Abstract: A medical bladed device is provided containing a handle and a cutting blade portion which is tapered and formed in continuation from the handle and having first and second faces on a front face, and third and fourth faces on a back face with a pair of primary cutting blades, each formed on both sides thereof, and a pair of secondary cutting blades, each formed on both sides thereof, the cutting blade having a sharp tip and being formed with a triangular cross section by forming a fifth face diagonally crossing from the front face of the cutting blade portion to the back face of the cutting blade portion. A secondary cutting blade angle is formed by the pair of secondary cutting blades ranging from 35 to 105 degrees, and a primary cutting blade angle is formed by an imaginary intersecting point between the pair of primary cutting blades ranging from 15 degrees to 35 degrees.

Abstract: A dental handpiece stably cutting a wall of a root canal without a fear of piercing a root opening. The dental handpiece includes a means for holding a tool cutting a tooth to be cured and a support for setting the cutting tool at a desired position relative to the tooth to be cured. The length of the support may be changeable by stages. The holding means may be formed of a head of the dental handpiece and a plurality of supports with different lengths may be removably mounted to the head. The support can stand on a head of the dental handpiece and the length from the head is changeable. The support is formed separately from the dental handpiece to be removable, and may have a stopper which abut with a tooth to be cured or an appropriate portion near the tooth.

Abstract: A dental handpiece to securely detect the load applied to the handpiece itself, and when an excessive load is applied to the handpiece, the cutting operation is suspended. The dental handpiece includes: a head; a support mounted in the head to support a cutting tool; and a transmission mounted in the head to transmit driving force to the support. The support and the transmission are slidably connected with each other. In the dental handpiece, the support may be cylindrical and can be provided with a plurality of inclined projections that are arranged in a longitudinal direction of an outer periphery of the cylinder; the transmission may be provided with engaging projections with inclined faces parallel to inclined faces of the plurality of inclined projections; and the transmission can be provided with resiliency that allows the engaging projections movable in a direction departing from the inclined projections.

Abstract: A stent manufactured for treating internal tubular organs, typically for treating a blood vessel, in which the stent has a sufficient diametral shrinkage ability and an ability for returning back to the original diameter thereof. A zigzag shape-memorized stent A is manufactured by performing shape memorization where a wire 1 is fixed in a zigzag bent manner in which the wire is made from a shape-memorizing Ni—Ti alloy not having been subject to shape-memorization of any sort. A stent A being shape-memorized with a zigzag shape as well as a cylindrical shape could be manufactured by performing shape-memorization process in which a stent having been shape-memorized into a zigzag shape with the end portions thereof being connected by overlapping with each other, is attached to a cylindrical jig.

Abstract: The present invention relates to a medical scalpel for incising a spherical biological tissue comprising a shank and a planar blade portion integrated with the shank. The planar blade portion has a first face and a second face opposed in parallel as a whole with each other. The planar blade portion has a pointed end to thereby show a reverse-V profile and has, on both sides of such pointed end, an edge in parallel as a whole with the first face and the second face, the blade portion being formed so as to have a ratio of the partial thickness thereof on one side of a virtual flat plane surrounded by said edge to the total thickness thereof within a range of from 75 to 93%.

Abstract: A dental instrument for root canal therapy having a shaft portion and an operational portion extended from such shaft portion, wherein at least a region from the tip of the operational portion down to a predetermined distant position has a sectional form surrounded by an arc and a chord, and a length of a line segment along a vertical bisector of the chord sectioned between such chord and such arc equals to or longer than five-eighths of the diameter of a virtual circle composed by such arc was disclosed.

Abstract: This invention relates to a dental reamer used in dental treatment for forming a root canal, in which the dental reamer prevents digging into a root canal wall and deviation even when attached to a handpiece and driven by an engine. With this reamer, a spiral working portion is formed by grinding and cutting away a tapered rod with two oppositely faced lines, and then, the ground material left with two arcs and a center of a circle is inserted into a molding space comprised of a pair of holding jigs and support jigs to perform the twist-process. In association with the twist-process, a cutting portion and a flank portion are formed on both ends of the working portion.

Abstract: The present invention relates to a dental root canal therapeutic instrument comprising: a shaft portion and a work portion made of spiral projections in continuation with the shaft portion. A cross section of the projections of the work portion is formed of a set of long sides and a set of short sides and is composed of a parallelogram constituted of a set of acute angle edges and a set of obtuse angle edges, wherein the acute angle edges among the acute angle edges and the obtuse angle edges, which form the projections, are placed on a side of the shaft on the side face of the work portion, and wherein a tip of the acute angle edge is located at a further position with respect to a center axis of the work portion than a position of a tip of the obtuse angle edge.

Abstract: A dental instrument support mechanism for establishing stable support for dental instruments such as a dental cutting tool, a drill, a fiber scope and the like. The dental instrument support mechanism is formed with a base portion, and a support arm connected to the base portion at one end for holding a dental instrument at another end. The dental instrument held by the support arm is fixedly maintained a positional relationship with a dental object in an oral cavity of a patient. The dental instrument support mechanism is attached to one of a head, face, jaw, tooth of the patient or a treatment bed.

Abstract: A contra-angle dental handpiece is capable of rotating a cutting tool in the forward direction when the cutting tool is in the most advanced position in a root canal of a tooth and preventing the reverse rotation of the cutting tool when the cutting tool is retracted therefrom. The contra-angle dental handpiece includes a rotation shaft for rotating a dental cutting tool about a rotation axis, a drive shaft for rotating the rotation shaft, and a drive mechanism for driving the dental cutting tool in a backward and forward direction of the rotation axis and for intermittently rotating the dental cutting tool only in the forward rotational direction about the rotation axis when the cutting tool is at around a most advanced position in a root canal of a tooth.

Abstract: A needle holder for guiding a surgical needle having a suture attached to the needle, in which the surgical needle is transferred from a first shaft to a second shaft, comprising a needle stand formed on the first shaft and a needle receiver formed on the second shaft, receiving the needle made upright at the needle stand. Further, the needle holder comprises a guide passage formed on the first shaft for guiding the suture attached to the needle from the needle stand in a prescribed direction to at least the vicinity of the needle stand, the guide passage having a surface that has no edge damaging the suture in a cross direction with respect to the direction of the tension exerted to the suture.

Abstract: The present invention relates to a suturing needle for medical use comprising a needle tip portion for piercing a body tissue, a distal end portion for coupling a suture and a body portion formed between the needle tip portion and the distal end portion The body portion is constituted of a pair of flat surfaces opposing to each other and a pair of grooves opposing to each other in a direction intersecting with the opposing direction of the flat surfaces.

Abstract: A dental instrument for root canal therapy having a shaft portion and an operational portion extended from such shaft portion, wherein at least a region from the tip of the operational portion down to a predetermined distant position has a sectional form surrounded by an arc and a chord, and a length of a line segment along a vertical bisector of the chord sectioned between such chord and such arc equals to or longer than five-eighths of the diameter of a virtual circle composed by such arc was disclosed.

Abstract: The present invention relates to a dental root canal therapeutic instrument comprising: a shaft portion and a work portion made of spiral projections in continuation with the shaft portion. A cross section of the projections of the work portion is formed of a set of long sides and a set of short sides and is composed of a parallelogram constituted of a set of acute angle edges and a set of obtuse angle edges, wherein the acute angle edges among the acute angle edges and the obtuse angle edges, which form the projections, are placed on a side of the shaft on the side face of the work portion, and wherein a tip of the acute angle edge is located at a further position with respect to a center axis of the work portion than a position of a tip of the obtuse angle edge.

Abstract: A suture needle has a unique structure for reducing impalement resistance. The suture needle is formed with a base end portion formed at an end of the suture needle for engaging a suture thread, a tip portion formed at another end of the suture needle for impaling a tissue, and a tapered portion extending to the tip portion. The tapered portion has a cross-section without a cutting edge and a plurality of roughened regions formed in stripes extending in a substantially axial direction of the tapered portion. The roughened regions are provided solely on the tapered portion of the suture needle. The surface roughness of the roughened regions on the suture needle is about 2 &mgr;m-15 &mgr;m.

Abstract: A suture ligating device used in a endoscopic surgery which can reliably transfer a knot of a suture formed outside a human body to inner tissues to be ligated inside the human body without causing a separation of the knot from the suture ligating device. The suture ligating device includes a manipulation portion, first and second rod members provided at the manipulation portion and making a relative movement in response to an operation of the manipulation portion, first and second top end members provided at an end of the first rod member, concaves formed at the ends of the first and second top end members, and the third top end member provided at an end of the second rod member to perform an open and close movement in response to the relative movement of the first and second rod members.

Abstract: Present invention relates to an endodontic instrument comprising a shaft and a work portion connecting to the shaft. The work portion has a plurality of helically extending blades to form a rectangular cross section in which the opposite edges of one set are longer edges and the opposite edges of the other set are shorter edges, the work portion having each apex of a right angle.

Abstract: An object of the present invention is to provide a safe surgical needle apparatus, and a surgical needle and a needle holder used therein, which can prevent the medical participants from being erroneously punctured with a tip end of the surgical needle and can permit a smooth tissue penetration of the surgical needle only when performing a suturing work.

Abstract: The present invention provides a surgical needle having a needle tip end and a clamping portion to be clamped by a needle holder for applying a current, whereinthe needle tip end is made from a conductive material which is electrically connected to a conductive material of the clamping portion,an insulating layer is provided over the clamping portion and a tip surrounding portion of the surgical needle, whereas at least the needle tip end is electrically exposed, andwhen the insulating material over the clamping portion is clamped by the needle holder, the conductive material of the clamping portion is electrically connected to the needle holder.