Medical Mcqs Practice Test

Question 1

The attachment of the Actinomyces species to the tooth surface is facilitated by____________?

Accepted Answer

A.	Fimbriae

Question 2

Which of the following factors in the stephan’s curve is related to the caries incidence and sugar intake______________?

Accepted Answer

C.	Ph of Plaque

Question 3

Cavity formation in a tooth, due to dental caries is due to______________?

Accepted Answer

C.	Lateral spread of caries along DE junction and weakening of the outer covering enamel

Question 4

The most pronounced effect on the oral microflora of a reduction in rate of salivary flow is a_____________?

Accepted Answer

B.	Shift towards more acidogenic microflora

Question 5

Which of the following organisms is found in deep carious lesions rather than in incipient lesions ?

Accepted Answer

B.	Lactobacilli

Question 6

Early invading bacteria in carious lesions are called___________?

Accepted Answer

B.	Pioneer bacteria

Question 7

The prbable reasons for a high incidence of dental caries in the teenage population relates most directly to______________?

Accepted Answer

B.	Frequency of sucrose intake

Question 8

The enzyme glucosyl transferase secreted by Streptococcus mutans sythesizes glucans from_____________?

Accepted Answer

C.	Sucrose

Question 9

For a bacterium to be seriously considered in the etiology of dental caries, it must______________?

Accepted Answer

A.	Exist regularly in the dental plaque

Question 10

Streptococcus mutans is considered to be principle etiologic agent of caries because it produces organic acids and it ________________?

Accepted Answer

A.	Forms a gelatinous matrix

Question 11

Which tooth in the permanent dentition is the most susceptible to dental caries ?

Accepted Answer

C.	Mandibular 1st molar

Question 12

Smooth surface caries is characterized by spread of caries in enamel and dentin as cones. These alignment in enamel and dentin is____________?

Accepted Answer

B.	Apex to base

Question 13

Oral foci of miller’s are seen in_______________?

Accepted Answer

A.	Dental caries

Question 14

Bacteria responsible for initiation of caries is _________________?

Accepted Answer

B.	Strep. mutans

Question 15

S. mutans is involved in dental caries initiation Other bacteria also involved is______________?

Accepted Answer

C.	S. sanguis

Question 16

Widely accepted theory of dental caries_____________?

Accepted Answer

C.	Acidogenic theory

Question 17

The number of dentinal zones in dentinal caries is_____________?

Accepted Answer

D.	Five

Question 18

In a patient with reduced salivary flow the carious incidence is_______________?

Accepted Answer

A.	More than the patient with normal salivary flow

Question 19

The extra – cellular polysaccharide sythesized by cariogenic streptococci in the presence of excess sucrose are best described as_______________?

Accepted Answer

B.	Dextran-like glucan

Question 20

Lactobacilli are numerous in caious lesions because they______________?

Accepted Answer

D.	Are secondary invaders