Which of the following cements have highest water solubility?

 # Which of the following cements have highest water solubility? 

A. Zinc phosphate 

B. Zinc oxide eugenol 

C. Zinc silicophosphate 

D. Zinc polycarboxylate 

The correct answer is C. Zinc silicophosphate.

Of the given choices, ZOE cements have the highest solubility in oral environment. But, water solubility of ZOE is less while that of silicophosphate is quite high. The oral solubility is different from water solubility. This is because the oral environment is mildly acidic while the water is neutral. Thus, in oral environment, ZOE has maximum solubility while in water, silicophosphate has maximum water solubility.

Tumor suppressor gene in head and neck cancer is:

 # Tumor suppressor gene in head and neck cancer is: 

A. Erb-b 

B. C-myc 

C. Bcl 

D. p16INK4A 

The correct answer is D. p16INK4A.

Tumor suppressor genes have been associated with sites of chromosome abnormalities where loss of genetic nucleic segments has been reported to commonly involve chromosome arms 3p, 4q, 8p, 9p, 11q, 13q, and 17p. TSGs involved in HNSCC are P53, Rb (retinoblastoma), and p16INK4A. Other candidates include FHIT (fragile histidine triad), APC (adenomatous polyposis coli), DOC1 VHL (gene for von Hippel‐Lindau syndrome), and TGF‐R‐II (gene for transforming growth factor type II receptor).

Ref: Burket's Oral Medicine, 13th Edition.

Non scrappable white papules intermixed with areas of erythema and erosion most likely falls under:

 # Non scrappable white papules intermixed with areas of erythema and erosion most likely falls under: 

A. Candidiasis 

B. Erythroleukoplakia 

C. Leukoplakia 

D. Erythroplakia 

The correct answer is B. Erythroleukoplakia.

The term 'non homogeneous' is ascribed to lesions with two different features, usually having both red and white areas, but also to all those without redness but containing verruciform exophytic elements. Due to the combined appearance of white and red areas, the nonhomogeneous oral leukoplakia has also been called erythroleukoplakia and speckled leucoplakia. The clinical manifestation of the white component may vary from large white verrucous areas to small nodular structures. If the surface texture is homogeneous but contains verrucous, papillary (nodular), or exophytic components, the leukoplakia is also regarded as nonhomogeneous.

The glycoprotein antigen chiefly detected in pemphigoids is:

 # The glycoprotein antigen chiefly detected in pemphigoids is: 

A. BP 180 and 230 

B. DSG 2 and 3 

C. BP 130 and 280 

D. DSG 1 and 4 

The correct answer is A. BP 180 and 230.

Bullous Pemphigoid is an autoimmune disease caused by the binding of autoantibodies to specific antigens found in the lamina lucida region of the basement membrane on the hemidesmosomes of epithelial basal cells. These antigens are glycoproteins referred to as bullous pemphigoid antigens, BP 180 and BP 230. Binding of antibody to antigen activates both leukocytes and complement, causing localized damage to the basement membrane, resulting in vesicle formation in the subepithelial region.

Blisters containing clear fluid, less than 1cm in diameter is:

 # Blisters containing clear fluid, less than 1cm in diameter is: 

A. Vesicle 

B. Bulla 

C. Pustule 

D. Nodule 

The correct answer is A. Vesicle.

Vesicles: These are small blisters containing clear fluid that are less than 1 cm in diameter.

Bullae: These are elevated blisters containing clear fluid that are greater than 1 cm in diameter.

Pustules: These are blisters containing purulent material and appear yellow.

Nodules: These lesions are present within the deep mucosa. The lesions may also protrude above the mucosa forming a characteristic dome‐shaped structure. A good example of an oral mucosal nodule is the irritation fibroma.

Ref:  Burket's Oral Medicine, 13th Edition.

Dressler syndrome is a complication of:

 # Dressler syndrome is a complication of:

A. Hypertension

B. Pericarditis

C. Mitral stenosis

D. Myocardial infarction

The correct answer is D. Myocardial infarction.

Dressler syndrome is a secondary form of pericarditis that occurs in the setting of injury to the heart or the pericardium (the outer lining of the heart). It consists of fever, pleuritic pain, pericarditis and/or a pericardial effusion.

Dressler syndrome is also known as postmyocardial infarction syndrome and the term is sometimes used to refer to post-pericardiotomy pericarditis.

It was first characterized by William Dressler at Maimonides Medical Center in 1956.

Beyron point is located at:

 # Beyron point is located at:

A. 13 mm anterior to posterior margin of tragus on a line from center of tragus to outer canthus 

B. 11 mm anterior to posterior margin of tragus on a line from parallel to and 7 mm below FHP 

C. 10 mm anterior to posterior margin of tragus on a line from center of tragus to outer canthus 

D. 13 mm anterior to tragus on a line from base of tragus to outer canthus 

The correct answer is A.  13 mm anterior to posterior margin of tragus on a line from center of tragus to outer canthus. 

The first step in placing a face bow is to locate the hinge axis on the skin on the each side of the patients face. One frequently recommended method is to position the condyle rods on a line extending from the counter canthus of the eye to the top of the tragus of the ear and approximately 13 mm in front of the external auditory meatus is called Beyron Point.This placement generally locates the rods within 5mm of the true center of the opening axis of the jaws. The imaginary line joining the two Beyron points is an approximate hinge axis.