Abstract
Dental archwires and miniscrews are frequently used in the orthodontic treatments which are very popular nowadays owing to various healthy and cosmetic reasons. Commercial titanium and titanium-based archwires and miniscrews are anodized and examined in this study. The β-Ti archwires with different colors are produced by anodization with different anodized voltages. The surface of anodized wire is titanium oxide, and the oxidation states of Ti vary from TiO2 on the surface to inwardly a mixture of TiO2 and Ti2O3. For most of the anodization conditions, the oxide layers are amorphous. The thickness of oxide layer is determined by TEM and AES. The color of the anodized β-Ti archwires are primarily controlled by the thickness of the oxides which increases with the magnitudes of the applied voltage. With longer anodization time, the archwires change to milky white color. Composition and structure analysis results of the milky white archwires indicate that it is still TiO2 on the surface, but the titanium oxide layers became crystalline. Ti-6Al-4V miniscrews with mesoporous surfaces are produced by anodization using electrolyte with a small amount of fluorine. The mesoporous surfaces could significantly affect the products' osseointegration properties which need to be further explored. In the study of friction experiments, the anodized β-Ti and Ni-Ti archwires shows lower friction than the β-Ti archwires in the conventional stainless steel bracket with elastomeric ligature. When the friction experiments are carried out using the Damon3MX self-ligating bracket rather than the conventional bracket, the friction is singnificantly lower for all the archwires with and witout anodization and no differences can be observed between various archwires.