MDS PREP
When preparing adjacent class III cavities recommended procedures
1. Prepare large first but fill last
2. Prepare small first but fill last
3. Prepare and fill the small first
4. Prepare and fill the large first
Explanation: When dealing with adjacent Class III cavities, it is generally recommended to prepare the larger cavity first and fill it last. This approach allows the dentist to have better access and visibility when preparing the larger cavity, which can be more complex. Filling the larger cavity last helps to avoid contamination and ensures that the smaller cavity can be filled with precision without compromising the integrity of the larger restoration.
Gingivally the depth of a class V cavity is
1. 0.5-1 mm
2. 0.75-1 mm
3. 1-1.25 mm
4. 2-3 mm
Conservative Dentistry
Answer: 2
Gingivally, the depth of a class V cavity is typically 0.75-1 mm. This depth is
sufficient to provide a good bond with the tooth structure and prevent
microleakage without causing significant gingival irritation or damage.
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
The advantage of natural glaze compared to applied artificial glaze
1) More smooth finish is achieved
2) More permanent glaze is achieved
3) More shiny surface is achieved
4) All of the above
Conservative Dentistry
Answer: 2
Natural glaze is often more durable and permanent compared to applied artificial
glaze, providing a better finish.
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.
The base of class III preparation is
1) Axial wall
2) Gingival wall
3) Facial wall
4) Lingual wall
Conservative Dentistry
Answer: 1
In a Class III cavity preparation, which typically involves the anterior teeth and is located on the proximal surfaces, the axial wall is considered the base. This wall is oriented parallel to the long axis of the tooth and provides support for the restoration. The gingival wall is also important, but the axial wall is the primary base in this context.
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.