Abstract: The invention concerns a device for locking a dental instrument having a rotating spindle, formed by a hollow spindle and adapted to receive the head of an instrument, and a locking spring formed by a lower ring extending on a common side by two branches or a plurality of elastic branches. Each branch is provided with a pin engaged in an annular groove provided in the head of the instrument. There is a push-button having, in its underside, a central conical pressure head adapted to space apart radially the branches of the locking spring to release the pins from the annular groove of the instrument. The locking branches are housed in the slots provided in the rotary spindle to lock in rotation the spring relative to the rotary spindle, the spring being moreover maintained axially between the push-button and a shoulder of the rotary spindle.

Abstract: Apparatus is disclosed for use in cleaning dental root canals using an endodontic file. The file is mounted in a drill head driven by an electric motor. The motor is normally driven in one, forward direction, but periodically, the motor rotation is reversed for a very short time. The duration of the motor reversal is so short that although the motor rotates in the reverse direction, the inertia and backlash in the transmission between the motor output shaft and the drill head is such that the direction of rotation of the file in the root canal is not changed.

Abstract: The invention relates to a contra-angle for implantology or surgery with a head for holding and rotating an instrument about its longitudinal axis, and a handpiece containing, in a non-limiting manner, a connection providing the connection with an external motor drive, and a reducing assembly with an output gear. The contra-angle is formed of removable subassemblies, and principally of a subassembly called the intermediate support, including an input gear meshing with the output gear of the reducing assembly and an end gear mounted on the same rotating shaft and inside a hollow cylindrical body. The intermediate support is mounted so as to slide freely along an axis inside a central part of a head body and enabling positioning in the head and rotational driving of a removable head cartridge, when all the subassemblies are mounted together to form the contra-angle.

Abstract: An instrument for reaming a root canal, in particular, in the apical zone, includes proximal portions for receiving a handle which allows the instrument to be used by hand or on the head of a dentist's contra-angle handpiece, and distal portions having a blade with a pointed tip of a known type. The active, cutting part of the blade has, from the pointed tip and continuing along the blade, two conical sections. In addition to the pointed tip, each of the conical sections has a greater conicity than the least distal part adjacent to it. The instrument is useful for reaming root canals using a sequence of instruments which avoid root weakening and the flow of filling material from the end of the canal.

Abstract: A catheterization device for preparing and filling a tooth endodontic cavity includes at least one root canal tool connected to a drive head. The tool is movable and has a base movably driven by the drive head about the reference axis of the base. A totally or partially eroded, filiform and elastic working part freely extends from the base and has an axis shifted in a parallel position with respect to the reference axis of the base.

Abstract: The invention concerns a device for locking a dental instrument having a rotating spindle, formed by a hollow spindle and adapted to receive the head of an instrument, and a locking spring formed by a lower ring extending on a common side by two branches or a plurality of elastic branches. Each branch is provided with a pin engaged in an annular groove provided in the head of the instrument. There is a push-button having, in its underside, a central conical pressure head adapted to space apart radially the branches of the locking spring to release the pins from the annular groove of the instrument. The locking branches are housed in the slots provided in the rotary spindle to lock in rotation the spring relative to the rotary spindle, the spring being moreover maintained axially between the push-button and a shoulder of the rotary spindle.

Abstract: The invention relates to a device for attaching instruments. The device includes a rotary shaft intended to accept the instrument and rotationally drive it. The device also has at least one peg that can be retracted elastically until it can fit into the latching groove, thus axially retaining the instrument. A catch rotates as one with the rotary shaft and, in combination with the rotary shaft, gives the shape combined with that of the driving flat of the shank of the instrument. There is the particular feature of retracting radially or longitudinally if the flat is correctly orientated and resuming the position in which it rotationally drives the instrument. The flat of the instrument generally adopts the appropriate position when turned as soon as the slightest rotational force is applied to it. The instrument is released by action on a push-button, which moves the peg aside or radially retracts it.

Abstract: An instrument for periodontal treatment includes a blade (1) which is integrally connected to a head (2). The head (2) can be coupled to a handpiece to impart a vibratory movement to the blade (1). The blade (1) has an active part (1 a) distributed along the blade (1) on a side defined by a plane passing through the axis of the blade (1). The center of the blade (1) is additionally provided with an irrigation channel (4) for receiving a liquid which opens out at the center of the active part (1 a) of the blade (1) along the major part of its length. This ensures, on the one hand, cleaning of the active part (1 a) of the tool during a procedure, and on the other hand, removal of the detached particles.

Abstract: Alternative methods are described for machining a root-canal instrument, such as a root-canal reamer, which includes a working section having three flutes forming three cutting lips which are located at the apices of an isosceles triangle.

Abstract: A mechanized dental instrument includes an active part (2) and a sleeve (3) arranged on an end of the dental instrument which opposes the active part. The sleeve (3) is provided with a rotary drive means (4) that can, when assembled with the head of a handpiece, directly engage with a rotary drive means located upstream of the head of the handpiece. The drive means (4) is produced from a flat metallic piece which is fixed to the active part (2) by being slid over the axle (2a) of the active part (2), and which is provided with at least one opening (5) that is shaped to enable the circulation of plastic material forming the sleeve (3) when the sleeve (3) is molded over the axle (2a) to ensure the connection of the rotary drive means (4) on the axle (2a).

Abstract: A driven appliance, such as a contra-angle handpiece for surgical instruments, in particular for dental surgery, includes a handle, a neck and a head for receiving an instrument. The handle and the neck of the contra-angle handpiece each receive a drive shaft, respectively, an input shaft and an output shaft, which are linked to each other by a gear train. The input shaft and the output shaft are slidingly mounted in their respective bodies, which forms a sheath for the two shafts. The shafts are maintained and supported on stops arranged on the corresponding sheathes through a single elastic element which is housed in the bend linking the handle to the neck.

Abstract: A container for packaging a plurality of endodontic instruments, and for laying out the endodontic instruments to indicate the preferred sequential use of the instruments by a practitioner, includes a case having a bottom, and a lid for enclosing the bottom of the container. The bottom includes a tray for receiving the endodontic instruments and a plurality of sequence markings which illustrate (for example, by color) progressive operating procedures for using sequences of the endodontic instruments. The lid is removed by the practitioner at the start of a treatment, and includes at least one counter which can be used to indicate the number of times a particular sequence of endodontic instruments has been used.

Abstract: A shank for a dental instrument, including instruments which are used in endodontics and in dental prophylaxis, is fitted on a contra-angle or a handpiece and is provided with a rotary drive which cooperates directly with the rotary transmission members of the kinematic chain of the contra-angle, upstream of the head of the contra-angle. Also, the head of a dental instrument which is equipped with such a shank.

Abstract: Dental reamers are manufactured from a cylindrical metallic blank (e.g., made of a nickel-titanium alloy) that is moved at a feed speed V.sub.A past a rotary grinding wheel whose disk, of variable diameter, determines a linear speed V.sub.L at which material is removed. The feed speed V.sub.A is greater than 91440 cm/min, while the linear speed V.sub.L is less than 7.62 cm/min.

Abstract: The present invention relates to a dental reamer (2) which tapers right down to its tip (1), of the type including helical slits which, on their sides, have cutting lips for boring out dental canals, in which the characteristics of the cutting conditions are defined by, on the one hand, a cutting angle .alpha. determined by the tangent to the cutting edge at the cutting point and the perpendicular to the surface to be cut at this point and, on the other hand, a clearance angle .beta. determined by the plane of the cutting surface and the tangent to the inactive face of the cutting edge, characterized in that the value of the cutting angle .alpha. is greater than or equal to zero and that of the clearance angle .beta. is greater than zero.

Abstract: A motor and handpiece assembly for driving a dental tool has a contra-angle and a motor. The contra-angle has a handle, a neck connected to the handle, and a head connected to the neck and adapted to hold the dental tool. The motor is adapted to drive the dental tool in different types of movement (e.g., continuous movement and alternating or vibratory movement). The invention provides a dental handpiece that can be used for different types of treatments using different types of dental tools that require different types of movement and different speeds.

Abstract: The sleeve has a cylindrical metal tube with a plastic core. The metal tube has one or more grooves on the inner surface of the tube that run along at least a portion of the length of the tube. The plastic core fills the annular space between the metal tube and the rod of a rotary dental instrument, such that plastic material (1) fills the grooves to anchor the plastic core to the metal sleeve and (2) is molded to rigidly link the rod to the sleeve. The present invention reduces the exposure of plastic material in the sleeve, thereby reducing plastic swelling that can occur when the dental instrument is repeatedly cleaned using disinfectants.

Abstract: A dental reamer having one or more cutting sections and one or more spiral grooves. The dental reamer has at least one cutting edge having a cutting point, characterized in that a tangent to the cutting point tends to superimpose itself on a tangent to a diameter of a circle in which the cutting sections are inscribed, wherein the diameter passes through the cutting point. The invention provides a reaming cut that, in a surprising manner, reduces or even eliminates the spiral displacement (i.e., uncontrolled advancement of the reamer) that results from rotation of the prior-art reamers, while still maintaining an excellent reaming efficacy.

Abstract: The invention relates to an instrument for periodontal treatment, consisting of a connection piece (4) and of a blade (1), wherein said blade (1) has an abrasive part exhibiting two sectors (10, 11) distributed along the blade, and each situated on opposite sides of a plane passing through the axis of the blade, these two sectors (10, 11) exhibiting different levels of abrasiveness such that when the instrument is introduced into the periodontal pocket during treatment, the more abrasive sector comes into contact with the root surface of the tooth, and the other, less abrasive, sector comes into contact with the mucosa, said instrument being adapted to be held by way of its connection piece (4) on a handpiece which confers a vibratory movement on it, allowing the two sectors (10, 11) to effect the detachment of the undesirable tartar.