a Senior Consultant, Department of Orthodontics, Postgraduate Dental Education Center, Orebro, Sweden.
Angle Orthod. 2014 Jan;84(1):3-10. doi: 10.2319/031013-205.1. Epub 2013 Jun 18.
To evaluate the effect of the extraction of deciduous canines on palatally displaced canines (PDCs), to analyze the impact of the age of the patient on this interceptive treatment, and to assess the outcome of one-sided extraction of a maxillary primary canine on the midline of the maxilla.
This study included 48 PDCs in 24 consecutive patients with bilateral PDCs. The mean age of the patients at diagnosis was 11.6 years (standard deviation 1.2 years). After randomization, one deciduous canine of each patient was assigned to extraction, and the contralateral side served as control. The patients were then followed at 6-month intervals for 18 months with panoramic and intraoral occlusal radiographs.
The rates of successful eruption of the PDCs at extraction and control sites were 67% and 42%, respectively, at 18 months. The difference between the sites was statistically significant, and the effect was significantly more pronounced in the younger participants. A significant decrease in arch perimeter occurred at extraction sites compared to control sites during the observation period. No midline shift toward the extraction side was observed in any patient.
The extraction of the deciduous canine is an effective measure in PDC cases, but it must be done in younger patients in combination with early diagnosis, at the age of 10-11 years. Maintenance of the perimeter of the upper arch is an important step during the observation period, and a palatal arch as a space-holding device is recommended.
评估拔除乳牙对腭侧错位恒尖牙(PDC)的影响,分析患者年龄对此预防性治疗的影响,并评估单侧上颌乳尖牙拔除对上颌中线的影响。
本研究纳入了 24 名双侧 PDC 连续患者的 48 颗 PDC。患者诊断时的平均年龄为 11.6 岁(标准差 1.2 岁)。随机分组后,每位患者的一颗乳牙被分配到拔牙组,对侧为对照组。然后,患者每隔 6 个月进行 18 个月的随访,拍摄全景和口腔咬合射线片。
18 个月时,拔牙组和对照组 PDC 成功萌出率分别为 67%和 42%。两组间差异具有统计学意义,且在较年轻的患者中效果更为显著。与对照组相比,观察期间拔牙组的牙弓周长显著减小。在任何患者中均未观察到中线向拔牙侧的偏移。
拔除乳牙是 PDC 病例的有效措施,但必须在 10-11 岁时结合早期诊断,在年轻患者中进行。在观察期间保持上颌牙弓周长是一个重要步骤,建议使用腭弓作为保持间隙的装置。