title: Sealing ability of two intermediate restorative materials in bleached teeth.
abstract: This study compared the radicular penetration of bleaching agents in endodontically treated teeth containing an IRM base, a Cavit base, and no base. Forty-five extracted human maxillary central incisors treated with conventional endodontic therapy with laterally condensed gutta percha and sealer were randomly divided into three groups: (1) Cavit base, (2) IRM base and (3) no base. In groups 1 and 2, a 3.5 mm thickness of base material was placed at the time of obturation. After storage in saline for 1 week, the teeth were bleached with a mixture of 35% hydrogen peroxide and sodium perborate, combined with a 10% methylene blue dye solution, using a combination thermocatalytic and non-thermocatalytic bleaching technique. The apical distance of dye penetration was measured. The control group demonstrated dye penetration to the apex, indicating that a base is required to prevent leakage of bleaching agents when this combination of bleaching techniques is used. The mean distance of leakage was 3.43 mm (+/- 1.14) for the Cavit group and 5.94 mm (+/- 1.72) for the IRM group. Analysis with a t-test revealed that Cavit was a more effective barrier to leakage than IRM (T = 4.20, P less than 0.001).
authors.forename: J
authors.initials: J
authors.lastname: Hansen-Bayless
authors.forename: R
authors.initials: R
authors.lastname: Davis
mesh_terms: D001881:Borates / Q000009:adverse effects; D002133:Calcium Sulfate; D003736:Dental Cavity Lining; D003738:Dental Cements; D003763:Dental Leakage / Q000209:etiology*; D004338:Drug Combinations; D006171:Gutta-Percha; D006358:Hot Temperature; D006801:Humans; D006861:Hydrogen Peroxide / Q000009:adverse effects; D007180:Incisor; D008768:Methylmethacrylates; D011145:Polyvinyls; D012390:Root Canal Therapy; D014073:Tooth Bleaching / Q000009:adverse effects*; D015034:Zinc Oxide; D015035:Zinc Oxide-Eugenol Cement
chemical_list: D001881:Borates; D003738:Dental Cements; D004338:Drug Combinations; D008768:Methylmethacrylates; D011145:Polyvinyls; D015035:Zinc Oxide-Eugenol Cement; C031667:IRM cement; C020872:Cavit; D006171:Gutta-Percha; D006861:Hydrogen Peroxide; D015034:Zinc Oxide; D002133:Calcium Sulfate; C027707:sodium perborate