Earlier days the prosthetics are not customizable. In operation theatre, the implants are placed over the patients by cutting or modifying the implants during the surgeries. The surgery time is increased during this modification. In this project, first getting the CT/MRI images of the patient in DICOM format and then importing the images into 3D slicer and converted it into 3D model. Then identify the defect parts in the 3Dmodel and segmented the region of interest or defected parts in the 3D image. Designing an implant or prosthetics to fit perfectly over the ROI or defect parts. Then the accuracy of the superimposition is checked, the accuracy is increased to the maximum level. Then patient is being put in supine position and the 3Dmodel is superimposed over the real patient and markings are done. The doctors make the plan with the information gathered from these site markings. At last, the patient is ready for surgery.