Chromatolysis is:

 # Chromatolysis is:

A. Disintegration of nucleus

B. Disintegration of golgi apparatus

C. Disappearance of Nissl granules

D. Decrease in cell size

The correct answer is C. Disappearance of Nissl granules.

Chromatolysis is a reactive change that occurs in the cell body of damaged neurons. It involves the dispersal and redistribution of Nissl substance (rough endoplasmic reticulum and polyribosomes) to meet an increased demand for protein synthesis. 

Salivary protein which prevents transmission of HIV via saliva is:

 # Salivary protein which prevents transmission of HIV via saliva is:

A. Sialoperoxidase

B. Secretory IgA

C. Salivary leukocyte protease inhibitor

D. Histidine rich proteins

The correct answer is C. Salivary leukocyte protease inhibitor.

SLPI blocks HIV-1 infection of macrophages and primary T cells at concentrations (1–10 μg/mL) that occur naturally in saliva (Shugars and Wahl, 1998). These findings suggest that SLPI may be partially responsible for the low rate of oral transmission of HIV-1.

Rotational force of extraction is used for delivery of which tooth out of the socket?

 # Rotational force of extraction is used for delivery of which tooth out of the socket?

A. Upper central incisors and lower premolars

B. Upper centrals and lateral incisors

C. Upper and lower central incisors

D. Upper premolars and lower central incisors

The correct answer is A. Upper central incisors and lower premolars.

Rotational pressure, as the name implies, rotates the tooth, which causes some internal expansion of the tooth socket and tearing of periodontal ligaments. Teeth with single, conical roots (such as maxillary incisors and mandibular premolars) and those with roots that are not curved are most amenable to luxation by this technique. Teeth that have other than conical roots or that have multiple roots—especially if those roots are curved—are more likely to fracture under this type of pressure.

Ref: Contemporary Oral and Maxillofacial Surgery 6th Edition, Hupp

Metapex is a combination of:

 # Metapex is a combination of: 

A. Calcium hydroxide + ZOE

B. ZOE + Iodoform

C. Calcium hydroxide + Iodoform

D. Calcium hydroxide + GIC

The correct answer is C. Calcium hydroxide + Iodoform.

Metapex = Calcium hydroxide + iodoform 

Vitapex = Calcium hydroxide + iodoform + Silicon based oil (better flow able property) 

• Ideal material for obturating primary teeth = same resorption rate as of primary tooth roots 

• Both Vitapex & metapex has same resorption rate to primary tooth root but due to better flow able property of vitapex its nearly IDEAL and best material for obturation in primary teeth.