Abstract: A perforator for cutting a hole in bone tissue is provided. The perforator comprises an anchor, a hole cutter configured to rotate around the anchor, and conversion means for converting rotational motion of the hole cutter around the anchor into linear motion of the hole cutter towards the material to be cut. The invention is usable to cut holes in a wide variety of materials, in particular for a perforator for cutting a hole in a skull of a human or animal. A kit of parts and a method of cutting a hole are also provided.

Abstract: A perforator for drilling bone tissue has: a drive shaft with a rotational axis A; an inner cutting head with the same rotational axis A; a drive surface provided on the drive shaft; and a connector provided on the inner cutting head. The inner cutting head is displaceable with respect to the drive shaft along the rotational axis between a distal position, in which the inner cutting head is not driveable by the drive shaft, and a proximal position, in which the drive surface abuts the connector to transmit rotational motion from the drive shaft to the inner cutting head. The drive surface is inclined relative to the rotational axis A.

Abstract: In a method for controlling a torque of a motor of dental and surgical handpieces to not exceed a set-point value when screwing in implant members, a motor current for applying the set-point torque is determined immediately before screwing in an implant member with the handpiece and the motor current is limited to the set point value with a motor control during subsequent screwing in of the implant member. The device for carrying out the method has a torque limiter, connectable to a tool receptacle of a handpiece, and a motor current measuring device for measuring a motor current of the motor of the handpiece.

Abstract: A handpiece for use in small-scale surgery and microsurgery, for example, oral surgery or surgery in the ear, nose and throat area includes a handpiece sleeve and a collet chuck which is rotatable about an axis and is arranged in the handpiece sleeve. The collet chuck is spring-biased and can be released by an actuating member. The collet chuck serves to hold a tool and is composed of two tubular members which are movable relative to each other along the axis of rotation of the collet chuck. A chucking lever for releasing the collet chuck is pivotable about a lever axis which is directed essentially in normal direction relative to the collet chuck axis. The actuating member includes a drive member which is movable in axial direction together with the two tubular members of the collet chuck, but does not rotate together with the tubular members. The drive member projects with a portion thereof in direction of the collet chuck axis into an undercut portion of the chucking lever.