Engineered peptides that sense disease conditions in the mouth could give dentists a more precise way to control cavity-causing bacteria and repair early lesions, according to a review published in The Journal of the American Dental Association.
The findings come from a narrative review by researchers at the University of Otago in New Zealand and two universities in China, published in the October 2026 issue of JADA. The research was funded by a grant from the New Zealand Dental Research Foundation. The review does not report original data, and the authors write that most smart peptide systems remain preclinical.
Here are eight things to know from the review:
- There were 2 billion people worldwide with untreated caries in permanent teeth in 2022, according to the World Health Organization. The review says current treatment options have drawbacks: fluoride has limited ability to reverse deeper lesions, chlorhexidine shifts the oral microbiome and can stain teeth and alter taste, and silver diamine fluoride can stain teeth and leave a metallic taste.
- Smart peptides are short, engineered protein fragments designed to recognize caries conditions, such as acidic pH, specific bacteria or demineralized tooth surfaces. The authors say some are modeled on antimicrobial peptides the body already produces, while others are designed from scratch. They are attractive because they are biocompatible and easy to synthesize.
- Targeted antimicrobial peptides attach a bacteria-seeking segment to a broad-spectrum killing segment. One of the most studied, C16G2, selectively eliminates Streptococcus mutans in multispecies biofilms while sparing noncariogenic species, according to the review. A separate peptide, P19, is an antifungal that disrupts fungal cell membranes. The review notes that Candida albicans, a fungus, is associated with the severity of early childhood and root caries.
- The pH inside active caries lesions is below 5.5, compared with about 6.7 in a healthy mouth. Several peptides, including GH12 and LH12, are designed to become more active in that acidic environment, which the authors say reduces off-target effects.
- P11-4 is one of the most widely studied self-assembling peptides in the review. It forms a scaffold in acidic early lesions that encourages mineral growth, and clinical studies have shown it can improve remineralization of early enamel lesions and help resolve white-spot lesions. The review does not cite clinical studies for other remineralizing peptides, such as QP5 and ID8.
- Multifunctional peptides combine antibacterial and mineral-repair functions in one molecule. The most complex example, 8DSS-C8-P-113, joins three functions: antimicrobial activity, S. mutans targeting and mineralization. It acts as an antimicrobial at lower concentrations and forms a protective hydrogel at higher ones. The authors say these systems have shown promising laboratory results but need clinical trials.
- Potential clinical uses include treating patients at high risk for caries. The authors point to older adults with root caries, patients with dry mouth or those undergoing head and neck radiotherapy, children with early childhood caries and orthodontic patients, whose brackets could be coated with peptides for protection that does not depend on patient compliance. They also suggest peptides could be added to adhesives, liners and restorative materials to reduce secondary caries, a cause of restoration failure.
- Remaining barriers include peptide instability in the mouth, enzymatic degradation, manufacturing scalability and cost. The authors say well-designed clinical trials are needed to establish long-term safety and efficacy, and they call for standardized preclinical models and comparative effectiveness studies.
