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)

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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. 

Taste buds are predominantly located in:

# Taste buds are predominantly located in:

A. Circumvallate papilla

B. Filiform papilla

C. Foliate papilla

D. Fungiform papilla

The correct answer is A. Circumvallate papilla.

# Circumvallate papilla - Present in front of the V shaped sulcus terminalis

- Large in size and 8-12 in number

- Contain many taste buds

- Von Ebner's salivary gland ducts open into its trough

# Filiform papilla/ conical papilla 

- Keratinized threadlike and give the tongue a characteristic velvety appearance

- Smallest and most numerous papillae

- Contain no taste buds

# Fungiform papillae

- Mushroom shaped, numerous near the tip and margins of the tongue

- contain few taste buds

- Distinguished by their bright red color

# Foliate papilla

- Present on the lateral border of posterior parts of the tongue

- Contain taste buds

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Passavant’s muscle is formed by:

 # Passavant’s muscle is formed by:

A. Palatoglossus

B. Palatopharyngeus

C. Styloglossus

D. Superior constrictor

The correct answer is B. Palatopharyngeus.

The upper fibres of palatopharyngeus form a sphincter internal to superior constrictor. These fibres constitute Passavant's muscle, which on contraction raises Passavant's ridge on the posterior wall of nasopharynx, but Passavant's ridge is present within Superior constrictor. 

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Sensory supply of soft palate

 # The sensory supply of soft palate is from:

A. Glossopharyngeal and vagus nerve

B. Maxillary nerve and mandibular nerve

C. Glossopharyngeal nerve and maxillary nerve

D. None of the above

The correct answer is C. Glossopharyngeal nerve and maxillary nerve.

General sensory nerves are derived from: a) The middle and posterior lesser palatine nerves, which are branches of the maxillary nerve through the pterygopalatine ganglion and b) from pharyngeal branch of the glossopharyngeal nerve. 

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Which muscles make up the pterygomandibular raphe:

 # Which muscles make up the pterygomandibular raphe?

A. Masseter anteriorly and palatopharyngeus posteriorly

B. Masseter anteriorly and middle pterygoid posteriorly

C. Buccinator anteriorly and superior constrictor posteriorly

D. Buccinator anteriorly and middle constrictor posteriorly

The correct answer is C. Buccinator anteriorly and superior constrictor posteriorly.

The pterygomandibular raphe is made up of interlacing tendinous fibres. It is attached above to the pterygoid hamulus (at the lower end of the medial pterygoid plate) and below to the posterior end of the mylohyoid line of the mandible. The raphe gives attachment anteriorly to fibres of the buccinator, and posteriorly to fibres of the superior constrictor of the pharynx. 

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AIIMS MDS ENTRANCE EXAM PAST QUESTIONS NOV 2001

 

AIIMS MDS ENTRANCE EXAM PAST QUESTIONS NOV 2001 by Raman Dhungel on Scribd