Sustainable Solutions for Oral Health Monitoring: Biowaste-Derived Triboelectric Nanogenerator

Oral healthcare monitoring is a vital aspect of identifying and addressing oral dental problems including tooth decay, gum pain, and oral cancer. Day by day, healthcare facilities and regular checkups are becoming more costly and time-consuming. In this context, consumers are moving toward advanced technology, such as bite sensors, to obtain regular data about their occlusal chewing patterns and strength. The triboelectric nanogenerator (TENG) can potentially eliminate the need for a battery by simply converting abundant vibrations from nature or human motion into electrical energy. In this work, biomaterials are obtained from biowastes such as cellulose from wood waste, chitosan from crab shells, and gelatin from fish scales. All wastes are biodegradable, and our work aims at sustainability and waste hierarchy. The single electrode mode-based TENG was designed and fabricated using biodegradable poly(vinyl alcohol) (PVA)-biomaterial composites, rice paper as a substrate, and edible silver leaf as an electrode. The highest electrical output was obtained for PVA/chitosan 10 wt % composite-based TENG (PC10) of about 20 V, 200 nA, and 12 nC. The biomechanical energy harvesting was measured, and powering of LED was demonstrated using a PC10 TENG device. A biocompatible bite sensor based on the TENG was used to measure the biting force of a dummy teeth model to demonstrate its potential use in dental health applications. It indicates the promising future value of disposable oral medication devices without any invasive surgery or injection.