[关键词]
[摘要]
目的:通过测量正畸微种植体种植在狗下颌骨不同部位的最大植入转矩和拉出力,探讨植入区骨 量、骨密度对正畸微种植体初始稳定性间的影响。方法:选择狗下颌骨为实验模型,制作微种植体植入引导颌 垫;拍螺旋 CT 测量颌垫引导针所对应拟植入区骨质密度。将 24 枚正畸微螺纹种植体以自攻方式垂直骨面植 入,即刻测得微种植体最大植入转矩。通过 CT 片测量微种植体距相邻牙根面固有牙槽骨硬骨板的距离及植入 点至牙槽嵴顶或根分叉处硬骨板的距离。实施微种植体拉出实验,测得拉出力。对微种植体拉出力与植入区骨 质密度、植入区骨量及最大植入转矩的关系进行统计学分析。结果:18 枚微种植体满足实验要求。正畸微种植 体的拉出力161.11±25.66N 与植入区骨密度 CT 值 1281.07±39.85HU、与微种植体距相邻硬骨板距离、与最大植 入转矩95.36±12.40mN.m 均正相关(P<0.05)。结论:选择微种植体与周边骨距离不小于2.0mm 为宜、骨密度高 的颌骨位置点植入正畸微种植体可获得可靠的植入初始稳定性。
[Key word]
[Abstract]
Objective:To investigate the relationship between pull-out force with bone quantity, bone mineral density and insertion torque,by measuring insertion torque and pull-out force of ortho dontic micro-implants which had been implanted in the different parts of the dogs mandible. Methods: Two fresh mandibles of two male health adult dogs in same age and compatriot with complete permanent dentition were used in present study.Occlusal pad with guide pin based on panoramic radiograph films was made.The mandibles were scanned by a CT,to measure bone mineral density of implantation posi tion of dog′s mandible which was guided by guide pin in occlusal pad.Twenty-four orthodontic micro- implants were implanted in the interradicual area in the mandibular buccal side perpendicularly by self -drilling.The maximal insertion torque of every micro-implants was immediately taken by torque mea surementor after implantation.Surrounding bone quantity was measured with CT film.Then,pull out test was performed.Spearman correlation analysis on relationship between bone mineral density and pull-outforce,bone quantity and pull-out force,maximum insertion torque and pull-out force.Results:There were statistically significance positive correlations(P<0.05)between pull out force and bone density, bone quantity and maximal insertion torque.Conclusion:A good initial stability can be got if only the distance between implant to surrounding bone is at least 2 mm and high bone density.
[中图分类号]
R783.5
[基金项目]
收稿日期:2019-04-12;修回日期:2019-07-03 基金项目:中国国家自然科学基金项目(81060090);内蒙古自治区科技厅自然科学基金项目(2018LH03005) 作者简介:包雪梅(1979-),女,内蒙古医科大学附属医院口腔科副主任医师,医学硕士。 通讯作者:陈岩,主任医师,E-mail:1336806259@ qq.com 内蒙古医科大学附属医院口腔科,010050