Fast-setting calcium phosphate scaffolds with tailored macropore formation rates for bone regeneration
Fast-setting calcium phosphate scaffolds with tailored macropore formation rates for bone regeneration
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DOI：
10.1002/jbm.a.20093
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发表时间：
2004-03-15
影响因子：
4.9
通讯作者：
Chow, LC
中科院分区：
文献类型：
--
作者：
Xu, HHK;Takagi, S;Chow, LC
磷酸钙骨水泥(CPC)具有良好的骨传导性，可原位自硬形成羟基磷灰石，在颅面及骨科修复中具有很好的应用前景。然而，其强度低、硬化时间长、缺乏大孔率限制了它的使用。本研究旨在研制具有高强度和可剪裁大孔形成率的快凝抗冲刷CPC支架。采用壳聚糖、磷酸钠和羟丙基甲基纤维素(HPMC)对CPC进行快速固化和抗冲刷处理。可吸收纤维和甘露醇致孔剂被加入到CPC中以增强强度和大孔促进骨生长。测量了弯曲强度、折断功和弹性模数随生理溶液浸泡时间的变化。硬化时间(平均+/-SD；n=6)：CPC对照组为69.5±-2.1min，CPC-HPMC-甘露醇为9.3+/-2.8min，CPC-壳聚糖-甘露醇为8.2+/-1.5min，CPC-壳聚糖-甘露醇-纤维为6.7+/-1.6min。后三种成分耐洗脱，而CPC对照糊剂在生理溶液中表现为洗脱。浸泡1d，可溶解甘露醇，并在CPC中形成大孔。CPC-壳聚糖-甘露醇-纤维支架的强度为4.6+/-1.4 Mpa，显著高于CPC-壳聚糖-甘露醇支架的1.2+/-0.1 Mpa和CPC-HPMC-甘露醇支架(Tukey‘s)的0.3+/-0.2 Mpa。CPC-壳聚糖-甘露醇-纤维支架的强度维持到42d后因纤维降解而降低。断裂功和弹性模量表现出相似的趋势。纤维溶解后，CPC中形成了长圆柱状的大孔道。这种可吸收、快速固化、抗冲刷、坚固的CPC支架在颅面及骨科修复中具有良好的应用前景。这种结合快速和缓慢溶解的造孔剂/纤维来制备具有高强度和定制的大孔形成率以匹配骨愈合速度的支架的新方法可能对其他生物材料具有广泛的适用性。(C)2004年威利期刊公司。
Calcium phosphate cement (CPC) is highly promising for craniofacial and orthopedic repair because of its ability to self-harden in situ to form hydroxyapatite with excellent osteoconductivity. However, its low strength, long hardening time, and lack of macroporosity limit its use. This study aimed to develop fast-setting and antiwashout CPC scaffolds with high strength and tailored macropore formation rates. Chitosan, sodium phosphate, and hydroxypropyl methylcellulose (HPMC) were used to render CPC fast-setting and resistant to washout. Absorbable fibers and mannitol porogen were incorporated into CPC for strength and macropores for bone ingrowth. Flexural strength, work-of-fracture, and elastic modulus were measured vs. immersion time in a physiological solution. Hardening time (mean +/- SD; n = 6) was 69.5 +/- 2.1 min for CPC-control, 9.3 +/- 2.8 min for CPC-HPMC-mannitol, 8.2 +/- 1.5 min for CPC-chitosan-mannitol, and 6.7 +/- 1.6 min for CPC-chitosan-mannitol-fiber. The latter three compositions were resistant to washout, whereas the CPC-control paste showed washout in a physiological solution. Immersion for 1 day dissolved mannitol and created macropores in CPC. CPC-chitosan-mannitol-fiber scaffold had a strength of 4.6 +/- 1.4 MPa, significantly higher than 1.2 +/- 0,1 MPa of CPC-chitosan-mannitol scaffold and 0.3 +/- 0.2 MPa of CPC-HPMC-mannitol scaffold (Tukey's). The strength of CPC-chitosan-mannitol-fiber scaffold was maintained up to 42 days and then decreased because of fiber degradation. Work-of-fracture and elastic modulus showed similar trends. Long cylindrical macropore channels were formed in CPC after fiber dissolution. The resorbable, fast-setting, anti-washout and strong CPC scaffold should be useful in craniofacial and orthopedic repairs. The novel method of combining fast- and slow-dissolution porogens/fibers to produce scaffolds with high strength and tailored macropore formation rates to match bone healing rates may have wide applicability to other biomaterials. (C) 2004 Wiley Periodicals, Inc.