title: Periodontal bacteria in adult twins.
abstract: BACKGROUND
  Both environmental and genetic factors are known to influence clinical measures of periodontal disease. The purpose of this study was to determine whether genetic factors similarly influence the presence of specific periodontal bacteria in subgingival plaque.
  
  
  METHODS
  Reared-together and reared-apart monozygous (MZ) and dizygous (DZ) adult twins were examined clinically. Demographic and behavioral information was obtained from each subject by questionnaire. Subgingival plaque samples were obtained from the index teeth, and the presence of P. intermedia, P. gingivalis, A. actinomycetemcomitans, E. corrodens, and F. nucleatum was determined using an immunoassay.
  
  
  RESULTS
  Microbiological and clinical data were available for 169 twin pairs. The subject-based prevalences of the bacteria in the twin groups ranged from 11% for Porphyromonas gingivalis to 40% for F. nucleatum. For all species examined, the concordance rates were not significantly different (P > 0.05) between MZ and DZ twin groups. These findings were apparent despite similar smoking histories, self-reported oral hygiene practices, and antibiotic use in the twin groups. Furthermore, MZ twins reared together were not more similar than MZ reared-apart twins with respect to any bacterial species examined.
  
  
  CONCLUSIONS
  These findings suggest that in a population with access to routine dental care, any effects that host genes and the early family environment have on the presence of specific bacteria in subgingival plaque are not apparent in adulthood. Most twins with disease in this study had early periodontitis. Results from this study may not necessarily be extrapolated to more advanced disease states.
authors.affiliation: Department of Preventive Sciences, School of Dentistry, University of Minnesota, Minneapolis, USA.
authors.forename: B S
authors.initials: BS
authors.lastname: Michalowicz
authors.forename: L F
authors.initials: LF
authors.lastname: Wolff
authors.forename: D
authors.initials: D
authors.lastname: Klump
authors.forename: J E
authors.initials: JE
authors.lastname: Hinrichs
authors.forename: D M
authors.initials: DM
authors.lastname: Aeppli
authors.forename: T J
authors.initials: TJ
authors.lastname: Bouchard
authors.forename: B L
authors.initials: BL
authors.lastname: Pihlstrom
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016976:Aggregatibacter actinomycetemcomitans / Q000254:growth & development; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001419:Bacteria / Q000145:classification* / Q000254:growth & development; D003773:Dental Plaque / Q000235:genetics / Q000382:microbiology*; D016124:Eikenella corrodens / Q000254:growth & development; D004777:Environment; D005260:Female; D016967:Fusobacterium nucleatum / Q000254:growth & development; D006801:Humans; D008297:Male; D008875:Middle Aged; D009910:Oral Hygiene; D010518:Periodontitis / Q000235:genetics / Q000382:microbiology; D010519:Periodontium / Q000382:microbiology*; D016966:Porphyromonas gingivalis / Q000254:growth & development; D015995:Prevalence; D018713:Prevotella intermedia / Q000254:growth & development; D012907:Smoking; D018433:Twin Studies as Topic; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic
chemical_list: D000900:Anti-Bacterial Agents