Oral health monitoring has become an important component of precision medicine for assessing physiological indicators. The oral cavity and respiratory tract are promising sites for continuous monitoring of vital signs and exhaled biomarkers relevant to clinical care, including critical care settings. However, conventional sensors face limitations for long‑term intraoral or airway deployment related to power supply, size, and biocompatibility. This review examines how nanogenerators (NGs) can address these limitations by harvesting local biomechanical or environmental energy to achieve self-powered sensing.
The oral cavity presents several unique and demanding conditions that complicate sensor design and use: consistently high humidity, restricted and irregularly shaped spaces, mechanical forces from chewing and speaking, and a microbiologically complex environment. Traditional sensors and monitoring devices frequently suffer from poor biocompatibility, the need for frequent battery replacement, and size constraints that reduce patient comfort and feasibility for long‑term wear. High energy consumption in conventional intraoral monitoring systems increases maintenance costs and limits durable clinical use.
Nanogenerators convert mechanical, thermal, or environmental stimuli into electrical energy using effects such as triboelectric, piezoelectric, and pyroelectric transduction. By integrating NGs with sensing elements, devices can scavenge energy from oral biomechanical motion (for example, jaw movement, breathing) or environmental changes and power continuous monitoring without external batteries. These mechanisms underpin NGs’ potential to enable miniaturized, biocompatible, and autonomous sensors suited to the oral‑respiratory interface.
NGs have been explored for respiratory monitoring by harvesting energy from breathing‑related airflow or tissue motion and converting it into signals that reflect respiratory rate, airflow dynamics, or other mechanical respiratory parameters. Such self-powered respiratory sensors could provide continuous vital sign surveillance with reduced maintenance compared with battery‑powered devices, making them attractive for long‑term monitoring in outpatient, inpatient, and critical care contexts.
Beyond mechanical monitoring, NG‑coupled systems can support exhaled gas analysis and diagnostic sensing. Harvested power can be used to drive sensing modalities or supply readout electronics for detection of gaseous biomarkers in breath. The review highlights the potential for NGs to contribute to noninvasive diagnostics by enabling continuous or repeated breath sampling and analysis at the oral‑respiratory interface.
NG technology has also been applied in electronic skin and wearable formats that interface with oral or facial tissues. These thin, flexible devices aim to provide conformal contact, tolerate the moist oral environment, and transduce mechanical or thermal cues into electrical signals. The integration of NGs into wearable oral sensors seeks to overcome limitations of size and power while maintaining sufficient biocompatibility for extended use.
A central theme identified by the authors is the need to bridge material choice and structural design with the specific clinical demands of the oral‑respiratory environment. Factors to consider include moisture resistance, mechanical robustness to withstand chewing and speech, biocompatibility for mucosal contact, and miniaturization for patient comfort. The review underscores that tailored materials and device architectures are essential to translate NG concepts into reliable clinical tools for long‑term intraoral or airway monitoring.
Although NGs show rapid development in oral and respiratory applications, the review notes a distinct lack of systematic studies connecting tailored materials and structural designs to the harsh and variable clinical environment. The abstract does not present specific quantitative performance metrics, safety data, or clinical trial results; therefore, details about device durability, sensitivity, specificity, or regulatory readiness were not reported in the source abstract. This gap in systematic evaluation and reporting is highlighted as a barrier to clinical translation.
The review concludes that NGs have immense potential and clinical value for frontier applications such as critical care vital sign monitoring, exhaled gas analysis, and long‑term stable organ monitoring. By offering self‑powering, miniaturization, and improved biocompatibility, NG‑based sensors could reduce maintenance burdens and expand monitoring capabilities. Future efforts should systematically align material science and device engineering with clinical testing scenarios to address the practical challenges of the oral‑respiratory environment.
This article synthesizes developments in triboelectric, piezoelectric, and pyroelectric nanogenerator technologies applied to oral and respiratory sensing. It highlights the clinical need for self‑powered, biocompatible, and miniaturized devices for long‑term monitoring and diagnostics, and it identifies a gap in linking materials and structural design to clinical constraints. The review outlines applications across respiratory monitoring, breath‑based diagnostics, and wearable electronic skin, and it calls for targeted research to overcome current limitations and expedite clinical translation.
Note: The abstract and bibliographic information were the sole sources for this summary. The original article likely contains more detailed experimental results, device examples, and performance data that were not reported in the PubMed abstract.