Therapeutic potential evaluation of biosilicate gel against the oxidative stress of the pulp tissue due to dental bleaching and its influence on the penetration capacity of hydrogen peroxide and bleaching efficiency. in vivo and in vitro study

• Grant number: 16/23362-3
• Support Opportunities: Scholarships in Brazil - Master
• Start date: March 01, 2017
• End date: February 28, 2019
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Luciano Tavares Angelo Cintra
• Grantee: Marina Carminatti
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

In the previous study of the candidate (Process Fapesp nº 2015 / 22996-6, Carminatti et al., 2016ab) we observed that two protocols of application of Biosilicate gel presented positive results in minimizing of the damages caused to the pulp tissue after dental bleaching. However, it would be interesting to understand the mechanism of action of this product against oxidative stress and to evaluate if its use reduces the penetration of hydrogen peroxide (H2O2) towards the pulp tissue, however, without compromising the bleaching efficacy. Objective: To investigate the therapeutic potential of different Biosilicate® (BS) application protocols on the pulp of Wistar rat molars, to evaluate of the trans-enamel/dentin penetration of the H2O2 and, to evaluate the bleaching efficacy in bovine tooth blocks. Methods: In vivo segment: 40 hemi-maxillae of 20 rats will be randomly divided into 4 groups (n=10): Group- will not receive any treatment; BLE- will receive 30 min of the bleaching gel H2O2 35%; BS-BLE- will receive 20 min of BS gel, followed by 30 min of 35% H2O2; BLE+BS - will receive 30 min of a mixture of the 35% H2O2 with the BS gel. After 2 days, the animals will be killed and the hemi-maxilla processed for histological analysis in H.E. and immunohistochemistry (PCNA, HO-1, TNF-±,Substance P). The inflammation and immunolabeling for TNF-± and Substance P will be evaluated by scores, analyzed by the Kruskal Wallis and Dunn tests (P<.05). The immunolabelled cell count for PCNA and HO-1 will be submitted to the Shapiro-Wilk normality test to define the statistical test (P<.05). Segment in vitro: 40 discs of bovine teeth will be coupled in chambers and divided into 4 groups (n=10) that will receive the same treatments as the in vivo segment. The penetration of H2O2 by enamel and dentin will be quantified based on its reaction with the leukocrystal violet dye. The color change will be analyzed by the CIELab system, in the periods: before the bleaching session - (T0), immediately after (T1), and 24 hours after (T2). The data will be submitted to the Shapiro-Wilk normality test to define which statistical test will be used (P<.05). (AU)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

CARMINATTI, Marina. In vivo and in vitro evaluation of Biosilicate® against oxidative stress, hydrogen peroxide penetration and bleaching efficacy.. 2019. Master's Dissertation - Universidade Estadual Paulista (Unesp). Faculdade de Odontologia. Araçatuba Araçatuba.