Question 1

Supragingival plaque is associated with gingivitis and periodontitis,whereas subgingival plaque is associated with caries and gingivitis.&#10;A)First statement is true,second statement is false.&#10;B)First statement is false,second statement is true.&#10;C)Both statements are true.&#10;D)Both statements are false.

Accepted Answer

D)Supragingival plaque is associated with caries and gingivitis,whereas subgingival plaque is associated with gingivitis and periodontitis.

Question 2

In dental plaque metabolism,after the microorganism is exposed to sucrose,they produce:&#10;A)Acid&#10;B)Intracellular polysaccharides&#10;C)Extracellular polysaccharides&#10;D)All of the above

Accepted Answer

D)Almost immediately following exposure of these microorganisms to sucrose,they produce (1)acid,(2)intracellular polysaccharides,which provide a reserve source of energy for each bacterium,much like glycogen does for human cells,⁸⁸ and (3)extracellular polysaccharides including glucans (dextran)⁸⁹and fructans (levan).⁹⁰

Question 3

What factors may affect the onset of periodontal diseases?&#10;A)Plaque&#10;B)Host defense mechanisms&#10;C)Exogenous antimicrobial agents&#10;D)All of the above

Accepted Answer

A)Periodontal diseases arise because of complex changes in plaque ecology and are affected by many factors in the host's protective responses.Current research indicates that bacteria growing in biofilms may be resistant to the effects of host defense mechanisms and exogenous antimicrobial agents.

Question 4

The coating of salivary origin that forms on exposed tooth surfaces is called the:&#10;A)Subsurface pellicle&#10;B)Acquired pellicle&#10;C)Basil lamina&#10;D)Reduced enamel epithelium

Accepted Answer

B)The coating of salivary origin that forms on exposed tooth surfaces is called the acquired pellicle.

Question 5

Which of the following can be used to prevent the excess accumulation of plaque?&#10;A)Host defense mechanisms&#10;B)Effective toothbrushing&#10;C)Biofilm lozenges&#10;D)No prevention necessary

Accepted Answer

B)Regular toothbrushing and flossing can remove dental plaque and control its formation.

Question 6

Adhesion is mediated by a variety of bonding mechanisms,which include:&#10;A)Exogenous antimicrobial agents&#10;B)Etching agents&#10;C)Physiochemical interactions&#10;D)Antimicrobial interactions

Accepted Answer

C)Adhesion is mediated by a variety of bonding mechanisms,including physicochemical and electrostatic interactions,as well as stereo-chemical interactions between bacterial adhesions and receptors in the acquired pellicle and bacterial surfaces.

Question 7

The primary colonizers in dental plaque biofilm tend to be cocci.They also tend to be aerobic.&#10;A)First statement is true,second statement is false.&#10;B)First statement is false,second statement is true.&#10;C)Both statements are true.&#10;D)Both statements are false.

Accepted Answer

C)Cocci are probably the first to adhere because they are small and round and,therefore,have a smaller energy barrier to overcome than other bacterial forms⁷³The first or primary colonizers tend to be aerobic (oxygen-tolerant)bacteria including Neisseria and Rothia.

Question 8

Pyrophosphates decrease the formation of which of the following?&#10;A)Plaque&#10;B)Calculus&#10;C)Early carious lesions&#10;D)Gingivitis

Accepted Answer

B)Several agents are currently available to reduce calculus formation,including dentifrices that contain pyrophosphate.

Question 9

Supragingival calculus is 60% mineralized,subgingival calculus is 30% mineralized.&#10;A)First statement is true,second statement is false.&#10;B)First statement is false,second statement is true.&#10;C)Both statements are true.&#10;D)Both statements are false.

Accepted Answer

D)Subgingival calculus is about 60% mineralized,whereas supragingival calculus is only about 30% mineralized.

Question 10

Subgingival calculus derives their mineral from which of the following that is found in the sulcus and periodontal pocket.&#10;A)Sulcular epithelium&#10;B)Mucogingival fluid&#10;C)Inflammatory exudate&#10;D)Endotoxins

Accepted Answer

C)Subgingival calculus derives its minerals from the inflammatory exudate in the sulcus and periodontal pocket.

Deck 4: Dental Plaque Biofilm