Piezo-catalysis for nondestructive tooth whitening

Yang Wang,Yunyang Bai,Xinrong Wen,Guoliang Yuan,Xuehui Zhang,Yanmin Jia,Feifei Wang,Yaojin Wang,Ming Huang

doi:10.1038/s41467-020-15015-3

Abstract

The increasing demand for a whiter smile has resulted in an increased popularity for tooth whitening procedures. The most classic hydrogen peroxide-based whitening agents are effective, but can lead to enamel demineralization, gingival irritation, or cytotoxicity. Furthermore, these techniques are excessively time-consuming. Here, we report a nondestructive, harmless and convenient tooth whitening strategy based on a piezo-catalysis effect realized by replacement of abrasives traditionally used in toothpaste with piezoelectric particles. Degradation of organic dyes via piezo-catalysis of BaTiO3 (BTO) nanoparticles was performed under ultrasonic vibration to simulate daily tooth brushing. Teeth stained with black tea, blueberry juice, wine or a combination thereof can be notably whitened by the poled BTO turbid liquid after vibration for 3 h. A similar treatment using unpoled or cubic BTO show negligible tooth whitening effect. Furthermore, the BTO nanoparticle-based piezo-catalysis tooth whitening procedure exhibits remarkably less damage to both enamel and biological cells.

Highlights

The increasing demand for a whiter smile has resulted in an increased popularity for tooth whitening procedures
Since electrical charges can be induced by mechanical vibration, piezoelectric materials have been employed as catalysers, termed as piezo-catalysis or mechano-catalysis[27,28]
In view of notable mechanical vibration during our daily tooth brush procedure (Fig. 1a), and nano-sized abrasive particles in toothpaste (Fig. 1b), we propose a nondestructive and safe tooth whitening strategy based on the piezo-catalysis effect, realized by replacement of abrasives with piezoelectric nanoparticles

Summary

Introduction

The increasing demand for a whiter smile has resulted in an increased popularity for tooth whitening procedures. The most classic hydrogen peroxide-based whitening agents are effective, but can lead to enamel demineralization, gingival irritation, or cytotoxicity In order to gain a confident smile, there are several common methods for tooth whitening, such as professional cleaning and polishing, coverage with crowns or veneers, daily toothbrushing with abrasive toothpaste, and bleaching[3] Both professional procedural cleaning and coverings require grinding or other enamelcutting steps, which cause irreversible damage. The mechanism of hydrogen peroxide for tooth whitening is the release of unstable, reactive oxygen species during decomposition into water[9], which will attack organic pigment molecules on the surface of teeth, and degrade staining compounds by oxidation[3] This mechanism suggests that a material with the capability to excite and release reactive oxygen species could be effective as a tooth whitening agent. Some classical piezoelectric materials, such as ZnO29, BaTiO330,31, and BiFeO332, have been demonstrated as effecient piezo-catalysts

Methods

Results

Conclusion