Bioengineering Research Group, Nanotechnology and Advanced Materials Department, Materials and Energy Research Center (MERC), Tehran, Iran; Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran; Department of Tissue Engineering & Regenerative Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences (IUMS), Tehran, Iran.
Engineering Ceramics Research Group, Ceramic Department, Materials and Energy Research Center (MERC), Tehran, Iran.
Acta Biomater. 2019 Jun;91:35-47. doi: 10.1016/j.actbio.2019.04.039. Epub 2019 Apr 18.
The title of this article could sound a bit curious to some readers since a layer of apatite - and not calcium carbonate - is well-known to form on the surface of bioactive glasses upon immersion in simulated body fluids. However, calcium carbonate (commonly reported as calcite crystals) can form on the surface of bioactive glasses as well, instead of or in competition with hydroxyapatite, during in vitro tests. Major factors that govern calcium carbonate formation are a high concentration of Ca ions in the testing solution - and, in this regard, glass composition/texture and type of medium play key roles - along with the volume of solution used during in vitro tests. To date, this phenomenon has received relatively little attention and is still partly unexplored. This article provides a critical overview of the available literature on this topic in order to stimulate constructive discussion among biomaterials scientists and further research for better understanding the mechanisms involved in glass bioactivity. STATEMENT OF SIGNIFICANCE: A literature search indicates that a layer of apatite - and not calcium carbonate - is well known to form on the surface of biomaterials during the bioactivity assessment. However, calcium carbonate can form on the surface as well, instead of or in competition with apatite. To date, this phenomenon has received relatively little attention and is still partly unexplored. This review provides a critical overview of the available literature on this topic in order to stimulate constructive discussions that can be further useful for clinical success.
这篇文章的标题可能会让一些读者感到有些好奇，因为众所周知，在模拟体液中浸泡时，生物活性玻璃的表面会形成一层磷灰石，而不是碳酸钙。然而，在体外测试中，碳酸钙（通常报道为方解石晶体）也可以在生物活性玻璃的表面形成，而不是与羟基磷灰石竞争。控制碳酸钙形成的主要因素是测试溶液中高浓度的 Ca 离子——在这方面，玻璃成分/结构和介质类型起着关键作用——以及体外测试中使用的溶液量。迄今为止，这种现象受到的关注相对较少，仍有部分内容尚未得到探索。本文对这一主题的现有文献进行了批判性综述，以激发生物材料科学家之间的建设性讨论，并进一步研究以更好地理解玻璃生物活性涉及的机制。意义声明：文献检索表明，在生物活性评估过程中，生物材料的表面通常会形成一层磷灰石，而不是碳酸钙。然而，碳酸钙也可以在表面形成，而不是与磷灰石竞争。迄今为止，这种现象受到的关注相对较少，仍有部分内容尚未得到探索。本综述对这一主题的现有文献进行了批判性综述，以激发建设性的讨论，这对临床成功可能会进一步有用。
