NEET MDS Shorts
30407
Dental Materials
Heating a gypsum cast to a temperature above 90°C will remove water of
crystallization and strengthen it. This process is called "burning out" the
gypsum, and it is used to remove the remaining moisture and improve the cast's
stability and accuracy. Gypsum casts are made by mixing plaster of Paris (calcium sulfate hemihydrate)
with water. When the material sets, it forms calcium sulfate dihydrate crystals
with water molecules trapped within the crystal lattice, known as water of
crystallization. Heating the cast above 90°C causes the water of crystallization
to be released, which results in the cast becoming stronger and more rigid. This
process does not cause the cast to expand but rather to shrink slightly as the
water is removed. Excess gauging water is typically removed during the initial
setting process.
94639
INI CET
The lesser wing of sphenoid is considered part of horizontal trajectories rather than vertical trajectories.
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INI CET
A Stacked bar graph is used to show how a larger category is divided into smaller sub-categories and the relationship of each part to the whole.
26058
NEETMDSAnterior crossbite in a 10-year-old child, particularly if functional, can sometimes be a self-correcting anomaly, especially if the underlying cause (e.g., premature contact) is addressed or with natural growth changes. Other conditions like buccoversion of the mandibular first molar, anterior open bite, and flaring of incisors typically require intervention to correct.
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Conservative DentistryProximal carious lesions often appear smaller on radiographs than they are clinically due to the limitations of radiographic imaging.
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Oral PathologyDry socket, also known as alveolar osteitis, is a painful condition that occurs after a tooth extraction when the blood clot fails to form or is dislodged before the wound has a chance to heal. It is an inflammation of the bone (osteitis) in the tooth socket, specifically the alveolar bone, but does not involve an infection of the bone marrow, which would be osteomyelitis.
48666
PhysiologyCalbindin binds calcium and prevents it from affecting epithelial signaling, facilitating calcium absorption in the intestine.
88797
Oral PathologyVitamin A deficiency is associated with hyperplasia and keratinization of the salivary glands.
24956
OrthodonticsThe high labial-bow is typically used for molar retraction and is not designed for incisor retraction. In contrast, Roberts retractors, split labial-bows, and apron springs are all instruments that can be used effectively for retracting incisors during orthodontic treatment.
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Conservative Dentistry
Explanation: In Class III composite preparations, retention
points should be placed entirely in dentin. This is because dentin provides a
more reliable substrate for bonding compared to enamel, especially in areas
where the enamel may be thin or compromised. By placing retention points in
dentin, the restoration can achieve better mechanical retention and bonding
strength, which is crucial for the longevity of the restoration.