In the present invention, a fixture that is implanted in the alveolar bone to form an artificial tooth root, a lower end portion is connected to the fixture, and an upper end portion is a prosthesis (crown or denture). The present invention relates to an abutment to be joined, and a dental implant formed by elastically joining the fixture and the abutment. The fixture is formed with an inclined surface in which the inner diameter of the shaft hole is continuously reduced from a certain position on the inner surface of the shaft hole to the lower part, and along the circumferential direction of the shaft hole at a certain position of the inclined surface. The abutment includes a fastening protrusion that is coupled to the lower fastening shaft portion complementarily to the first fastening portion of the fixture. A first corresponding fastening portion is formed. In the present invention, the abutment rotates in a circumferential direction in a state where the abutment is coupled in the fixture by the complementary coupling of the first fastening portion and the first corresponding fastening portion, and the first correspondence When the fastening portion is detached from the first fastening portion, the fastening protrusion of the first corresponding fastening portion pushes the abutment upward from the fixture by the elastic repulsion action with the inner inclined surface of the shaft hole of the fixture, thereby abutting. A dental implant configured to automatically separate the attachment and the fixture.本発明は、歯槽骨に植立されて人工歯根を形成するフィクスチャー（ｆｉｘｔｕｒｅ）と、下端部は前記フィクスチャーに結合され、上端部は補綴物（クラウン（Ｃｒｏｗｎ）または入れ歯（Ｄｅｎｔｕｒｅ））に結合されるアバットメントと、前記フィクスチャーとアバットメントとを弾性的に結合させてなる歯科用インプラントに関する。前記フィクスチャーは、軸孔の内側面の一定位置から下部に行くほど軸孔の内径が連続的に縮小される傾斜面が形成され、前記傾斜面の一定位置で軸孔の円周方向に沿って少なくとも一つの締結溝のような凹凸部からなる第１締結部が備えられ、前記アバットメントは、下部締結軸部に前記フィクスチャーの第１締結部に相補的に結合される締結突起からなる第１対応締結部が形成される。本発明は、前記第１締結部と第１対応締結部との相補的結合によって前記アバットメントがフィクスチャー内に結合された状態で、前記アバットメントが円周方向に回転して前記第１対応締結部が第１締結部から離脱すると、前記第１対応締結部の締結突起は、前記フィクスチャーの軸孔の内側傾斜面との
