A touch screen interface of a medical or dental device coupled with a touchless interface to allow for sterile zone operator input, while still allowing for touch screen interaction for non-sterile zone operator input. In some embodiments, the touch screen interface usage is suspended while in a sterile zone mode, and resumed when the mode is switched to a non-sterile zone mode. In some embodiments, use of the touch screen interface while in a sterile zone mode of operation causes an alert message.