Abstract: An orthodontic structure includes a body where at least one connecting hole is formed, a fastening part disposed on the body and fastened to an implant, and at least one traction assembly connected to the body. The traction assembly includes an orthodontic table and an adjustment part extending outwards from the orthodontic table to engage the connecting hole. The orthodontic table has at least one locking recess capable of holding a metal wire in place. The orthodontic structure is connected to the implant which is embedded in an alveolar bone in advance to provide a requisite anchorage effect required by orthodontics. Thus, the implant treatment and the orthodontic treatment can be concurrently executed to shorten the treatment time for straightening teeth and attain good implanting and straightening effects.

Abstract: A screw includes a positioning member defined on inclined cutting planes of a drilling portion of the screw for stably allowing a cutting edge constructed at a convergence of the cutting planes to cut efficiently. A threaded section formed on a shank of the screw is extended toward the cutting edge and connected with one end of the cutting edge. The positioning member helps the screw fixedly stand on an object. The cutting edge and the cutting planes allow cutting debris to be swiftly and smoothly extruded therefrom into the threaded section for avoiding the piling of the considerable cutting debris. Thereby, the screwing torque is reduced and the drilling speed is promoted. Preferably, the fastened screw is sunken in the object, and the fastening operation is completed successfully.

Abstract: A screw includes a positioning member defined on inclined cutting planes of a drilling portion of the screw for allowing a cutting edge constructed at a convergence of the cutting planes to cut stably and efficiently. A main threaded section formed on a shank of the screw is extended to connect with one end of the cutting edge. The positioning member helps the screw fixedly stand on an object. The cutting edge and the cutting planes allow cutting debris to be swiftly and smoothly extruded therefrom into the main threaded section for avoiding the accumulation of considerable cutting debris. Thereby, the screwing resistance is reduced and the drilling speed is promoted. Preferably, the fastened screw is firmly sunk in the object, and the fastening operation is completed successfully.

Abstract: A screw includes a positioning member defined on inclined cutting planes of a drilling portion of the screw for stably allowing a cutting edge constructed at a convergence of the cutting planes to cut efficiently. A threaded section formed on a shank of the screw is extended toward the cutting edge and connected with one end of the cutting edge. The positioning member helps the screw fixedly stand on an object. The cutting edge and the cutting planes allow cutting debris to be swiftly and smoothly extruded therefrom into the threaded section for avoiding the piling of the considerable cutting debris. Thereby, the screwing torque is reduced and the drilling speed is promoted. Preferably, the fastened screw is sunken in the object, and the fastening operation is completed successfully.