Abstract: Method of producing a medical cutting tool and a medical cutting tool that will not rust and that is capable of stably demonstrating high strength. A working section formed by a cemented carbide or ceramic is brazed to the tip of a shank part formed by a round bar-shaped austenitic stainless steel, thereby constituting a cutting tool. The shank part includes a shank, a neck, and a joint to which the working section is brazed. At least part of the stainless steel near the joint of the neck and in the joint has a fiber-like structure. The structure of the stainless steel in the joint on the working section side has a granular structure.

Abstract: A method of producing a medical cutting instrument. Medical cutting instrument is provided which stably exhibits high joint strength obtained by brazing. Cutting instrument is configured by providing a working section to a front end of a shank section. Working section consists of a carbide or a ceramic, shank section being constructed from round stainless steel bar or round tool steel bar. Shank section and working section are connected through a brazed section. Brazed section is portion at which shank section and working section are brazed together while brazing surfaces, which are provided with protrusion sections formed on shank section and/or working section, are caused to be in contact with each other. Protrusion sections each have sloped surfaces having an apex, and the height of the sloped surfaces is set in range of 0.5%-8%, inclusive, of the diameter of the brazing surface of the shank section.

Abstract: Method of producing a medical cutting tool and a medical cutting tool that will not rust and that is capable of stably demonstrating high strength. A working section formed by a cemented carbide or ceramic is brazed to the tip of a shank part formed by a round bar-shaped austenitic stainless steel, thereby constituting a cutting tool. The shank part includes a shank, a neck, and a joint to which the working section is brazed. At least part of the stainless steel near the joint of the neck and in the joint has a fiber-like structure. The structure of the stainless steel in the joint on the working section side has a granular structure.

Abstract: A method of producing a medical cutting instrument. Medical cutting instrument is provided which stably exhibits high joint strength obtained by brazing. Cutting instrument is configured by providing a working section to a front end of a shank section. Working section consists of a carbide or a ceramic, shank section being constructed from round stainless steel bar or round tool steel bar. Shank section and working section are connected through a brazed section. Brazed section is portion at which shank section and working section are brazed together while brazing surfaces, which are provided with protrusion sections formed on shank section and/or working section, are caused to be in contact with each other. Protrusion sections each have sloped surfaces having an apex, and the height of the sloped surfaces is set in range of 0.5%-8%, inclusive, of the diameter of the brazing surface of the shank section.

Abstract: A medical cutting instrument which stably exhibits high joint strength obtained by brazing. A cutting instrument (A) is configured by providing a working section (2) to the front end of a shank section (1), the working section (2) consisting of a carbide or a ceramic, the shank section (1) being constructed from a round stainless steel bar or a round tool steel bar. The shank section (1) and the working section (2) are connected through a brazed section (3). The brazed section (3) is the portion at which the shank section (1) and the working section (2) are brazed together while brazing surfaces, which are provided with protrusion sections formed on the shank section (1) and/or the working section (2), are caused to be in contact with each other. The protrusion sections provided on the brazing surfaces each comprise sloped surfaces (5b) having an apex (5a), and the height of the sloped surfaces (5b) is set in the range of 0.5%-8%, inclusive, of the diameter of the brazing surface of the shank section (1).

Abstract: [Problem] To provide a method for manufacturing a medical cutting tool and a medical cutting tool that will not rust and that is capable of stably demonstrating high strength. [Solution] A working section (2) formed by a cemented carbide or ceramic is brazed to the tip of a shank part (1) formed by a round bar-shaped austenitic stainless steel, thereby constituting a cutting tool (A). The shank part (1) comprises a shank (1a), a neck (1b), and a joint (1c) to which the working section (2) is brazed. At least part of the stainless steel near the joint (1c) of the neck (11b) and in the joint (1c) has a fiber-like structure. The structure of the stainless steel in the joint (1c) on the working section (2) side has a granular structure.

Abstract: A stainless steel bur, which can cut minute depressions etc. and even healthy dentin when necessary, allowing a technician to detect when cutting the healthy dentin is provided. It includes a removable handle (11) connected to a hand piece on the base side, a working section (12) to which a cutting blade for cutting teeth is attached to the tip, and the working section and the handle are connected to a tapered intermediate section (13). This steel bur is formed into a fiber structure by hardening austenitic stainless steel through wire drawing. Since the tapered part bends and generates vibrations when the working section is rotated to cut healthy dentin, it can be understood that the healthy dentin is being cut, and excessive cutting may be prevented. Alternatively, excessive cutting may be prevented by processing from the maximum diameter of the working section to the tip thereof through etching or the like to round cutting blade edge and make a blunt edge.

Abstract: A medical cutting tool manufacturing apparatus, which can form cutting blades to the top face with a simple structure, and a manufacturing method for the same are provided. The medical cutting tool manufacturing apparatus of the present invention, which manufactures a medical cutting tool such as a steel bar having a plurality of cutting blades 22a at the tip of a working section 22, includes a main shaft 110, which includes a chuck 112 that holds the steel bar 20 in a freely detachable manner; a main shaft support 120, which holds the main shaft 110 allowing change in a slant angle of the main shaft; an XY table 130, which freely moves the main shaft support 120 in X and Y axis directions; and a rotatable disc whetstone 141, which forms the cutting blades in the working section of the medical cutting tool held by the chuck. The whetstone 141 has a structure within the horizontal plane (XY plane).