In Vitro Evaluation of Enamel Microhardness Following at-Home Bleaching and Laser-Assisted in Office Bleaching

Ahrari, Farzaneh and Akbari, Majid and Hamzei, Haniye (2017) In Vitro Evaluation of Enamel Microhardness Following at-Home Bleaching and Laser-Assisted in Office Bleaching. Journal of Mashhad Dental School, 41 (1). pp. 1-10.

JMDS_Volume 41_Issue 1_Pages 79-82.pdf

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Introduction: Researchers have reported conflicting results in terms of the effects of tooth bleaching on mechanical properties of enamel. This study aimed to evaluate the effect of at-home bleaching and laser-assisted in-office bleaching on microhardness of enamel. Materials and Methods: In this experimental study, 18 healthy bovine incisors were selected and divided into two groups. Home-bleaching with 15 carbamide peroxide was applied for the first group for eight hours a day over 15 days. On the other hand, in-office bleaching was performed on the samples of the second group using 40 hydrogen peroxide and a GaAlAs diode laser (wavelength 810 nm), applied to accelerate tooth bleaching at settings of 2 W as a continuous wave in non-contact mode. This process was performed for three sessions over 15 days. Specimens were stored in Fusayama Meyer artificial saliva during the study. Vickers hardness test was performed to assess the microhardness of the specimens before and after bleaching in both groups. Data analysis was performed using paired and independent t-tests, and P-value of less than 0.05 was considered statistically significant. Results: While hardness of enamel decreased after both at-home bleaching and laser-assisted in-office bleaching, this reduction was not significant (P>0.05). No significant difference was observed between the study groups in terms of enamel hardness before and after the bleaching procedures (P>0.05). Conclusion: According to the results of this study, none of the bleaching methods had a significant impact on mineral properties of intact enamel. Therefore, both procedures could be recommended as conservative methods for treatment of discolored teeth.

Item Type: Article
Subjects: WU Dentistry. Oral surgery
Divisions: Journals > Journal of Mashhad Dental School
Depositing User: jmds jmds
Date Deposited: 20 Sep 2017 12:10
Last Modified: 20 Sep 2017 12:10

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