Abstract: A water-driven toothbrush and water-pick assembly is provided having a housing 1, a handle 3 pivotally attachable to the housing 1 and an elongated toothbrush arm with a brush 41 and water-pick outlet 43 at one end, attachable to the housing also. A water turbine rotor 11 in the housing 1 is connected to the arm 2 via an eccentric link 30 for converting rotary motion of the rotor 11 into agitating pivotal movement of the arm 2 and brush 41. The handle 3 can be pivoted between two positions in one of which water supplied to the handle 3 can be passed to the rotor 11 and exhausted from the handle 3 to actuate the toothbrush arm 2 only to clean a users teeth and in the other of which water supplied to the handle 3 can be passed to the water-pick outlet 43 only to provide a water jet for cleaning crevices between the users teeth.