Smart Tooth System for In-Situ Wireless PH Monitoring

In this paper, we introduce an oral motion-powered Smart Tooth system that can monitor oral health. Lower pH is an indicator of bacterial accumulation in the oral cavity, which can cause tooth decay, periodontal or peri-implant diseases. Thus, in situ monitoring pH inside of the mouth is critical to prevent oral diseases. Using a piezoelectric dental crown, Smart Tooth system converts oral motions, such as chewing, to electrical power which can impinge a surface integrated LC transponder. The LC transponder also incorporates iron oxide nanoparticles-embedded pH-sensitive hydrogel that modulates the resonant frequency via shrinking or swelling. As a proof of concept, the fabricated prototype measures pH levels ranging from pH 4 to 12 and sends data wirelessly to the receiver placed up to 5 cm away (wireless transmission path loss at 3 cm was 50.79 dB). The results indicate that the Smart Tooth system can monitor oral health while replacing missing teeth.