MECHANICAL AND OSSEOINTEGRATION ANALYSES OF TANTALUM OXYNITRIDE REACTIVE PLASMA SPUTTERED COMMERCIAL PURE TITANIUM IMPLANT IN DIABETIC RABBITS

Background: New studies in the dental field have been focusing on the surface modification and macro design of dental implants to enhance and speed up their primary stability and osseointegration (secondary stability). Attempts are being made to find materials that can enhance and accelerate the formation of bone cells at the implant-bone interface contact area and to improve osseointegration to offer early or immediate loading after implantation and reduce the waiting time, which can be distressing for patients. One of the latest significant findings is that the osseointegration of implants can be improved by changing the surface texture and roughness of the implant. This can increase the rate of success of dental implants, especially in more difficult conditions or areas. In cases of immediate implantation, it is necessary to reduce the period of healing before the loading and to enhance the secondary stability process of dental implants in challenging clinical situations, despite advanced surface modification treatments. Aim: To evaluate the effect of a reactive plasma sputtering tantalum oxynitride (TaON) coating on the osseointegration of commercial pure titanium (CpTi) screws at the implant-bone contact area in diabetic rabbits by measuring the removal torque value (RTV) two weeks post-implantation. Materials and methods: Commercially pure titanium (CpTi) screws were coated with TaON for eight hours using reactive plasma sputtering. Ten (10) white New Zealand rabbits were used, of which five were normal and five were diabetes-induced. The femurs of each rabbit were inserted with two screws, one femur received TaON-coated screws and other one received non-coated, for a total of 40 screws. Twenty (20) screws were inserted in the normal rabbits, 10 of which were non-coated and 10 were TaON-coated. At the same time, the same distribution of 20 screws were inserted in the diabetes-induced rabbits. A reverse torque test (RTT) was performed two weeks post-implantation to measure the implant-bone osseointegration in both groups. Results: The RTV of the TaON-coated CpTi screws from both groups was significantly higher than that of the noncoated CpTi screws two weeks post-implantation. There was an obvious increase in the RTV at the implant-bone interface contact area with time. The RTV of the TaON-coated CpTi screws two weeks post-implantation in the normal rabbits was 34.4 N-cm, 31.2 N-cm in the diabetic rabbits, 27.8 N-cm for the normal rabbits implanted with the non-coated CpTi screws, and 23.7 N-cm for the diabetic rabbits. Conclusion: The coating of CpTi screws with tantalum oxynitride (TaON) by reactive plasma sputtering significantly increased the RTV of the implants and improved osseointegration two weeks post-implantation better than the noncoated CpTi screws in the diabetic and normal rabbits