A handheld surgical device with a working portion driven by a motor, wherein the working portion is contained in a concave-shaped portion when it is not activated, and the working portion becomes exposed from the concave-shaped portion when it is activated. The activation of the working portion can be controlled by a switch located at a handle portion of the handheld surgical device. The handheld surgical device includes a concave-shaped portion with a cutting edge, which is not driven by the motor.