Antimicrobial performance of commercial antiplaque/antigingivitis formulations

Title : Antimicrobial performance of commercial antiplaque/antigingivitis formulations

Abstract:

Introduced at least as early as 1995, plaque growth and regrowth methods (PGRM) are sometimes used to assess the potential efficacy of antimicrobial oral care formulations. In fact, PGRM models are recognized as an evaluation tool by the US FDA for products comprising cetylpyridinium chloride (CPC) and stannous fluoride (SnF₂). These models, which may vary in design, typically assess plaque regrowth or glycolysis responses, or even plaque biofilm formation, when microbial species are exposed to the putative treatment. We recently introduced a glycolysis and automated plaque regrowth (GAPR) model that demonstrates sensitivity to a range of putative antimicrobial agents (Karlinsey & Karlinsey. Dent. J. 2024, 12(5), 146; https://doi.org/10.3390/dj12050146). In addition to bespoke recipes that assess microbial regrowth or glycolysis, the GAPR method utilizes harvested human plaque, which contrasts with the typical monospecies minimal inhibitory concentration (MIC) and kill-time (KT) evaluations. Despite the use of MIC and KT in ingredient/formulation screening, sometimes these evaluations conflict with other similar assays or do not mirror clinical outcomes. Using the GAPR method was a possible screening tool to help bridge the lab-clinic divide, in this presentation we provide background and methodology, as well as share some results when we applied our model to various commercial dentifrice and mouthwash products, including those with antiplaque benefits that lack formally recognized antimicrobial agents such as CPC or SnF₂.

Audience Take Away Notes:

• To introduce the audience to PGRM models in the evaluation of antiplaque/antigingivitis agents.
• To describe the sensitivity of the microbial recipes to growth and glycolysis.
• To provide information about a novel PGRM screening tool in the evaluation of putative ingredients/formulations.
• To share results from commercially available dental products that may improve understanding of how the formulation may promote antiplaque/antigingivitis benefits.

Biography:

Dr. Robert L. Karlinsey is a scientist and formulator with almost 20 years’ experience in dental research. He earned a BS in Physics (University of Scranton) and PhD in Chemical Physics (Indiana University), with postdoctoral work in physical chemistry (Indiana University). As a visiting assistant research professor at the Indiana University School of Dentistry, his research led to an impactful encounter with Dr. George Stookey, and shortly thereafter, the formation of Indiana Nanotech, LLC (now known as Custom Dental Formulations, LLC), of which he spearheaded all research and small-scale manufacturing efforts. Dr. Karlinsey is the inventor of Nanotech’s functionalized tricalcium phosphate systems, which continue to help generate over $100MM in global product sales for a major dental manufacturer.  As Principal Investigator, his work has received significant funding through Federal (National Institutes of Health), State (Indiana and Texas), and industry grants and contracts. His research in patented calcium phosphate technologies continue to help generate over $100MM in global product sales. Previously, Dr. Karlinsey has served as Chief Scientific Officer at Therametric Technologies, Inc, and adjunct professor of chemistry at the University of Indianapolis. Dr. Karlinsey addresses clients’ needs in preventive and cosmetic dentistry, including fluoride- and fluoride-free remineralization, antiplaque/gum health, whitening systems, and more. He is actively involved in clinical and laboratory research designs and performance-backed, customized oral care formulation solutions. And, whenever possible, he favors natural, nature-derived, and/or sustainably sourced ingredients.