Endodontic instruments are described which have at least a section with a center of mass offset from an axis of rotation so that when the instrument is rotated, the section bends away from the axis of rotation.

A curved handpiece for dental root canal treatment forms an overall scheme of a dental curved handpiece, which is internally conductive, surface insulated, compact in structure, small in height and size and convenient to repair. A dental root canal length measuring function can be realized accurately, safely and stably, and a stable two-in-one function of combining root canal preparation and dental root canal length measurement is further realized. The structure is compact as a whole, and a good visual field is provided. The risk of instrument separation or preparation step generation in the operation process of doctors is reduced, and the safety improvement is greatly guaranteed. According to the scheme, it is convenient to disassemble, repair and clean, the risk of cross infection is reduced, and the use safety and convenience effects of the present invention are further improved. The curved handpiece has great market benefits.

A curved handpiece for dental root canal treatment forms an overall scheme of a dental curved handpiece, which is internally conductive, surface insulated, compact in structure, small in height and size and convenient to repair. A dental root canal length measuring function can be realized accurately, safely and stably, and a stable two-in-one function of combining root canal preparation and dental root canal length measurement is further realized. The structure is compact as a whole, and a good visual field is provided. The risk of instrument separation or preparation step generation in the operation process of doctors is reduced, and the safety improvement is greatly guaranteed. According to the scheme, it is convenient to disassemble, repair and clean, the risk of cross infection is reduced, and the use safety and convenience effects of the present invention are further improved. The curved handpiece has great market benefits.

The invention aims to provide a rotation tool enabling work without obstructing a view of an operator and facilitating fine-adjustment for the tool. A rotation tool includes a flexible shaft including a tool portion at one end and a grip portion at the other end; and a cylindrical exterior body including curved portion on at least a part thereof, wherein a spiral protrusion is formed on at least a part of the shaft and a spiral groove is formed on at least a part of the curved portion, and the shaft is configured to be movable inside the exterior body by screwing the spiral protrusion and the spiral groove to each other.

An endodontic instrument that includes a tapered rod, the rod including an active portion and a distal end, the active portion defining an envelope having a longitudinal axis that coincides with an axis of rotation of the instrument.

An endodontic instrument that includes a tapered rod, the rod including an active portion and a distal end, the active portion defining an envelope having a longitudinal axis that coincides with an axis of rotation of the instrument.

A handle system for supporting a tool defining a tool axis during the performance of dental procedures comprises a handle defining a handle axis, a rotation sleeve, a head assembly and a gear set comprising first and second gear portions. The rotation sleeve supports the first gear portion. The head assembly supports the second gear portion. The handle supports the rotation sleeve for rotation relative to the handle. The handle supports the head assembly such that the first gear portion engages the second gear portion. With the head assembly supported by the handle, the head assembly engages the tool to support the tool such that the tool axis extends at a first angle relative to the handle axis and rotation of the rotation sleeve relative to the handle causes axial rotation of the tool about the tool axis.

An endodontic file holder includes a wearing member worn on a part of the body; a holder body mounted on the outer side of the wearing member, having an inner side in which an accommodating space for accommodating a sponge is formed, and having openings through which the sponge accommodated in the accommodating space is exposed; a sponge inserted inside of the accommodating space formed in the holder body, wherein an endodontic file is inserted into the sponge; and a length measuring means provided in the holder body and configured to measure the length of an endodontic file, wherein at least one medicine receiving groove for accommodating a medicine for dental treatment to be applied to an endodontic file is formed on the upper surface of the holder body.

An endodontic file holder includes a wearing member worn on a part of the body; a holder body mounted on the outer side of the wearing member, having an inner side in which an accommodating space for accommodating a sponge is formed, and having openings through which the sponge accommodated in the accommodating space is exposed; a sponge inserted inside of the accommodating space formed in the holder body, wherein an endodontic file is inserted into the sponge; and a length measuring means provided in the holder body and configured to measure the length of an endodontic file, wherein at least one medicine receiving groove for accommodating a medicine for dental treatment to be applied to an endodontic file is formed on the upper surface of the holder body.

An endodontic file for dental nerve treatment according to the present invention comprises: a helical shaped blade that is to be inserted into a root canal, remove dental nerve, and enlarge the root canal; a head that is detachably inserted into a rotary power tool, and a connection part extending by a predetermined length between the head and the blade and having a diameter smaller than that of each of a contact end of the blade and the head. According to the endodontic file for dental nerve treatment, by forming the connection part of the endodontic file with an adjusted thickness or shape such as a thin thickness so that stress generated during rotation of the endodontic file is concentrated on the connection part rather than the blade, the endodontic file is induced to be fractured outside the tooth rather than inside the tooth root, thereby allowing fractured pieces to be easily found and removed.