雌激素对骨质疏松时种植体骨愈合的影响:Ⅰ组织学观察

The effect of estrogen replacement therapy on bone healing around titanium implants in osteoporotic rats:I histological observation

目的 :研究雌激素替代治疗对骨质疏松时种植体骨愈合的影响。方法 :选用36只雌性SD大鼠并随机分为假手术组、卵巢切除组及雌激素组。术后12周于每个大鼠胫骨近中干骺端植入纯钛螺纹状种植体 ;雌激素组大鼠从植入术后第一日起肌注苯甲酸雌二醇20μg/kg/3日 ,其他两组注射等量生理盐水。种植术后4周和12周分两批处死大鼠 ,制作带种植体的不脱钙切片 ,行组织学及荧光观察。结果 :在4周及12周两个时间点上 ,假手术组和雌激素组松质骨区种植体周围包绕骨板较厚 ,种植体周围骨小梁密度及与骨组织接触面积均优于卵巢切除组。种植4周时雌激素组荧光染色强度及双标记线宽度均优于卵巢切除组 ,而与假手术组相似 ;种植12周时雌激素组荧光染色表现与卵巢切除组相近。结论 :雌激素替代治疗可促进骨质疏松大鼠松质骨区种植体骨愈合 ;

Objective: To investigate the effect of estrogen replacement therapy on bone healing around titanium implants in ostoeporotic rats.Methods: Thirty six 32-week-old female SD rats were randomly divided into three groups, an ovariectomized group, a sham-operated group and an estrogen-replacement-therapy group. Pure screw titanium implants were placed in the proximal metaphyses of the tibia 12 weeks after ovariectomy surgery and the rats in estrogen group were administrated benzyl estradiol at a dose of 20μg/kg/3days. The rats were killed at 4 and 12 weeks after implant surgery and undecalcified sections with implants were examined histologically to clarify the changes of new bone around titanium implants .Results: At 4 and 12 weeks after implant surgery,the thickness of interface bone lamella , the contact of implants with new bone and the density of trabecular bone around implants in cancellous bone area all increased in estrogen group compared with ovariectomized group, and were similar to those of sham-operated group.The changes of fluorescent observation at 4 weeks after implant surgery were better in sham-operated group and estrogen group than those in ovariectomized group ; while at 12 weeks,there was no obvious difference between estrogen group and ovariectomized group. Conclusion: Estrogen replacement therapy promotes bone healing around titanium implants in osteoporotic rats and it may increase the support of bone to titanium implants.