title: Transmission of periodontal bacteria and models of infection.
abstract: BACKGROUND
  Bacteria play an essential role in the aetiology of periodontitis. Most bacterial species isolated from subgingival plaque are indigenous to the oral cavity. Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis are detected infrequently in periodontal health, which makes these species prime candidates to study person-to-person transmission. The aim of the present study was to review the literature on transmission of these periodontal bacterial species.
  
  
  METHODS
  We review the literature on bacterial typing techniques and summarize the information on clonal distribution of A. actinomycetemcomitans and P. gingivalis in family units based on different typing techniques in order to establish the likelihood for person-to-person transmission of these periodontal pathogens.
  
  
  RESULTS
  Vertical transmission of A. actinomycetemcomitans is estimated to be between 30% and 60%, whereas vertical transmission of P. gingivalis has rarely been observed. Horizontal transmission between spouses ranges between 14% and 60% for A. actinomycetemcomitans and between 30% and 75% for P. gingivalis. There is some evidence to show that cohabitation with a periodontitis patient influences the periodontal status of the spouse; however, substantially more information is needed to prove this hypothesis.
  
  
  CONCLUSIONS
  Transmission of putative periodontal pathogens between family members has been shown. The clinical consequences of these events have been poorly documented. Based on the current knowledge, screening for and prevention of transmission of specific virulent clones of A. actinomycetemcomitans may be feasible and effective in preventing some forms of periodontal disease. P. gingivalis is usually recovered from diseased adult subjects, and transmission of this pathogens seems largely restricted to adult individuals. Horizontal transmission of P. gingivalis may therefore be controlled by periodontal treatment involving elimination or significant suppression of the pathogen in diseased individuals and by a high standard of oral hygiene.
authors.affiliation: Academic Centre for Dentistry Amsterdam, Department of Oral Microbiology, Amsterdam, The Netherlands. aj.vanwinkelhoff@vumc.nl
authors.forename: A J
authors.initials: AJ
authors.lastname: Van Winkelhoff
authors.forename: K
authors.initials: K
authors.lastname: Boutaga
mesh_terms: D000189:Actinobacillus Infections / Q000635:transmission; D000293:Adolescent; D000328:Adult; D016976:Aggregatibacter actinomycetemcomitans / Q000502:physiology*; D015373:Bacterial Typing Techniques; D016866:Bacteroidaceae Infections / Q000635:transmission*; D002648:Child; D018562:Disease Transmission, Infectious; D005192:Family Health; D006801:Humans; D018445:Infectious Disease Transmission, Vertical; D010518:Periodontitis / Q000382:microbiology*; D016966:Porphyromonas gingivalis / Q000502:physiology*