Bronkhorstlaan 10, building 48, 3723 MB Bilthoven, the
Eur Cell Mater. 2019 Jan 28;37:60-73. doi: 10.22203/eCM.v037a05.
Osteoinductive calcium phosphate (CaP) bone grafts have equivalent performance to autografts in repairing critical-size bone defects. The osteoinductive potential of CaP is linked to the size of the surface topographical features. In the present study, two novel biphasic calcium phosphate (BCP) bone grafts were synthesised with either sub-micron- (BCP<µm) or micron-scale (BCPµm) needle-shaped surface topography and compared to dimensionally similar tricalcium phosphate (TCP) with grain-shaped surface structures (TCP<µm and TCPµm). To clarify the possible function of the surface morphology (needle-like vs. grain-like) in initiating bone formation, the four CaP test materials were physicochemically characterised and implanted for 12 weeks in the dorsal muscle of beagles. The sub-micron needle-shaped topography of BCP<µm triggered earlier bone formation (3-6 weeks) as compared to the grain-shaped surface topography of TCP<µm, which formed bone at 6-9 weeks. After 12 weeks, the amount of induced bone formation in both materials was equivalent, based on histomorphometry. The micron-sized needle-shaped surface topography of BCPµm led to limited formation of new bone tissue, whereas its counterpart, TCPµm with grain-shaped surface topography, failed to trigger de novo bone formation. The relative strength of the parameters affecting CaP-driven bone induction was as follows: surface feature size > surface feature morphology > substrate chemistry. BCP materials with needle-shaped sub-micron surface topography gave rise to accelerated bone formation and slower rate of resorption than a comparable TCP. These characteristics may be translated to improve bone healing in orthotopic defects.
具有诱导成骨性能的钙磷（CaP）骨移植物在修复临界尺寸骨缺损方面的性能与自体移植物相当。CaP 的诱导成骨潜能与其表面形貌特征的大小有关。在本研究中，我们合成了两种具有亚微米级（BCP<µm）或微米级（BCPµm）针状表面形貌的新型双相钙磷（BCP）骨移植物，并将其与具有粒状表面结构的类似尺寸的磷酸三钙（TCP）（TCP<µm 和 TCPµm）进行了比较。为了阐明表面形态（针状与粒状）在启动骨形成中的可能作用，我们对四种 CaP 测试材料进行了理化特性表征，并将其植入比格犬背部肌肉中 12 周。与 TCP<µm 的粒状表面形貌相比，BCP<µm 的亚微米针状形貌更早地触发了骨形成（3-6 周），而 TCP<µm 在 6-9 周时才形成骨。12 周后，基于组织形态计量学，两种材料诱导的骨形成量相当。BCPµm 的微米级针状表面形貌导致新骨组织形成有限，而其具有粒状表面形貌的对应物 TCPµm 未能引发新骨形成。影响 CaP 驱动骨诱导的参数的相对强度如下：表面特征尺寸>表面特征形态>基底化学。具有亚微米级针状表面形貌的 BCP 材料引发骨形成的速度更快，吸收速度更慢，与可比的 TCP 相比。这些特性可能被转化为改善原位缺损中的骨愈合。
