An implant system comprising at least two fixtures, wherein the at least two fixtures comprise: a first fixture comprising a first body and a first thread part, the first thread part having a spiral shape and disposed on at least a part of an outer surface of the first body; and a second fixture comprising a second body and a second thread part, the second body having the same shape and size as those of the first body, the second thread part having a spiral shape and disposed on at least a part of an outer surface of the second body, wherein a diameter of the second thread part is different from a diameter of the first thread part, wherein each of the first and second fixtures further comprises an entrance guide part extending upward from a bottom side of the body to a predetermined position of the body, so as to guide the body when the body is implanted, wherein the entrance guide part comprises: a flat portion disposed at the bottom side of the body; an inclined portion extending upward from an edge of the flat portion and having an upwardly increasing radius; and a rounded portion connected between the inclined portion and the thread part and rounded toward a vertical of the body, wherein each of the first and second fixtures comprises: a taper part having a downwardly decreasing diameter; and a cylinder part extending from a bottom side of the taper part and having a uniform diameter, wherein each of the bodies of the first and second fixtures comprises a bevel part at an upper side, at least one cutting edge portion disposed in the thread part and extending downward along a circumferential direction of the body; an abutment coupling part recessed from a topside of the body to a predetermined depth; wherein said at least one cutting edge portion comprises even number cutting edge portions, and each of the two even number cutting edge portions are disposed at opposite positions. a first fixture comprising a first body and a first thread part, the first thread part having a spiral shape and disposed on at least a part of an outer surface of the first body; and a second fixture comprising a second body and a second thread part, the second body having the same shape and size as those of the first body, the second thread part having a spiral shape and disposed on at least a part of an outer surface of the second body, wherein a diameter of the second thread part is different from a diameter of the first thread part, wherein each of the first and second fixtures further comprises an entrance guide part extending upward from a bottom side of the body to a predetermined position of the body, so as to guide the body when the body is implanted, wherein the entrance guide part comprises: a flat portion disposed at the bottom side of the body; an inclined portion extending upward from an edge of the flat portion and having an upwardly increasing radius; and a rounded portion connected between the inclined portion and the thread part and rounded toward a vertical of the body, wherein each of the first and second fixtures comprises: a taper part having a downwardly decreasing diameter; and a cylinder part extending from a bottom side of the taper part and having a uniform diameter, wherein each of the bodies of the first and second fixtures comprises a bevel part at an upper side, at least one cutting edge portion disposed in the thread part and extending downward along a circumferential direction of the body; an abutment coupling part recessed from a topside of the body to a predetermined depth; wherein said at least one cutting edge portion comprises even number cutting edge portions, and each of the two even number cutting edge portions are disposed at opposite positions. a flat portion disposed at the bottom side of the body; an inclined portion extending upward from an edge of the flat portion and having an upwardly increasing radius; and a rounded portion connected between the inclined portion and the thread part and rounded toward a vertical of the body, wherein each of the first and second fixtures comprises: a taper part having a downwardly decreasing diameter; and a cylinder part extending from a bottom side of the taper part and having a uniform diameter, wherein each of the bodies of the first and second fixtures comprises a bevel part at an upper side, at least one cutting edge portion disposed in the thread part and extending downward along a circumferential direction of the body; an abutment coupling part recessed from a topside of the body to a predetermined depth; wherein said at least one cutting edge portion comprises even number cutting edge portions, and each of the two even number cutting edge portions are disposed at opposite positions. a taper part having a downwardly decreasing diameter; and a cylinder part extending from a bottom side of the taper part and having a uniform diameter, wherein each of the bodies of the first and second fixtures comprises a bevel part at an upper side, at least one cutting edge portion disposed in the thread part and extending downward along a circumferential direction of the body; an abutment coupling part recessed from a topside of the body to a predetermined depth; wherein said at least one cutting edge portion comprises even number cutting edge portions, and each of the two even number cutting edge portions are disposed at opposite positions.