Department of Dental Materials Science and Technology, Faculty of Dentistry, Universitas Padjadjaran, Sumedang-Jatinangor, Indonesia; Oral Biomaterials Study Center, Faculty of Dentistry, Universitas Padjadjaran, Bandung, Indonesia.
Department of Biomaterials, Faculty of Dental Science, Kyushu University, Fukuoka, Japan; Department of Dental Engineering, Bioengineering Section, Faculty of Dental Science, Fukuoka Dental College, Fukuoka, Japan.
J Mech Behav Biomed Mater. 2018 Dec;88:463-469. doi: 10.1016/j.jmbbm.2018.08.021. Epub 2018 Aug 23.
The aim of this present study was to investigate the effect of setting atmosphere on replacement of apatite cement with new bone both in vitro and in vivo.
Apatite cement consisting of an equimolar mixture of tetracalcium phosphate and anhydrous dicalcium phosphate was mixed with distilled water and allowed to set at 37 °C and 100% relative humidity under 0% 5%, and 100% CO atmospheres. X-Ray diffraction and Fourier Transform Infrared Spectroscopy were employed to confirm the carbonate apatite formation. Micro-CT and histological evaluation was made at 1 and 6 month(s) using twelve 10-week-old specific-pathogen-free male Wistar rats.
B-type carbonate apatite was found when the apatite cement was set under 100% CO and 5% CO. More carbonate apatite was formed in the case of 100% CO when compared with 5% CO, and none was formed under 0% CO. Interestingly, unreacted tetracalcium phosphate was significant when apatite cement was set under 0% CO, indicating the formation of Ca-deficient hydroxyapatite. When a bone defect of rat tibia was reconstructed in these conditions of apatite cement and sintered hydroxyapatite, replacement of the apatite cement was confirmed 6 months after implantation, whereas no replacement was observed in the case of sintered hydroxyapatite. The amount of replacement of apatite cement with bone was greater, on the order of 100% CO and 5% CO, followed by 0% CO.
The results obtained in the present study demonstrated that setting atmosphere clearly plays an important role in the replacement of set apatite cement with bone.
本研究旨在探究体外和体内环境下，不同气氛设定对磷酸钙水泥（由等摩尔的磷酸四钙和无水磷酸二钙组成）被新骨替代的影响。
磷酸钙水泥与蒸馏水混合，在 37°C 和 100%相对湿度下，分别在 0%、5%和 100%CO 气氛中凝固。采用 X 射线衍射和傅里叶变换红外光谱分析来确认碳酸磷灰石的形成。在 1 个月和 6 个月时，使用 12 只 10 周龄无特定病原体雄性 Wistar 大鼠进行微 CT 和组织学评估。
在 100% CO 和 5% CO 气氛中凝固时，发现了 B 型碳酸磷灰石。与 5% CO 相比，100% CO 气氛中形成的碳酸磷灰石更多，而在 0% CO 气氛中则没有形成。有趣的是，在 0% CO 气氛中凝固时，未反应的磷酸四钙含量显著，表明形成了缺钙羟基磷灰石。当在这些磷酸钙水泥和烧结羟基磷灰石的条件下重建大鼠胫骨骨缺损时，植入 6 个月后确认了磷酸钙水泥的替代，而在烧结羟基磷灰石的情况下则没有观察到替代。与 0% CO 相比，在 100% CO 和 5% CO 条件下，磷酸钙水泥被骨替代的量更大。
本研究结果表明，气氛设定对凝固的磷酸钙水泥被骨替代的过程起着重要作用。
