1 Department of Operative Dentistry, Shahed University, Tehran, Iran
2 Laser Research Center of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
3 Department of Operative Dentistry, Tehran University of Medical Sciences, Tehran, Iran
Tooth restoration immediately after
bleaching is challenging due to the potential problems in achieving
adequate bond strength.
The aim of this study was to evaluate the effect of surface treatment with ER:YAG, ND:YAG, CO2 lasers and
10% sodium ascorbate solution on immediate microtensile bond strength of composite resin to recently bleached enamel.
Materials & Methods:
Ninety sound molar teeth were randomly divided into three main groups (n:30) : NB (without bleaching), HB (bleached with 38% carbamide peroxide)
and OB (bleached with Heydent bleaching gel assisted by diode laser). Each group was divided into five subgroups (n:6) : Si (without surface treatment),
Er (Er:YAG laser), CO2 (CO2 laser), Nd (Nd:YAG laser) and As (Immersion in 10% sodium ascorbate solution). The bonding system was then applied and
composite build-ups were constructed. The teeth were sectioned by low speed saw to obtain enamel- resin sticks and submitted to microtensile bond testing.
Statistical analyses were done using two- way ANOVA, Tukey and Tamhane tests.
µTBS of bleached teeth irradiated with ND:YAG laser was not
significantly different from NB-Nd group. Microtensile bond strength of OB-Er group was higher than NB-Er and HB-Er groups. The mean µTBS of HB-CO2
group was higher than NB-CO2 group; the average µTBS of HB-As and OB-As groups was also higher than NB-As group.
Use of Nd:YAG, CO2 lasers
and 10% sodium ascorbate solution could improve the bond strength in home-bleached specimens. Application of ND:YAG laser on nonbleached specimens
and Er:YAG laser on office-bleached specimens led to the highest µTBS in comparison to other surface treatments in each main group.
Keywords: Bleaching, CO2 laser, Er:YAG laser, microtensile bond strength, Nd:YAG laser, sodium ascorbate.
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(https://creativecommons.org/licenses/by-nc/4.0/legalcode), which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the
work is properly cited.
* Address correspondence to this author at the Department of Operative Dentistry, Tehran University of Medical Sciences, Tehran, Iran;
Tel: +982188015017; Fax: +982188015017;