the process involves the application of heated water , above 40 ° c ., to the teeth with simultaneous rotary brushing to remove plaque . the apparatus is a turbine power unit adapted to be connected to the heated water faucet and adapted to sit in the sink . a heated water exhaust conduit from the unit and a flexible power shaft lead to a handpiece which has a rotary brush driven by the shaft and a nozzle connected to the conduit and directed at the brush .