Development of a hydrogen peroxide bleaching agent with the addition of calcium polyphosphate nanoparticles and its effect on the whitening and mineralization of dental enamel

• Grant number: 19/20272-1
• Support Opportunities: Scholarships in Brazil - Doctorate
• Effective date (Start): October 01, 2020
• Effective date (End): October 31, 2023
• Field of knowledge: Health Sciences - Dentistry - Dental Clinics
• Principal Investigator: Debora Alves Nunes Leite Lima
• Grantee: Mariangela Ivette Guanipa Ortiz
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil
• Associated scholarship(s): 21/10175-9 - Enzymatically-driven biomineralization potential of an experimental bleaching gel containing calcium-polyphosphate particles(CaPP), BE.EP.DR

Abstract

Calcium Polyphosphate Nanoparticles (CaPPNP) have recently been developed by adjusting the Ca:P ratio and have demonstrate to be an amorphous source of calcium and phosphate that would be essential for mineralization of dental tissues. Tooth sensitivity, soft tissue irritation, and alteration of enamel surface are the most commonly described side effects of tooth bleaching, thus, its elimination or reduction has been the focus of many studies. It is considered that still there is a need for the development of bleaching systems with the highest bleaching effectiveness and minimal or no side effects. Thus, the present project proposes the addition of CaPPNP in the formulation of a high concentrated hydrogen peroxide (HP) remineralizing bleaching agent. This bleaching agent (HP-CaPPNP) would provide bioavailable calcium and phosphate ions, controlling mineral deposition on bleached enamel surfaces,improving the mechanical and morphological properties of these surfaces, without compromising its bleaching potential. For the development of this project its first chapter will consist on the formulation, evaluation and comparison of the experimental bleaching agent's H2O2 concentration by tritrimetric techniques, and the measurement of its cytotoxic potential by means of cell viability tests (MTT) according to ISO 10993 -5. The second chapter will examine and compare the bleaching potential of HP-CaPPNP by means of spectrophotometry (ΔE e ΔE00), as well as its effect on the morphological changes of the bleached tooth enamel surface, using roughness (Ra) and Scanning Electron Microscopy (SEM) tests and its effect on the bleached surface mineral loss with microhardness (KHN), X-ray spectrometry (EDX) and Raman spectroscopy (FT-Raman) tests. (AU)