Abstract: An adjustable toothbrush where the user can select, by turning a thumb knob on the brush handle, the inclination of the bristles to thereby improve on the cleaning of those hard to reach areas of the dentition. The toothbrush comprises a handle, a hollow brush body, a plurality of bristle bundles having their base moulded into resilient holders, a cam plate, a thumb knob connected to a cam shaft and a brush body cover. The cam plate slides within the hollow brush body and the brush body cover in a plane perpendicular to the bristles, and under the action of the thumb knob. The cam plate has a plurality of cavities for receiving the end of the bristle holders. Thus the movement of the cam plate is transmitted to all bristles in harmony.