Kumar K V Sujan, Umashankar K, Kumar D Pradeep, Kumar D Praveen
Department of Orthodontics and Dentofacial Orthopedics, MNR Dental College, Sangareddy, Hyderabad, Andhra Pradesh, India.
J Contemp Dent Pract. 2012 Nov 1;13(6):799-805. doi: 10.5005/jp-journals-10024-1232.
The aim of this study is to evaluate the efficiency of canine distraction and also to evaluate the position of canine in the arch after distraction.
The study sample consisted of five patients, (4 males and 1 female), in the age group of 14 to 25 years who needed canine retraction (ten maxillary canines including both left and right) and first premolar extraction as their treatment protocol were included in the study. This study used a in-house manufactured periodontal ligament distractor.
The maxillary canines were distracted distally by 6.42 mm in three and half weeks with a distal tipping of around 15.1° and the maxillary first molars tipped mesially by an average of 6.1°. The maxillary canines rotated mesiobucally by an average of 7.8° bilaterally.
Canines can be distracted rapidly with minimal effects on the vitality and the periodontal condition and almost all of extraction space can be used for anterior dental alignment or retraction. Maxillary canines can be rapidly retracted into the first premolar extraction space at the rate of about 2.43 mm per week.
The overall treatment time is reduced as the time taken for retraction of canine is decreased considerably from 6 and 8 months to 3 weeks. Also there is no significant anchorage loss during this period and is well suitable for cases with group a anchorage where the whole extraction space is needed for retraction of anterior teeth.
本研究旨在评估犬齿牵引的效率,并评估牵引后犬齿在牙弓中的位置。
研究样本包括5名患者(4名男性和1名女性),年龄在14至25岁之间,需要进行犬齿后移(包括左右两侧共10颗上颌犬齿)且治疗方案为拔除第一前磨牙,这些患者被纳入研究。本研究使用了自行制造的牙周膜牵引器。
上颌犬齿在三周半的时间内向远中牵引了6.42毫米,远中倾斜约15.1°,上颌第一磨牙平均向近中倾斜6.1°。上颌犬齿双侧平均向近中颊侧旋转7.8°。
犬齿可以快速牵引,对活力和牙周状况影响最小,几乎所有拔牙间隙都可用于前牙排齐或后移。上颌犬齿可以以每周约2.43毫米的速度快速后移至第一前磨牙拔牙间隙。
由于犬齿后移时间从6至8个月大幅缩短至3周,整体治疗时间减少。在此期间也没有明显的支抗丧失,非常适合需要利用整个拔牙间隙后移前牙的A类支抗病例。