Integration of Research on Novel Antibacterial Mini-Implant

Biocompatibility has been an indicator for the material selection among early orthodontic mini-screw; therefore, pure-titanium is firstly adopted. Although titanium exhibits a good biocompatibility, the higher cost and lower strength as compared with stainless steel giving rise to the breakage during the orthodontic surgery are two disadvantages. Thus, in recent years, the mini-screw making from austenitic stainless steel with low-cost, high-strength and good biocompatibility has been developed and applied. Due to the oral bacterial infection on the biomedical implant, the morbidity, implant failure and medical expenses are directly influenced. The first step of the infection and inflammation is the bacteria attachment on the medical implants. The bacteria attachment resulting from bacterial aggregation and then the formation of the biofilm leads to the infection and the complexity of the clinical treatment. In addition, bacteria on the surface of the material release the oxide of the hydrogen peroxide, and then this substance corrodes the material surface causing the mini-screw loose, breakage and failure under long-term. Then the time and cost for the treatment is highly enhanced and human health is affected by the releasing ions during the corrosion. Hence, the purpose of this plan dedicates to developing the stainless steel with antibacterial property by adding the metallic element, silver, in AISI 316 stainless steel as an innovative mini-screw. On the other hand, the mini-screws available in the market are mostly imported from Western. Most of them are designed specifically for Westerns, Because of some inherent differences in physical size between Asians and Westerns, the structure of alveolar bone is not exactly the same as well. Therefore, this project will design a mini-screw specific for Asians providing a good fixation during orthodontic treatment. First year: Development and design of the mini-screw: Parameters setting, material designs as well as physical and chemical analyses through XRD, SEM and TEM. Second year: Assessment of the biocompatibility and antibacterial property of the mini-screw Third year: Animal experiment for the mini-screw