Abstract: An endodontic instrument which comprises an elongate shank which has a tapered working length adjacent the pilot end, and at least one continuous helical flute formed along the tapered working length so as to define sharp cutting edges along the sides of the flutes. Also, at least one relief, in the form of a flat surface, extends axially along a substantial portion of the length of the working length, which acts to reduce the tendency of the tapered working length to screw into and crack the tooth during manipulation thereof by the dentist in the course of root canal therapy.

Abstract: A method of fabricating an endodontic instrument by a machining operation is disclosed, and wherein a wire-like rod composed of a titanium alloy is advanced past a rotating grinding wheel at a relatively slow feed rate, with a sufficient depth of cut to remove all of the material on a given surface without over grinding a previously ground surface, and with the grinding wheel rotating at a relatively slow surface speed. The disclosed method is able to efficiently produce endodontic instruments having a high degree of flexibility, high resistance to torsional breakage, and with sharp cutting edges along the working length.

Abstract: A portable holder for safely supporting a plurality of sharp dental instruments, and which comprises a body member which includes a base plate having a plurality of openings therein for supportingly receiving the instruments. A pressure plate is slideably mounted to the body member immediately below the base plate, and the pressure plate includes a plurality of openings which are aligned with the openings of the base plate and are adapted to receive the shanks of the instruments which are supported in the openings of the base plate. The pressure plate is mounted for slidable movement between a loading position wherein the openings of the base plate and the pressure plate are aligned, and an instrument retaining position wherein the openings are offset so that the instruments are engaged and lock in the openings.

Abstract: An endodontic instrument which comprises an elongate shank which has a tapered working length adjacent the pilot end, and at least two continuous helical flutes formed along the tapered working length. The flutes are non-uniformly separated in the axial direction, and they define a relatively broad helical land and at least one relatively narrow helical surface. In one embodiment, the helical surface is a relatively narrow helical land and in another embodiment, the helical surface is a sharp helical edge.

Abstract: A method of fabricating an endodontic instrument by a machining operation is disclosed, and wherein a wire-like rod composed of a titanium alloy is advanced past a rotating grinding wheel at a relatively slow feed rate, with a sufficient depth of cut to remove all of the material on a given surface without over grinding a previously ground surface, and with the grinding wheel rotating at a relatively slow surface speed. The disclosed method is able to efficiently produce endodontic instruments having a high degree of flexibility, high resistance to torsional breakage, and with sharp cutting edges along the working length.

Abstract: A kit of endodontic instruments which are adapted for use in performing root canal therapy, and wherein the instruments in the kit have increasing diameters and differing tapers. The instruments are designed to be used sequentially in root canal therapy, and the difference of the tapers serves to prevent the whole working length of the instruments from being engaged with the wall of the tapered canal being formed, to thereby reduce the frictional loading of the instruments and the risk of breakage.

Abstract: A method of fabricating an endodontic instrument by a machining operation is disclosed, and wherein a wire-like rod composed of a titanium alloy is advanced past a rotating grinding wheel at a relatively slow feed rate, with a sufficient depth of cut to remove all of the material on a given surface without over grinding a previously ground surface, and with the grinding wheel rotating at a relatively slow surface speed. The disclosed method is able to efficiently produce endodontic instruments having a high degree of flexibility, high resistance to torsional breakage, and with sharp cutting edges along the working length.

Abstract: A dental hand instrument, such as an explorer, which comprises an elongate rigid handle, and an elongate highly flexible blade attached to one or both ends of the handle. The blade is curved and/or bent along its length and is composed of nickel-titanium alloy, which provides a high degree of flexibility and wear resistance. The high degree of flexibility has been found to significantly enhance the tactile feedback to the hand of the dentist, so that the dentist is able to recognize and distinguish surface cracks, areas of decay, and the like as the point is moved across the exterior surface of a tooth.

Abstract: A kit of endodontic instruments for use in root canal therapy wherein each instrument comprises an elongate blade having a proximate end and an opposite distal end, and with the blades of the instruments in the kit respectively having progressively increasing tapers. The kit is employed to fill an extirpated root canal with gutta percha, and instruments of progressively increasing taper are used in sequence during the obturation procedure so as to control the compaction of the gutta percha points in the canal.

Abstract: A method of fabricating an endodontic instrument by a machining operation is disclosed, and wherein a wire-like rod composed of a titanium alloy is advanced past a rotating grinding wheel at a relatively slow feed rate, with a sufficient depth of cut to remove all of the material on a given surface without over grinding a previously ground surface, and with the grinding wheel rotating at a relatively slow surface speed. The disclosed method is able to efficiently produce endodontic instruments having a high degree of flexibility, high resistance to torsional breakage, and with sharp cutting edges along the working length.

Abstract: A method of fabricating an endodontic instrument by a machining operation is disclosed, and wherein a wire-like rod composed of a titanium alloy is advanced past a rotating grinding wheel at a relatively slow feed rate, with a sufficient depth of cut to remove all of the material on a given surface without over grinding a previously ground surface, and with the grinding wheel rotating at a relatively slow surface speed. The disclosed method is able to efficiently produce endodontic instruments having a high degree of flexibility, high resistance to torsional breakage, and with sharp cutting edges along the working length.

Abstract: An endodontic instrument for use in root canal therapy which comprises an inner core of a metal having a specific flexibility, and at least one outer shell of a metal having a different flexibility. By selecting the ratio of the two metals, the instrument may be designed to have a predetermined desired flexibility which is sufficient to assure proper operation of the instrument, yet not so stiff as to risk damage to the tooth canal. A kit which is composed of several such instruments of increasing diameter is also disclosed, and with the instruments being designed to be used sequentially in root canal therapy, and wherein all of the instruments possess substantially the same degree of flexibility. The instruments can thus be used with predictable and consistent results.

Abstract: An endodontic procedure is disclosed which involves extirpating a root canal of a tooth, and then inserting a machine driven compactor which is coated with alpha phase gutta percha into the extirpated canal. The compactor is then rotated at a relatively high speed and so that the alpha phase gutta percha is plasticized solely by the frictional heat generated by the rotating compactor. The plasticized gutta percha is thrown radially outwardly, and pushed downwardly, so as to fill all of the voids of the canal, and the compactor is then withdrawn and the gutta percha cools and solidifies. A crown may be then fitted to the tooth above the gutta percha in the conventional manner.

Abstract: An endodontic instrument is disclosed which comprises an elongate shank having a lower working length. One or more helical flutes are positioned on the working length, and the bottoms of the flutes define a solid core which is cylindrical in one embodiment, and reversely tapered in another embodiment. The solid core permits the working length to permanently twist upon becoming locked in the canal during root canal therapy, and the twists move upwardly from the point of locking engagement until they may be visually and/or tactilely noted by the dentist, and so that the dentist is alerted before breakage occurs.

Abstract: A dental instrument adapted to be used as a dental file and dental reamer for removing dead or damaged tissue from the root canal of a tooth. The dental compactor instrument is formed with a tapered shank having at least two helical flutes defining at least two continuous helical cutting edges. A helical peripheral land extends between the helical flutes at the periphery of the shank. The cutting edges have a neutral rake angle.

Abstract: A dental instrument adapted to be used as a dental compactor for condensing a thermoplastic material in the extirpated root canal of a tooth. The dental compactor instrument is formed with a tapered shank or working portion having at least two helical flutes defining at least two continuous helical shoulders. A helical peripheral land extends between adjacent helical flutes at the periphery of the shank. The shoulders have a neutral rake angle at the periphery of the shank.

Abstract: The specification discloses a micro drill with a modified point in which the drill is formed from a rigid cylinder and has two opposed helical wings and helical edges. Each wing has an undercut leading surface to provide a positive rake angle at the helical edges of the wings, and the two wings have a smooth "S" shaped cross-section. Two opposed flanks are formed by an inclined cut in each of the wings providing the drill point with a somewhat V-shape, and a leading corner is defined on each of the wings at the intersection of the helical edge and the flanks. A cut is provided in each of the leading surfaces adjacent to and below the flanks thereby forming a cutting edge on the drill point with an increased positive cutting action. The drill may be cut so that an under-surface is formed immediately below each flank and its cutting edge and so that a side surface is formed in the wings in an orientation perpendicular to the under-surface.

Abstract: A dental reamer adapted for removing damaged nerve tissue and dead or injured cell material from the root canal of a tooth is formed with a tapered shank with at least two oppositely disposed continuous helical flutes formed along at least a part of its shank to define two oppositely disposed continuous helical upwardly facing cutting edges.

Abstract: A dental instrument adapted to be used as a dental compactor for condensing a thermoplastic material in the extirpated root canal of a tooth. The dental compactor instrument is formed with a tapered shank or working portion having at least two helical flutes defining at least two continuous helical shoulders. A helical peripheral land extends between adjacent helical flutes at the periphery of the shank. The shoulders have a neutral rake angle at the periphery of the shank.