List the requirements of implant materials.
a) Biologically compatibility: an ideal implant material will elicit mainly physiological reactions within the surrounding tissues (bone, connective tissue and epithelium). The interactions between the implant materials and tissues must not lead to secondary alterations in the organism or to biologic instability of the implant due to corrosion or dissolution and resorption of the implant surface.
b) Mechanical requirements: Dental implants must be able to sustain and transfer loads and should have adequate mechanical strength in order to distribute the forces uniformly.
c) Chemical requirements: It must withstand corrosion by body fluids and not have any direct or indirect negative effects on the surrounding tissue and organism
d) Functionality: it should take maximum advantage of available bone and permit the maximum amount of forces to be transmitted through the implant with in physiologic limits.
e) Should provide desired esthetics and be conducive to oral hygiene maintenance.