title: Effect of bovine milk on Streptococcus mutans biofilm cariogenic properties and enamel and dentin demineralization.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the effect of whole bovine milk on Streptococcus mutans biofilms and on demineralization of enamel and root dentin.
  
  
  METHODS
  S mutans UA159 biofilms were cultured on enamel and dentin bovine slabs of known surface hardness  (SH) and exposed (8x/day) to 10% sucrose (positive control), whole bovine milk, and 4.5% lactose. Biofilm acidogenicity was estimated by medium pH (2x/day). After 4 days for dentin and 5 days for enamel, biofilms were collected to obtain biomass, viable bacteria, total protein, and intra-  and extracellular polysaccharides. Final SH was measured on the slabs. Demineralization was calculated as percentage of SH loss (%SHL). Differences were determined by analysis of variance and Tukey's test (P<.05).
  
  
  RESULTS
  Biofilms formed on both substrates under 10% sucrose showed  higher acidogenicity, biomass, protein concentration, insoluble polysaccharides, and %SHL than those treated with milk or lactose (P<.05), which did not differ in any parameter (P>.05). Higher bacterial counts were obtained from biofilms treated with milk on enamel, but not on dentin.  Dentin was significantly more demineralized by milk than enamel (P<.05).
  
  
  CONCLUSIONS
  Although bovine milk appears to be less cariogenic than sucrose, this dairy product should not be considered caries-safe.
authors.affiliation: Dental School of the University of Talca, the University of Talca, Talca, Chile.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Muñoz-Sandoval
authors.forename: María José
authors.initials: MJ
authors.lastname: Muñoz-Cifuentes
authors.forename: Rodrigo A
authors.initials: RA
authors.lastname: Giacaman
authors.forename: Renzo A
authors.initials: RA
authors.lastname: Ccahuana-Vasquez
authors.forename: Jaime A
authors.initials: JA
authors.lastname: Cury
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D018441:Biofilms; D002326:Cariogenic Agents / Q000009:adverse effects*; D002417:Cattle; D015169:Colony Count, Microbial; D003743:Dental Enamel / Q000382:microbiology / Q000473:pathology; D003804:Dentin / Q000382:microbiology / Q000473:pathology; D006244:Hardness; D006863:Hydrogen-Ion Concentration; D007785:Lactose / Q000009:adverse effects; D008892:Milk / Q000009:adverse effects*; D018709:Statistics, Nonparametric; D013295:Streptococcus mutans; D013395:Sucrose / Q000009:adverse effects; D017001:Tooth Demineralization / Q000209:etiology*
chemical_list: D002326:Cariogenic Agents; D013395:Sucrose; D007785:Lactose