Buttressing bone formation is:

# Buttressing bone formation is:

A. Congenital abnormality

B. Occurs endosteally

C. Occurs periosteally

D. Due to trauma from occlusion

 

The correct answer is D. Due to trauma from occlusion. 

- When excessive occlusal forces resorb bone, the bone attempts to reinforced the thinned bony trabeculae with new bone. This attempt to compensate for lost bone is called buttressing bone formation - may be central or peripheral. Peripheral butteressing boine formation is also called lipping. 

CLICK HERE FOR MORE MCQs

Treatment of odontogenic keratocyst extending into the mandibular ramus is:

 # Treatment of odontogenic keratocyst extending into the mandibular ramus is:

A. Enucleation without curettage

B. Marsupialization without curettage

C. Enucleation with peripheral osteotomy

D. Enbloc dissection

The correct answer is C. Enucleation with peripheral osteotomy.

Enucleation with curettage: Enucleation with curettage means that after enucleation, a curette or bur is used to remove 1 or 2 mm of bone around the entire periphery of the cystic cavity. This is done to remove any remaining epithelial cells that may be present in the periphery of the cystic wall or bony cavity.

CLICK HERE FOR MORE MCQs

Peripheral nerve block - Longest duration of action

 # In peripheral nerve block, which of the following local anesthetics has the longest duration of action?

A. Bupivacaine

B. Cocaine

C. Lignocaine

D. Prilocaine

The correct answer is A. Bupivacaine.

Bupivacaine and Etidocaine are long acting anesthetics with a duration of action about 180 minutes or even longer and this is due to their increased protein binding property. 

Bupivacaine is a potent agent capable of producing prolonged anesthesia. Its long duration of action and its tendency to provide more sensory than motor block has made it a popular drug for providing prolonged analgesia during  labor or the postoperative period. 

Bupivacaine and etidocaine are more cardiotoxic than equieffective doses of lidocaine. 

CLICK HERE FOR MORE MCQs

Bisecting angle technique is based upon:

 # Bisecting angle technique is based upon:

A. ALARA Principle

B. SLOB Rule

C. Rule of Isometry

D. Convergence

The correct answer is C. Rule of Isometry.

Cieszynski's Rule of Isometry

- Used in bisecting angle techniqiue of radiograph

- Two traingles are equal when they share one complete side and have two equal angles.

- An imaginary line that bisects the angle made by the film and the long axis of the teeth is constructed and central ray of the beam is directed at right angles to this bisector which forms two triangles with two equal angles and a common side (the imaginary bisector)

Disadvantages:

- To correctly reproduce the length of each root of a multirooted tooth, the central beam must be angled differently for each root.

- The alveolar ridge often projects more coronally than its true position.

CLICK HERE FOR MORE MCQs

Nucleus in Reed-Sternberg cell is also described as:

 # Nucleus in Reed-Sternberg cell is also described as ?

A. “Owl’s eyes” appearance

B. “Spectacle” appearance

C. “Ghost” appearance

D. “Moon” appearance

The correct answer is A. Owl's eyes appearance.

A Reed-Sternberg cell is  a large cell with a bilobed nucleus and prominent nucleoli giving an “owl’s eyes” appearance.

CLICK HERE FOR MORE MCQs

Tetracycline cause tooth discoloration due to formation of:

 # Tetracycline cause tooth discoloration due to formation of:

A. Calcium oxalate

B. Orthophosphate

C. Tetracalcium phosphate

D. Calcium oxide

The correct answer is B. Orthophosphate.

- Presence of tetracycline in the bloodstream promotes deposition of the drug in the developing enamel and dentin of teeth and bones by binding to calcium to form tetracycline-calcium-orthophosphate.

- The minimum amount required for tooth discoloration is 21 mg/kg body weight. 

- The complex causes discoloration upon eruption and exposure to sun (UV light).

 

# The discoloration appears as:

a) Oxytetracycline (Terramycin)  = Light yellow

b) Tetracycline (Achromycin), Demeclocycline = Yellow

c) Synthetic tetracycline (Minocycline) = Green to dark gray

d) Chlortetracycline (Aureomycin) = Gray - brown (Worst staining)

e) Doxycycline and Oxytetracycline = Light Yellow (least staining)

CLICK HERE FOR ALL MCQs

How much is your worth?

 A bar of iron costs $5, made into horse-shoes its worth is $12, made into needles its worth is $3500, made into balance springs for watches its worth is $300,000. Your own value is determined also by what you are able to make of yourself.