An embodiment of this invention is a fixture for dental implant containing a small groove. The small groove has a first wall provided on a front end side and a second wall provided on a back end side. The first wall is extended so as to leave away from a first reference plane while departing from a first base, and the second wall is extended so as to parallel to the first reference plane, or leave away from a first reference plane while depart from a first base. An angle α formed by the first wall and the first reference plane is larger than an angle β formed by the second wall and the first reference plane. The present invention also provides a dental implant containing the fixture for dental implant.本發明之實施形態的牙科植牙用牙根係具備小溝部,前述小溝部係具有:位於前端部側之第1側壁部、以及位於後端部側之第2側壁部。前述第1側壁部係以隨著從第1底部離開而遠離第1基準面之方式延伸,前述第2側壁部係以平行於前述第1基準面、或隨著從前述第1底部離開而遠離前述第1基準面之方式延伸,前述第1側壁部與前述第1基準面構成之角的角度α大於前述第2側壁部與前述第1基準面構成之角之角度β。本發明亦提供一種具備該牙科植牙用牙根之牙科植牙。1A‧‧‧牙根2‧‧‧本體部3‧‧‧大溝部4‧‧‧小溝部4A‧‧‧第1小溝部4B‧‧‧第2小溝部21‧‧‧前端部22‧‧‧後端部23‧‧‧外周部231‧‧‧前方部232‧‧‧後方部S1‧‧‧中心軸
