15% hydrogen peroxide dental bleaching containing titanium dioxide doped by nitrogen (TiO2_N): Effects of exposure times and activation methods

• Grant number: 10/08873-5
• Support Opportunities: Regular Research Grants
• Duration: August 01, 2010 - July 31, 2012
• Field of knowledge: Health Sciences - Dentistry - Dental Clinics
• Principal Investigator: Osmir Batista de Oliveira Júnior
• Grantee: Osmir Batista de Oliveira Júnior
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Associated researchers: Alessandra Nara de Souza Rastelli ; Edson Alves de Campos ; Fernando Luis Esteban Florez ; Marcelo Ferrarezi de Andrade ; Tais Cruz Martinez

Abstract

Despite widely used, there are several doubts over the effectiveness of different bleaching agents, concentrations, protocols and light sources that are indicated to the in office dental bleaching. In this project it is intended to study the effectiveness of the heterogeneous oxidative process of a bleaching agent composed by hydrogen peroxide at 15% containing titanium dioxide doped by nitrogen as a semiconductor. It will be analyzed 90 bovine incisors slices distributed randomly within nine experimental groups (n=10), previously stained by immersion in Black Tea solution (Camelia Sinensis - Mate Leão - Brasil) during the period of 24 hours. The groups G1 to G4 will receive the bleaching agent and the photonic catalysis process, and the groups G5 to G8 will receive only the bleaching agent. The Group (control group) will receive the treatment as recommended by the manufacturer. It will be realized three clinical appointments simulations with a 7 days interval between each one programmed. In each simulation, it will be realized 3 applications of the bleaching agent over the slices surfaces by the experimental periods of 4(G1 and G5), 8(G2 and G6), 12(G3 and G7) and 16(G4 and G8) minutes. The effectiveness of the process will be analyzed in function of the samples shade reduction by two different methods: commercial spectrophotometer (Vita EasyShade - Vident) and a computational digital image processing (ScanWhite - Darwing System). The color acquisition moments are: before staining (M1), after staining (M2) and after each bleaching agent application as described elsewhere (M3 to M13). The longevity of the whitening obtained will be assessed at 7 (M14), 30(M15) and 180(M16). The effect of the exposure time and activation methods on the shade reduction obtained after each experimental condition will be determined by the E, L*, a* and b* (CIE 1976) values, by comparing the obtained scores for each color parameter of the samples with the Vita Classical color pallet (EasyShade) and by the total shade reduction (ScanWhite). The obtained results will be statistically treated and will be plot in self explicative graphics which will be compared in order to establish the most efficient protocol, the effectiveness curve, the longevity of the obtained aesthetic results and the reproducibility of the analytical methods used. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BORTOLATTO, J. F.; PRETEL, H.; FLOROS, M. C.; LUIZZI, A. C. C.; DANTAS, A. A. R.; FERNANDEZ, E.; MONCADA, G.; DE OLIVEIRA, JR., O. B.. Low Concentration H2O2/TiO_N in Office Bleaching: A Randomized Clinical Trial. JOURNAL OF DENTAL RESEARCH, v. 93, n. 7, 1, p. 66-71, JUL 2014. (10/08873-5)