Department of Dental and Maxillofacial Radiology, Independent Unit of Epidemiology, Medical University of Lublin, Lublin, Poland.
Eur J Orthod. 2011 Oct;33(5):492-7. doi: 10.1093/ejo/cjq123. Epub 2011 Jan 24.
The aim of the study was to determine whether there are differences in dental age (DA) using the method of Demirjian, in patients with impacted buccal or palatal maxillary canines in relation to unaffected controls. DA was estimated using Demirjian's method on panoramic radiographs of two groups of Caucasian patients. The study group consisted of 116 patients aged from 12 to 16 years (80 females and 36 males) that was further divided into 54 patients with unilateral or bilateral palatally impacted maxillary canines and 62 patients with buccally positioned canines. The control group of 116 subjects without canine impaction was matched to the study group by age and gender. Calculated DAs and differences between dental and chronological age (CA) were compared between the groups. Statistical analysis was performed using Shapiro-Wilk, Mann-Whitney U, and Student's t-test. DA was significantly lower in patients with impacted maxillary canines than in healthy controls and also when palatal or buccal ectopia was considered. The rate of dental development in patients with palatally impacted canines did not differ from that of subjects with buccal canine displacement. The differences between DA and CA were higher in healthy controls (increase in DA) than in patients with impacted maxillary canines. DA estimation using Demirjian's method may be lower than expected in subjects with maxillary canine impaction.
本研究旨在通过德米热里安（Demirjian）法评估牙齿年龄（DA），确定上颌颊侧或腭侧埋伏阻生的尖牙患者与正常对照者的 DA 是否存在差异。在两组高加索患者的全景片上，使用德米热里安法估计 DA。研究组包括 116 名年龄在 12 至 16 岁的患者（80 名女性和 36 名男性），其中 54 名患者为单侧或双侧腭侧埋伏上颌尖牙，62 名患者为颊侧尖牙。对照组为 116 名无尖牙阻生的患者，按年龄和性别与研究组匹配。比较各组间计算出的 DA 和牙龄（CA）与实际年龄（CA）的差异。使用 Shapiro-Wilk、Mann-Whitney U 和 Student's t 检验进行统计分析。与健康对照组相比，上颌埋伏尖牙患者的 DA 明显较低，且考虑到颊侧或腭侧异位时也是如此。腭侧埋伏尖牙患者的牙齿发育速度与颊侧尖牙移位患者无差异。健康对照组的 DA 与 CA 之间的差异（DA 增加）高于上颌埋伏尖牙患者。使用德米热里安法评估 DA 时，上颌埋伏尖牙患者的 DA 可能低于预期。
