The present invention provides a dental implant, which is made by forming a blank body through injection molding using zirconium oxide paste in an injection mold and through sintering. Within the injection mold, the interior of the blank body is at least formed with an internal threaded segment and an internal polygonal conic segment. The exterior of the blank is at least formed with a first external threaded segment, a first un-threaded surface, a second external threaded segment, and a second un-threaded surface. The injection mold is configured with a screwing drive and reverse mechanism, an internal thread forming rod, an axial sliding member, an elastic element, a first sliding block and a second sliding block, wherein the parting line for the first sliding block and the second sliding block just passes and forms the first un-threaded surface and the second un-threaded surface of the blank body. During injection, the screwing drive and reverse mechanism is used to drive the internal thread forming rod moving advance in screwing, and push the axial sliding member to an injection positioning point during advancing to form the internal polygonal conic segment of the blank body. After completion of injection, the screwing drive and reverse mechanism reverses the internal thread forming rod in screwing. At this time, the elastic element makes the axial sliding member reversed therewith until both the internal thread forming rod and the axial sliding member may be completely released from the blank body.
