Use of violet light in tooth whitening: study of efficacy whitener, tooth fluorescence, trans-dentinoenamel penetration H2O2, cytotoxicity, hydraulic conductance, heat generation and adhesion to resin materials
There are several types of bleaching treatments nowadays, associating with or without laser or LED lights, but these techniques have been associated with the patient complaints of sensitivity. In order to improve this discomfort researchers have proposed only one denteário bleaching source irradiating a violet LED, without the need of bleaching gel, but doubt about its efficiency and other qualities. So is the aim of this study was to evaluate this new treatment associated with different concentrations of H2O2 as their whitening efficacy, H2O2 penetration capacity by the tooth structure, the cytotoxicity of various protocols, as well as the permeability of the enamel and dentin, and also assess intrapulpal the temperature and the influence of treatments in adherence to resin materials. For both initially will be chosen 500 bovine teeth. Then these teeth will be distributed to the tests to be performed. After distributed teeth 10 result in the following groups: GI-control; IGI-PH 35%; GIII-PH 17.5%; GIV-LED / Laser; GV-PH 35% + LED / Laser; GVI-PH17,5% + LED / Laser; GVII-violet LED; GVIII + 35% PH-violet LED; GIX-PH 17.5% + violet LED. Bleaching treatments will be conducted in three sessions, with three 15-minute applications in each session, totaling 45 minutes of gel contact with the tooth per session. The groups receiving irradiation with light / laser irradiation is carried out 3 to 3 minutes each, the groups receiving the LED with violet irradiation, the specimens are irradiated for 20 times of 30s with intervals of 1 minute between each irradiation. After bleaching procedures are performed analyzes superficial and deep color change, fluorescence intensity, hydraulic conductance, H2O2 penetration capacity through the tooth structure, cytotoxicity by assessing the cell metabolism by the MTT test, to quantify the change in temperature intrapulpal and also the microtensile test to assess the tags forming ability after the treatments. After collecting the data, these will be submitted to statistical tests appropriate for each type of analysis.
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