Salivary Innate Immune Peptides Correlate with Lower Dental Caries Experience in Young Adults

Dental caries, a prevalent chronic disease, traditionally linked to diet and oral hygiene, involves complex host-pathogen interactions. While salivary flow rate, pH, and buffering capacity are established indicators, the role of specific innate immune components, particularly antimicrobial peptides (AMPs), in modulating caries susceptibility remains less explored. Understanding these intrinsic host defense mechanisms could reveal novel biomarkers and therapeutic targets, addressing the current gap in comprehensive caries risk assessment and personalized prevention strategies beyond conventional approaches. This study investigates the association between salivary AMP levels and caries status.

Researchers recruited 40 healthy volunteers aged 18-35 years from university dental clinics. Participants provided stimulated saliva samples and were categorized into either a low-caries or high-caries experience group based on ICDAS criteria and DMFS index scores. Levels of specific antimicrobial peptides, including human β-defensins 1-3, histatin-5, and cathelicidin LL-37, were precisely quantified in the collected saliva using peptide-specific ELISA kits. This cross-sectional design aimed to correlate AMP concentrations with existing caries status.

The study revealed a significant association between salivary antimicrobial peptide concentrations and dental caries experience.

All measured AMP concentrations—human β-defensins 1-3, histatin-5, and cathelicidin LL-37—were significantly higher in individuals classified with low caries experience compared to those with high caries experience (p < 0.001). This robust statistical difference suggests a strong protective role for these innate immune peptides. Furthermore, a clear negative association was observed between D1-6MFS scores, a comprehensive measure of caries severity, and the concentrations of salivary AMPs. This indicates that as the levels of these protective peptides decrease, the extent of dental caries tends to increase. The consistent elevation of multiple AMPs in the low-caries group underscores their collective contribution to host defense against cariogenic challenges.