title: Influence of extra- and intra-oral application of CPP-ACP and fluoride on re-hardening of eroded enamel.
abstract: OBJECTIVE
  This in-situ study aimed to investigate the potential of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) crème and fluoride mouth rinse to re-harden erosively softened enamel and to evaluate the influence of an intra-oral or extra-oral application.
  
  
  METHODS
  Ten volunteers performed five experimental series. Per series, four bovine enamel samples were extra-orally softened by immersion in Sprite light(®) (2 min) and subsequently worn intra-orally for 5 min in intra-oral appliances. Thereafter, samples were treated (3 min) with either 250 ppm AmF/SnF(2) solution (Meridol) (series 1 and 3) or CPP-ACP crème (Tooth Mousse) (series 2 and 4). Application of the substances was performed extra-orally (series 1 and 2) or intra-orally (series 3 and 4). Untreated specimens served as control (series 5). The appliances were worn for 4 h afterwards. Knoop microhardness (KHN) measurement was performed at baseline, after softening and after completing of the respective run. Data were statistically analyzed by ANOVA and Bonferroni/Dunn post-hoc test.
  
  
  RESULTS
  No significant difference in baseline microhardness was observed, while immersion in Sprite light reduced the microhardness significantly. Significant re-hardening after intra-oral exposure occurred in all series, but baseline microhardness was not achieved. Microhardness in series 2 was significantly higher than that in series 1 and 5. No significant differences in KHN were detected between series 3, 4 and 5. The re-hardening ΔKHN (final microhardness - microhardness after erosion) was not significant different in all five series.
  
  
  CONCLUSIONS
  Intra-oral application of CPP-ACP crème or fluoride solution provides no benefit regarding re-hardening of erosively softened enamel.
authors.affiliation: Clinic for Preventive Dentistry, Periodontology and Cariology University of Zurich, Zürich, Switzerland. florian.wegehaupt@zzm.uzh.ch
authors.forename: Florian J
authors.initials: FJ
authors.lastname: Wegehaupt
authors.forename: Tobias T
authors.initials: TT
authors.lastname: Tauböck
authors.forename: Angela
authors.initials: A
authors.lastname: Stillhard
authors.forename: Patrick R
authors.initials: PR
authors.lastname: Schmidlin
authors.forename: Thomas
authors.initials: T
authors.lastname: Attin
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000588:Amines / Q000008:administration & dosage; D000704:Analysis of Variance; D000818:Animals; D002327:Cariostatic Agents / Q000008:administration & dosage*; D002364:Caseins / Q000008:administration & dosage*; D002417:Cattle; D003743:Dental Enamel / Q000187:drug effects* / Q000473:pathology; D004338:Drug Combinations; D004359:Drug Therapy, Combination; D005260:Female; D006244:Hardness; D006801:Humans; D008297:Male; D012016:Reference Values; D014002:Tin Fluorides / Q000008:administration & dosage; D017001:Tooth Demineralization / Q000473:pathology / Q000517:prevention & control; D014077:Tooth Erosion / Q000188:drug therapy* / Q000473:pathology; D014089:Tooth Remineralization / Q000379:methods*; D014093:Tooth, Artificial; D055815:Young Adult
chemical_list: D000588:Amines; D002327:Cariostatic Agents; D002364:Caseins; D004338:Drug Combinations; D014002:Tin Fluorides; C447032:casein phosphopeptide-amorphous calcium phosphate nanocomplex; C059813:Meridol