title: Re- and Demineralization Characteristics of Enamel Depending on Baseline Mineral Loss and Lesion Depth in situ.
abstract: The aim of this double-blinded, randomized, cross-over in situ study was to evaluate the re- and demineralization characteristics of sound enamel as well as lowly and highly demineralized caries-like enamel lesions after the application of different fluoride compounds.
  
  
  
  In each of three experimental legs of 4 weeks, 21 participants wore intraoral mandibular appliances containing 4 bovine enamel specimens (2 lowly and 2 highly demineralized). Each specimen included one sound enamel and either one lowly demineralized (7 days, pH 4.95) or one highly demineralized (21 days, pH 4.95) lesion, and was positioned 1 mm below the acrylic under a plastic mesh. The three randomly allocated treatments (application only) included the following dentifrices: (1) 1,100 ppm F as NaF, (2) 1,100 ppm F as SnF2 and (3) 0 ppm F (fluoride-free) as negative control. Differences in integrated mineral loss (x0394;x0394;Z) and lesion depth (x0394;LD) were calculated between values before and after the in situ period using transversal microradiography.
  
  
  
  Of the 21 participants, 6 did not complete the study and 2 were excluded due to protocol violation. Irrespectively of the treatment, higher baseline mineral loss and lesion depth led to a less pronounced change in mineral loss and lesion depth. Except for x0394;x0394;Z of the dentifrice with 0 ppm F, sound surfaces showed significantly higher x0394;x0394;Z and x0394;LD values compared with lowly and highly demineralized lesions (p < 0.05, t test).
  
  
  
  Re- and demineralization characteristics of enamel depended directly on baseline mineral loss and lesion depth. Treatment groups should therefore be well balanced with respect to baseline mineral loss and lesion depth.
authors.affiliation: Department of Operative Dentistry, Periodontology and Preventive Dentistry, RWTH Aachen University, Aachen, Germany.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Wierichs
authors.forename: Julian
authors.initials: J
authors.lastname: Lausch
authors.forename: Hendrik
authors.initials: H
authors.lastname: Meyer-Lueckel
authors.forename: Marcella
authors.initials: M
authors.lastname: Esteves-Oliveira
mesh_terms: D000328:Adult; D000818:Animals; D015519:Bone Density; D002417:Cattle; D018592:Cross-Over Studies; D003731:Dental Caries / Q000473:pathology / Q000628:therapy*; D003743:Dental Enamel / Q000473:pathology*; D003804:Dentin / Q000473:pathology; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008852:Microradiography; D008875:Middle Aged; D012969:Sodium Fluoride / Q000008:administration & dosage / Q000494:pharmacology; D013997:Time Factors; D014002:Tin Fluorides / Q000008:administration & dosage / Q000494:pharmacology; D017001:Tooth Demineralization / Q000473:pathology / Q000517:prevention & control*; D014089:Tooth Remineralization; D014100:Toothpastes / Q000008:administration & dosage* / Q000494:pharmacology; D055815:Young Adult
chemical_list: D014002:Tin Fluorides; D014100:Toothpastes; D012969:Sodium Fluoride