Experimental study about the effect of the calcium phosphate paste to the central nervous system in the cranio-maxillo-facial area

一些文献表明，磷酸钙糊剂(CPP)可以在手术中成型，具有良好的生物相容性和骨传导性。在颅颌面外科和骨科的临床应用中，CPP均取得了满意的效果。然而，CPP有流入颅腔的风险，而且CPP对中枢神经系统的安全性尚未被证明。在本研究中，我们将CPP植入日本大白兔的骨缺损处，以研究CPP对颅颌面部中枢神经系统的影响。第1组(n=5)，去除颅骨和硬膜外后，在脑表面植入CPP。第2组(n=5)，用手术刀切断硬膜外，用线缝合后，将CPP植入硬膜外。第3组(n=5)硬膜外植入CPP。第4组(n=5)骨缺损处未行CPP。通过脑脊液检测和血液检测评价CPP对中枢神经系统的影响。在所有标本中，CPP植入后均出现暂时的非细菌性脑膜反应。然而，任何一只兔子都没有表现出转化或瘫痪。第1组非细菌性脑膜反应持续时间稍长于其他组，植入后56d恢复至术前水平。我们估计这是由于手术处理的程度，CPP没有给中枢神经系统带来任何不可逆的反应。结论：CPP在颅颌面部有一定的实用价值。

Calcium phosphate paste(CPP) has been showed to be able to be molded during operation with good biocompatibility and osteoconductivity in some literatures. In clinical cases of the cranio-maxillo-facial surgery and the orthopedic surgery, CPP was used to bring satisfactory results. However CPP has a risk of flowing into the intra-cranial cavity and the safety of CPP to the central nervous system has not been showed yet. In this study, we implanted CPP into bone defects in Japanese White rabbits to study the effect of the CPP to the central nervous system in the cranio-maxillo-facial area. In group 1(n=5) , CPP was implanted on the surface of brain after the cranial bone and epidural were removed. In group 2(n=5) , CPP was implanted on epidural after the epidural was cut with the surgical knife and repaired with thread. In group 3(n=5) , CPP was implanted on epidural. In group 4(n=5) , no CPP was received in bone defects. The effect of the CPP to the central nervous system was evaluated by cerebrospinal fluid test and blood test. In all of the specimens, temporarily non-bacterial meningeal reactions revealed after the implantation of CPP. However any rabbit did not reveal conversion or paralysis. In group 1, non-bacterial meningeal reactions continued a little longer than in other groups and restored to the pre-operative standard by 56 days after the implantation. We have estimated that this was due to the degree of surgical handling and CPP did not bring any unreversible reactions to the central nervous system. We conclude that CPP has possibility of being utility in the cranio-maxillo-facial area.