title: Varnish or polymeric coating for the prevention of demineralization? An ex vivo study.
abstract: OBJECTIVE
  The ability of an experimental coating, Odyssey, to prevent demineralisation ex vivo was compared with that of a fluoride varnish, Duraphat and a chlorhexidine-containing varnish, Cervitec.
  
  
  METHODS
  an ex vivo single-blind study.
  
  
  METHODS
  Hard tissue research laboratory.
  
  
  METHODS
  thirty bovine enamel blocks 0.5 cm x 1.5 cm were divided into 6 groups of 5 specimens. The enamel blocks were then allocated to one of 6 surface treatments.
  
  
  METHODS
  (1) surface left unprepared (control), (2) Duraphat application, (3) Cervitec application, (4) experimental polymer coating, (5) enamel conditioned with 10% citric acid and coated with the experimental polymer coating Odyssey (O + C), (6) enamel etched for 30 sec with 37% phosphoric acid and coated with the experimental coating (O + E). All specimens were cycled for 7 days through a daily procedure of demineralisation for 4 hours and remineralisation for 20 hours, and exposed to an equivalent of 2 months toothbrushing. A single operator blinded to the treatment allocation of each specimen carried artificial lesion depth assessment out using computer-assisted transverse microradiography.
  
  
  RESULTS
  The control group had the greatest mean lesion depth (97.16 + 29.8 microm) with the Duraphat group exhibiting the lowest mean lesion depth (24.53 + 15.44 microm). The Duraphat, Odyssey, O + C and O + E groups all had significantly less lesion depth when compared with no surface preparation (p < 0.05 for all comparisons). There were no significant differences between any of the Odyssey groups.
  
  
  CONCLUSIONS
  The efficacy of Duraphat application in preventing demineralisation ex vivo has been demonstrated in the present study, but clinical trials are required to assess its usefulness in orthodontic practice.
authors.affiliation: Hard Tissue Research Group, University of Glasgow Dental School, Glasgow, UK.
authors.forename: T J
authors.initials: TJ
authors.lastname: Gillgrass
authors.forename: S L
authors.initials: SL
authors.lastname: Creanor
authors.forename: R H
authors.initials: RH
authors.lastname: Foye
authors.forename: D T
authors.initials: DT
authors.lastname: Millett
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000891:Anti-Infective Agents, Local / Q000627:therapeutic use; D002417:Cattle; D002710:Chlorhexidine / Q000627:therapeutic use*; D004338:Drug Combinations; D005460:Fluorides, Topical / Q000627:therapeutic use; D010150:Paint; D010895:Pit and Fissure Sealants / Q000627:therapeutic use*; D011108:Polymers / Q000627:therapeutic use; D016037:Single-Blind Method; D012969:Sodium Fluoride / Q000627:therapeutic use*; D018709:Statistics, Nonparametric; D013943:Thymol / Q000627:therapeutic use*; D017001:Tooth Demineralization / Q000517:prevention & control*
chemical_list: D000891:Anti-Infective Agents, Local; D004338:Drug Combinations; D005460:Fluorides, Topical; D010895:Pit and Fissure Sealants; D011108:Polymers; C079161:chlorhexidine, thymol drug combination; C023807:sodium fluoride topical preparation; D013943:Thymol; D012969:Sodium Fluoride; D002710:Chlorhexidine