MDS PREP
During cavity preparation, more incidence of exposure is in
1. Class V cavity in first premolar
2. Class II mesioocclusal cavity
3. Class II distoocclusal cavity
4. Class IV cavity
Conservative Dentistry
Answer: 1
During cavity preparation, the incidence of pulpal exposure is higher in class V
cavities on first premolars due to the proximity of the margins to the pulp
horns.
How much fraction of methyl mercuryis absorbed from gut
1)20%
2)50%
3)80%
4)100%
Conservative Dentistry
Answer: 4
100% of methyl mercury is absorbed from the gut. After absorption methyl mercury binds to hemoglobin, circulates systemically and is distributed to all organs, including the brain
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.
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.
When punching holes to place a rubber dam for a class V cavity on facial surface
1. Punch holes larger and facially
2. Punch holes smaller and lingually
3. Punch holes larger and lingually
4. Punch holes smaller and facially
Conservative Dentistry
Answer: 1
When punching holes to place a rubber dam for a class V cavity on the facial
surface, punching holes larger and facially provides better access and
visibility. This allows for easier placement and removal of the dam, as well as
less risk of damaging the adjacent tissue
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.
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