You know who’s going to tell you you forgot to floss before going to bed? Your tooth! Princeton researchers have developed a tooth tattoo that can sense your body’s vital statistics, and not just the one’s in your mouth. It can will transmit your stats to a doctor or hospital for diagnosis. The design looks like a kind of tin foil QR code that affixed to the back of a tooth, which as Gizmodo reports, “could come in handy for military personnel in the field to determine whether a wound has become infected, or in hospitals where patients with weakened immune systems are extra vulnerable to bacteria.”

Right now, these teeth tattoos are more temporary than that happy-face skull and crossbones your kid got at the fair last year. They probably won’t last more than one tooth brushing.