愈合时间对微螺钉种植体-骨结合方式的影响

摘要

目的 通过动物实验研究不同愈合时间微螺钉种植体—骨界面各部位(颈段、中段、尖端)的组织学变化,探讨微螺钉种植体与周围骨组织的结合方式.方法 成年雄性杂种犬3只,每只犬每侧上颌颊侧骨板植入4枚种植钉,共24枚,分别进行即刻负载或愈合4周和8周后加载200 g牵引力,加载8周时处死动物并取材.常规制备标本,采用光镜及扫描电镜观察微螺钉种植体—骨界面的组织学变化.结果 颈部即刻加载时以纤维结合；经过一段愈合期逐渐转向骨性结合.中部及尖端以骨性结合为主.结论 微螺钉种植体—骨界面的变化主要集中在颈部,愈合期是影响界面结合方式的重要因素.%Objective To investigate the histological alterations of the bone-implant interface at different heeling time points,and discuss the healing mode of jaw after insertion of microscrew implant.Methods Four titanium mini-screws were inserted in the each side of maxillary alveolar bone between the dental roots in crossbred dogs (n =3).Healing after 0,4,8 weeks,200 g forces were loaded to the implants.The dogs were sacrificed after 8 weeks.The samples including the microscrew implant and its extracted surrounding bone tissue were fixed,decalcified and sectioned.These sections were then observed under optical microscope and scanning electron microscope from cervical to apex.Results When the force was loaded instantly,there was a uniform intimate bone-implant contact from middle to apex parts,but not in cervical part since the fibrous tissue was present there.Conclusion The bone-implant interface changes mainly occur in the neck,the healing time is an important factor that affects the interfacial bonding.