Psammoma bodies are associated with:

 # Psammoma bodies are associated with:

 A. Metastatic calcification

B. Dystrophic calcification

C. Apoptosis

D. Necrosis

The correct answer is B. Dystrophic calcification.

Psammoma bodies are round microscopic calcific collections. It is a form of dystrophic calcification. They are the characteristic feature of papillary carcinomas. 

A young adult shows non fluctuant, tender and red swelling in the marginal gingival lesion. This is most likely to be a:

 # A young adult shows non fluctuant, tender and red swelling in the marginal gingival lesion. This is most likely to be a:

 A. Periodontal abscess

B. Periapical abscess

C. Gingival abscess

D. Periapical sinus

The correct answer is C. Gingival abscess.

Gingival abscess

■ Localized, painful rapidly expanding lesion of sudden onset. 

■ It is limited to marginal gingival or interdental papilla. 

■ It is due to foreign substances carried deep into the tissues such as a toothbrush bristle, a piece of apple core, or a lobster shell. 

■ Gingival abscess involves marginal and interdental gingiva, whereas periodontal abscess involves attached gingiva. 

Palmar and plantar hyperkeratosis is a feature of:

 # Palmar and plantar hyperkeratosis is a feature of:

 A. Down syndrome

B. Papillon Lefevre Syndrome

C. Chediak-Higashi Syndrome

D. Klinefelter syndrome

The correct answer is B. Papillon Lefevre Syndrome.

Papillon-Lefevre Syndrome 

1. This is characterized by hyperkeratotic skin lesions and severe destruction of the periodontium. 

2. These changes may appear before the age of 4 years. 

3. Skin lesions are—hyperkeratosis of localized areas on palms, soles, knees, and elbows. 

4. Periodontal involvement is early inflammatory changes that lead to bone loss and exfoliation of teeth. Primary teeth are lost by 5 or 6 years of age. The permanent dentition erupts normally but the permanent teeth are lost within a few years. 

Ions participating in clotting mechanism are:

 # Ions participating in clotting mechanism are:

 A. Iron

B. Copper

C. Calcium

D. Aluminium

The correct answer is C. Calcium.

In the presence of calcium ions and other clotting factors, factor X activates an enzyme called prothrombin activator. This enzyme then converts the plasma protein prothrombin into thrombin. Thrombin is an enzyme that, in turn, converts fibrinogen to fibrin which causes the blood to clot.

Side effects of Phenytoin do not include:

 # Side effects of Phenytoin do not include:

 A. Osteomalacia

B. Gum hypertrophy

C. Folate deficiency

D. Blindness

The correct answer is D. Blindness. 

Adverse effects:  After prolonged use numerous side effects are produced at therapeutic plasma concentration; others occur as a manifestation of toxicity due to overdose.

At therapeutic levels

• Gum hypertrophy is common (20% incidence), especially in younger patients. It is due to the overgrowth of gingival collagen fibers. This can be minimized by maintaining oral hygiene.

• Hirsutism, coarsening of facial features (troublesome in young girls), acne.

• Hypersensitivity reactions are—rashes, DLE, and lymphadenopathy; neutropenia is rare but requires discontinuation of therapy.

• Megaloblastic anemia: Phenytoin decreases folate absorption and increases its excretion.

• Osteomalacia: Phenytoin interferes with metabolic activation of vit D and with calcium

absorption/metabolism.

• It can inhibit insulin release and cause hyperglycemia.

• Used during pregnancy, phenytoin can produce ‘fetal hydantoin syndrome’ (hypoplastic phalanges, cleft palate, hare lip, microcephaly), which is probably caused by its areneoxide metabolite.

Reference: Essentials of medical pharmacology, KD Tripathi.

At what temperature is blood stored in blood banks?

 # At what temperature is blood stored?

 A. -4 degrees

B. 4 degrees

C. 6 degrees

D. 8 degrees

The correct answer is B. 4 degrees celsius.

With the modern surgical and medical procedures, the demand for blood has greatly increased. It is for this reason that blood banks were started where blood from voluntary donors could be stored, so that it was always available on demand. Most blood banks have lists of would-be donors so that they may be contacted when required.

Storage of blood: After a donor has been screened for donation, one unit of blood (450 ml) is collected, under aseptic conditions, from the antecubital vein directly into a special plastic bag containing 63 ml of CPD-A (citrate-phosphate-dextrose-adenine) mixture. The blood bag is suitably sealed, labeled, and stored at 4 degree C, where it can be kept for about 20 days. (Faulty storage, i.e. overheating or freezing can lead to gross infection and hemolysis). The citrate prevents clotting of blood, sodium diphosphate acts as a buffer to control decrease in pH, dextrose supports ATP generation via glycolytic pathway and also provides energy for Na+- K+ pump that maintains the size and shape of red cells and increases their survival time, and adenine provides substrate for the synthesis of ATP, thus improving post-donation viability of red cells.

Blood is stored at low temperatures for 2 reasons: one, it decreases bacterial growth, and two, it decreases the rate of glycolysis and thus prevents a quick fall in pH.

Reference: A TEXTBOOK OF PRACTICAL PHYSIOLOGY Eighth Edition CL Ghai

Which mandibular plane is considered while calculating FMA (Frankfort mandibular plane angle) in cephalometry?

The mandibular plane used for FMA measurement is : A plane tangent to the lower border of mandible which connects with the menton anteriorly and posteriorly it bisects the distance between the right and left lower borders of the mandible in the region of the gonial angle. See Figure. 

The FMA angle is defined as the angle formed by the following two reference planes:

i. FH plane (Frankfort horizontal plane—A line between the most superior point of the external auditory meatus and inferior border of the orbit).

ii. Mandibular plane (A plane tangent to the lower border of mandible which connects with the menton anteriorly and posteriorly it bisects the distance between the right and left lower borders of the mandible in the region of the gonial angle). 

In most cephalometric analyses, the occlusal and mandibular planes are measured relative to the sella-nasion (SN) line, the basion-nasion (BaN) line, or the Frankfort horizontal plane. Ideally, according to Tweed, the incisor mandibular plane angle (IMPA) should be 90 degrees, the Frankfort mandibular angle (FMA) 25 degrees, and thus the Frankfort mandibular incisor angle (FMIA) 65 degrees. (The sum of three angles of a triangle equals 180 degrees.) Moreover, the IMPA angle also relates to creating additional space in the mandibular arch in that for each 3 degrees advancement of the lower incisor, 2.5 mm of space is gained in the mandibular dental arch. Conversely, reduction of the IMPA from 90 degrees, for example, to 87 degrees would decrease the available space for tooth alignment in the mandibular dental arch by 2.5 mm.