Electrochemical Biosensing Strategies for Oral Health: From Engineered Interfaces to Advanced Transistor Architectures

Oral diseases represent a major global health burden, underscoring the need for sensitive, accessible, and noninvasive diagnostic technologies. Electrochemical biosensing offers a powerful route for point-of-care oral health monitoring by translating biomolecular interactions in saliva, gingival crevicular fluid, and exhaled breath condensate into quantifiable electrical signals. This review systematically discusses electrochemical biosensing strategies for oral disease diagnosis, beginning with the structure and operating mechanisms of electrochemical sensors and then summarizing their applications in detecting disease-related nucleic acids, proteins, pathogens, and other molecules. We further examine feasible strategies for early diagnosis, including signal amplification methods based on nanomaterials, enzyme catalysis, nucleic acid amplification, chemical deposition, and cascade integration, as well as antifouling interfaces designed to maintain stable sensing performance in complex oral biofluids. Particular attention is given to advanced transistor architectures, especially organic electrochemical transistors (OECTs), which offer intrinsic signal amplification and high-gain readout for low-abundance biomarkers. Finally, we outline current challenges, future directions, and translational opportunities for electrochemical biosensing technologies, providing a roadmap toward precision dentistry and modern oral health management.