MDS PREP
Radiation dose to patient can be reduced by all of the following except
1. Speed films
2. Filters
3. By increasing target-object distance
4. Decreasing kilovoltage potential
Radiation dose can be reduced by using speed films, filters, and increasing target-object distance.
Letterer-Siwe disease is a disturbance of
1. Protein metabolism
2. Lipid metabolism
3. Mucopolysaccharide metabolism
4. Carbohydrate metabolism
Oral Pathology
Answer: 2
Letterer-Siwe disease is a disturbance of lipid metabolism.
A disease which only affects the formation and eruption of tooth but does not cause hypoplasia is
1. Hypoparathyroidsm
2. Hyperthyroidism
3. Hyperpituitarism
4. Hypoadrenalism
Oral Pathology
Answer: 3
Hyperpituitarism affects the formation and eruption of teeth without causing hypoplasia.
The opsonins which leads to phagocytosis is/are:
1. lgG (Fc fragment)
2. C3b of complement cascade
3. 1gM (Fc fragment) and C5b of complement cascade
4. A and B
Pathology
Answer: 4
Opsonins are molecules that enhance the phagocytosis of antigens by binding to their surfaces and acting as markers or labels that make them more recognizable to phagocytes.
1. lgG (Fc fragment): Immunoglobulin G (IgG) is the most common antibody isotype
in human serum. It plays a crucial role in the secondary immune response. The Fc
region of IgG is the fragment that interacts with Fc receptors present on the
membrane of phagocytic cells. When an antigen is coated with IgG, the Fc
fragments of these antibodies can bind to the Fc receptors, leading to the
activation of the phagocytic process. This is known as antibody-dependent
phagocytosis, where the antibody acts as an opsonin to facilitate the
recognition and engulfment of the antigen by phagocytic cells.
2. C3b of complement cascade: The complement system is a cascade of proteins
that can be activated in response to an infection or the presence of foreign
substances. C3 is a central protein in this system, and when it is cleaved into
C3a and C3b, the latter can bind directly to antigens. C3b acts as an opsonin by
coating the surface of pathogens. The presence of C3b on a microbial surface
allows it to be recognized by complement receptors on phagocytic cells, such as
macrophages. This interaction enhances the efficiency of phagocytosis, as the
receptors can recognize the bound C3b and engulf the antigen more readily.
3. IgM (Fc fragment) and C5b of complement cascade: While IgM is the first
antibody isotype produced in response to an infection and can also opsonize
antigens, it is less efficient than IgG due to its pentameric structure and
lower affinity for phagocytic receptors. However, it is not as commonly
associated with phagocytosis as IgG. Regarding C5b, it is part of the membrane
attack complex (MAC) and is involved in the direct destruction of pathogens
rather than acting as a classical opsonin that leads to phagocytosis. The MAC
assembles on the surface of the antigen and creates pores, leading to osmotic
lysis and destruction of the cell membrane.
Hypersensitively reaction seen in stomatitis venenata is
1. Type I
2. Type II
3. Type III
4. Type IV
Hypersensitivity reactions seen in stomatitis venenata are classified as Type IV.
Scleroderma involves
1. Tightening of oral mucosa and periodontal involvement
2. Multiple palmar keratosia
3. Raynaud"s phenomenon
4. All of the above
Oral Pathology
Answer: 4
Scleroderma involves tightening of oral mucosa, periodontal involvement, and Raynaud's phenomenon.
Which of the following tumors is most aggressive
1) Myxoma
2) Cementoblastoma
3) Ameloblastic fibroma
4) Ameloblastic fibro-odontoma
Oral Pathology
Answer: 1
Myxoma is the most aggressive tumor among the options listed. It is a rare,
benign, but locally aggressive neoplasm that can occur in various anatomic
locations, particularly in the heart and skin. Myxomas are known for their
ability to invade surrounding tissue and cause significant damage to the organ
in which they are found.
Here is a brief description of each tumor type:
1) Myxoma: As mentioned earlier, these are rare but locally
aggressive tumors that can invade and destroy surrounding tissues. They are
typically soft and gelatinous in consistency. When myxomas occur in the heart,
they can obstruct blood flow and cause severe complications.
2) Cementoblastoma: This is a rare, benign tumor that arises
from the periodontal ligament cells that are responsible for producing cementum,
which is the bone-like tissue that anchors teeth in the jaw. Cementoblastomas
are generally slow-growing and less aggressive compared to myxomas.
3) Ameloblastic fibroma: This is a benign, non-invasive tumor
that occurs in the jaw, typically in younger patients. It is composed of both
odontogenic epithelial cells and mesenchymal cells, which are involved in tooth
development. These tumors can cause expansion of the bone but are not as
aggressive as myxomas.
4) Ameloblastic fibro-odontoma: This is a mixed odontogenic
tumor, which means it is composed of both dental epithelial and mesenchymal
cells. It is usually benign and presents as a slowly growing, painless swelling
in the jaw. While it can cause bone expansion, it is less aggressive and
typically does not invade surrounding tissues like a myxoma.
Reticulocytosis is seen in -
1) Hemolytic anemia
2) Megaloblastic anemia
3) Aplastic anemia
4) Iron deficiency
General Pathology
Answer: 1
Reticulocytosis is commonly seen in hemolytic anemia, where there is increased production of red blood cells in response to anemia.