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VOLUME 8 , ISSUE 1 ( January-February, 2017 ) > List of Articles

RESEARCH ARTICLE

Influence of the Number of Bleaching Sessions on Fracture Resistance and Dentin Microhardness of Endodontically Treated Teeth

Matheus Coelho Bandeca, Milton C Kuga, Keren CF Jordão-Basso, Mateus R Tonetto, Suellen L Lima, Lorena DMA Garrido, Natália G Kalatzis-Sousa, Andrea AR Dantas, Renato DT Leonardo

Citation Information : Bandeca MC, Kuga MC, Jordão-Basso KC, Tonetto MR, Lima SL, Garrido LD, Kalatzis-Sousa NG, Dantas AA, Leonardo RD. Influence of the Number of Bleaching Sessions on Fracture Resistance and Dentin Microhardness of Endodontically Treated Teeth. World J Dent 2017; 8 (1):5-9.

DOI: 10.5005/jp-journals-10015-1402

Published Online: 01-06-2013

Copyright Statement:  Copyright © 2017; The Author(s).


Abstract

Objectives

To evaluate the effects of number of bleaching sessions on fracture resistance and dentin microhardness in endodontically treated teeth using 15% hydrogen peroxide with titanium dioxide nanoparticles (15HPTiO2) associated to light emitting diode (LED)—laser system.

Materials and methods

Forty human incisors were endodontically treated and divided according to the number of bleaching sessions (n = 10, each group): G1 — no treatment G2 — one; G3 — two; and G4 — three sessions. The 15HPTiO2 was applied within the pulp chamber and on the buccal surface, then photoactivated using LED—laser. All experimental specimens were restored with ionomer glass cement between each session and in the final treatment. Specimens were then subjected to the fracture resistance test (kN), using an electromechanical machine. To the dentin microhardness evaluation, 40 crown extracted endodontically treated human teeth were longitudinally sectioned, divided into groups as previously described (n = 10), and submitted to similar bleaching protocol. Dentin microhardness was evaluated before and after the final dental bleaching session in each group using Knoop indentator. Data were analyzed by analysis of variance (ANOVA) and Tukey tests (p = 0.05).

Results

The fracture resistance values were similar among all groups (p > 0.05). The number of dental bleaching sessions had a negative influence on the microhardness dentin, because G4 > G3 > G2 > G1 (p < 0.05).

Conclusion

The number of bleaching sessions using 15% hydrogen peroxide with titanium dioxide nanoparticles associated to LED—laser system had no influence on the fracture resistance of the endodontically treated teeth crowns, but promoted a reduction in dentin microhardness.

How to cite this article

Garrido LDMA, Kuga MC, Kalatzis- Sousa NG, Dantas AAR, Tonetto MR, Leonardo RDT, Jordão- Basso KCF, Lima SL, Borges AH, Bandeca MC. Influence of the Number of Bleaching Sessions on Fracture Resistance and Dentin Microhardness of Endodontically Treated Teeth. World J Dent 2017;8(1):5-9.


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  1. Nonvital tooth bleaching: a review of the literature and clinical procedures. J Endod 2008 Apr;34(4):394-407.
  2. Coronal resistance to fracture of endodontically treated teeth submitted to lightactivated bleaching. J Dent 2008 Nov;36(11):935-939.
  3. Effect of internal bleaching agents on dentinal permeability of nonvital teeth: quantitative assessment. Dent Traumatol 2003 Apr;19(2):85-89.
  4. Effect of intracoronal bleaching agents on dentin microhardness. J Endod 2007 Apr;33(4):460-462.
  5. Effect of concentrated hydrogen peroxide solution on the surface morphology of cut human dentin. Endod Dent Traumatol 1988 Feb;4(1):32-36.
  6. Histochemical analysis of dental hard tissues following bleaching. J Endod 1996 Jan;22(1):23-25.
  7. Effect of hydrogen peroxide and sodium perborate on biomechanical properties of human dentin. J Endod 2002 Feb;28(2):62-67.
  8. Fracture resistance and failure pattern of teeth submitted to internal bleaching with 37% carbamide peroxide, with application of different restorative procedures. J Appl Oral Sci 2006 Aug;14(4):247-252.
  9. An evaluation of endodontically treated vertical root fractured teeth: impact of operative procedures. J Endod 2001 Jan;27(1):46-48.
  10. Development and evaluation of a method in vitro to study the effectiveness of tooth bleaching. J Dent 2003 Aug;31(6):415-422.
  11. Ex-vivo evaluation of the intrapulpal temperature variation and fracture strength in teeth subjected to different external bleaching protocols. Braz Dent J 2011;22(1):32-36.
  12. The bleaching of teeth: a review of the literature. J Dent 2006 Aug;34(7):412-419.
  13. Tooth discolouration and staining: a review of the literature. Br Dent J 2001 Mar 24;190(6):309-316.
  14. Effect of photochemical bleaching gel with and without TiO2 and different wavelengths. Braz J Oral Sci 2010;9:393-397.
  15. Effect of light-enhanced bleaching on in vitro surface and intrapulpal temperature rise. J Esthet Restor Dent 2001;13(6):370-378.
  16. Clareamento dental com fontes hibrida LED/laser. 2nd ed. São Paulo, Brazil: Santos; 2007. p. 9-15.
  17. Effects of light irradiation on bleaching by a 3.5% hydrogen peroxide solution containing titanium dioxide. Laser Phys Lett 2008 May;5(5):379-383.
  18. Comparative study of six rotary nickel-titanium systems and hand instrumentation for root canal preparation. Int Endod J 2005 Oct;38(10):743-752.
  19. Evaluation of fracture resistance of endodontically treated teeth restored with prefabricated posts and composites with varying quantities of remaining coronal tooth structure. J Appl Oral Sci 2005 Jun;13(2):141-146.
  20. Effects of light sources and visible lightactivated titanium dioxide photocatalyst on bleaching. Dent Mater J 2009 Nov;28(6):693-699.
  21. In situ study of in-office bleaching procedures using light sources on human enamel microhardness. Oper Dent 2010 Mar-Apr;35(2):139-146.
  22. Effects of direct and indirect bleach on dentin fracture toughness. J Dent Res 2007 Dec;86(12):1193-1197.
  23. Effect of traditional and alternative intracoronal bleaching agents on microhardness of human dentine. J Oral Rehabil 2004 Aug;31(8):811-816.
  24. Bleaching agents with varying concentrations of carbamide and/or hydrogen peroxides: effect on dental microhardness and roughness. J Esthet Restor Dent 2008;20(6):395-402.
  25. Effects of the hydroxyl radical and hydrogen peroxide on tooth bleaching. J Endod 2004 Jan;30(1):45-50.
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