Comparative Study on the Structural Make-Up, Physical and Antibacterial Behavior of Nitride Based and Silicon Doped Coatings—A Brief Review

To improve the life of implant is the ultimate goal of many researches. Coating is one of the methods to improve the surface properties of the implant. The nitride-based coatings have shown better properties in modifying the surface properties. TiN, ZrN and CrN are the few binary nitride-based coating which has shown good physical properties as monolayer, as well as interlayer. To further improve the properties of binary coatings, the metallic or non-metallic elements such as Al, Si, Ti, C, Nb, etc., are added to form ternary and quaternary coatings. AlCrN, TiAlN, and TiSiN are ternary and AlCrSiN and TiAlSiN are quaternary nitride-based coatings. The doping of Si improves the hardness and modulus of the coating. TiN, ZrN, CrN, AlCrN, TiAlN, TiSiN, AlCrSiN, TiAlSiN and hydroxyapatite coatings whose structural, physical and antibacterial properties are discussed. The ion implantation of metals like lead, zinc, silver, copper, iron and other metals improves the antibacterial properties of coatings.