most effective antimicrobial agent

Which of the following has been shown to be the most effective antimicrobial agent for reducing plaque and gingivitis long-term?

• Stannous fluoride 

• Phenolic compounds 

• Chlorhexidine 

• Quaternary ammonium compounds 

All of the following bacteria may be etiologically related to dental caries except:

• Streptococcus mutans 

• Actinomyces viscosus 

• Actinobacillus actinomycetemcomitans (AA) 

• Streptococcus salivarius 

• Streptococcus sanguis 

• Actinomyces naeslundii 

• Actinomyces israeli 

• Lactobacillus casei 

The principal oral site for the growth of spirochetes  fusobacteria and other gram-negative anaerobes is:

• Saliva

• Calculus

• The gingival margin

• The gingival sulcus

All of the following statements concerning bacterial plaque are true except:

• It is the key etiologic agent in the initiation of gingivitis and periodontal disease

• It is an accumulation of a mixed bacterial community in a dextran matrix

• It forms on a cleaned tooth within minutes

• It is composed of solids (80%; 95% of which are bacteria) and water (20%)

• There are two categories: supragingival and subgingival plaque

• Different bacteria may be found in plaque (cocci, rods, and filaments) and their proportions change with time, diet, and location

Which of the following statements are true concerning supragingival and subgingival plaque except:

• Subgingival plaque can be attached or loosely adherent (epithelium associated)

• Supragingival plaque is attached or tooth associated

• Subgingival plaque is dominated by gram-negative rods

• Supragingival plaque is dominated by gram-positive cocci

• Supragingival plaque has more anaerobes than subgingival plaque

All of the following statements concerning calculus are true except:

• It is calcified or mineralized bacterial plaque

• It forms on natural teeth, dentures, and other dental prostheses

• The surface is very rough and is covered by a layer of bacterial plaque

• Inorganic material makes up about 10-15% of the composition while organic material and water make up about 70-90% of the composition

• Its main role in periodontal disease is to serve as a collection site for more bacteria

Which one of the following organisms is commonly implicated with the etiology of acute necrotizing ulcerative gingivitis (ANUG) "trench mouth "?

• Streptococcus sanguis 

• Actinomyces israelii 

• Prevotella intermedia 

• Streptococcus uberis 

Cytokines are:

• Insoluble mediators that play and important roll in blood clotting

• Soluble mediators that play an important role in immunity

• Soluble mediators that play an important role in genetic recombination

• Insoluble mediators that play an important role in glomerular filtration