title: Sealing evaluation of the cervical base in intracoronal bleaching.
abstract: Discoloration of non-vital teeth is an esthetic deficiency frequently requiring bleaching treatment. The purpose of this study was to evaluate in vitro the cervical base efficacy in order to prevent or to minimize the leakage along the root canal filling and into the dentinal tubules. Thirty-eight extracted single-root human teeth were used, which were biomechanically prepared, filled, and divided into three experimental groups: G1, a cervical base was applied (3 mm of thickness) below the cemento-enamel junction, with resin-modified glass-ionomer cement (Vitremer); G2, the base was done with glass-ionomer cement (Vidrion R); and G3 (Control), did not receive any material as base. A mixture of sodium perborate and hydrogen peroxide 30% was placed inside the pulp chamber for 3 days, and the access opening was sealed with Cimpat. This procedure was repeated thrice. Soon after this, a paste of calcium hydroxide was inserted into the pulp chamber for 14 days. All teeth were covered with two layers of sticky wax, except the access opening, and immersed in blue India Ink for 5 days. The results did not show statistically significant differences between the three groups concerning the leakage inside the dentinal tubules. Regarding the apical direction, a statistical difference (ANOVA P < 0.05) was observed among the experimental group G1 and control group G3. No statistically significant difference was observed between G2 and G3 groups. Therefore, the placement of a cervical base before internal bleaching procedures is still recommended.
authors.affiliation: Department of Bioscience and Diagnosis, School of Dentistry, Paulista State University-UNESP, São José dos Campos, São Paulo, SP, Brazil.
authors.forename: Luciane Dias
authors.initials: LD
authors.lastname: de Oliveira
authors.forename: Claudio Antonio Talge
authors.initials: CA
authors.lastname: Carvalho
authors.forename: Edson
authors.initials: E
authors.lastname: Hilgert
authors.forename: Ilda Ribeiro
authors.initials: IR
authors.lastname: Bondioli
authors.forename: Maria Amélia Máximo
authors.initials: MA
authors.lastname: de Araújo
authors.forename: Marcia Carneiro
authors.initials: MC
authors.lastname: Valera
mesh_terms: D000704:Analysis of Variance; D001881:Borates / Q000627:therapeutic use; D002126:Calcium Hydroxide / Q000627:therapeutic use; D003738:Dental Cements / Q000627:therapeutic use; D003763:Dental Leakage / Q000517:prevention & control*; D003786:Dental Pulp Cavity / Q000187:drug effects; D003806:Dentin Permeability / Q000187:drug effects*; D005899:Glass Ionomer Cements / Q000627:therapeutic use; D006801:Humans; D006861:Hydrogen Peroxide / Q000627:therapeutic use; D066298:In Vitro Techniques; D019279:Resin Cements / Q000627:therapeutic use; D012387:Root Canal Filling Materials / Q000627:therapeutic use*; D012390:Root Canal Therapy / Q000009:adverse effects; D014073:Tooth Bleaching / Q000379:methods*; D019237:Tooth Cervix / Q000187:drug effects*; D014075:Tooth Discoloration / Q000209:etiology / Q000628:therapy*; D019553:Tooth, Nonvital / Q000628:therapy
chemical_list: D001881:Borates; D003738:Dental Cements; D005899:Glass Ionomer Cements; D019279:Resin Cements; D012387:Root Canal Filling Materials; D006861:Hydrogen Peroxide; D002126:Calcium Hydroxide; C027707:sodium perborate