Abstract: Bone reduction forceps provide both continuous and discrete adjustment of force. A worm gear rotatably attached to one arm of the forceps engages a rack attached to another arm of the forceps to provide both the continuous and discrete force adjustment. Buttress threads on the worm and/or the rack allow for rapid closure by squeezing the handles of the forceps. Rotating the worm gear allows for fine adjustment of closing force. A five-bar linkage provides increased mechanical advantage and an extra degree of freedom, compared to conventional forceps. Interchangeable tips provide flexibility, allowing a user to customize the forceps to a task or the user's preferences.

Abstract: A powered surgical device for cutting or drilling having a mechanical cutting or drilling assembly, a fluid inlet, and a vacuum source port for connecting to a vacuum source. The vacuum source port is disposed in fluid communication with the fluid inlet. The surgical device is configured and arranged to cause an aerosol generated by the mechanical cutting or drilling assembly to be suctioned into the fluid inlet when the vacuum source port is connected to a vacuum source.

Abstract: Methods and systems for tracking a dental tool within an oral cavity for taking and/or updating of a dental impression are described. In some embodiments, a marker, optionally a magnetic marker, is coupled to position movements of a rotatable dental tool. In some embodiments, detected movements of the marker are used, optionally in combination with other tracking data, to map contours which a portion of the rotatable dental tool follows during interaction with a dental surface. Optionally, the interaction occurs during grinding, drilling, and/or other procedures; which may be preparatory, for example, to the manufacture and/or fitting of a dental prosthetic.

Abstract: Medical or dental instruments having a lighting device, manufacturing methods for such instruments and various lighting devices having an optical semiconductor element are described. The lighting devices have, for example, a body, at least one radiation-emitting surface on a radiation-emitting end of the body and at least one fluid channel which is provided in the body and connects at least one opening which is provided on the radiation-emitting end to one or more fluid sources for dispensing fluid. The lighting devices have, for example, a hollow metallic sleeve, a transparent window for emission of electromagnetic radiation and a socket on which at least one optical semiconductor element is arranged. The socket is made of a ceramic, glass ceramic or glass material, and is connected to the hollow metallic sleeve by a material comprising metal and glass.

Abstract: A cartridge seal for sealing a space between a housing and a rotatable shaft includes a rotary sealing member having an inner surface defining a bore for receiving the shaft and a circular outer flange extending radially outwardly from and circumferentially about a central axis, the outer flange having a radial sealing surface. A static seal assembly is disposed about the rotary member and includes an annular casing coupleable with the housing and an annular static sealing member disposed within the casing and having a radial sealing surface engageable with the rotary member sealing surface to form a sealing interface. A biasing member axially biases at least a portion of the static sealing member toward the rotary member flange. An annular collar is disposed within the casing and axially retains the rotary member within the casing such that the seal assembly is mountable on a shaft as a single unit.

Abstract: Embodiments of the invention are directed to a medical device with a handpiece that provides enhanced comfort of use, maneuverability, and for a variety of hand-held options to the user. Embodiments of the invention include handpieces that include a grip panel comprised of a friction-enhancing material to facilitate gripping of the handpiece by an operator. In addition, embodiments of the invention include handpieces having a generally symmetrical configuration in order to facilitate grasping by an operator's left or right hand.

Abstract: Surgical system, in particular a dental system including a surgical instrument, in particular a dental instrument and a device for controlling the electronic instrument. The device for controlling the electronic instrument includes a first electronic module. The instrument includes a rotary motor for driving the tool and a second electronic module. The rotary motor of the instrument is electrically powered by the first electronic module of the control device through the first electrical conductors dedicated to supply the rotary motor. The instrument is powered and/or electrically controlled by the first electronic module of the control device only through the second electrical conductors distinct from the first electrical conductors. The system also includes a management module of the second electrical conductors for sending on the second electrical conductors a number of signals larger to a number of second electrical conductors.

Abstract: A medical or dental handpiece which has an outer sleeve, a tool-holding sleeve for holding a treatment tool, wherein the tool-holding sleeve has a central axis about which the tool-holding sleeve can be rotated and wherein the tool-holding sleeve can be induced to a stroke motion by a driveshaft of the handpiece, and an adjusting device, which is designed to secure the tool-holding sleeve selectively in a rotational position or to allow a free rotatability of the tool-holding sleeve, wherein the adjusting device has a fixation element, which secures or releases the tool-holding sleeve and at least one adjusting element, which is at least operatively connected to the fixation element, wherein the adjusting element is movable substantially in parallel with the central axis of the tool-holding sleeve.

Abstract: A method and device for programming a cordless handpiece used for root canal treatment and having a first memory and a tool holder for a treatment tool are described. The method includes providing a first data volume having a plurality of data sets in a second memory separate from the first memory, each of the data sets comprising at least one parameter assigned to the cordless handpiece and/or to the operable tool, selecting at least some of the data sets from the first data volume in the second memory, transmitting the selected data sets from the second memory to the first memory of the handpiece, and selecting a data set from the updated first memory for operation of the handpiece.

Abstract: A bearing assembly (20) for use in a medical, surgical, or dental handpiece (10) that enables spindle rotation for a supported rotary tool (36) at high speeds. The bearing assembly (28) incorporates annular gap shields (50, 54) at each axial end to prevent contaminate ingress and to retain lubricating grease within the bearing assembly (28) to avoid re-lubricated after each use or sterilization cycle.

Abstract: An implant system can include a first rotatable flexible shaft comprising a biocompatible material and configured to be used as an implant for placement in the human body, the implant including an implant driving element positioned at a proximal end; a second rotatable flexible shaft including a cutting drill positioned at a distal end and a drill driving element positioned at a proximal end; and a surgical tool capable of being connected, in the alternative, to the drill driving element for forming a recessed surgical site and to the implant driving element for placing the implant in the recessed surgical site.

Abstract: The medical or dental handpiece comprises a rotary part and at least one roller bearing which is provided for bearing support of the rotary part. The roller bearing has a bearing inner ring and a bearing outer ring, each having a raceway for the at least one rolling element arranged therebetween. The rotary part is mounted on at least one bearing ring on the side having the raceway for the at least one rolling element.

Abstract: The present invention relates to dental machining apparatus (1) for blanks (3) comprising a tool spindle (2) having an axis of rotation (2.8) and mounted in a bearing housing (1.2) disposed on the machine housing side. A force sensor (5) is also provided, which is disposed between the tool spindle (2) and the bearing housing (1.2) for the purpose of detecting the machining force acting on the tool spindle (2), wherein the tool spindle (2) can be supported against the bearing housing (1.2) directly or indirectly via the force sensor (5).

Abstract: A coupling device for detachably connecting a medical or dental instrument to a drive unit or a supply hose for transfer of at least one of data, energy, a driving movement and a working medium between the drive unit or the supply hose and the instrument comprises a first coupling element and a second coupling element. One of the coupling elements comprises a coupling recess and the other comprises a coupling protrusion insertible therein. One of the coupling elements comprises a positioning element and the other comprises an indentation into which the positioning element can be inserted to position the coupling elements in a defined angular position about a shared axis. One of the coupling elements comprises a memory unit for storage of data and the other comprises a transfer unit, so that data can be transferred from the memory unit by the transfer unit to the other coupling element.

Abstract: An intelligent dental handpiece control system is disclosed. The handpiece includes a sensor which detects a vibration, sound, force or torque frequency/time signal produced by the handpiece in use and signal processor which produces or determines secondary signal characteristics such as the handpiece torque, force or angular velocity. A controller analyzes the secondary signal characteristics and produces a control signal which controls or stops the angular velocity of the dental handpiece in order to avoid overdrilling of healthy tooth material or damaging the nerves in the jaw during dental implant operations. The controller may also provide a warning signal to the user and/or control the angular velocity of the handpiece.

Abstract: A dental handpiece capable of withstanding a higher torque load includes a driving source which rotates a first rotating shaft 3 which is supported rotatably in a rear casing 2R, which transmits rotation to a second rotating shaft 9 which is supported rotatably in a front casing 2F. First and second bearings 12,14 are disposed at a predetermined interval in a jacket 8 fixed in the front casing 2F to rotatably support the second rotating shaft 9, and a third bearing 13 is disposed between the first and second bearings 12,14. The third bearing 13 reduces the whirling of the second rotating shaft 9, thereby preventing the wearing and chipping of the teeth of gears caused by a shift of meshing positions between a first gear 5 and a second gear 10 and a shift of meshing positions between a third gear 11 and a fourth gear 73.

Abstract: In one embodiment, a system for making a dental restoration is provided. The system includes a machine unit for processing a dental material to form the dental restoration, and a control unit for controlling the operation of the machine unit. An air channel for discharging a process-originated material from the machine unit provides an air connection between the machine unit and the control unit. Certain embodiments of invention are advantageous in that they help to increase the reliability of the machining operation.

Abstract: A dental tool including a dental prophy angle and a dental prophy angle adapter is provided. A dental prophy angle includes a housing and a rotor. The dental prophy angle adapter can include a drive shaft with a tip. The drive shaft of the adapter can be coupled to a gear at the same end of the tip with the rotor of the prophy angle being configured to receive the tip. Further, a slidable sleeve can extend over a portion of the drift shaft so that the slidable sleeve becomes automatically retracted upon engaging a shoulder of the housing resulting in the gear of the drive shaft being positioned beyond the end of the slidable sleeve.

Abstract: There is disclosed a medical or dental hand-piece element comprising a coupling mechanism for a detachable connection of the hand-piece element to a drive unit, a tool receptacle that is or can be connected to the hand-piece element, and a drive element for transmitting a driving movement from the drive unit to the tool receptacle so that the tool receptacle can be set into a working movement, wherein the drive element comprises at least one rotatable shaft, and a generator for converting mechanical energy into electric energy, wherein the generator can be driven by the at least one rotatable shaft of the drive element.

Abstract: A method and corresponding system for operating a dental handpiece, wherein the handpiece comprises a motor for driving a tool. the method comprises (a) sequentially capturing values of a physical parameter, which—at least approximately—represent the power or energy fed to the motor, (b) forming an integration value by integrating the values captured in (a), and (c) automatically reducing a power or energy fed to the motor if the integration value formed in (b) exceeds an upper threshold value. The integration value formed in (b) represents a measure of the power integrated over time and can thus be used at least approximately as a measure of the temperature of the instrument. The automatic reduction in the power or energy fed to the motor performed in (c) can therefore effectively act against a further increase in temperature or allow cooling if the temperature of the instrument exceeds an upper threshold value.

Abstract: The present invention relates to an instrument used to insert microimplants and more particularly, to a microimplant insertion wrench that has a head on the instrument that allows the head to swivel and rotate upon the handle. The end of the head of the instrument comprises a receptacle that receives and retains a microimplant. The head of the implant wrench can be fixed into a predetermined angulation with the aid of a set screw. Microimplants can be inserted by a counter clockwise rotation of the knurled knob on the head of the instrument, and implants can be removed by clockwise rotation of the knurled knob on the head of the implant wrench.

Abstract: A fluid-operated medical or dental handheld element is disclosed, having a connecting device for connecting the handheld element to a fluid source so that a first impeller can be induced to rotate by a fluid stream to cause a tool to execute a driving motion, a fluid conducting device arranged between the connecting device and the first impeller for conveying a fluid stream away from or toward the first impeller, and a generator for generating electric power. The generator includes a second rotatable impeller that can be driven by at least a substream of the fluid stream conveyable in the first fluid conducting device. One result is more constant generation and output of power by the generator independent of the rotational speed of the first impeller, thereby insuring a more constant power supply to a power consuming device connected to the generator.

Abstract: A dental handpiece (1) includes mechanical components, in particular, a tool-holder assembly for the attachment and for the rotational driving of a dental instrument about a drive axis (6) and an assembly for the transmission of such movement. The mechanical components are mounted in the interior of a body (2) having a head (4) and a handle (3). The mechanical components of the handle and the head of the handpiece are electrically connected by an elastic and electrically conducting connecting device.

Abstract: A dental handpiece carries a drill and drives it in relative motion in a direction of penetration. The handpiece includes a body with a proximal end and a distal end, a removable head connected to the body's distal end, able to hold the drill, abutment means fixed on the dental handpiece by fixation means and able to limit the depth of penetration of the drill in the body of a patient. The abutment means, protruding from the dental handpiece, are fixed and locked on the dental handpiece by locking means which are actuated by the simple movement of joining the head to the body.

Abstract: A dental wrench device to loosen and extract teeth, comprising a handle with a fixed tapered jaw. A moveable jaw is also coupled to the handle. The tapered jaw is positioned along the root of a tooth selected to be extracted. The moveable jaw has a blunt contoured shape configured to grasp the gum and bone on the opposite side of the selected tooth at a level below the crown of the tooth. The device is applied and tightened around the selected tooth by turning a thumbscrew, or other jaw movement interface, that moves the moveable jaw end closer to the fixed tapered jaw end until the tooth is tightly gripped by the device. Once the wrench is locked into position, force may then be applied to extract the tooth. The device may also incorporate an optional force feedback gauge to warn the operator when excessive force is being applied.

Abstract: A dental clinical apparatus having a function which conventional instruments for dental treatment have not had and having a novel constitution. The dental clinical apparatus includes a syringe which has a fluid jetting system for dental treatment and a plasma jet applying means for producing a plasma jet from the end by allowing a low-frequency high-voltage power supply to apply a low-frequency high voltage between electrodes on the outer peripheral surface of a rare gas tube through which a rare gas having a low dielectric breakdown voltage under the atmospheric pressure is flowed, and thereby causing electrical discharge.

Abstract: Disclosed is a trephine drill for an implant. The trephine drill for the implant includes: a perforating body which comprises a first end part provided with a cutter for perforating the alveolar bone and a second end part formed with a through hole; and a rod body which couples with the perforating body to move close to and apart from the first end part of the perforating body toward the through hole of the perforating body and adjusts a perforation depth when perforating the alveolar bone. With this, not only an alveolar bone is precisely perforated at a preset depth, but also an alveolar bone piece, generated when perforating the alveolar bone, is easily removed from inside of a perforating body.

Abstract: The present invention provides methods for moving a tooth to a desired position within a patient's mouth using orthodontics including perforating tissue in the oral cavity sufficient to induce an inflammatory response. The perforations may be made in any area of the maxilla or mandible, and any number of perforations may be made that are preferably 0.5 to 1.5 mm diameter, and preferably 1 to 3 mm deep. The invention also provides a device that may be used in conjunction with slow-speed rotary instruments or with manual drivers for providing the perforations. The device has a drill that makes the perforations and a stop that prevents the drill from penetrating the jaw bone beyond a predetermined depth. The invention also provides a kit that supplies the professional with the necessary components in a sealed container to carry out the osteoperforations. The kit may include hand held and rotatory perforating devices, anesthetic, and a soft tissue punch.

Abstract: A bearing assembly (20) for use in a medical, surgical, or dental handpiece (10) that enables spindle rotation for a supported rotary tool (36) at high speeds. The bearing assembly (28) incorporates annular gap shields (50, 54) at each axial end to prevent contaminate ingress and to retain lubricating grease within the bearing assembly (28) to avoid re-lubricated after each use or sterilization cycle.

Abstract: A screw tap type device for loosening or extracting a wisdom tooth is provided. The device comprises a screw tap with a plurality of longitudinal cavities in the external screw thread, creating cutting teeth which create a strong frictional grip with a rough dentine wall of a previously drilled tapered tunnel of a wisdom tooth. A user can then twist the device to exert axial bodily dislocating force for easy loosening or extraction of the wisdom tooth.

Abstract: A drill for sinus membrane lift includes a contact surface for coming in face contact with sinus membrane, the contact surface having a curved periphery, and a bone-maintaining area connected to the contact surface for storing and discharging drilled bone fragments. The bone-maintaining area includes a first inside wall and a second inside wall connected to the first inside wall, the first inside wall oriented in a drilling direction, and the second inside wall opposite the first inside wall. The first inside wall has a drilling surface and is formed higher than the second inside wall so that the drilling surface is exposed in the drilling direction. The front end of the head comes into face contact with the sinus membrane at a wide area to prevent the sinus membrane from being torn or damaged even if the head completely penetrates the maxilla and contacts the sinus membrane.

Abstract: The medical or dental handpiece comprises a rotary part and at least one roller bearing which is provided for bearing support of the rotary part. The roller bearing has a bearing inner ring and a bearing outer ring, each having a raceway for the at least one rolling element arranged therebetween. The rotary part is mounted on at least one bearing ring on the side having the raceway for the at least one rolling element.

Abstract: A wireless dental handpiece includes a handpiece body that houses a rechargeable battery and a charging loop, and a charging socket that provides a power supply to the charging loop to charge the rechargeable battery upon insertion of the rear end of the handpiece body into the charging socket so that the dentist can use the dental handpiece conveniently, avoiding cable tangling.

Abstract: A dental handpiece having an embossed non-slip grip positively wrapping about the periphery of the handpiece body at a predetermined location for gripping with the fingers.

Abstract: A dental handpiece includes a body having a first portion and a second portion, the first and second portions disposed at an ergonomic angle to each other. A drive gear extends from the second portion toward the first portion. The drive gear has a first axis of rotation and rotatably drives at least one driven gear having a second axis of rotation. The at least one driven gear is operatively connected to a bur disposed in the first portion to rotatably drive the bur about a third axis of rotation. The drive gear and the at least one driven gear do not include a taper gear or a face gear.

Abstract: A device for forming a bone bed for dental implants having a head composed of crystal of partially stabilized zirconium dioxide with a nanostructure having a crystallographic axis that coincides with the axis of the bone bed forming device. The head has cutting elements formed as a rotatable plate. The plate has two broad facets formed by circular arcs that are convex relative to the axis of bone bed forming device. Transition from one of the convex circular arc to another convex circular arc is smoothed by circular arcs that are concave relative to the axis of bone bed forming device. Grooves form first and second cutting members with narrow facets of the plate. The head has an end part shaped as a truncated sphere possessing a recess formed by two planes arranged at an angle of 90° relative to each other and passing through the truncated sphere center and two points belonging to two diagonally arranged plate ribs.

Abstract: In a dental treatment instrument with an elongate grip sleeve, a drive unit arranged in the grip sleeve, and a coupling device which is located at the front end of the grip sleeve and with which a movement generated by the drive unit is transferred to a treatment tool to be connected releasably to the treatment instrument, the coupling device is designed like a sleeve and has a first section for receiving a tapering peg-like coupling area of the tool shaft, and a second section which also interacts with the tool shaft to provide a securing means acting in the axial direction, wherein the length of the first section of the coupling device is at least as great as the length of the second section.

Abstract: The invention concerns a handpiece for a surgical or dental tool (3), which can be inserted in the head of the handpiece (1) through an insertion hole (14) into a tool holder (2) and is rotationally supported by means of two axially separated bearings (12, 13), with positive torque transmission (8) to the tool (3) by the drive (9) installed in the handpiece, such that the tool possibly has a longitudinal bore (6) for supplying cooling liquid to the work site, and the handpiece (1) possibly has a short, fixed feed tube (7), which extends into the longitudinal bore and is sealed from the tool (3). To increase the torque that can be transmitted, the invention is characterized by the fact that the torque transmission (8) occurs in the region of the bearing (13) that is adjacent to the insertion hole (14). The invention also concerns the development of suitable tools.

Abstract: Medical, in particular dental, contra-angle handpieces for driving a dental instrument connected to the contra-angle handpiece with shafts arranged in the contra-angle handpiece for the transmission of the drive movement to the instrument. In order to achieve a reduction of sound emission and a reduction of the manufacturing and assembly costs while still incorporating the curvature of the outer sleeve of the contra-angle handpiece and the advantages which this entails, the contra-angle handpiece is equipped with a single-piece shaft which is essentially centered at the proximal end and the distal end of the outer sleeve, but runs eccentrically in a section of the outer sleeve between the proximal end and the distal end. The curvature of the outer sleeve of the contra-angle handpiece is in the range of about 8° to about 16°, and in some implementations, in the range of about 10° to about 14°.

Abstract: A hand held instrument for carrying out some function on a work piece. The instrument is a handpiece that is held by the user and includes a working element at the distal end of the handpiece for working on the work piece. There is a source of power that activates the working element by providing power thereto in various forms. There is also a pressure sensor that senses the pressure between the working element and the handpiece. In one embodiment that pressure sensor senses a predetermined pressure in order to couple the power source to the working element for activating the working element. In another embodiment, the pressure sensor senses a reduction in pressure between the working element and the handpiece to illuminate an indicator light.

Abstract: The handpiece includes at the front a collet arranged for strongly gripping the shank of a removable tool housed in guide bores. The collet includes two or several arms attached to an annular part of the collet to grip the tool shank. Preferably, the collet arms are levers each having a support surface which is far from the jaw and on which a gripping mechanism exerts a force which is multiplied by the lever. The gripping mechanism includes a sliding sleeve having an inner conical surface which produces the force on the collet levers via balls. This arrangement enables a smaller gripping spring to be used, or such spring to be omitted. The balls of the releasing mechanism are guided in helical slots having a flexible lateral strip which holds the gripping mechanism in position via a snap fit.

Abstract: A medical or dental handheld element has a rotatably arranged rotary part, at least one roller bearing for bearing support of the rotatably arranged rotary part, the roller bearing having at least one rotatable roller bearing part that is co-rotational with the rotary part and at least one stationary roller bearing part that is stationary in relation to the rotary part, and an anti-twist device or anti-rotation element provided to restrict the stationary roller bearing part from rotating. The anti-twist device comprises a polygonal, generally arc-shaped, open metallic anti-twist device. A handheld element with this anti-twist device is less sensitive to the effects of sterilization or cleaning processes. Also disclosed is a method for manufacturing such a handheld element.

Abstract: An angled dental shaft receptacle is provided for operating rotating instruments with an angled shaft. The angled shaft receptacle has a driver pin, and the driver pin is connected to the angled shaft of the instrument by a planar contact during operation. The rotating instrument is preferably a dental instrument.

Abstract: The invention relates to a medical or dental medical handpiece (3) having an elongate shaft (13), which has in its front end region a tool holder (5) having a lateral insertion opening (5a) for a tool (6), and having a rearward and a forward shaft section (13a, 13b) which include an obtuse angle (W2) which is open to the side away from the insertion opening (5a), wherein in the shaft sections (13a, 13b) there is rotatably mounted in each case a drive shaft section (53a, 53c), which stand in driving connection with one another by means of gears meshing with one another, and wherein the forward shaft section (13b) stands in driving connection with the tool holder (5) by means of gears (58, 59) meshing with one another.

Abstract: There is disclosed a medical handpiece, in particular a dental handpiece, having a lighting device which comprises at least one optical semiconductor element, whereby the at least one optical semiconductor element is arranged at least partially in the interior of the handpiece and is detachably connected to the handpiece. On account of this design, it is possible for the user to easily connect the handpiece to an optical semiconductor element that is needed for a certain treatment and has, for example, a certain desired power level and/or emits a desired wavelength. The handpiece may thus be used for different applications without requiring any additional components such as switches, etc., that take up space. The outside dimensions of the handpiece remain substantially unchanged in comparison with known handpieces.

Abstract: The stomatological tip comprises a head accommodating a turbine with a means for holding a stomatological instrument and at least one hole for gas admission to the turbine, a tip body having a socket for the head to receive, a gas admission duct communicating with a gas supply line. The socket for the hole is capable of providing a complete revolution of the head, while the means for holding a stomatological instrument appears as a collet holder having a control push-button. The tip is furnished with a valve, an intermediate duct provided in the head, an additional duct provided in the tip body and having its outlet communicating with the inlet of the intermediate duct, the clamping blades of the collet holder are accommodated inside the head and the control push-button is accommodated inside the head so as to perform reciprocating motion and have effect on the clamping blades of the collet holder.

Abstract: Operation of a handpiece is sensed, such as by detecting temperature and/or vibration associated with one or more of the bearing rings supporting the turbine in the handpiece. When operation exceeds a threshold, a visual or audible indication is provided, and power to the turbine may be interrupted. The sensor(s) may be built into the handpiece, or be part of a removable girdle placed on the handpiece. Typically, the handpiece is used for dental or medical applications.

Abstract: A retention system connects a dental instrument to a dental component and maintains contact between them during installation of the latter in the oral cavity. The instrument includes a shaft having a shaped driver bit at one end. The dental component includes a head configured to be engaged by the driver bit, a shank that extending outwardly away from the head and a plurality of threads thereon. In a first embodiment, the system includes a clip that is frictionally engaged with the shaft of the instrument and snap fitted to the head of the dental component. In a second embodiment, the system includes a vacuum source operationally connected to a passageway in the dental instrument. A vacuum is generated at the driver bit tip which retains the dental component on the instrument.

Abstract: At the front, a handpiece (1) has a clamp (10) fitted to tightly grip the shank of a removable tool housed in guide holes (23, 25). The clamp has two or more levers (26) attached to an annular section (22) of the clamp by elastic joints (27), each of which has a gripping jaw (20) to grip the tool shank. On each lever, the gripping jaw (20) is located much closer to the joint (27) than to a supporting surface, on which a tightening mechanism (17) exerts a centripetal force so that the lever multiplies this force. The tightening mechanism preferably has a sliding sleeve (40) having a conical inside surface (44), which produces the force at the levers of the clamp by means of balls (45) housed in the holes of a hollow rotatable shaft (11).

Abstract: The invention relates to a medical or dental-medical treatment which at its rearward end has a coupling element for coupling on to a matching coupling element of a flexible supply line, and in its forward region has a holder device for a tool, the handpiece being of a rearward and a forward handpiece section which are connected with one another by means of a plug-in connection and are fixed on one another by means of a latching device which has a latching arm extending approximately axis-parallel and which is transversely elastically bendable, which latching arm is arranged on the one plug-in connection part and is latched in its free end region with a latching element arranged on the other plug-in connection part . For the purpose of improving the connection between the rearward and the forward handpiece section the latching device at the same time axially fixes an insert part of the handpiece, which insert part sits in a plug-in recess of the one and/or of the other plug-in connection part.