title: [Colonization of the oral cavity by group mutans streptococci according to age assessed by a semi-quantitative method in saliva].
abstract: OBJECTIVE
  To evaluate the colonization of group mutans streptococci according to age, measuring the amount of bacteria in saliva with a semi-quantitative method in a population attended in public and private dental centers of the Metropolitan Region, Santiago, Chile.
  
  
  METHODS
  Saliva samples were obtained from 14,649 patients aged 5 to 40 years, in one public and 5 private dental centers. Bacteria concentration was estimated by the comparison with a standard counting-chart. The concentration of group mutans streptococci in saliva was test by a 3-way ANOVA.
  
  
  RESULTS
  Bacterial concentration of Streptococcus mutans related with the age of patients was significant (p < 0.001). Bacterial concentration in the preschool age was 4,7 x 10(5) CFU/mL at 5 years, while 6,0 x10(5) CFU/mL at 12 years of age, with a decrease in patients over 30 years. Bacterial concentration was significantly different in the six centers of the study.
  
  
  CONCLUSIONS
  The semi-quantitative method was useful to determine the colonization by Streptococcus mutans according to age. This could help for identifying population at high risk of dental caries and to develop oral health prevention programs in specific populations.
authors: Servicio de Odontología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile. alinossi@gmail.com
authors: Alfredo C
authors: AC
authors: Linossier
authors: Carlos Y
authors: CY
authors: Valenzuela
authors: Eduardo R
authors: ER
authors: Soler
authors: Estela M
authors: EM
authors: Contreras
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D002677:Chile; D015169:Colony Count, Microbial / Q000379:methods*; D003740:Dental Clinics; D005260:Female; D006801:Humans; D008297:Male; D012463:Saliva / Q000382:microbiology*; D013295:Streptococcus mutans / Q000302:isolation & purification*; D014505:Urban Population; D055815:Young Adult