A method for creating three-dimensional data of a position of an outer periphery at the occlusal surface side of a keeper includes steps of placing a keeper analog 2 having a reference plane 2a in same shape as and in parallel to a surface Ka at the occlusal surface side of a keeper K to be embedded projectingly on an abutment model 1, three-dimensionally measuring an outside shape of the abutment model 1 having the keeper analog 2, acquiring a normal vector 2aa and an outer periphery 2ab of the reference plane 2a based on the measured three-dimensional data, moving the outer periphery 2ab to a position 3 at the abutment model 1 side by a height 2b of the keeper analog 2 from the reference plane 2a along the normal vector 2aa and acquiring three-dimensional data of the outer periphery Kb based on the position 3.