Abstract: A system providing a water and particle tight seal in a home prophylaxis unit is disclosed. Such units normally include a hollow plastic handle, a plastic housing extending from the handle and having a rotatable prophylaxis element at its free end, and a drive shaft within the housing which drives a prophylaxis element.
Abstract: A hand held motor driven dental prophylaxis device constructed primarily of plastic or other thin walled material is disclosed. The device includes a radially adjusting bearing circumscribing and supporting its drive shaft to minimize the imposition of side loads on the electric motor. The device also includes a switch which will operate reliably even if the apparatus is flexed or distorted.