title: The relationship of hydrogen peroxide exposure protocol to bleaching efficacy.
abstract: The purpose of this study was to compare two in-office bleaching methods with respect to tooth color change and level of hydrogen peroxide penetration into the pulp cavity and to evaluate relationships between penetration level and color change. Eighty extracted canines were exposed to two different bleaching regimens (conventional vs sealed bleaching technique). After exposure to 38% hydrogen peroxide gel for one hour, hydrogen peroxide amount was estimated spectrophotometrically. Color change was measured per Commission Internationale de l'Eclairage methodology. Linear regression was used to evaluate factors affecting color change, including bleaching technique. The conventional and sealed bleaching groups showed no difference for any color change parameters (ΔL, Δa, Δb, ΔE); however, there was significantly greater hydrogen peroxide penetration in the conventional bleaching group (p<0.05). Linear modeling of the change in lightness (ΔL) showed that the increase in lightness tended to be greater for teeth with lower initial L* values (r=-0.32, p<0.05). After adjustment for initial L*, there was no evidence that ΔL differed with hydrogen peroxide penetration levels (p>0.05) or bleaching technique (mean group difference in ΔL=0.36; p>0.05).
authors: Loma Linda University School of Dentistry, Loma Linda, CA, USA. sorankwon@llu.edu
authors: S R
authors: SR
authors: Kwon
authors: P W
authors: PW
authors: Wertz
authors: D V
authors: DV
authors: Dawson
authors: D S
authors: DS
authors: Cobb
authors: G
authors: G
authors: Denehy
mesh_terms: D003116:Color; D003481:Cuspid / Q000187:drug effects / Q000378:metabolism; D003786:Dental Pulp Cavity / Q000187:drug effects / Q000378:metabolism; D005456:Fluorescent Dyes; D005840:Gentian Violet; D006801:Humans; D006813:Humidity; D006861:Hydrogen Peroxide / Q000008:administration & dosage* / Q000493:pharmacokinetics; D008422:Materials Testing; D020959:Polyethylene / Q000737:chemistry; D013053:Spectrophotometry; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature; D013997:Time Factors; D014073:Tooth Bleaching / Q000295:instrumentation / Q000379:methods*; D058205:Tooth Bleaching Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics
chemical_list: D005456:Fluorescent Dyes; D058205:Tooth Bleaching Agents; C475159:leucocrystal violet; D020959:Polyethylene; D006861:Hydrogen Peroxide; D005840:Gentian Violet