Medical implants and implant surgery apparatus and instruments, namely, biodegradable bone fixation implants, medical drill bits for cutting bone, connections in the nature of holders being medical screw connections used for joining and fixing of hydrocephalus shunt catheters, and silicon drainage tubing used for medical purposes; Implantable cranial bone fixation devices for medical use in the nature of surgical clips, metal plates and bone screws implantable in the skull; Medical apparatus for use in surgery and medical implants consisting of artificial material, all of the forgoing being for cranial bone replacement and bone plating; Cranial implants comprising natural, non-living materials; artificial dura maters for human beings, namely, artificial biomaterials for augmentation of tissue for medical purposes