Author(s): Leonardo, Renato de Toledo [UNESP] ; Kuga, Milton Carlos [UNESP] ; Guiotti, Flavia Angelica [UNESP] ; Andolfatto, Carolina [UNESP] ; Faria-Junior, Norberto Batista de ; Campos, Edson Alves de [UNESP] ; Keine, Katia Cristina [UNESP] ; Dantas, Andrea Abi Rached [UNESP]
Date: 2015
Persistent ID: http://hdl.handle.net/11449/125888
Origin: Oasisbr
Subject(s): Nanoparticles; Peroxides; Tooth bleaching
Made available in DSpace on 2015-08-06T16:13:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2014
Made available in DSpace on 2015-08-06T16:13:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2014
Made available in DSpace on 2015-08-06T16:13:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2014
Aim: The aim of this study was to evaluate the fracture resistance of teeth submitted to several internal bleaching protocols using 35% hydrogen peroxide (35HP), 37% carbamide peroxide (37CP), 15% hydrogen peroxide with titanium dioxide nanoparticles (15HPTiO2) photoactivated by LED-laser or sodium perborate (SP). Materials and methods: After endodontic treatment, fifty bovine extracted teeth were divided into five groups (n = 10): G1-unbleached; G2-35HP; G3-37CP; G4-15HPTiO2 photoactivated by LED-laser and G5-SP. In the G2 and G4, the bleaching protocol was applied in 4 sessions, with 7 days intervals between each session. In the G3 and G5, the materials were kept in the pulp teeth for 21 days, but replaced every 7 days. After 21 days, the teeth were subjected to compressive load at a cross head speed of 0.5 mm/min, applied at 135° to the long axis of the root using an eletromechanical testing machine, until teeth fracture. The data were submitted to ANOVA and Tukey tests (α = 5%). Results: The 35HP, 37CP, 15HPTiO2 and SP showed similar fracture resistance teeth reduction (p > 0.05). All bleaching treatments reduced the fracture resistance compared to unbleached teeth (p < 0.05). Conclusion: All bleaching protocols reduced the fracture resistance of endodontically-treated teeth, but there were no differences between each other. Clinical significance: There are several internal bleaching protocols using hydrogen peroxide in different concentrations and activation methods. This study evaluated its effects on fracture resistance in endodontically-treated teeth.
Universidade Federal do Rio Grande do Norte, Departamento de Odontologia
Universidade Estadual Paulista Júlio de Mesquita Filho, Departamento de Odontologia Restauradora, Faculdade de Odontologia de Araraquara
