即刻加载不同力值的微螺钉支抗种植体骨界面组织学研究

目的：研究微螺钉支抗种植体在不同力值加载条件下与颌骨的结合形式及种植体稳定性。方法：3只杂种犬的下颌骨分别植入24枚钛合金微螺钉种植体,随机分为4组,分别即刻加力0g、200g、400g、600g,8周后处死动物。标本常规脱钙,HE染色和BMP-2免疫组化染色,利用图象分析方法测定骨界面区BMP-2的平均灰度值,分析种植体与骨组织的结合情况。结果：200g、400g组骨界面出现大量成骨细胞及少量类骨质,600g组种植体近颈部周围被大量纤维组织包绕,有炎性细胞浸润,并出现骨组织缺损。种植体骨界面BMP-2的平均灰度值随加载力值的增加而出现先上升后下降的趋势。结论：即刻加载的微螺钉支抗种植体骨界面的结合方式是非完全骨性结合。0～400g矫治力不影响微螺钉种植体的稳定性;而600g矫形力可导致种植体颈部骨组织缺损,其稳定性受到影响。

Histological study of microscrews anchorage implant-bone interface immediately loaded with different or-thodontic force

Objective:To study the stability of the microscrews anchorage implant under the different loads, observe the integration of the bone and implant.Method:Twenty-four titanium alloy mini-screw implants were implanted into the three dogs' mandibular bones. Test implants were randomly divided into four groups with different loads:0 g,200 g,400 g,600 g. After 8 weeks the specimen were fixed,dycalciumed,and then HE and BMP-2 immunohistochemical stained, at last they were assessed with image analysis system to analyze the average grey value. Result:HE staining showed that the osteoblasts and osteoid were presented in the 200 g and 400 g groups.But the 600 g groups was surrounded with fibrous tissue.BMP-2 staining showed that the average gray value increased firstly and decreased lastly.Conclusion:The fibro-osseous integrations was presented at microscrews anchorage implant-bone interface. The group of no force and 400 g force did not influence the stability of microscrews implant. But the group of 600 g force leaded to bone resorption.