- A. Forms a gelatinous matrix
- B. Metabolizes substrate from saliva
- C. Derives energy from enamel constituents
- D. Lives symbiolically with lactobacillus
Dental Caries
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Streptococcus mutans is considered to be principle etiologic agent of caries because it produces organic acids and it
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The prbable reasons for a high incidence of dental caries in the teenage population relates most directly to
- A. Rapid growth
- B. Frequency of sucrose intake
- C. Negligence in visiting the dentist
- D. Carelessness in oral hygiene habits
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For a bacterium to be seriously considered in the etiology of dental caries, it must
- A. Exist regularly in the dental plaque
- B. Produce extracellular amylopectins
- C. Be lethal for gnotobiotic animals
- D. Produce intracellular dextrans
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Early invading bacteria in carious lesions are called
- A. Microcosm
- B. Pioneer bacteria
- C. Advancing bacteria
- D. Anaerobic bacteria
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The enzyme glucosyl transferase secreted by Streptococcus mutans sythesizes glucans from
- A. Glucose
- B. Fructose
- C. Sucrose
- D. Lactose
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The most pronounced effect on the oral microflora of a reduction in rate of salivary flow is a
- A. Significant increase in number of oral bacteria
- B. Shift towards more acidogenic microflora
- C. Significant decrease in number of oral bacteria
- D. Shift towards more aerobic microflora
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Which of the following organisms is found in deep carious lesions rather than in incipient lesions ?
- A. Streptococci
- B. Lactobacilli
- C. Veillonella
- D. Bateroides
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Cavity formation in a tooth, due to dental caries is due to
- A. Destructive potential of streptococcus mutans
- B. Destructive potential of lactobacillus acidophilus
- C. Lateral spread of caries along DE junction and weakening of the outer covering enamel
- D. Mastectomy force and unrelated to the extent of carious process
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The attachment of the Actinomyces species to the tooth surface is facilitated by
- A. Fimbriae
- B. Cilia
- C. Flagella
- D. Pseudopodia
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Which of the following factors in the stephan’s curve is related to the caries incidence and sugar intake
- A. Physical form of sugar
- B. Frequency of sugar intake
- C. Ph of Plaque
- D. Quantity of sugar intake