A noiseless handpiece providing indicator lights. The head portion of the handpiece has one or more internal silencers for baffling the noise that is a byproduct of the generation of the rotational force used to drive the drill component. The indicator lights communicate one or more operational states to the user and reflect the engagement of an electrically connected transducer.

A root canal therapy device with a mechanical vibration mode and a rotation drive mode includes a head, a handle, a first flexible drive shaft and a second flexible drive shaft. The head includes an outer main part, a mandrel part for mounting a root canal file, a first drive input shaft part and a second drive input shaft part. The mandrel part is mounted in the outer main part. A first drive motor and a second drive motor are disposed on the handle. The invention has the following beneficial effects: the root canal file can rotate and vibrate during root canal preparation, so that the wall of a root canal is efficiently cut by the file; and the file can also vibrate, so that cutting resistance and cutting temperature are effectively reduced, a smear layer is avoided, and the quality and efficiency of root canal preparation are improved.

A medical or dental device for determining a bone's quality by cutting a thread into the bone with a rotating threaded element comprises a control unit having a measurement circuit configured: (i) to determine values of the motor current via a first electrical contact device with which the motor drive is supplied for rotational drive of the threaded element that can be connected to the motor drive, the current values being a measure of the bone's quality; (ii) to monitor and/or to determine the penetration depth of the threaded element into the bone, and (iii) to generate measurement signals which show the relationship between the penetration depth and the determined current values or parameters derived therefrom, and to transmit these signals to a display unit, which displays the relationship between the determined current values or parameters derived therefrom, in particular the bone's quality, and the penetration depth.

Provided is a system for endodontic treatment of a root canal. The system includes a handpiece containing a rotary motor adapted to rotate an endodontic file secured by the handpiece. A control unit executes a regime of motion of the motor to produce a regime of file motion in which episodes of oscillation of the file are separated by a rotation of the file. When the arc of a rotation is less than the arc of the oscillation that preceded the rotation, the arcs of the episodes of oscillation overlap and the formation of ridges in the root canal is avoided.

A multi-directional handpiece that includes a motor drive extending along and configured for rotation about a body axis, the motor drive having: a motor gearing at a proximal end of the motor drive; and a file gearing in engagement with the motor gearing for transferring the rotational and axial movement to a workpiece; and a housing for the workpiece; and wherein through rotation of the motor drive, the workpiece moves in an axial oscillating motion while being rotated.

A dental handpiece control apparatus including: a relay 17 that switches a polarity of a voltage applied to a motor 20, and thereby switches a rotation direction of the motor 20 to forward rotation and backward rotation, the motor 20 being incorporated in the dental handpiece to rotate a cutting tool (a file) mounted to the dental handpiece; and a control section 11 that controls the switching of the voltage polarity by the relay 17 based on a rotation angle θ.sub.F for forward rotation and a rotation angle θ.sub.R for backward rotation of the motor 20, the rotation angle θ.sub.F and the rotation angle θ.sub.R being associated with state information of the file.

The present invention relates to a device and a method for measuring osseous quality.

The present invention relates to a hand operated dental instrument that allows a user to manually operate tool bits that are ordinarily operated by a power operated tool or a unitary hand-held device. The invention includes a handle that carries a shaft; a bore-hole extending through at least a portion of the shaft for receiving a portion of a tool bit; and a spline receiving slot defined in the shaft. The invention also includes a tool bit having a flange that may carry a spline extending along a portion of a longitudinal axis of the tool bit so that when the tool bit is placed in the bore-hole, the spline receiving slot receives the spline so that when the shaft is rotated, the tool bit rotates.

A medical or dental fluid-driven handle with a control or regulation circuit for the control or regulation of the rotational speed of a rotary part to a predetermined rotational speed and methods are presented. The handle comprises a rotary part that can be set in rotary motion by a drive fluid, a fluid line carrying the drive fluid to or from the rotary part or a fluid branch line that is connected to a fluid line carrying the drive fluid, and a control or regulation circuit that is designed to control or regulate the rotational speed of the rotary part. An electrodynamic converter is driven by the rotary part for generating electrical energy. An actuator element is configured to act on the drive fluid and is electrically connected to the electrodynamic converter such that the actuator element is supplied with electrical energy generated by the electrodynamic converter.

A reciprocating endodontic hand tool in which the torque applied to an instrument such as a debriding file can be set at or below an endurance limit of the file below which failure of the instrument will not occur. In preferred embodiments the tool can switch between settings in which the torque applied to the instrument is between the endurance limit of the file and an elastic limit of the file, by setting forward and reverse angles of rotation within specified limits. This reduces or eliminates opportunities for plastic distortion, fatigue and breakage of the file during the canal debriding/cleaning/shaping process in a root canal treatment or retreatment. In some embodiments the torque may be set to at or below a durability limit of the file below which failure of the instrument will not occur through repetitive strain over the course of a particular root canal treatment or retreatment.