Kumar Priyanka Sethi, Saxena Ruchi, Patil Sameer, Keluskar Kanhoba Mahabaleshwar, Nagaraj K, Kotrashetti Sharadindu M
Department of Orthodontics and Dentofacial Orthopedics, Santosh Dental College and Hospital, Ghaziabad, India.
Aust Orthod J. 2009 Nov;25(2):147-52.
To investigate rapid canine distalisation by periodontal ligament distraction and to determine the effects of periodontal ligament distraction on the canine root and pulpal vitality.
The sample consisted of 16 upper canines in eight patients who required first premolar extractions. The upper first premolars were extracted and the interseptal bone distal to each canine was thinned and undermined surgically. Custom-built distractors were placed and activated immediately to distract the canines into the extraction spaces. Radiographs were taken before canine distraction and at regular intervals thereafter. The upper canine pulps were tested with an electronic pulp tester before and after the distraction and the canines were examined on the post-distraction radiographs for evidence of apical and lateral root resorption.
The canines were retracted to proximal contact with the second premolars in 20.33 +/- 1.87 days. The average amount of retraction was 5.25 mm and the canines tipped distally 15.33 degrees. Although the upper molars did not move mesially, they extruded almost 1 mm. Root resorption was minimal and there was no deterioration in pulp vitality.
Canines can be rapidly retracted by periodontal ligament distraction without complications. However, the efficacy of the method depends upon the surgical procedure, which is technique sensitive. Resistance offered by the interseptal bone distal to the apex of the canine was thought to be the reason for the canine tipping during distraction.
通过牙周膜牵张研究犬齿快速远中移动，并确定牙周膜牵张对犬齿牙根及牙髓活力的影响。
样本包括8例需要拔除第一前磨牙患者的16颗上颌犬齿。拔除上颌第一前磨牙，并通过手术将每颗犬齿远中的牙槽间隔骨削薄并掏空。放置定制的牵张器并立即激活，将犬齿牵入拔牙间隙。在犬齿牵张前及此后定期拍摄X线片。在牵张前后用电子牙髓活力测试仪测试上颌犬齿牙髓，并在牵张后X线片上检查犬齿有无根尖及侧方牙根吸收。
犬齿在20.33±1.87天内被牵至与第二前磨牙近中接触。平均牵张量为5.25mm，犬齿远中倾斜15.33度。尽管上颌磨牙未向近中移动，但几乎伸长了1mm。牙根吸收极少，牙髓活力无下降。
牙周膜牵张可使犬齿快速后移且无并发症。然而，该方法的疗效取决于手术操作，而手术操作技术要求较高。犬齿根尖远中牙槽间隔骨提供的阻力被认为是牵张过程中犬齿倾斜的原因。
