The present invention has a technical feature comprising: a through hole forming step (S100) for punching a through hole (11) in a plastic abutment (10)； a ceramic bolt installation step (S200) for inserting a ceramic bolt (B1) into the through hole (11) to fix； a sprue implantation step (S300) for implanting a sprue (20) into the plastic abutment (10)； an investing and lower prosthesis casting step (S400) for separating the plastic abutment (10), wherein the sprue (20) is implanted, from a fixed model (M) and then casting in a mold to make a metallic lower prosthesis (30) wherein an internal screw is formed； a plastic internal screw installation step (S500) for coupling a coupling bolt (B2) to the lower prosthesis (30) to protrude to the outside of the lower prosthesis (30) and installing a plastic internal screw (C) in a protruding portion of the coupling bolt (B2)； a wax model sculpting step (S600) for sculpting a wax model (40) of a shape of an upper prosthesis to cover an outer surface of the lower prosthesis (30)； a wax model separation step (S700) for installing a sprue (20&prime；) in the wax model (40) and separating the wax model (40) from the fixed model (M) and the lower prosthesis (30)； a ceramic bolt installation step (S800) for assembling the ceramic bolt (B1) to the plastic internal screw (C) of the wax model (40)； and an investing and upper prosthesis casting step (S900) for casting the upper prosthesis (50), wherein the internal screw is formed, by infecting melted metal material into the sprue (20&prime；) in a state of investing in a mold.본 발명은 플라스틱 어버트먼트(10)에 관통공(11)을 천공하는 관통공 형성 단계(S100)와； 관통공(11)에 세라믹 볼트(B1)를 삽입하여 고정하는 세라믹 볼트 설치 단계(S200)와； 플라스틱 어버트먼트(10)에 탕구(20)를 식립하는 탕구 식립 단계(S300)와； 탕구(20)가 식립된 플라스틱 어버트먼트(10)를 고정모형(M)에서 분리한 다음 주형에 매몰하여 암나사가 형성된 금속재 하부 보철물(30)을 만드는 매몰 및 하부 보철물 주조 단계(S400)와； 하부 보철물(30)에 결합용 볼트(B2)가 하부 보철물(30)의 외측으로 돌출되도록 체결하고, 돌출된 결합용 볼트(B2) 부분에 플라스틱 암나사(C)를 설치하는 플라스틱 암나사 설치 단계(S500)와； 하부 보철물(30)의 외부면을 감싸도록 상부 보철물 형상의 왁스 모형(40)을
