三种骨移植材料大鼠体内植入的组织学观察

HISTOPATHOLOGICAL CHANGES OF THREE KINDS OF BONE GRAFTS IN VIVO

目的比较3种骨移植材料在大鼠体内降解吸收及诱导周围组织反应的情况,为临床骨缺损修复选择合适的骨移植材料提供理论依据。方法将36只健康成年SD大鼠(体重229～358g)随机分为A、B两组,每组18只,于大腿中部切开长约2cm切口,造成股部肌袋,埋植不同实验材料。A组左侧植入人工骨硫酸钙(calcium sulfate,CS)颗粒(A1组),右侧植入同种异体脱钙骨基质(demineralized bone martrix,DBM)材料(A2组);B组左侧植入异种DBM(B1组),右侧不植入任何材料作为空白对照(B2组)。术后2、4、6周,A、B组各处死6只动物取材,行大体观察和组织学观察,并行组织学评分。结果大体观察:A1组CS颗粒随时间延长逐渐降解吸收;A2组和B1组DBM未见明显吸收,肌肉有纤维化改变,炎性反应均较重;B2组仅见术区组织瘢痕改变。组织学观察:A1组未见明显炎性反应,CS颗粒随时间延长逐步降解吸收,于术后6周完全降解吸收,后期周围组织纤维化表达增加;A2组和B1组炎性反应随时间延长而减轻,DBM降解吸收不明显,可诱导异位肉芽组织并继发纤维化改变,未见明显免疫反应并可观察到异位诱导成骨现象;B2组轻微炎性反应随时间延长而消退,后期有胶原纤维密度增加和血管化发生。A2、B1组与A1、B2组炎性浸润评分比较差异均有统计学意义(P<0.05),A2、B1组间及A1、B2组间差异无统计学意义(P>0.05)。A1、A2、B1组纤维化表达随时间延长而增加,与B2组比较差异均有统计学意义(P<0.05);A1、A2及B1组间差异无统计学意义(P>0.05)。结论CS降解吸收快,生物相容性好,在急性骨折伴缺损和无需承重部位的骨移植中是最佳骨修复填充材料。同种异体和异种DBM具有生物相容性和骨诱导活性,吸收缓慢,适合于下肢承重部位骨缺损和骨不连的修复治疗。

Objective To evaluate the tissue response induced by three kinds of bone transplantation materials implanted in rat so as to provide proper evidence for their clinical application.Methods Thirty-six healthy mature Sprague-Dawly mice, weighing from 229 g to 358 g, were randomly assigned to groups A and B（n=18）.Three kinds of materials were implanted into muscles of rats.Calcium sulfate（CS） granular preparations and allogeneic demineralized bone matrix（DBM） were transplanted into the left（group A1） and right（group A2） thigh muscle pouches of group A.Respectively, whereas xenogenic DBM were transplanted into the left（group B1） thigh muscle pouches of group B and the right（group B2） sites were taken as control without implant.The samples（n=6） were collected to make the observation of gross and histology and to analyze histological score after 2, 4, and 6 weeks.Results The gross observation：implanted materials were gradually absorbed at late stage in group A1.No obvious degradation and absorption, but brosis of tissues were observed in group A2 and B1.The in ammatory reactions were more severe in groups A2 and B1.In group B2, only the changes of scar were seen at operative site.The histological observation：no obvious in ammatory reactions were seen in group A1, CS were gradually absorbed and completely absorbed at 6 weeks, while brosis of tissues increased at late stage.In ammatory reactions in group A2 and group B1 were alleviated gradually, no obvious absorption and degradation were observed.The di erent two DBM could induce granulation tissues and bone formation at di erent sites and secondary brosis with no obvious immune response was observed.In group B2, there was an increase in collagen ber density and angiogenesis at late stage.The scores of in ammatory in ltration were signi cantly higher in groups A2, B1 than in groups A1, B2（P 〈 0.05）, and the scores of brosis was larger in groups A1, A2 and B1 than in group B2（P 〈 0.05）.Conclusion CS has rapid dissolution and good biocompatibility.It is a good replaceable packing materials of bone defects in some upper limb＇s or acute bone fracture.Both of two DBM have biocompatibility and osteoinductive potential, which dissolution are very slow.Due to these capacity, they can be served as an ideal materials in treatment of lower limb＇s bone defect and nonunion.