title: The effects of fluoride and mineralising treatments on plaque microcosm Ca, P and F, pH responses and cariogenicity.
abstract: OBJECTIVE
  To investigate the effects of fluoride (F), calcium-phosphate-monofluorophosphate-urea (CPMU) mineralising solution, and casein on plaque pH and calcium (Ca), phosphate (P) and F content, and the ability of plaque to induce carious lesions in enamel.
  
  
  METHODS
  Plaque microcosms were cultured in cariogenic growth conditions on enamel specimens for 28d in a "multiplaque artificial mouth". The plaques were supplied 5 times daily with 10% sucrose (1.5 ml over 6 min) over a 12h period followed by a 12h rest period. Duplicate plaques were pulsed with 0, 1000, 3000 and 5000 ppm F (1.5 ml over 6 min) or 2% w/v casein (1.25 ml over 30 min) twice daily. One of each pair was also pulsed with CPMU (1.5 ml over 6 min). Plaque pH was monitored during growth. After 28 days' culture, plaque Ca, P and F levels were quantified and lesion depth in enamel was measured by backscattered electron SEM.
  
  
  RESULTS
  F pulses raised the plaque pH, which was otherwise below 4 during sucrose pulsing, while CPMU hastened and raised the recovery pH. Plaque Ca, P and F levels substantially increased with increasing concentrations of applied F, particularly in the presence of CPMU (P < 0.01). In the absence of either F or CPMU, enamel lesions were formed with extensive enamel loss.
  
  
  CONCLUSIONS
  CPMU and F supplied to plaque microcosms substantially reduce plaque cariogenicity to enamel under highly cariogenic experimental conditions. This was associated with an increase in plaque pH, plaque F and Ca levels.
authors.affiliation: Dental Research Group, Department of Pathology and Molecular Medicine, University of Otago, Wellington, New Zealand. linny.angker@otago.ac.nz
authors.forename: Linny
authors.initials: L
authors.lastname: Angker
authors.forename: Michael V
authors.initials: MV
authors.lastname: Swain
authors.forename: Lisa
authors.initials: L
authors.lastname: Wong
authors.forename: Chris
authors.initials: C
authors.lastname: Sissons
mesh_terms: D018533:Biomass; D002118:Calcium / Q000032:analysis*; D002130:Calcium Phosphates / Q000494:pharmacology; D002326:Cariogenic Agents / Q000494:pharmacology; D002327:Cariostatic Agents / Q000008:administration & dosage / Q000494:pharmacology*; D002364:Caseins / Q000494:pharmacology; D002614:Chelating Agents / Q000494:pharmacology; D003731:Dental Caries / Q000473:pathology*; D003743:Dental Enamel / Q000473:pathology; D003773:Dental Plaque / Q000737:chemistry* / Q000503:physiopathology; D005459:Fluorides / Q000008:administration & dosage / Q000032:analysis / Q000494:pharmacology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D010710:Phosphates / Q000494:pharmacology; D010758:Phosphorus / Q000032:analysis*; D013395:Sucrose / Q000494:pharmacology; D013997:Time Factors; D014089:Tooth Remineralization; D014508:Urea / Q000494:pharmacology
chemical_list: D002130:Calcium Phosphates; D002326:Cariogenic Agents; D002327:Cariostatic Agents; D002364:Caseins; D002614:Chelating Agents; D010710:Phosphates; C012980:fluorophosphate; D010758:Phosphorus; D013395:Sucrose; D014508:Urea; C020243:calcium phosphate; D005459:Fluorides; D002118:Calcium