Abstract: The contra-angle is provided with means for illuminating the site of treatment. The light source is incorporated inside the body of the contra-angle, and in front of this light source is inserted an optical element arranged to deflect the light rays towards the site of treatment. This optical element comprises a total reflection prism embedded in a recess in the body of the contra-angle.

Abstract: This contra-angle head of a dental handpiece comprises means for axially locking the dental instrument, in the form of a hollow guide member enclosing the upper portion of the driving pinion inside the head casing, this guide member being mounted for axial movement in the casing and rotating with the pinion by means of at least two wedge members disposed in the guide member and adapted to engage an annular groove of the dental instrument and to bear against the upper edge of this groove. A spring constantly urges the guide member away from the casing so that the instrument is pushed inwardly in the pinion by the wedge members for engagement with a shoulder formed in the pinion bore and acting as a stop means, the wedge members thus exerting a constant play take-up function.

Abstract: System of coupling of the head of a drive unit to the body of a driven unit, characterized in that, the head bears a longitudinal key having two slopes inclined in relation to the axis of the head, and the body has a guiding or key-way groove for this key, this groove opening on an annular clearing in which a segment can be rotated against a spring and in which a pin is fastened radially, so that, while the key is engaged, this pin, by cooperation with the first of the slopes controls the rotation of the segment, then by cooperation with the second slope controls the blocking of the head in its driving position, and the segment can also be operated by hand so as to free the pin and allow the withdrawal of the head by drawing the key rearwardly.

Abstract: The invention relates to a dental drill.According to the invention, the drill has a triple helicoidal flute and progressive pitch, the free spaces between the cutting lips increasing from the tip (3) toward the shank (1) of the drill.Application: dental apparatus.

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 precision injection system for intralignmental anesthesia and the like having a syringe with a tubular handle portion which is removably connected a tubular headpiece as a longitudinal extension thereof. The headpiece receives a carpule cartridge with injection contents monitored during injections through elongate windows on opposite sides of the headpiece. A dosing plunger housed in the handle portion in a retracted start position is activated by a servo-dosing lever and advances incrementally axially into the headpiece for delivery of metered quantities of the contents of the carpule cartridge each time the servo-dosing lever is actuated. Provision is made for semiautomatic resetting of the dosing plunger to a retracted start position by depressing a resetting key and raising the syringe to a generally vertically raised position.

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: A device for supplying luminous energy to a dental instrument to illuminate the area of treatment on a tooth being treated. The luminous energy is applied from a bulb housed in the device through an optical fiber extending through the dental instrument and having an end disposed for receiving the luminous energy from the bulb. Provision is made for energizing the bulb when the device is mounted on an electrical supply cable. A contact arrangement of two conductive studs disposed in a bore of an insulating sleeve and axially biased by a conductive spring to extend from the bore provides for making contact between the bulb and supply cable when the device is mounted on the supply cable. A section of the bore of the sleeve between the ends of the sleeve defines shoulders limiting the axial travel of the studs which have enlarged ends for engaging the shoulders.

Abstract: A hand-held implement for removing dental scale provided with a rigid shaft to which is applied vibrations in a rotational or circumferential direction by a dynamically unbalanced air driven turbine. The rotor of the turbine is coupled to the shaft by a bearing and the shaft is restrained from rotating and restrained axially. Provision is made for supplying cooling water through the shaft to a dental scale removing tool mounted on a free end of the vibrated shaft.

Abstract: This dental canal rotary instrument comprises a handle having a hollow metal sleeve surrounding concentrically the inoperative end of the instrument shank; a suitable plastic material is cast into a mold so as to fill the gap left between the sleeve and the shank to form a plastic core embedding the shank, the latter protruding from at least one of the sleeve ends; a notch is formed in the sleeve for anchoring the sleeve and the plastic core, and a flat face is provided on the embedded shank end, in order to improve the adherence of the sleeve, core and shank to one another.

Abstract: Device for high-speed coupling between a dentistry appliance and an element to which it is connected during use by the practitioner, characterised in that it comprises essentially:(a) a collar (6) truncated over at least one segment (7) and fixed to the dentistry appliance;(b) a ring (12) fixed to said element, the end (14) of which is recessed to form a female shape into which the profile of said collar can fit, the connection being obtained as a result of the positioning of the collar (6), after it has penetrated into said recess (14), in a groove (15) in the ring as a result of relative rotation of the collar and the ring.Application to the connection of dentistry articles.

Abstract: Device for fixing drill bits into the head of air motors for hand-held dentists' tools, of the type incorporating a clip in the rotor inside which the shank of the drill bit is inserted. The fixing clip (6) includes longitudinal slits (7) and is acted on at one of its ends by an elastic means which tends to close the head (10) of the clip (6) on to the drill shank by the cooperation of an inclined surface (11) formed on the head of the clip with a matching inclined surface (12) formed on the inside face of the rotor (2), the head of the air motor being further provided with means which allow the shank of the drill to be released, by compressing said elastic means.

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: Anaesthetic may be injected directly into the bone using a syringe in combination with a mechanism for causing the syringe needle to oscillate about its axis. The mechanism may be driven by a drive unit of the type conventionally used to power dental instruments.