title: Effect of two in-office whitening agents on the enamel surface in vivo: a morphological and non-contact profilometric study.
abstract: This study evaluated the morphological effects produced in vivo by two in-office bleaching agents on enamel surface roughness using a noncontact profilometric analysis of epoxy replicas. The null hypothesis tested was that there would be no difference in the micromorphology of the enamel surface during or after bleaching with two different bleaching agents. Eighteen subjects were selected and randomly assigned to two treatment groups (n=9). The tooth whitening materials tested were 38% hydrogen peroxide (HP) (Opalescence Xtra Boost) and 35% carbamide peroxide (CP) (Rembrandt Quik Start). The bleaching agents were applied in accordance with manufacturer protocols. The treatments were repeated four times at one-week intervals. High precision impressions of the upper right incisor were taken at baseline as the control (CTRL) and after each bleaching treatment (T0: first application, T1: second application at one week, T2: third application at two weeks and T3: fourth application at three weeks). Epoxy resin replicas were poured from impressions, and the surface roughness was analyzed by means of a non-contact profilometer (Talysurf CLI 1000). Epoxy replicas were then observed using SEM. All data were statistically analyzed using ANOVA and differences were determined with a t-test. No significant differences in surface roughness were found on enamel replicas using either 38% hydrogen peroxide or 35% carbamide peroxide in vivo. This in vivo study supports the null hypothesis that two in-office bleaching agents, with either a high concentration of hydrogen or carbamide peroxide, do not alter enamel surface roughness, even after multiple applications.
authors.affiliation: Department of Biomedicine, Division of Dental Sciences and Biomaterials, University of Trieste, Trieste, Italy. mcadenaro@fmc.units.it
authors.forename: Milena
authors.initials: M
authors.lastname: Cadenaro
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Breschi
authors.forename: Cesare
authors.initials: C
authors.lastname: Nucci
authors.forename: Francesca
authors.initials: F
authors.lastname: Antoniolli
authors.forename: Erika
authors.initials: E
authors.lastname: Visintini
authors.forename: Carlo
authors.initials: C
authors.lastname: Prati
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Matis
authors.forename: Roberto
authors.initials: R
authors.lastname: Di Lenarda
mesh_terms: D000134:Acid Etching, Dental; D000328:Adult; D000077463:Carbamide Peroxide; D003743:Dental Enamel / Q000187:drug effects* / Q000648:ultrastructure; D003764:Dental Materials / Q000494:pharmacology; D004338:Drug Combinations; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006861:Hydrogen Peroxide / Q000627:therapeutic use; D007180:Incisor / Q000187:drug effects / Q000648:ultrastructure; D008297:Male; D008855:Microscopy, Electron, Scanning; D008964:Molar, Third / Q000187:drug effects / Q000648:ultrastructure; D016877:Oxidants / Q000627:therapeutic use*; D010545:Peroxides / Q000627:therapeutic use; D010756:Phosphoric Acids / Q000494:pharmacology; D016628:Replica Techniques; D014073:Tooth Bleaching / Q000379:methods*; D014508:Urea / Q000031:analogs & derivatives / Q000627:therapeutic use
chemical_list: D003764:Dental Materials; D004338:Drug Combinations; D016877:Oxidants; D010545:Peroxides; D010756:Phosphoric Acids; D000077463:Carbamide Peroxide; D014508:Urea; D006861:Hydrogen Peroxide; C030242:phosphoric acid