Histological study of periodontal tissue treated by implant-anchoraged orthodontic tooth movement

本研究的目的是利用正畸断面弓丝技术确定骨整合钛种植体的支抗电位。选取4只成年beagle犬，分别在其愈合的下颌第二、第三前磨牙的拔除部位，行2枚bronemark 3.75*7 mm钛种植体手术植入。18周后手术揭开种植体，固定第二阶段基台和焊接的边缘管。在种植体和两侧第四前磨牙之间放置带有t形环的分段矩形拱丝（0.017*0.025英寸，不锈钢）。每只狗的单侧段作为实验侧，校准弓丝，使其对第四前磨牙产生120gm的侧向力。对侧节段作为控制侧，不施加正畸力。激活断层线，每两周拍摄下颌印模、口腔照片和口腔（咬合和牙齿）x光片，共4周。下颌弓研究模型显示实验侧第四前磨牙内侧移动2mm，而实验侧种植体、实验侧第四前磨牙和对照侧种植体在实验期间没有移动。牙科x光片显示，种植体对任何狗的任何部分都保持了相当的骨整合。我们的结论是，刚性骨内种植体在正畸水平力方面优于牙锚定，并为成人缺牙患者提供了一种潜在的远端移动方法。

The purpose of this study was to determine the anchorage potential of osseointegrated titanium implants by the use of orthodontic sectional arch wire technique. Two bronemark 3.75*7 mm titanium implants were surgically placed bilaterally in healed mandibular extraction sites of second and third premolars on each side in four adult beagle dogs. The implants were surgically uncovered 18 weeks later and second stage abutments with soldered edgewise tubes secured. Segmental edgwise rectangular arch wires (0.017*0.025 inches, stainless steel) with T-loop were placed between the impants and the fourth premolars in both sides. Unilateral segment of each dog was served as a experimental side and the arch wire was calibrated to produce 120gm lateral force to the fourt premolar. Contralateral segment was served as a control side and orthodontic force was not applied. Sectional wires were activated, mandibular impressions, oral photographs and oral (occlusal and dental) X-rays were taken biweekly for a total period of 4 weeks. Study models of mandibular arches demonstrated taht fourth premolars on experimental sides moved 2mm mesially, however, the implats on experimental side, and fourth premolars and the implants on control side showed no movement during experimental period. Dental X-rays indicated that implants maintained the osseointegrations fairly for either segment of any dogs. We conclude that rigid endosseous implants are superior to dental anchorage for orthodontic horizontal forces and offer a potential means to move misio-distally in adult patients with missing teeth.