. diet control
4. effective plaque control
Conservative Dentistry Answer: 1
1. The use of adhesive sealants: Adhesive sealants are thin, plastic coatings
applied to the chewing surfaces of the back teeth. They fill in the grooves and
depressions, creating a smooth surface that is easier to clean. Sealants act as
a barrier, preventing food and bacteria from lodging in these areas and thus
reducing the risk of tooth decay. This is considered the best preventive measure
because it directly addresses the anatomical vulnerability of the teeth and can
be applied quickly and painlessly.
2. Topical fluoride application: While topical fluoride is beneficial in
preventing dental cavities, it is not as effective as sealants in preventing pit
and fissure caries. Fluoride helps to strengthen the enamel and makes it more
resistant to acid attacks from plaque bacteria. However, because the pits and
fissures are already deep and narrow, fluoride may not always reach these areas
effectively. Sealants, on the other hand, provide a physical barrier that
fluoride cannot always penetrate.
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.
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
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
Which of the following is not recommended in the technique for curing light cured composites?
1) Holding the light tip 1 cm from the tooth
2) Wearing speacial glasses with orange filters
3) Using an exposure duration of 40 to 60 seconds
4) Placing the composite in increments of 1 to 2 mm
Conservative Dentistry Answer: 1
The distance between the tip of the curing light and the tooth is important, as the intensity of the light source is important. A minimum of 400-mW/cm2 is required. It is recommended that the tip be placed as close to the surface to be cured as is physically possible (within 1 to 2mm).
The intensity of light is inverselyproportional to the distance from the source. As a general rule each increment should be at most 1.5 to 2 mm thick. This will ensure complete penetration of the light and maximum curing of thecomposite at the bottom most portion of the cavity preparation.