An abutment connecting a crown that forms an external form of an artificial tooth to a fixture embedded in a gum of a human, and comprising a body, a combination portion formed at an end of the body and combined with the fixture, a threaded portion formed at the body and penetrating through the body, a fixing screw being inserted into the threaded portion to couple the body to a processing device or a jig, a coupling hole formed at the body and penetrating through the body, a coupling unit being inserted into the coupling hole to connect the body and the fixture, and a sectional surface formed at an opposite portion to the combination portion and connected to the processing device or the jig, to position the body in the processing device or in the jig when the body is coupled to the processing device or the jig.