A process for designing and fabricating a custom-fit implant, comprising: a) processing medical image data of a patient's pathologically defective or anatomically deformed area having a symmetrical part to construct a three-dimensional (3D) digital model; b) forming a mirror image of the left or right side of the three-dimensional (3D) digital model based on its axis of symmetry depending on which side the pathologically defective or anatomically deformed area is; c) overlying the mirror image on the original image to form a composite image with a non-overlapping area wherein the implant will be fitted; d) generating a digital implant by cutting off the non-overlapping area of the mirror image; e) designing mounting points between the digital implant and the pathologically defective or anatomically deformed area where the implant is mounted thereon; f) building a positive and a negative mold based on the digital implant to fabricate a custom-fit implant.