title: Microbiological changes associated with dental prophylaxis.
abstract: BACKGROUND
  Despite the common application of dental prophylaxis as part of patient therapy, there is little reported that describes the microbiological impact of this treatment.
  
  
  METHODS
  The authors gave 20 healthy college-aged subjects three dental prophylaxes with a fluoride-containing prophylaxis paste during a two-week period and instructed them in oral hygiene. They evaluated the microbiological composition of dental plaque samples collected before and after treatment using DNA probe analysis. They analyzed 40 representative bacterial species in seven bacterial complexes by checkerboard DNA-DNA hybridization assay techniques.
  
  
  RESULTS
  After three dental prophylaxes, the patients' mean Gingival Index score decreased from 0.82 to 0.77, the mean Plaque Index score decreased from 0.72 to zero, and the total number of bacteria per tooth decreased to approximately one-third of the original number. The authors computed two different measures of bacterial presence. The reduction in bacterial numbers was statistically significant and occurred in many species. Bacterial proportion (DNA percentage or percentage of the bacteria per tooth) did not change significantly. Greater reductions in bacterial count occurred in species that showed high numbers before treatment. The total bacterial count decreased by approximately 72 percent of its original level before prophylaxis was initiated.
  
  
  CONCLUSIONS
  Professional dental prophylaxis did not target any particular bacteria or bacterial groups but removed bacteria nonspecifically and in proportion to their initial numbers.
  
  
  CONCLUSIONS
  Repeated dental prophylaxes effect a reduction in bacterial amount that is commensurate with the initial amount, but they do does not alter composition. This suggests that mild gingivitis may be a bacterially nonspecific effect of plaque accumulation and emphasizes the need for regular plaque removal to maintain optimal gingival health.
authors.affiliation: The Forsyth Institute, Boston, Mass. 02115, USA. mgoodson@forsyth.org
authors.forename: J Max
authors.initials: JM
authors.lastname: Goodson
authors.forename: Michael D
authors.initials: MD
authors.lastname: Palys
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Carpino
authors.forename: Elizabeth O
authors.initials: EO
authors.lastname: Regan
authors.forename: Michael
authors.initials: M
authors.lastname: Sweeney
authors.forename: Sigmund S
authors.initials: SS
authors.lastname: Socransky
mesh_terms: D000293:Adolescent; D000328:Adult; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000032:analysis; D003773:Dental Plaque / Q000382:microbiology* / Q000628:therapy; D003777:Dental Prophylaxis; D005260:Female; D005891:Gingivitis / Q000382:microbiology / Q000517:prevention & control; D006801:Humans; D008297:Male; D008875:Middle Aged; D009693:Nucleic Acid Hybridization
chemical_list: D004269:DNA, Bacterial