微型种植体支抗压低犬切牙移动过程中牙周牙根骨性组织的变化

背景:牙齿压低移动更容易造成牙根吸收,以往针对矫正引起牙根吸收的研究或基于X射线片的回顾性临床研究,或因无法精确控制压低力量,结果误差较大。目的:建立应用微型种植体支抗压低犬切牙的实验动物模型,观察牙齿压低移动过程中牙周、牙根骨组织学的变化,以评价该治疗方法的可行性及安全性。方法:将9只犬分为5组:对照组1只,未加力;1周、2周、4周、12周组每组2只,在上颌两侧第二、三切牙牙根之间唇侧的牙槽间隔处植入微型种植体作为支抗,每侧施加100g的牵引力压低上颌两侧第一、二切牙,分别于加力后1,2,4,12周(主动加力4周,撤力后保持8周)时处死动物,将第一、二切牙连同牙龈、牙槽骨完整切取,制作组织学标本,苏木精-伊红染色,观察牙周、牙根的组织学变化。结果与结论:与对照组相比,1周组组织改建主要在根尖部和牙槽嵴顶,牙槽骨及牙骨质可见吸收,牙周膜局部出现玻璃样变性;2周组骨质吸收程度及范围明显扩大,吸收有从根尖部向根中及颈部扩展的现象;4周组骨质吸收仍然活跃,牙周膜玻璃样变性消失;12周组牙槽骨及牙骨质表面显著修复,骨陷窝新骨沉积,牙周膜排列有序。提示应用微型种植体支抗压低牙齿,早期组织变化主要在根尖部和牙槽嵴顶,表现...

Histological changes of tooth root and periodontal tissue during mini-implant anchorage for incisor intrusion in dogs

BACKGROUND:Tooth intrusion easily leads to root resorption.Previous studies regarding orthodontic treatment-caused tooth root resorption or retrospective clinical studies based on X-ray films have great errors in outcome evaluation because of intrusion force which cannot be precisely controlled.OBJECTIVE:This study established dog models ofmini-implant anchorage for incisor intrusion to observe the histological changes of tooth root and periodontal tissue and to evaluate the feasibility and safety ofmini-im...