A mechanical rotational-swinging adapter is provided to transfer a continuous rotational input from a driving tool into back-and-forth swinging output via a slotted cam structure. When the rotational-swinging adapter is installed between the nosecone and the air motor of a conventional dental handpiece, the nosecone outputs the back-and-forth swinging movement for dental work such as root canal or prophylaxis treatments.

A mechanical rotational-swinging adapter is provided to transfer a continuous rotational input from a driving tool into back-and-forth swinging output via a slotted cam structure. When the rotational-swinging adapter is installed between the nosecone and the air motor of a conventional dental handpiece, the nosecone outputs the back-and-forth swinging movement for dental work such as root canal or prophylaxis treatments.

Provided is a roller bearing in which a restraining force of a seal member is further strengthened. The roller bearing includes: an outer ring having an outer ring raceway surface on an inner peripheral surface; an inner ring having an inner ring raceway surface on an outer peripheral surface; a plurality of rolling elements rotatably arranged between the outer ring raceway surface and the inner ring raceway surface; and a seal member that is fixed to a seal attachment groove formed in an axially end portion of the outer ring by a snap ring and seals an axially end portion of a bearing internal space between the outer ring and the inner ring, in which an outer diameter of the seal member is larger than an outer diameter of the snap ring in the seal attachment groove, and in which a radially outer end portion of the seal member is sandwiched between an inner peripheral surface of the seal attachment groove and an outer peripheral surface of the snap ring.

Provided is a roller bearing in which a restraining force of a seal member is further strengthened. The roller bearing includes: an outer ring having an outer ring raceway surface on an inner peripheral surface; an inner ring having an inner ring raceway surface on an outer peripheral surface; a plurality of rolling elements rotatably arranged between the outer ring raceway surface and the inner ring raceway surface; and a seal member that is fixed to a seal attachment groove formed in an axially end portion of the outer ring by a snap ring and seals an axially end portion of a bearing internal space between the outer ring and the inner ring, in which an outer diameter of the seal member is larger than an outer diameter of the snap ring in the seal attachment groove, and in which a radially outer end portion of the seal member is sandwiched between an inner peripheral surface of the seal attachment groove and an outer peripheral surface of the snap ring.

Provided is a detection tool that detects a temperature of air. The detection tool includes a detection section that detects a temperature of air released from an air turbine handpiece, and a main body that includes a surface. The detection section is provided on the surface to allow the air turbine handpiece to be brought close to the detection section

The invention relates to a rotor (1) having a turbine wheel (3) driven by propellant (TG) in a turbine housing (2), a dental preparation instrument (20) having such a rotor (1) and a method (100) for operating such a preparation instrument (20), wherein at least one part of the propellant (TG) flows back to the gas outlet opening (51) in an inner wall (21) radially orbiting the turbine wheel (3) through a return flow channel (6) after impinging on at least one of the drive blades (31) of the turbine wheel (3) counter to the direction of rotation (DR) of the turbine wheel (3), the inner wall (21) in the segment of a circle (KS) comprises at least one return flow channel (6) extending at least from the gas inlet opening (41) as far as the gas outlet opening (51), which allows at least one part of the propellant (TG) to flow back to the gas outlet opening (51) through the return flow channel (6) after impinging on at least one of the drive blades (31) counter to the direction of rotation (DR) of the turbine wheel (3), wherein, in axial direction (AR), the turbine housing (2) has at least one cross-sectional extension (8) of a surface between drive blades (31) and inner wall (21) as far as the return flow channel (6).

The invention relates to a rotor (1) having a turbine wheel (3) driven by propellant (TG) in a turbine housing (2), a dental preparation instrument (20) having such a rotor (1) and a method (100) for operating such a preparation instrument (20), wherein at least one part of the propellant (TG) flows back to the gas outlet opening (51) in an inner wall (21) radially orbiting the turbine wheel (3) through a return flow channel (6) after impinging on at least one of the drive blades (31) of the turbine wheel (3) counter to the direction of rotation (DR) of the turbine wheel (3), the inner wall (21) in the segment of a circle (KS) comprises at least one return flow channel (6) extending at least from the gas inlet opening (41) as far as the gas outlet opening (51), which allows at least one part of the propellant (TG) to flow back to the gas outlet opening (51) through the return flow channel (6) after impinging on at least one of the drive blades (31) counter to the direction of rotation (DR) of the turbine wheel (3), wherein, in axial direction (AR), the turbine housing (2) has at least one cross-sectional extension (8) of a surface between drive blades (31) and inner wall (21) as far as the return flow channel (6).

Disclosed herein is a mountable dental device for shaping a tooth of a subject. The device includes: (i) an anchoring member configured to be removably affixed to a jaw of a subject by securing thereof to one or more teeth of the subject, and (ii) a computerized numerical control (CNC) machine fixedly mounted or mountable on the anchoring member. The CNC machine is configured to have installed thereon and maneuver a dental turbine. When the anchoring member is affixed to the jaw, the device is supported by the subject. The anchoring member is adjustable such as to allow the affixing thereof to jaws of different subjects. The CNC machine is configured to control operation of the dental turbine in at least one dental tooth-shaping procedure on at least one tooth of the subject.

Disclosed herein is a mountable dental device for shaping a tooth of a subject. The device includes: (i) an anchoring member configured to be removably affixed to a jaw of a subject by securing thereof to one or more teeth of the subject, and (ii) a computerized numerical control (CNC) machine fixedly mounted or mountable on the anchoring member. The CNC machine is configured to have installed thereon and maneuver a dental turbine. When the anchoring member is affixed to the jaw, the device is supported by the subject. The anchoring member is adjustable such as to allow the affixing thereof to jaws of different subjects. The CNC machine is configured to control operation of the dental turbine in at least one dental tooth-shaping procedure on at least one tooth of the subject.

A dental handpiece and method of turbine support therein, comprises a turbine wheel having a rotor shaft rotatably supported by a housing via ball bearings, and configured to rotationally drive a clamping chuck, at least one of the ball bearings including, an inner ring arranged on the rotor shaft, the inner ring having a raceway, an outer ring, having an outer raceway movably supported by the housing, and balls arranged between and guided by the inner and outer raceways. The raceway of the inner ring, in cross section, has a concave shape with a curvature corresponding to a radius of the balls. Optionally, the raceway of the outer ring in cross section, has, in a central area, a first curvature with a first radius and, adjoining the central area, a second curvature with a second radius, the first radius being smaller than the second. Optionally, the raceway of the outer ring has a substantially parabolic profile.