During recent years, there have been efforts in developing Nanocrystalitie Calcium or it to enhance their biological and mechanical properties for use in biomedical applicati Calcium orthophosphate based inorganic bio ceramic materials have a wide range of biomedical applications [1], Bioresorbabie and Bioactive phases of calcium phosphate biocerarnic material$ are choice for bone-tissue engineerinR application because of their similar inorganic composition with the mineral phases of natual boric, excellent biocompatibility and osteoconductivity [2,3]. In 1920 it is reported the first successful medical application of calcium. phosphate in humans [41. Recently most widely-used bioresorbable and bioactive ceramics include calcium orthophosphates (Cal)). They are present in banes, teeth and the tendons of mammals, giving these organs hardness and stability. They are known as non-ion.- substituted calcium orthophosphates with a CalP molar ratio between 0.3 and 2.0_ The most widely used member of the family of CaPs is liydmxyapatire (HA) [5]. Among different forms of calcium phoThate. hydroxyapatite (I-TA) is one of the most promising inorganic biomaterials, HA is the principal mineral constituents of natural bones and teeth [6], Hydroxyapatite CHA) has been widely used as a biomaterial in orthopedics, bicengineerine and dentistry. because of its good biocompatibility [7]_ Synthetic Hydroxyapatite (HA) is the most promising because of good cation exchange rate with metals._ excellent biocompaulbility and high affinity for the pathogenic microorganisms [8-10]_ It is reported that around 70-80% of implants are made of bi000nipatible metals [11]_ With the introduction of a ttansient metal ion such as silver HA can be effective in controlling micloorganisms Due to its ion-exchange capabilities [12]. Synthetic HA with metal doping for Biomedical applications has gained lot of attention because of the high flexibility and stability of apatite sum cturei a great number of cationic substitution are of potential application in the Biomedical Meld, There are many reports of the occupying of Ca sites by various divalent (l1+ig’l.Sr. Cd=’, Raz) and Trivalent cations (A.1]#, Fey-) DA_ However, now days the biggest currant problem in the biomedical field is post-surgical infections arising from recent-implanted synthetic biornaterials, because these provide sites for potential bacterial adhesion [14]. However, there are some limitations of these bioceraruic materials involving the possible release of harmful metal ions through wear and corrosion processes wheu they are exposed to aggressive body environment
