Evaluation of Relative Dentin Abrasivity in Whitening Toothpastes Containing Acids

Jae-Heon Kim; Vesna Miletic; Julian Gregoire Leprince; Young-Seok Park

doi:10.1016/j.identj.2024.04.004

Evaluation of Relative Dentin Abrasivity in Whitening Toothpastes Containing Acids

Int Dent J. 2024 May 17:S0020-6539(24)00111-4. doi: 10.1016/j.identj.2024.04.004. Online ahead of print.

Authors

Jae-Heon Kim¹, Vesna Miletic², Julian Gregoire Leprince³, Young-Seok Park⁴

Affiliations

¹ Department of Oral Anatomy and Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Republic of Korea.
² School of Dentistry, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia.
³ Division of Cariology and Endodontology, Section of Dental Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
⁴ Department of Oral Anatomy and Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Republic of Korea; Center for Future of Dentistry, School of Dentistry, Seoul National University, Seoul, Republic of Korea. Electronic address: ayoayo7@snu.ac.kr.

PMID: 38762371
DOI: 10.1016/j.identj.2024.04.004

Abstract

Introduction and aims: This study aimed to evaluate the relative dentin abrasivity of whitening toothpastes containing acids using the Radioactive Dentin Abrasivity - Profilometry Equivalent (RDA-PE).

Methods: A total of 100 bovine dentin specimens were prepared and assigned to the following groups (n = 10): 5 hydrogen peroxide (HP) whitening toothpastes (WTH1-WTH5) with or without acid (citric acid, ethylenedinitrilotetraacetic acid disodium, and phosphoric acid), 2 whitening toothpastes with silica and containing citric or phosphoric acid (WTS1 and WTS2), one conventional toothpaste (CT), and 2 reference slurries (RS). All specimens were brushed for 4,000 or 10,000 strokes using toothbrush and toothbrushing machine. The average dentin depth was measured using a noncontact profilometery, and the RDA-PE value was calculated based on the RS. The pH of the solution, average particle size, particle content, and particle hardness were measured. The RDA-PE data were analysed using one-way analysis of variance and Tukey's test, and the effects of the 4 measured factors on RDA-PE were investigated via multiple regression analysis.

Results: The RDA-PE values of the HP whitening toothpastes (mean value: 19-46) were significantly lower, whereas those of the silica whitening toothpastes (80 or 111) were similar to those of the RS after 4,000 strokes (100). The RDA-PE values of all whitening toothpastes were significantly lower than the RS values after 10,000 strokes (242). The HP whitening toothpastes were slightly acidic (pH ≤6) compared to the other solutions. The HP (2.9%-3.7%) and silica (8.9% or 9.9%) whitening toothpastes had significantly lower particle content than RS (16.6%). The particle content significantly influenced the RDA-PE values by multiple regression results.

Conclusions: The RDA-PE values of whitening toothpastes varied. The particle content in the solution was a key factor affecting the RDA-PE value.

Clinical relevance: Whitening toothpastes containing acids did not cause significant dentin abrasion.

Keywords: Acids; Hydrogen peroxide; Toothpaste particle; Whitening toothpaste; pH.