Tooth abrasivity laboratory studies as per ISO 11609, Annex B, to measure Relative Enamel Abrasivity (REA), Relative Dentine Abrasivity (RDA) and RDA Abrasivity Limit using profilometry to support oral care product development and marketing claims
Why is ISO 11609:2017 abrasivity testing important for oral care product development?
Understanding tooth abrasivity or tissue loss is a critical to determining any potential damage caused to enamel and dentine from oral care products such as toothpastes, tooth powders and even toothbrushes. The standard, ISO 11609:2017 Dentistry — Dentifrices — Requirements, test methods and marking, establishes methods for the determination of tooth abrasivity and applies to dentifrices such as toothpastes or powders, destined to be used by the consumers on a daily basis with a toothbrush to promote oral hygiene. Dentifrices should not cause any adverse reactions to the oral tissues when used in accordance with the manufacturer's recommendation for frequency and duration of use and consumer and market trends towards specialised stain removal and tooth whitening products in particular, has driven a growth in interest in tooth abrasivity. Overly abrasive formulations can contribute to enamel wear, dentine abrasion, tooth sensitivity, and damage to exposed root surfaces. Robust Relative Enamel Abrasivity (REA), Relative Dentine Abrasivity (RDA) and the RDA abrasivity limit testing quantifies the potential for dentifrice products to abrade dental hard tissue and this insight can support product development (e.g. formulation development) or marketing claims.
Novel dentifrice formulations are constantly being developed to address consumer needs, for example, for improved tooth whitening combined with low abrasivity or claims related to minimal enamel damage where it is important to balance cleaning efficacy with protection of tooth tissue. Demonstrating compliance with ISO 11609 can support your market access and acceptance by regulators, consumers and certification bodies. Additionally, understanding REA or RDA can help protect consumer safety, compare formulations (e.g. different abrasive agents such as silica, calcium carbonate or alumina) and support product quality and consistency.
What does REA, RDA and the RDA Abrasivity Limit testing as per ISO 11609 involve?
Samples of human / bovine enamel or dentine are typically prepared in resin discs and polished to expose a flat and perfectly smooth surface. The edges of the specimen are masked off leaving the area of interest exposed. This area of the surface is then brushed using a mechanical brushing machine and a slurry of the test dentifrice under specific conditions of load, speed and duration.
Annex B of the ISO standard covers the use of surface profilometry, either in two dimensions using a probe or in three dimensions using a laser scanner, to quantify the amount of tissue removed by the brushing process. At least six specimens are used for each test dentifrice and the mean depths are calculated. REA and RDA values are then calculated relative to a calcium pyrophosphate reference material as specified in ISO11609.
How can Intertek support your ISO 11609 testing needs for your novel dentifrices?
Our in vitro clinical research scientists conduct abrasivity and tissue loss studies (REA and RDA) using surface profilometry as described in Annex B ISO 11609 to support your product development process or claims substantiation.
We present tooth abrasivity and tissue loss study data in professional laboratory reports which, depending on our knowledge of the formulation, may include a detailed interpretation of the results. We are also happy to discuss how the insights from our studies can help you to improve formulations or to suggest bespoke brushing experiments that seek a deeper understanding of abrasivity and tissue loss. We also have the capacity to investigate other surface properties using, for example,
Scanning Electron Microscopy (SEM), Surface Microhardness (SMH), or a range of chromameters and gloss meters.
Why is Intertek CRS a leading ISO 11609:2017 abrasivity testing partner to support your oral care product development?
For over 20 years, our Clinical Research Services group has been a trusted partner for developers and manufacturers of oral care products. We bring quality and safety to life by providing a one source solution for all of your oral care in vitro studies with robust data supporting the efficacy and safety of novel treatments. We are ISO 9001 accredited, ensuring rigorous quality management across all our studies and also licensed under the Human Tissue Act 2004 to handle and store human tissue responsibly, following both the Act and local ethical guidelines. By working to the spirit of Good Laboratory Practice (GLP), we deliver reliable, reproducible results built on integrity, scientific rigor, and regulatory compliance.
Video: Surface Profilometry Studies for Tooth Abrasivity (REA and RDA)
We present tooth abrasivity and tissue loss study data in professional laboratory reports which, depending on our knowledge of the formulation, may include a detailed interpretation of the results. We are also happy to engage with the client on how to improve their formulations or to suggest bespoke brushing experiments that seek a deeper understanding of abrasivity and tissue loss. We also have the capacity to investigate other surface properties using, for example, Scanning Electron Microscopy (SEM), Surface Microhardness (SMH), or a range of chromameters and gloss meters.
For over 20 years, our Clinical Research Services group has been a trusted partner for developers and manufacturers of oral care products offering Total Quality Assurance. We bring quality and safety to life by providing a one source solution for all of your oral care in vitro studies providing robust data to support the efficacy and safety of novel treatments. These in vitro studies can provide valuable information to support your product development process.
Intertek Clinical Research Services (CRS) has a dedicated in vitro laboratory which conducts testing of all aspects of Oral Care products. We are particularly adept in designing bespoke in vitro models to cater for your specific requirements. Intertek Clinical Research Services is licensed to handle and store human tissue under the Human Tissue Act 2004 and follows the principles outlined within the act as well as complying with local ethical guidelines.
Our team of laboratory scientists have a combined experience of over 20 years of testing oral care products and contributed to a variety of scientific papers in collaboration with many well-known clients and have presented posters at International scientific conferences.
