Research progress on flexible sensors in oral health monitoring

Abstract

Oral health is closely related to facial aesthetics, mastication, pronunciation, and systemic diseases. Flexible sensors can improve current deficiencies in clinical diagnosis and treatment through oral health monitoring. This paper reviews the research on and application of flexible sensors in oral health monitoring in recent years, providing a reference for the further development of flexible sensors in the oral field. The structural basis of flexible sensors includes a flexible substrate, stretchable electrodes, and an active layer, and each part is designed through material selection to adapt to the oral environment. The sensing mechanisms of sensors involve electricity, optics, electrochemistry, and immunology, among which electro-chemical, biological, and optical sensors are particularly prominent in the oral field. The monitored signals include physical signals such as orthodontic force, bite force, respiratory humidity, and implant temperature; chemical signals such as saliva metabolites and oral gases; and biological signals such as periodontal disease and oral cancer markers. At present, flexible sensors still face many challenges in this special oral environment. Future research directions include improving the biocompatibility, moisture resistance, and flexible fitting ability of sensors in the oral cavity; using temperature-insensitive materials and protective films to improve stability; and introducing artificial receptors and sensor arrays to improve factors such as selectivity. In addition, multi-disciplinary cooperation is crucial for breaking through current bottlenecks and achieving more accurate disease diagnosis and health monitoring. In the field of stomatology, finding specific biomarkers related to corresponding oral diseases is the key to sensor health monitoring. Through these efforts, flexible sensors are expected to gain more extensive applications in the field of oral health monitoring.