title: Comparison of Nd:YAG and diode laser irradiation during intracoronal bleaching with sodium perborate: color and Raman spectroscopy analysis.
abstract: OBJECTIVE
  The aim of this study was to evaluate the color and enamel structure changes after intracoronal bleaching with sodium perborate under neodymium:yttrium-aluminum-garnet (Nd:YAG) and diode laser irradiation.
  
  
  BACKGROUND
  Although some studies investigated the efficacy of laser irradiation during intracoronal bleaching, no study has been conducted to investigate the changes in both color and enamel structure during intracoronal bleaching with laser irradiation.
  
  
  METHODS
  Thirty-six extracted mandibular incisors were used. The root canals were prepared and filled with AH Plus and gutta-percha. Baseline color values and Raman spectra were obtained from all samples. The samples were randomly divided into three groups as follows: group 1, intracoronal bleaching with sodium perborate plus NdYAG laser irradiation; group 2, intracoronal bleaching with sodium perborate plus diode laser irradiation; and group 3, intracoronal bleaching with sodium perborate without any laser irradiation. Following the bleaching procedures, the final baseline color values and Raman spectra were obtained. The baseline and final values were statistically analyzed. Statistical analyses were performed with SPSS 18.0 software using Anova and the Kruskal-Wallis test.
  
  
  RESULTS
  There was a significant difference between the Nd:YAG laser and control groups (p<0.05). There was no significant difference between the diode laser group and the control group, or the diode laser group and the Nd:YAG laser group. There was no significant difference among all groups in terms of Raman relative intensity (RRI) and fluorescence intensity (FI) percentage values (p>0.05).
  
  
  CONCLUSIONS
  Laser application, especially Nd:YAG laser irradiation, was able to increase the efficacy of intracoronal bleaching with sodium perborate. Laser irradiation significantly increased the bleaching efficacy without any changes in the enamel surface structure.
authors: 1 Faculty of Dentistry, Department of Endodontics, Bülent Ecevit University , Zonguldak, Turkey .
authors: Baran Can
authors: BC
authors: Sağlam
authors: Mustafa Murat
authors: MM
authors: Koçak
authors: Sibel
authors: S
authors: Koçak
authors: Sevinç Aktemur
authors: SA
authors: Türker
authors: Dilara
authors: D
authors: Arslan
mesh_terms: D001881:Borates; D003743:Dental Enamel / Q000187:drug effects / Q000528:radiation effects*; D006801:Humans; D054023:Lasers, Semiconductor; D053844:Lasers, Solid-State; D028022:Low-Level Light Therapy; D013059:Spectrum Analysis, Raman; D046509:Tissue Culture Techniques; D014073:Tooth Bleaching
chemical_list: D001881:Borates; C027707:sodium perborate