A variety of dental devices such as orthodontics, artificial teeth are implanted in oral cavity for long term. The implant coated with protective films, which can reduce corrosion and wear, may prevent the problems described above and extend the lifetime of implants to the benefit of the patients. Diamond-like carbon films have extreme hardness, low friction coefficients, chemical inertness, and high-corrosion resistance. Moreover, these properties make the good candidates as biocompatible coatings for dental devices. In this study, DLC films using the plasma CVD method deposited on acrylic resin and orthodontic archwires have investigated to detect the Ni release from the wires and to estimate cell growth in E-MEM immersed acrylic plates. After 6 months, the concentration of the nickel release from DLC-coated wire and Non-coated wire was 150 [ppb] and 933 [ppb], respectively. Results indicated DLC films inhibit the release of these materials, and prevent degradation of these materials in the solution.