An apparatus that delivers a temperature-controlled fluid to a dental handset includes a tube assembly including an outer tube and a first inner tube. The first inner tube includes a first input end configured to removably attach to a first source port of a system delivering a first fluid and a first output end configured to removably attach to a first input port in the dental handset. The tube assembly also includes a heating element making good thermal contact with the first inner tube, and a first temperature sensor. The heating element and the first temperature sensor are configured to be operably connected to a temperature control unit such that the temperature control unit controls the heating element in response to a signal received from the temperature sensor.
