title: Correlation of Streptococcus mutans and Streptococcus sanguinis colonization and ex vivo hydrogen peroxide production in carious lesion-free and high caries adults.
abstract: OBJECTIVE
  This study was conducted to estimate oral colonization by Streptococcus mutans and Streptococcus sanguinis in adults with high and without any caries experience. Furthermore, differences in the amount of hydrogen peroxide (H2O2) produced by S. sanguinis isolated from both groups were assessed.
  
  
  METHODS
  Forty adults were divided into: (i) carious lesion-free, without any carious lesion, assessed by the International Caries Detection and Assessment System (ICDAS), or restoration, (CF) and (ii) high caries experience (HC). Saliva samples were collected and seeded on respective agar-plates for enumeration of total streptococci, S. mutans and S. sanguinis (CFU/mL) and compared between groups. Additionally, S. sanguinis colonies obtained from both groups were inoculated on Prussian blue agar for H2O2 detection. Production of H2O2 was quantified and compared between the two groups. S. sanguinis counts were significantly higher in CF than HC individuals (p<0.05). Conversely, S. mutans showed significantly higher levels in HC than CF subjects (p<0.001). S. sanguinis colonies from CF individuals produced significantly larger H2O2 halos compared with HC subjects.
  
  
  CONCLUSIONS
  S. sanguinis predominates over S. mutans in saliva of adults without caries experience. In those people, S. sanguinis produces more H2O2ex vivo.
authors.affiliation: Cariology Unit, Department of Oral Rehabilitation and Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), University of Talca, Talca, Chile. Electronic address: giacaman@utalca.cl.
authors.forename: Rodrigo A
authors.initials: RA
authors.lastname: Giacaman
authors.affiliation: Cariology Unit, Department of Oral Rehabilitation and Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), University of Talca, Talca, Chile.
authors.forename: Sebastián
authors.initials: S
authors.lastname: Torres
authors.affiliation: Cariology Unit, Department of Oral Rehabilitation and Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), University of Talca, Talca, Chile.
authors.forename: Yenifer
authors.initials: Y
authors.lastname: Gómez
authors.affiliation: Cariology Unit, Department of Oral Rehabilitation and Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), University of Talca, Talca, Chile.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Muñoz-Sandoval
authors.affiliation: Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; College of Dentistry, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
authors.forename: Jens
authors.initials: J
authors.lastname: Kreth
mesh_terms: D000328:Adult; D018441:Biofilms; D015169:Colony Count, Microbial; D003731:Dental Caries / Q000382:microbiology*; D005260:Female; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism*; D008297:Male; D010641:Phenotype; D013295:Streptococcus mutans / Q000302:isolation & purification / Q000502:physiology*; D013298:Streptococcus sanguis / Q000302:isolation & purification / Q000502:physiology*
chemical_list: D006861:Hydrogen Peroxide
keywords: Bacterial competition; Bacterial interaction; Dental caries; Oral biofilm; Streptococcus mutans; Streptococcus sanguinis