目的 初步探索可注射磷酸钙骨水泥(calcium phosphate cement,CPC)与聚乳酸-羟基乙酸[poly(lactic-co-glycolic acid),PLGA]微球复合物作为修复材料应用于拔牙位点即刻修复的可行性.方法 用15只犬建立犬下颌即刻拔牙缺损模型,每只犬制备3个下颌骨缺损区,分别植入CPC-PLGA微球复合物(实验组,E组)、颗粒状骨粉(Bio-Oss,阳性对照组,P组)、自体血(空白对照组,B组),4、8、12周后取材观察(每组每个时间点样本量为5),比较各组骨密度、新生骨量.结果 4、8周时各组骨密度差异无统计学意义(P>0.05).12周时E组骨密度(114.9±8.4)与P组(117.4±12.1)差异无统计学意义(P>0.05),但均显著高于B组(95.0±12.6) (P <0.05).术后4周新生骨量P组[(87.5±1.5)%]>B组[(78.7±2.7)%]>E组[(69.2±1.8)%](P<0.05);8、12周新生骨量P组[(94.0±2.3)%和(93.5±1.9)%]与E组[(94.7±1.1)%和(96.0±0.9)%]均显著大于B组[(76.8±3.0)%和(87.0±2.4)%](P<0.05).结论 CPC-PLGA微球复合物即刻修复拔牙位点的效果与颗粒状骨粉相似,可有效保存拔牙位点骨质.
Objective To investigate the feasibility of extraction site preservation using injectable calcium phosphate cement (CPC) combine with poly (lactic-co-glycolic acid) (PLGA) microspheres.Methods Immediate extraction defects models were created in canine mandibles,and the defects were filled with CPC/PLGA (experimental group,E),Bio-Oss (positive control,P),non-treatment (blank control,B) respectively.Dogs were sacrificed after 4,8,12 weeks post operation.Statistical analysis were conducted using SPSS 19.Results Results of radiological observation showed that there were not significantly different between groups in 4 and 8 week(P >0.05).After 12 week,E(114.9 ±8.4)were not significantly different compared with P(117.4 ± 12.1) (P > 0.05),both were significantly higher than B (95.0 ± 12.6)(P <0.05).Histology examination showed that at 4 week following surgery,the result of newly formed bone was as follow,P [(87.5 ± 1.5) %] > B [(78.7 ± 2.7) %] > E [(69.2 ± 1.8) %] (P < 0.05).At8,12 week,results of P[(94.0 ±2.3)% and (93.5 ±1.9)%]and E[(94.7 ±1.1)% and (96.0±0.9)%] were better than those of B[(76.8 ±3.0)% and (87.0 ±2.4)%] (P<0.05).Conclusions The effect of CPC/PLGA repair immediate alveolar ridge defects is the same as that of BioOss,and CPC/PLGA can be used as a material in extraction site preservation.