title: Effect of fluoridated bleaching gels on the remineralization of predemineralized bovine enamel in vitro.
abstract: OBJECTIVE
  This study evaluated possible differences regarding the remineralization of predemineralized enamel after exposure to fluoridated or non-fluoridated bleaching gels.
  
  
  METHODS
  120 enamel specimens were prepared from sixty bovine incisors; before and after demineralization (37 degrees C; pH 4.95; 10d), one-quarter of each specimen's surface was covered with nail varnish (control sound/demineralized). Subsequently, the specimens were stored for 16h daily in a remineralizing solution (pH 7.0; 14d), while for the remaining time (8h) various bleaching gels were applied: (1) no treatment (control), (2) Opalescence regular (O, Ultradent), (3) Opalescence PF (O-PF), (4) Nite White ACP (NW-ACP, Discus Dental) and (5) Nite White ACPF (NW-ACPF). Following, half of the bleached parts were nail-varnished and stored for another 3-weeks period in a remineralizing solution. Differences in mineral losses (DeltaDeltaZ) and lesion depths (DeltaLD) before and after treatment/remineralization period were evaluated from microradiographs. DeltaDeltaZ(surface) values (mineral loss of the outer 18microm of the lesion) were calculated.
  
  
  RESULTS
  After 2 and 5 weeks DeltaDeltaZ/DeltaLD values of the bleaching groups did not differ significantly from the controls. Treatment with NW-ACPF for 2 weeks resulted in significantly lower DeltaDeltaZ values compared to NW-ACP (p=0.032) and NW-ACPF in higher values than Opalescence regular (p=0.006). Two weeks treatment with O and O-PF resulted in decreased DeltaDeltaZ(surface) values compared to control (p<0.0005), whereas with NW-ACPF no significant differences could be observed (p=0.062). Application of NW-ACP induced significantly increased DeltaDeltaZ(surface) values compared to control (p=0.001).
  
  
  CONCLUSIONS
  No supporting influence of fluoride-containing bleaching gels on remineralization could be observed.
authors.affiliation: Department of Operative Dentistry and Periodontology, University School of Dental Medicine, CharitéCentrum 3, Germany. peter.tschoppe@charite.de
authors.forename: Peter
authors.initials: P
authors.lastname: Tschoppe
authors.forename: Konrad
authors.initials: K
authors.lastname: Neumann
authors.forename: Jan
authors.initials: J
authors.lastname: Mueller
authors.forename: Andrej M
authors.initials: AM
authors.lastname: Kielbassa
mesh_terms: D000818:Animals; D002130:Calcium Phosphates / Q000008:administration & dosage / Q000627:therapeutic use; D000077463:Carbamide Peroxide; D002327:Cariostatic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D002417:Cattle; D003743:Dental Enamel / Q000187:drug effects* / Q000473:pathology; D004338:Drug Combinations; D005459:Fluorides / Q000008:administration & dosage / Q000627:therapeutic use*; D006813:Humidity; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D008852:Microradiography; D008903:Minerals / Q000032:analysis; D016877:Oxidants / Q000008:administration & dosage / Q000627:therapeutic use*; D010545:Peroxides / Q000008:administration & dosage / Q000627:therapeutic use; D011897:Random Allocation; D013696:Temperature; D013997:Time Factors; D014073:Tooth Bleaching / Q000379:methods*; D017001:Tooth Demineralization / Q000188:drug therapy* / Q000473:pathology; D014089:Tooth Remineralization; D014508:Urea / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000627:therapeutic use
chemical_list: D002130:Calcium Phosphates; D002327:Cariostatic Agents; D004338:Drug Combinations; D008903:Minerals; D016877:Oxidants; D010545:Peroxides; C519480:amorphous calcium phosphate; D000077463:Carbamide Peroxide; D014508:Urea; D005459:Fluorides