Development of an integrated dental plaque bioanalytical platform for point-of-care diagnostics of oral diseases

The National Institute of Dental and Craniofacial Research (NIDCR) awarded Oregon State University a $422,665 Project Grant on June 17, 2025, under the Oral Diseases and Disorders Research program (CFDA 93.121) to develop an integrated dental plaque bioanalytical platform for point-of-care diagnostics of oral diseases. The research addresses the significant financial burden of dental caries by creating a quantitative electrochemical biosensing platform capable of detecting and quantifying metabolites—specifically hydrogen peroxide (H2O2) and lactic acid—produced by dental plaque samples. The platform utilizes microliter volume droplet hydrogel electrochemical cells to analyze picomole quantities of metabolites produced by varying ratios of bacterial species, with the objective of establishing threshold values that distinguish non-caries from early caries conditions.

The two-year project, concluding June 16, 2027, is structured around two primary research aims: (1) detecting and quantifying H2O2 and lactate produced by different ratios of beneficial bacteria (Streptococcus sanguinis) and pathogenic bacteria (Streptococcus mutans), and (2) establishing correlations between oral caries conditions and untreated dental plaque metabolic activity, including investigation of time-dependent metabolic responses to various sugars such as glucose and sucrose. This research supports NIDCR's mission to advance prevention and early detection strategies for oral health conditions through translational research innovations applicable to clinical practice.

Abstract

Dental caries poses a significant financial burden to the oral healthcare system in the US. Hence, early detection and preventive measures for primary caries are essential for reducing treatment costs. IT is well-established that biofilm metabolic activity (lactic acid production) in the oral cavity, particularly close to the teeth, plays a pivotal role in the progression of dental caries, and hydrogen peroxide (H2O2) has been identified as a crucial factor in controlling lactic acid producing bacteria. We therefore propose to develop a quantitative and easy-to-read electrochemical biosensing platform that will use live dental plaque samples for potential point-of-care diagnostics to test the following hypothesis: can the capacity of dental plaque to produce metabolites-such as H2O2, associated with oral health, and lactic acid, linked to caries development-be used to establish threshold values for the early detection of caries? Aim 1: detect and quantify hydrogen peroxide and lactate produced by varying ratios of the bacterial species S. Sanguinis (SS) and S. Mutans (SM). Our innovative electrochemical sensors will be used along with microliter volume droplet hydrogel electrochemical cells, which can trap and analyze the picomoles of metabolites (H2O2 and lactate) produced by different ratios of beneficial bacteria (SS) and pathogenic bacteria (SM). Aim 2: establish a correlation between oral caries conditions and untreated dental plaque metabolic activity. We will establish the correlation between the ratio of H2O2 to lactate produced by dental plaque from patients and determine the threshold value that distinguishes non-caries from early caries conditions. We will also investigate the time-dependent metabolic activity of dental plaque in the presence of various sugars such as glucose and sucrose to gain insights into the cariogenic potential of dental plaque samples. Our analytical platform will eliminate the need for sample pretreatment, separation, or preconcentration and thus will enable the rapid and accurate analysis of metabolites produced by dental plaque. This study will validate dental plaque as a noninvasive BIO-sample for point-of-care diagnostics in oral health, paving the way for early detection of dental caries and personalized prevention plans. The need for invasive treatments will thereby be reduced, ultimately lowering healthcare costs.