Abstract: A head assembly for a medical handpiece includes a head housing and a rotor spindle contained in the housing. The spindle defines a longitudinal through-bore with an internal screw thread. An adjustable chuck is received within the through-bore of the spindle and has a complementary external screw thread adapted for mating with the internal thread of the spindle. The chuck has a top opening forming a keyway and a bottom opening adapted for receiving and holding a bur. A chuck key is attached to the housing, and includes a hand grip at its top end for being manipulated by a user and a chuck engaging bottom end. The chuck key is axially moveable between an operative position and an inoperative position. Upon rotation of the chuck key in the operative position, the chuck threadably moves relative to the spindle to an open position for receiving and removing the bur.

Abstract: Holding device for use with a tool for mechanical tightening of a screw connection in a bone-anchored dental implant without the tissue which surrounds the implant being stressed, the holding device having a first part which rotationally locks to the implant, an arm rigidly connected to the first part, and extending at essentially right angles from the first part, and an additional part engaging a stationary part of a tightening tool so that undesirable rotation movements are prevented during tightening of the screw connection. The additional part which engages the stationary part of the tightening tool during tightening of a screw connection is mounted pivotably on arm and additional part is pivoted relative to arm to allow release of the tightening tool from the holding device after tightening the screw connection.

Abstract: A handpiece having a releasable retaining device for a tool having a shaft about which the tool rotates. The handpiece has a housing and a drive sleeve rotatably mounted in the housing. The drive sleeve has a hollow cylindrical insertion hole into which the shaft of the tool is placed. A drive means is provided for rotation of the drive sleeve. First and/or second releasable couplings are provided for rotatably and/or axially connecting the shaft to the drive sleeve. The releasable couplings have either a coupling slider or pressure member which is displaceable between coupling and decoupling positions. An actuating device is provided for displacing the coupling slider or pressure member into their decoupling position. In one embodiment the coupling slider is made of a ceramic material and fabricated into its final form by means of a single fabrication process without after treatment.

Abstract: A centrifugal chuck for a surgical handpiece is adapted to automatically engage a surgical instrument so it may be driven by the handpiece. The centrifugal chuck comprises a pivotable trunnion body situated within a hollow drive shaft, the trunnion body having a throughbore coaxially aligned with the axis of the hollow drive shaft in order to receive the shaft of the surgical instrument. The trunnion body is secured to a pair of lever arms symmetrically situated about the exterior of the drive shaft, the lever arms extending in opposite proximal and distal directions from the pivotable attachment of the trunnion body to the drive shaft. Rotation of the drive shaft causes radially outward movement of the lever arms thereby misaligning the throughbore of the trunnion body relative to the drive shaft in order to frictionally engage the shaft of the surgical instrument.

Abstract: A dental instrument holder (10) comprises a clamping sleeve (28) having two cylindrical annular closed bearing regions (50, 52) axially spaced apart is arranged in the driven hollow shaft (22) accommodating the dental instrument. A spring-loaded clamping region (56) is located between these cylindrical bearing regions (52, 54), which clamping region preferably has two spring tongues (62, 64) partitioned by a U-shaped incision or indent (58, 60) from the clamping sleeve (28). The clamping sleeve (28) and the structural part (22) adjacent thereto may execute a relative axial movement between two positions: in the first, the clamping position, the elastically spring-loaded clamping region (56) of the clamping sleeve (28) is pressed radially inwards by a conical actuating surface (70) provided on the structural part (22).

Abstract: A dental handpiece for rotatably driving a dental tool includes a sheath housing a chuck which releasably holds the dental tool to the handpiece and a push button in operative contact with the chuck to operate the chuck to move the chuck between a looked and unlocked position. The push button is in the form of a ring which slides in a plane perpendicular to the axis of the sheath. The chuck includes a bur tube rotatably received in the sheath, a tilt plate which extends through side openings in the bur tube, and a tilt plate pusher which is received in the sheath and through which the bur tube extends. The tilt plate pusher has a side hole through which an arm of the tilt plate extends, such that movement of the tilt plate pusher will pivot the tilt plate. A head of the tilt plate pusher is in operative contact with the push button, such that when the push button is pressed, the tilt plate pusher will be moved forwardly to move the tilt plate from a locked to an unlocked position.

Abstract: A chucking device for a dental tool in a dental handpiece or angle head includes a clamping sleeve with resilient tongues. The resilient tongues of the clamping sleeve are arranged at a distance from each of the two ends of the clamping sleeve. On the side on which an actuating member for the resilient tongues is provided, the internal width of the clamping sleeve is greater than the external diameter of the tools to be used. The actuating member for the resilient tongues is an essentially tubular member whose external diameter corresponds to the internal width of the clamping sleeve and whose internal diameter corresponds to the external diameter of the tools to be used.

Abstract: In a handpiece (2) having a housing (3), a drive sleeve (7) mounted therein, into which drive sleeve a tool (9) can be inserted with its shaft (11) and which drive sleeve is mounted in the housing to be rotatable around its middle axis (9a) by a drive, a releasable coupling for rotational locking connection of the shaft (11) in the drive sleeve (7), and a releasable coupling for axial connection of the shaft (11) with the drive sleeve (7), whereby each coupling is formed by a coupling recess (18) in the shaft (7) and a coupling pin (19) on the drive sleeve (7) engaging in the coupling recess, the two couplings are formed by at least one common coupling recess (18) and the common coupling pin (19) is mounted to be moveable between a coupling position engaging in the coupling recess (18) and a decoupling position releasing the coupling recess (18) and is biased into its coupling position and against the shaft (11) by the force of a spring (34).

Abstract: A high speed dental handpiece turbine spindle assembly in which a generally cylindrical spindle is rotatably mounted within a housing for actuation by a supply of pressurized air acting upon turbine blades associated with the spindle. The spindle includes a longitudinal bore which accommodates a drill bit or bur, with one end of the spindle being tapered and threaded to fit a matching chuck nut. The spindle and chuck nut have interfering geometry so that the chuck nut cannot be inadvertently removed while changing drill bits, and so that the chuck nut cannot be inadvertently tightened so far that the spindle is permanently deformed.

Abstract: A dental handpiece includes a head, a tubular chuck having an open-end axial bore for receiving the shank of a dental bur and a tubular bur tube having an outer surface and an axial bore therethrough for receiving the chuck therein. The bur tube has at least one inner raceway formed integrally along its outer surface. An outer race having an outer raceway is associated with the inner raceway. A plurality of ball bearings are mounted between the raceways. A rotor may be formed integrally with the outer surface of the bur tube.

Abstract: A chuck mechanism for holding rotating tools in gear driven or turbine driven medical/dental devices. The chuck includes a bur tube which releasably receives a shaft of a dental tool, a tilt plate which extends through the bur tube and which has a hole through which the tool extends, and a tilt plate pusher which is moveable axially with respect to the bur tube. The tilt plate is moveable between a first, unlocked, position in which the edges of the tilt plate hole are spaced slightly from the dental tool shaft so that the shaft may be freely moved axially relative to the tilt plate, and a second, locked, position in which the tilt plate edges contact the shaft to prevent axial and rotational movement of the shaft relative to the tilt plate. The tilt plate is preferably spring biased to its locked position, and the tilt plate pusher is preferably operated by a push button to move the tilt plate to its open position.

Abstract: A dental handpiece contains a tool for dental treatment operation, tool holding members for detachably and rotatably holding the tool, tool detachment members for abutting against the tool holding members to detach the tool from the tool holding members, and rotatable contact members capable of being point-contacted with the tool holding members. The rotatable contact members when contacted with the tool holding members is rotatable with the tool holding members.

Abstract: A disposable hand tool of the compressed air drive type is disclosed for use in performing dental procedures on a workpiece. An elongated body has conduits penetrating a base at one end of the body. The conduits allow entry of a light beam, a pressurized water stream, and a compressed air stream into the body. The base includes attachment threads for securing the body to a source of the light beam, pressurized water stream, and compressed air stream. A plurality of passageways are in communication with the conduits for conducting the light beam, the water stream, and the air stream through the body. A head at the opposite end of the body contains bearings attached to a supporting shaft. The shaft includes a turbine impeller and a clamping hole for removable attachment of a dental bur to the shaft. The air stream drives the impeller at a high speed for rotating the bur about a rotational axis.

Abstract: A dental appliance having an elongated hollow body including a tubular handle and a tubular extension. The extension has at its forward end a recessed forward end formation defining a forwardly opening recess. A closure mates with the forward end formation on the recess on a mating plane generally transverse to the axis of the bore in the extension. The recessed forward end formation of the extension and the closure define a chamber at the forward end of the extension when the closure is applied. The bore in the extension is accessible from the forward end of the extension when the closure is away from the forward end of the extension for assembly of the appliance.

Abstract: A clamping arrangement for clamping a cylindrical shaft of a tool in a dental handpiece includes a clamping sleeve having resilient tongues for gripping the cylindrical shaft and being capable of being moved radially outward by an adjustable plunger to release the shaft. In order to achieve a largely wear-free tool guidance, the tool shaft is held at least at its distal end of the tool in a guide bushing, which is firmly joined to the hollow shaft. The guide contains an arrangement which enables axial mobility of the plunger, prevents twisting of the plunger so as to enable transmission of the force between the plunger and a manipulator which actuates the plunger.

Abstract: The cutting shank of an instrument to be received in the head of a contra-angle of a dentistry handpiece is clamped in position with a pushed-button control device which is displacable counter to a tensioning spring. The control device generally takes the form of at least one reversal element for receiving pressures responsive to movements of the push-button and for converting such movements into a traction movement exerted by the reversal element on the pusher which is used to control the collet chuck which receives the shank of the instrument.

Abstract: A chucking device for a dental handpiece includes a cutting tool, a collet having a plurality of slits to permit the cutting tool to be received and attached in position in the collet, a rotational sleeve for transmitting rotation to the collet, a locking member adapted to permit the diameter of the collet to be changed, and a coil spring thrusting the locking member along the inserting direction of the cutting tool. The outer periphery of the collet has a tapered surface adapted to be enlarged in diameter along the inserting direction of the cutting tool. The locking member is shifted along the tapered surface under the thrusting force of the coil spring to change the diameter of the collet to hold the cutting tool therein. When the locking member is pressed down against the coil spring, the locking member is then moved along the tapered surface in a direction opposite to the inserting direction of the cutting tool to release the cutting tool to permit the tool to be detached from the collet.

Abstract: A dental handpiece having a bur-receiving chuck with spring jaws which exert a strong clamping force on the shank of a bur for operatively securing the bur to the handpiece rotor, such handpiece also having a lever-actuated bur release mechanism for forcing the jaws apart when removal and replacement of a bur is desired. A force-multiplying control lever for camming open the clamping jaws is an integrated part of the handpiece assembly and is carried by a removable disk-shaped cover that may be rotated with respect to the head of the handpiece to position the lever at whatever radial direction the user prefers. A helical cup spring frictionally engages the cover to maintain the lever in its selected direction of operation, and at least one annular leaf spring bears against a cam portion of the control lever to hold the lever in a retracted or lowered position during operation of the handpiece.

Abstract: A dental burr has an axis of rotation and a cooling water passage extending therethrough in coaxial relation to the dental burr. The cooling water passage opens to a front end face of the dental burr, and this opening in the front end of the dental burr is disposed in an area including the axis of rotation of the dental burr. A dental handpiece for rotatably holding a dental burr includes a handgrip portion, a hollow head portion provided at a front end of the handgrip portion, and a cooling water passage. This cooling water passage extends along the handgrip portion,and opens at one end to a rear end of the handgrip portion while the other end thereof is connected to an internal space of the head portion. Part of the internal space serves as a passage for communicating the cooling water passage of the dental handpiece with the cooling water passage of the dental burr held by the dental handpiece.

Abstract: A chuck device for a dental handpiece includes a dental bur, a sleeve for accommodating and attaching the dental bur, a push button for detaching the dental bur, and a connecting-removal unit for removably holding and securing the dental bur within the sleeve. The connecting-removal unit includes an elastic engagement member normally engaging with an engaging projection of the dental bur for securing the dental bur within the sleeve, and an opening for accommodating the elastic engagement member within the sleeve or an upper sleeve portion for fitting the elastic engagement member on the outer side of the sleeve. The elastic engagement member has a slit and can be extended apart. When the push button is pushed downwards, the cam surface of the push button abuts on and extends the elastic engagement member apart to release the engagement between the elastic engagement member and the engaging projection of the dental bur to detach the dental bur from the sleeve.

Abstract: An apparatus and method for the supra and subgingival cleaning of teeth comprises and handle with a driving mechanism for reciprocally rotating a tapered cleaning tip about its longitudinal axis. A tuft or other scrubbing mechanism is provided on the outer circumference of the tip. The tip includes circumferentially disposed flutes which can be used to receive and dispense medication to the subgingival area. The tip is introduced into the gap between the gum and the tooth for scrubbing the outer surfaces of the tooth near and under the gum line. This effectively disrupts any bacteria plaque in these areas to clean the tooth.

Abstract: An ultrasonic toothbrush for use in personal dental hygiene care includes an exchangeable toothbrush member which is removably attached to an ultrasonic power member and may be readily removed therefrom with less than one revolution and inserted on to the ultrasonic power member in a like manner. Provision is made for locking the toothbrush to the power member and is arranged to transfer the ultrasonic energy from the power member to the toothbrush with minimum energy loss.

Abstract: A dental toolholder (2) has an endodontic filing tool (18) which is clamped in the toolholder so as to be secured against rotational and axial movements. A vibrating movement is impressed on the tool. The tool (18) can be clamped at its rear shaft end with a slight play and the vibrations can be imparted to the tool at its front shaft end (15). This part encloses the front shaft end (7b) with slight play and comprises a cylindrical recess whose cross-sectional shape has a constant-diameter configuration. Accordingly, the tool is set into a swinging movement perpendicular to its axis. The structural component part (15) rotates preferably at approximately 20,0000 rpm.

Abstract: An improved ultrasonic handpiece adapter for use in root canal procedures is provided in which a fire well is formed in the body of the device. The lower surface of the file well is frusto-conical in shape and receives a file wherein an enlarged file head has a frusto-conical shape at its bottom which seats against the lower surface of the file well when downward pressure is exerted on the file and which floats with respect to the lower surface of the file well when upward pressure is exerted on the file. A clutch mechanism is thereby provided wherein the file blade is in its engaged position during a cutting stroke and wherein the file blade floats during the motion of positioning the blade for the next cutting stroke. A cutting file has the tip of its shank flared so that the shank is prevented from being pulled through the file head. The apparatus may be connected to a conventional source of sub-sonic or ultrasonic power.

Abstract: A socket, which receives a tool having a cylindrical shaft and which is mounted for rotation to rotate the tool, has an outer sleeve which receives a clamping sleeve and a ram for engaging a first end of the clamping sleeve. The first end of the clamping sleeve is provided with slots defining resilient tongues which are moved from a clamping position radially outward to a position for releasing the shaft by engagement with the ram. The ram has either an outer conically tapered surface or partially conically outer tapered surfaces on projections which engage inner tapered surfaces of each of the tongues or fingers. Preferably, the tapers of the ram and fingers are selected so that only substantially a line contact is formed therebetween to reduce the force necessary to move the fingers or tongues radially outward to the declamping or disengaging position.

Abstract: A tool holder is furnished for fastening a dentistry-type tool to be subjected to vibrations. A core is attached to a generator of vibrations and includes a housing for a tool. A locking assembly cap having a rear end is fitted onto a forward area of the core. A locking assembly sliding component is placed over a rear area of the core for contacting the rear end of the core with front end of the locking assembly cap. A compressive spring engages the core and the locking assembly sliding component for pushing the locking assembly sliding component in a forward direction.

Abstract: A readily manipulatable fastening for a dental endodontic file and tip assembly for operation by ultrasonic vibrations. The fastening is compatible with a wide range of handpieces of different domestic and foreign manufacturers of dental instruments, and may be used interchangeably with ultrasonically operated scaling tips of various shapes and configurations, also catheters and other dental cleaning and scraping tools. A simple and rugged two-part unit consisting of a flow-through tip fastened to the outlet end of the vibratory stack and a completely enclosed housing for the outer end of the tip, other than a single small aperture therein, preferably bored at a small obtuse angle to the longitudinal axis of the tip for the shank of the file, permits a rapidly executed secure fastening or release of the shank from between the end of the tip and the internal end wall of the housing.

Abstract: An electric motor-driven drill has an irrigating tube for squirting water onto a drill bur. The tube has convolutions surrounding the motor for cooling the motor and warming the irrigating water. A quick-release chuck holds the bur shank coupled to the motor shaft.

Abstract: A clamping arrangement, especially for the clamping or gripping engagement of dental implements, consisting of a receiving sleeve which is rotatably supported in a handpiece and is connected with a rotary drive, which includes at least one rod-shaped elongated clamping element exerting a radially inwardly directed pressure against the shaft of the implement which is inserted into the receiving sleeve because of contact against an inclined track oriented perpendicular to the longitudinal axis of the clamping arrangement. The handpiece can pertain to a straight handpiece or to an angled handpiece (elbow) with an angled headpiece.

Abstract: A device for releasing a tool from a tool fastening mechanism of a dentist's handpiece comprises a push-piece that is held in an outer, inoperative position by a spring, and a slide mounted on a rotor of the dentist's handpiece. Upon being pressed, the push-piece engages the slide to release a tool fastened in the rotor. In order to prevent the push-piece from overheating when it is in contact with the slide while the slide is rotating at high speed, the push-piece carries a disc and the slide carries a ball. The disc and the ball are for instance made of sintered hard metal and are located where the push-piece and the slide engage such as to have substantially a point contact between them on the rotational axis of the slide.

Abstract: A tool holder preferably for an ultrasonic endodontic apparatus includes an eccentric member in the holder to secure the butt end of a tool thereon by a camming action during limited rotation of a cam member. The tool holder also includes an irrigating fluid passage located proximate to, but remote from, a tool-receiving bore in the tool holder to direct irrigating fluid onto the tool. An eccentric cam is mounted in a cross-bore within the tool holder, located relative to a tool-receiving bore having a predetermined longitudinal depth, so that a camming action of the eccentric cam longitudinally seats the tool deep in the bore while securing it there by the cam upon limited rotational motion of the cam. The cam includes tool pads for receiving mating surfaces of a bifurcated wrench.

Abstract: A tartar-removing or scaling handpiece, which is constituted of an elongated gripping sleeve, having arranged at one end thereof a tartar-removing or scaling implement which includes a bent operating end, wherein the gripping sleeve incorporates a light source arranged at the end thereof proximate the implement which is oriented towards the region of the tartar-removing implement, and which is located at one side adjacent the tartar-removing implement. The tartar-removing implement possesses a shaft connected with the gripping sleeve, to which there is joined the angled or curvilinearly bent operating end of the implement.

Abstract: A dental appliance has an elongated hollow tube within the interior of which is mounted for rotation an elongated drive shaft. One end of the tube is coupled to a handle as is the drive shaft which is driven from the handle in rotation. A head joined to the other end of the tube defines an interior cavity within which a hub is mounted for rotation about an axis disposed at an angle with respect to the drive shaft. Motion is translated from the drive shaft to the hub. An opening in the head enables the hub to be accessed through the opening. Included in the hub is a barrel section for securing a variety of dental attachments thereto. A seal is created between the opening from the cavity and the hub in order to prevent fluid flow therethrough. Lubricant is introduced within the tube and the drive shaft actuates an augar or the equivalent for propelling the lubricant into the motion translator.

Abstract: A screw (22) having the circumference of its head (23) toothed like a pinion firmly holds the cylindrical shank of a rotary tool in position in a slotted sleeve (17). A rack (25) on the front end of the hollow cylindrical spindle (24) meshes with the pinion or head (23) of the screw (22). The retraction or advance of the rack (25) is effected by a grooved ring (20) through screws (35,36) whose cylindrical heads are engaged in two helical guide slots provided in a nosepiece (19) and which are anchored in a pusher ring (28) indirectly applied against the rear face of the hollow cylindrical spindle (24).

Abstract: A system for maintaining in the head of a vibratable dental tool holder a dental tool releasably held axially in fixed position in a transverse passage oblique to the longitudinal axis of the dental tool holder. The system comprises a first sleeve axially of the dental tool holder having a leading edge bearing against the dental tool. A second sleeve is threaded on the dental tool holder and it keeps the first sleeve in close contact with the dental tool keeping it from moving axially away from the dental tool in response to vibration of the dental tool holder during operation.

Abstract: A clamping arrangement for the clamping engagement of implements, especially dental instruments, consisting of a mounting sleeve which is rotatably supported within a handpiece, and which is connected with a rotary drive, and which possesses clamping elements acting in a radially inward direction against the shank of the instrument which is inserted into the mounting sleeve. The handpiece can relate to a straight handpiece or an angled handpiece with an angle headpiece.

Abstract: A vibratory endodontic device is described for mechanical preparation of dental radicular canals, i.e., root canals, prior to their obturation. The device includes a housing, a vibratory drive means supported within the housing to minimize the transfer of vibration to the housing, an endodontic file connected to the drive means for vibratory movement and stop means operatively connected to the housing and substantially isolated from the mechanical vibrations created by the vibratory drive means. Additionally, fluid transport means are provided for maintaining a controllable or a continuous flow of irrigation fluid along the endodontic file. Various assemblies for retaining the endodontic files and the stop means at the operative end of the vibrating device are also described.

Abstract: A dental tool having a head with an output spindle to which are coupled dental treating devices such as a dental massaging brush. The output spindle is driven with a reciprocatory rotary motion imparted to it from a rotationally driven drive shaft coupled to the output spindle by a drive coupling device which converts the rotational motion of the drive shaft to reciprocatory rotary output of the output spindle. An O-ring effects a seal about the output spindle where it extends outwardly of the head. The drive coupling device has an eccentric stud fixed eccentrically to the drive shaft extending therefrom from one side to the other of a projection of the longitudinal axis of the drive shaft and making an angle with the projection of the axis. The eccentric stud is received in an axial slit in the output spindle for effecting the motion conversion.

Abstract: An endodontic unit comprising an elongated ultrasonic oscillating body having a tubular conduit extending beyond one end and provided with a weighted head on the outer end and in which a socket is formed and disposed at an obtuse angle to the axis of the body by means of providing a bend in the conduit intermediately of the ends thereof subtending an obtuse angle of greater magnitude than the obtuse angle of the socket, the weight of the head being adequate to damp the vibrations imposed upon an endodontic file, when mounted in the socket, to a degree sufficient to minimize the breakage of files and also induce in the files desired vibratory and oscillating movement to effect efficient operation in endodontic performance.

Abstract: A device for opening and closing a chuck for a dental handpiece has a handle portion and a powerhead assembly including a hollow driving shaft having, adjacent to its front end, a fowardly outwardly tapering portion joining a small diameter rear portion and a large diameter front portion. A hollow cylindrical chuck has a forwardly outwardly tapering outer peripheral surface joining a small diameter rear surface and a large diameter front surface corresponding to the respective driving shaft portions. The chuck is slidably inserted into the driving shaft. Three radial openings are formed at equally spaced positions in the forwardly outwardly tapering outer peripheral surface of the cylindrical chuck. A disc-shaped chucking die is slidably fitted into each radial opening to hold a dental tool. A chuck pusher is held in a socket with a disc plate spring interposed between the socket and the chuck pusher, and the pusher is movable for axially displacing the chuck to hold or release the dental tool.

Abstract: A chuck device for a dental handpiece comprising fixedly mounting a front collar inside a rotor at the end thereof for the dental handpiece and threadedly and detachably fixing a cartridge chuck behind said front collar inside of said rotor, said cartridge chuck comprising a substantially cylindrical chuck case provided at the rear end with an engagement portion for detachably connecting a cutting tool thereto, a synthetic rubber chuck body press inserted into the end side of said case, and a rear collar fixedly mounted behind said chuck body inside said case.

Abstract: A dental handpiece has a hollow main body enclosing a central rotating spindle equipped with tool grip means adjacent its forward end; spring means effects axial movement of the spindle in an inward direction for actuating the tool grip means to provide a gripping function and release means moves the spindle outwardly against the bias of the spring means for deactivating the tool grip means with the release means including a unitary plate removably mounted in the main body with first and second levers being pivotally mounted on opposite sides of the plate so as to be substantially positioned within the confines of the main body; driving ends of the levers are engageable with the spindle for moving the spindle axially outwardly of the main body to deactivate the grip means. The levers are on diametrically opposite sides of the axis of the handpiece and are mounted for pivotal movement in a plane passing through the axis of the hand instrument.

Abstract: A collet of somewhat flexible plastic for holding a dental tool in a dental handpiece, has an inner body which fits within a socket in the burr tube of the handpiece, and at its outer end extends outwardly into a hub and then rearwardly into a cylindrical skirt which fits between the outer surface of the bearing for the burr tube and the inner surface of a counterbore in the handpiece. Centrifugal force caused by rotation of the burr tube flares the skirt outwardly against the counterbore surface to provide a seal therebetween. In a modification the skirt slants outwardly to contact the counterbore surface when the skirt is stationary. A modified skirt tapers from its connection to the hub to the skirt end.In another modification, the collet has a bore in its inner end, with the handpiece end cap, the driven gear and the burr tube having bores aligned with the collet bore so that a burr extractor pin can extend through the bores to push the dental tool out of the collet.

Abstract: This fixing device comprises a clamping claw consisting of a pair of diametrally opposed semi-cylindrical curved shells each connected by means of a small bar parallel to the shell generatrices to an end pivot pin, the bars extending on either side of the shells. An axial bore is formed through the claw and the pair of pivot pins are provided, in the vicinity of their junction with the corresponding bars, with a circular land having a diameter at least substantially equal to that of the shells, a cylindrical sleeve of flexible and sterilization-resistant material being slipped over these lands and extending therebetween in order to impart the necessary fluid-tightness to the axial bore in relation to the interior of the handpiece.

Abstract: This device for locking a dental tool in a handpiece of the contra-angle type comprises a keeper plate slidably mounted on the external surface of the holder and rigidly associated with a control member formed with a thumb-piece consisting of an inclined surface portion thereof. A keyhole formed in the keeper plate is engaged by a suitable shaped end portion of the tool shank so that when the keeper plate is moved to its release position the tool shank can pass through the larger portion of the keyhole and when the plate is in its locking position to which it is urged by a return spring the end portion of the tool shank engages the narrow portion of the keyhole.

Abstract: A twist-lock pin for improving the retention and resistance characteristics of plastic dental restorative materials and a wrench for providing positive control over the pin during insertion into the opening in the tooth. The pin is partially screwed counter-clockwise into a left-hand threaded metal cylinder, the wrench body. After two revolutions, the pin bottoms out against a flat ended, right-hand limiting screw which is inserted clockwise from the opposite end of the wrench body and which is limited by two lands, one a flat area in the wall of the wrench body and the other at the end of the wrench body. After the wrench has been utilized to insert the pin into the tooth structure, it is removed by relieving the pressure on the pin and unscrewing the wrench from the pin.

Abstract: A device of this invention for opening and closing a chuck for a dental handpiece comprises a housing and an output shaft rotatably journalled in the housing. A cylindrical hollow is formed axially from a top end portion into the output shaft and a plurality of openings are formed at equally spaced portions around said shaft near an innermost portion of the hollow. A truncated cone-shaped column having a conical surface is firmly inserted into the innermost hollow of the output shaft to define a space for a small metallic driving ball. The small driving ball is rotatably inserted into each opening of said output shaft, and a large metallic driven ball is rotatably inserted into the hollow to abut against these small driving balls. A ball control sleeve having a tapering inner periphery is slidably fitted on the output shaft to locate at the openings.

Abstract: .Iadd.A dental handpiece comprises an air driven turbine rotor provided with a chuck to removably hold a dental bur and rotate it at extremely high speed. The rotor is mounted on anti-friction bearings within a capsule which is removably received within a housing to permit replacement of the capsule and turbine as a unit. The fluid outlet from the turbine is restricted sufficiently to ensure that a portion of the fluid is exhausted through the bearings and openings in the housing to prevent egress of foreign matter into the interior. .Iaddend.

Abstract: A dental appliance having an elongated hollow body including a tubular handle and a tubular extension. The extension has at its forward end a recessed forward end formation defining a forwardly opening recess. A closure mates with the forward end formation on the recess on a mating plane generally transverse to the axis of the bore in the extension. The recessed forward end formation of the extension and the closure define a chamber at the forward end of the extension when the closure is applied. The bore in the extension is accessible from the forward end of the extension when the closure is away from the forward end of the extension for assembly of the appliance.

Abstract: A dental toolholder (2) has an endodontic filing tool (18) which is clamped in the toolholder so as to be secured against rotational and axial movements. A vibrating movement is impressed on the tool. The tool (18) can be clamped at its rear shaft end with a slight play and the vibrations can be imparted to the tool at its front shaft end (15). This part encloses the front shaft end (7b) with slight play and comprises a cylindrical recess whose cross-sectional shape has a constant-diameter configuration. Accordingly, the tool is set into a swinging movement perpendicular to its axis. The structural component part (15) rotates preferably at approximately 20,000 rpm.