Journal of Prevention and Treatment for Stomatological Diseases ›› 2020, Vol. 28 ›› Issue (11): 705-709.DOI: 10.12016/j.issn.2096-1456.2020.11.004

• Basic Study • Previous Articles     Next Articles

Changes in canine position during maxillary molar distalization with mini-implant and CD appliance: an in vitro study

CHEN Jianming(),TAN Yuanhuan,HU Yaozheng,PENG Jing   

  1. Key Laboratory of Oral Medicine, Guangzhou Institute of Oral Disease, Stomatology Hospital of Guangzhou Medical University, Guangzhou 510000, China
  • Received:2019-11-01 Revised:2020-02-13 Online:2020-11-20 Published:2020-09-29
  • Contact: Jianming CHEN

微种植体结合CD矫治器远移上颌磨牙时尖牙位置变化的体外研究

陈建明(),谭媛欢,胡耀政,彭菁   

  1. 广州医科大学附属口腔医院·广州口腔疾病研究所·口腔医学重点实验室,广东 广州(510000)
  • 通讯作者: 陈建明
  • 基金资助:
    广东省科技创新战略专项资金(科技创新普及专题)项目(2020A1414050070)

Abstract:

Objective To investigate changes in the three-dimensional position of the maxillary canine during the distal movement of the maxillary first molar by a mini-implant combined with a CD appliance. Methods Ten typodont models of class II malocclusion were selected, and one side was randomly chosen as the experimental group. The CD appliance was bonded to the maxillary canine and first molar of the experimental group, and 1.2 mm stainless steel wire was bent as the anchorage, which was fixed on the model to simulate mini-implants implanted in the zygomatic alveolar ridge. Then, 180 g orthodontic force was applied to the canine of the experimental group; the other side was recognized as the control group and was not used for strengthening. Six mini-implants were implanted in different parts of the model and used as a reference before and after the experiment. The models were placed in an incubator and heated at 56 ℃in a water bath for 2 min. The models were scanned before and after thermostatic water bath treatment with a 3-shape scanner. Then, the digital models were overlapped through the reference points, and the positions of the canines and first molars were measured before and after the experiment. Results The sagittal movement distance of the first molar in the experimental group was ( 0.25 ± 0.33) mm, and the vertical movement distance was (0.25 ± 0.28 )mm, which was significantly different from the control group (P < 0.05), while the transverse change was not significantly different (P > 0.05). There was no significant difference in the root position of the first molar in the experimental group (P > 0.05). The lateral and vertical displacement distances of the maxillary canine crown in the experimental group were (4.03 ± 2.11) mm and (1.86 ± 1.01) mm, respectively, which were significantly different from those in the control group (P <0.001), while the sagittal changes showed no significant differences (P > 0.05). In the experimental group, there was no significant difference in the position of the apex of the maxillary cusp (P > 0.05). Conclusion Our in vitro study showed that the maxillary canines inclined buccally accompanied by a small amount of intrusion during molar distalization by a mini-implant combined with a CD appliance.

Key words: mini-implant, CD appliance, class Ⅱ malocclusion, anchorage, tooth movement, distal movement, maxillary molars, maxillary canines, three-dimensional position

摘要: 目的 探讨体外微种植体结合CD矫治器推上颌第一磨牙远中移动时,尖牙三维位置的变化。 方法 选择10副安氏Ⅱ类错畸形Typodont模型,随机选取一侧作为实验组,将CD矫治器粘接于实验侧的上颌尖牙与第一磨牙,以直径1.2 mm的不锈钢丝弯制支抗部件,模拟植入颧齿槽嵴的微种植体,并对尖牙施加约180 g的正畸矫治力。而另一侧作为对照组,不加力。随后,在蜡堤模型不同部位植入6个微种植体进行标记,作为实验前后的固定参照物。将Typodont模型放入56 ℃恒温箱中水浴加热2 min,通过3-shape口内扫描仪对实验前、后模型进行全牙列扫描。通过参照物将实验前后的数字模型进行重叠,测量上颌尖牙、第一磨牙三维位置的变化。 结果 实验组第一磨牙牙冠矢状向(远中)移动距离为(0.25 ± 0.33)mm,垂直向移动距离为(0.25 ± 0.28)mm,与对照组相比差异有统计学意义(P < 0.05),而横向变化差异无统计学意义(P > 0.05);实验组第一磨牙牙根根尖位置变化差异无统计学意义(P > 0.05)。实验组上颌尖牙牙冠横向移动距离为(4.03 ± 2.11)mm,垂直移动距离为(1.86 ± 1.01)mm,与对照组相比差异有统计学意义(P < 0.001),而矢状向变化无统计学差异(P > 0.05);实验组上颌尖牙根尖位置变化差异无统计学意义(P > 0.05)。结论 微种植体结合CD矫治器远移上颌磨牙时,上颌尖牙牙冠发生颊向倾斜的同时也伴随少量压低。

关键词: 微种植体, CD矫治器, 安氏Ⅱ类错牙合畸形, 支抗, 牙齿移动, 远中向移动, 上颌磨牙, 上颌尖牙, 三维位置

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