PROBLEM TO BE SOLVED: To provide a bone screw with which binding force with bone can be properly adjusted.SOLUTION: In the bone screw composed of titanium or titanium alloy, a rough surface part with high surface roughness and a smooth surface part with low surface roughness are formed on a surface of a screw thread, and anodizing is applied to the entire surface area of the screw thread. With the such bone screw, by changing positions of the rough surface part and the smooth surface part on the surface of the screw thread, binding force with the bone can be largely changed, and by appropriately setting forming regions of the rough surface part and the smooth surface part, the binding force with the bone can be properly adjusted. Further, a bone screw having strong binding force with bone can be implemented.COPYRIGHT: (C)2012,JPO&INPIT【課題】骨との結合力を適切に調節し得る骨ねじを提供する。【解決手段】チタン又はチタン合金からなる骨ねじにあって、ねじ山の表面に面粗度の高い粗面部と、面粗度の低い滑面部とを形成するとともに、さらに、ねじ山の表面全域に陽極酸化処理を施すようにした。かかる骨ねじによれば、ねじ山表面の粗面部と滑面部の位置を変化させることによって、骨との結合力を大幅に変化させることができ、粗面部と滑面部の形成部位を適宜設定することで、骨との結合力を適切に調節可能となる。また、骨との結合力の強い骨ねじも実現可能となる。【選択図】図2
