雌激素对骨质疏松时种植体骨愈合的影响:Ⅱ骨计量学和电镜观察

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32周龄雌性SD大鼠36只 ,并随机分为假手术组、卵巢切除组及雌激素组。卵巢切除12周后于大鼠胫骨近中干骺端植入纯钛螺纹状种植体 ,雌激素组同时肌注苯甲酸雌二醇。种植术后4周及12周分两批处死大鼠 ,摘取胫骨 ;标本分别进行扫描电镜观察和骨计量学测量。结果 :在种植后4周及12周时 ,雌激素组除12周时皮质骨结合率与卵巢切除组无显著差异外 ,其它各项骨计量学参数均显著高于卵巢切除组 (P<0.05或P<0.01) ;而与假手术组比较 ,除骨矿化速度及4周时单位骨量外 ,其他各项指标均无显著差异 (P>0.05)。电镜观察种植体—骨界面愈合雌激素组和假手术组均优于卵巢切除组。结论 :雌激素替代治疗可促进实验性骨质疏松大鼠种植体骨愈合 ;该方法有助于增加临床绝经性骨质疏松患者牙种植体骨整合率

The effect of estrogen replacement therapy on bone healing around titanium implants in osteoporotic rats: Ⅱ bone histomorphometry and SEM observation

Objective:To investigate the effect of estrogen replacement therapy on bone healing around titanium implants in ovariectomized rats. Method: 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 tibiae 12 weeks after ovariectomy surgery, and the rats in estrogen group were prescribed benzyl estradiol . The tibiae were examined hisotologically by undecalcified sections with bone histomorphometric method and by scanning electron microscope at intervals of 4 and 12 weeks after implant surgery. Results: At 4 and 12 weeks after implant surgery, all the bone histomorphometric paremeters except cortical implant-bone contact rate at 12 weeks, were significantly increased in estrogen group compared with ovariectomized group. While compared with sham-operated group, all above parameters except bone mineralization rate and density of trabecular bone around implants at 4 weeks , which were significantly different, did not show any apparent changes in the estrogen group. Conclusion:Estrogen replacement therapy promotes bone healing around titanium implants in ovariectomized rats, and it may also play a similar role in osseointegration of dental implants in postmenopausal ostoeporotic patients.