title: The walking bleach procedure: an in vitro study to measure microleakage of five temporary sealing agents.
abstract: The purpose of this study was to compare the in vitro sealing capacity of five materials, each used as a temporary sealing agent for the walking bleach technique. All teeth received traditional biomechanical root canal instrumentation, after which the walking bleach agent was placed in the pulp chamber space. The occlusal access was sealed with one of five temporary materials: two hydraulic filling materials, a photoactivated resin composite, a zinc oxide-eugenol cement, and a zinc oxide phosphate cement with/without the placement of a piece of rubber sheet that was placed as a barrier to isolate filling material from the bleaching agent. All teeth were stored in a 1% solution of Alcian blue with thermal cycling stress. After 1 wk, they were sectioned longitudinally, and ranked by graded scores of 0 to 3, according to the degree of the dye penetration. Significantly less dye microleakage was observed in the two hydraulic materials than in the photoactivated resin. Both zinc oxide-eugenol and zinc phosphate cements showed a considerable amount of microleakage. There were no significant differences between the groups with and without a rubber sheet. Our data demonstrate that hydraulic filling materials provide the most favorable cavosurface seal when they are firmly packed into the cavity space to prevent microleakage.
authors.affiliation: Department of Periodontics and Endodontics, Tsurumi University School of Dental Medicine, Yokohama, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Hosoya
authors.forename: C F
authors.initials: CF
authors.lastname: Cox
authors.forename: T
authors.initials: T
authors.lastname: Arai
authors.forename: J
authors.initials: J
authors.lastname: Nakamura
mesh_terms: D000423:Alcian Blue; D000704:Analysis of Variance; D001881:Borates / Q000737:chemistry; D002133:Calcium Sulfate / Q000737:chemistry; D004396:Coloring Agents; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry; D003763:Dental Leakage / Q000145:classification* / Q000175:diagnosis; D003786:Dental Pulp Cavity / Q000187:drug effects; D003794:Dental Restoration, Temporary; D004338:Drug Combinations; D006801:Humans; D006861:Hydrogen Peroxide / Q000627:therapeutic use; D016877:Oxidants / Q000627:therapeutic use; D011109:Polymethacrylic Acids / Q000737:chemistry; D011145:Polyvinyls / Q000737:chemistry; D012387:Root Canal Filling Materials / Q000737:chemistry*; D018915:Root Canal Preparation / Q000295:instrumentation; D012408:Rubber; D018709:Statistics, Nonparametric; D013816:Thermodynamics; D014073:Tooth Bleaching / Q000379:methods*; D015034:Zinc Oxide / Q000737:chemistry; D015035:Zinc Oxide-Eugenol Cement / Q000737:chemistry; D015036:Zinc Phosphate Cement / Q000737:chemistry
chemical_list: D001881:Borates; D004396:Coloring Agents; D003738:Dental Cements; D004338:Drug Combinations; C072654:Fermit; D016877:Oxidants; D011109:Polymethacrylic Acids; D011145:Polyvinyls; D012387:Root Canal Filling Materials; D015035:Zinc Oxide-Eugenol Cement; C020872:Cavit; C077092:Eugedain; D015036:Zinc Phosphate Cement; D012408:Rubber; D006861:Hydrogen Peroxide; D000423:Alcian Blue; D015034:Zinc Oxide; D002133:Calcium Sulfate; C027707:sodium perborate