Sawase Takashi, Jimbo Ryo, Wennerberg Ann, Suketa Naoki, Tanaka Yasuhiro, Atsuta Mitsuru
Division of Applied Prosthodontics, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
Clin Oral Implants Res. 2007 Dec;18(6):680-5. doi: 10.1111/j.1600-0501.2007.01404.x. Epub 2007 Sep 13.
The anatase form of titanium dioxide (TiO2) is one of the most common crystalline forms of TiO2 and is normally produced by oxidation of titanium via thermal oxidation or anodizing. This crystalline form exhibits photocatalytic activity when it is irradiated with ultraviolet A (UVA) light. The aim of the current study was to analyze the crystal structure of anodic-oxidized TiUnite implants and to confirm the photocatalytic properties in vitro and in vivo.
Cross-sectional observations by transmission electron microscopy were used to determine the surface crystal structure on the TiUnite implant. Subsequently, photocatalytic activity was confirmed by degradation of methylene blue, and hydrophilicity was measured based on the water contact angle. Furthermore, the in vivo effects of the photocatalytic activity of this compound were investigated.
An amorphous layer that was about 10 microm thick was observed on the TiUnite implant surface. In the amorphous layer, the anatase form of the crystalline TiO2 was identified. Photocatalytic activity was clearly demonstrated by the bleaching effect of methylene blue under UVA illumination. The contact angle decreased from 44 degrees to 11 degrees after UVA illumination. Although these data suggest increased hydrophilicity for the TiUnite implant, the bone-to-metal contact at 4 weeks was not influenced.
The anodic-oxidized TiUnite implant has inherent photocatalytic activity. UVA illumination increases the surface hydrophilicity of the implant. However, this increase in hydrophilicity does not improve bone apposition to the implant surface at 4 weeks.
二氧化钛（TiO₂）的锐钛矿形式是TiO₂最常见的晶体形式之一，通常通过热氧化或阳极氧化钛来制备。当用紫外线A（UVA）照射时，这种晶体形式表现出光催化活性。本研究的目的是分析阳极氧化TiUnite种植体的晶体结构，并在体外和体内确认其光催化性能。
采用透射电子显微镜进行横截面观察，以确定TiUnite种植体的表面晶体结构。随后，通过亚甲基蓝的降解来确认光催化活性，并基于水接触角测量亲水性。此外，还研究了该化合物光催化活性的体内效应。
在TiUnite种植体表面观察到一层约10微米厚的非晶层。在非晶层中，鉴定出了晶体TiO₂的锐钛矿形式。在UVA照射下，亚甲基蓝的漂白效应清楚地证明了光催化活性。UVA照射后，接触角从44度降至11度。尽管这些数据表明TiUnite种植体的亲水性增加，但4周时骨与金属的接触并未受到影响。
阳极氧化TiUnite种植体具有固有的光催化活性。UVA照射可增加种植体表面的亲水性。然而，这种亲水性的增加在4周时并未改善骨与种植体表面的贴合。
