title: Hydrophobicity test in mutans streptococci.
abstract: Kinetic hydrophobic measurements were performed by confronting 40 mutans streptococci from thirty 10- to 20-year-old patients with 200 ml hexadecane (Sigma). Fourteen patients had high dental caries risk (Group A), dmft + DMFT > 5 with 3 or more active caries, and 16 had low dental caries risk (Group B), dmft + DMFT < 3 without active caries. Twenty bacteria from Group A and 20 bacteria from Group B were typed using De La Higuera's procedure and confirmed by API strip (bio-Merieux). From the 14 patients in Group A we obtained 12 S. mutans (8 hydrophobic/4 non-hydrophobic), 5 S. sobrinus (4 hydrophobic/1 non-hydrophobic) and 3 S. rattus (hydrophobic). From the 16 patients in Group B we obtained 11 Streptococcus mutans (10 non-hydrophobic/1 hydrophobic), 7 Streptococcus sobrinus (6 non-hydrophobic/ 1 hydrophobic) and 2 Streptococcus rattus (hydrophobic). Patients with high dental caries risk have a higher prevalence of hydrophobic bacteria than patients with low dental caries risk (p = 0.0003). All typed S. rattus were hydrophobic.
authors.affiliation: Department of Microbiology, School of Dentistry, National University of Rosario, Argentina. phermida@fodonto.unr.edu.ar
authors.forename: Perla Hermida
authors.initials: PH
authors.lastname: Lucena
authors.forename: Luciana
authors.initials: L
authors.lastname: Biondi
authors.forename: Ramón
authors.initials: R
authors.lastname: de Torres
mesh_terms: D000293:Adolescent; D000473:Alkanes / Q000737:chemistry; D001422:Bacterial Adhesion / Q000502:physiology; D002648:Child; D004245:DMF Index; D003731:Dental Caries / Q000382:microbiology; D003733:Dental Caries Susceptibility / Q000502:physiology*; D005260:Female; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008297:Male; D013291:Streptococcus / Q000145:classification / Q000502:physiology; D013295:Streptococcus mutans / Q000502:physiology*; D016986:Streptococcus sobrinus / Q000502:physiology*; D055815:Young Adult
chemical_list: D000473:Alkanes; C007932:n-hexadecane