Haman J D, Lucas L C, Crawmer D
Department of Biomedical Engineering, University of Alabama, Birmingham 35294, USA.
Biomaterials. 1995 Feb;16(3):229-37. doi: 10.1016/0142-9612(95)92122-m.
Bioceramic coatings, created by the high velocity oxy-fuel combustion spraying of hydroxyapatite (HA) powders onto commercially pure titanium, were characterized in order to determine whether this relatively new coating process can be successfully applied to bioceramic coatings of orthopaedic and dental implants. Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy were used to characterize both the HA starting powders and coatings. A 12 wk immersion test was conducted and the resulting changes in the coatings were also characterized. Calcium ion release during dissolution was measured with flame atomic absorption during the first 6 weeks of the immersion study. A comparison of powder and coating X-ray diffraction patterns and lattice parameters revealed an HA-type coating with some loss in crystallinity. Fourier transform infrared results showed a partial loss of the OH- group during spraying, however the phosphate groups were still present. Scanning electron microscopy analysis showed a lamellar structure with very close coating-to-substrate apposition. The coatings experienced a loss of calcium during the immersion study, with the greatest release in calcium occurring during the first 6 days of the study. No significant structural or chemical changes were observed during the 12 wk immersion study. These results indicate that the high velocity oxy-fuel process can produce an HA-type coating; however, the process needs further optimization, specifically in the areas of coating-to-substrate bond strength and minimization of phases present other than HA, before it would be recommended for commercial use.
通过高速氧燃料燃烧喷涂羟基磷灰石（HA）粉末到工业纯钛上制备生物陶瓷涂层，并对其进行表征，以确定这种相对较新的涂层工艺是否能够成功应用于骨科和牙科植入物的生物陶瓷涂层。使用傅里叶变换红外光谱、X射线衍射和扫描电子显微镜对HA起始粉末和涂层进行表征。进行了为期12周的浸泡试验，并对涂层产生的变化进行了表征。在浸泡研究的前6周内，用火焰原子吸收法测量溶解过程中的钙离子释放。粉末和涂层X射线衍射图谱及晶格参数的比较显示，涂层为HA型，但结晶度有所损失。傅里叶变换红外光谱结果表明，喷涂过程中OH基团部分损失，但磷酸基团仍然存在。扫描电子显微镜分析显示涂层具有层状结构，涂层与基体贴合紧密。在浸泡研究过程中，涂层中的钙有所损失，在研究的前6天钙释放量最大。在为期12周的浸泡研究中未观察到明显的结构或化学变化。这些结果表明，高速氧燃料工艺能够制备出HA型涂层；然而，在推荐用于商业用途之前，该工艺需要进一步优化，特别是在涂层与基体的结合强度以及使除HA以外的其他相最少化方面。
