Study On Surface Modification Of Titanium Used For Dental Implant

The application of dental implant restoration technique has been more and more common in the field of stomatology and titanium is the most commonly used material for implant system. However, the pure titanium implant system has a higher risk of abutment screw loosening because of its own low hardness, fatigue strength and wear-resisting performance. Meanwhile, as a kind of inert metal material, pure titanium is short of initiative in the osseointegration process. These defects greatly reduce the reliability and service life of the implant system. This thesis consists of two parts:Depostion of diamond-like carbon film on medical titanium and plasma oxidation on SLA titanium. The research mainly aims at improving the mechanical properties and biological activity of the titanium used on dental implant through these two surface modification methods.In this paper, the DLC films were diposited on surface of medical titanium. The composition of DLC films obtained by different process conditions was analyzed by Raman test. The highest content of sp3 bondings was found in the film obtained with the optimum technology parameters as followed:Ar/CH4=10sccm/10sccm,300W RF power and -200V DC bias voltage. The content of sp3 bondings is 36.28% calculated by XPS test. SEM observation demonstrated that the DLC film is smooth, homogeneous and compact. DLC film showed high hardness and good biological lubricity in nano-hardness test and friction/wear test in saline environment. Therefore, it can be used as bearing and wear-resisting coating on surface of titanium implant.The SLA titanium was plasma oxidated by using RF-PECVD technology and the process parameters were optimized by evaluating the surface contact angle. Super-hydrophilic surface, on which the contact angle would approach 0°, can be achieved with the optimum technology parameters as followed:Ar/O2=10sccm/10sccm,250W RF power,-500V DC bias voltage and 1 hour oxidation time. XPS and XRD test indicated that the surface chemical composition of the sample is polycrystal composed of TiO, Ti2O3 and TiO2, including anatase and rutile growing along (1,0,1) cystal plane. SEM observation showed that the plasma oxidation in-situ formed a layer of titanium oxide on the original surface, but didn't change the porous morphology obtained by SLA treatment. Adhesion and proliferation experiments of osteogenic cells proved that plasma oxidation treatment can make the SLA titanium sample with better biological activity.