Is this cool or what?
The researchers envision NailO helping people control wireless devices when their hands are full—for example, answering the phone when they’re cooking, or inspecting a circuit board’s layout on a computer while holding a soldering iron.
via MIT Turns Thumbnail into Trackpad – IEEE Spectrum.
The obvious dental use would be in the clinical area during treatment the dentist, assistant or hygienist could bring up images, zoom in on a radiograph or quick check a medical condition without interrupting treatment or breaking asepsis.