中文摘要：

目的调查分析江苏地区错畸形患者中牙齿发育不全（先天性牙齿缺失、多生牙、埋伏牙及融合牙）的发生和分布情况,为临床工作提供参考。方法收集2012年6月—2012年9月在我院正畸科治疗的初诊患者1 012例（男416例,女596例,年龄4～50岁）,根据影像资料、临床检查、病史信息统计先天性牙齿缺失、多生牙、埋伏牙、融合牙的发病情况及其在牙列中的分布情况。结果本研究中,先天性牙齿缺失（不包括第三磨牙缺失）的发生率为8.99%,最常见的缺失牙位是下切牙;多生牙的发生率为2.57%,最常在上颌中切牙腭侧多生并埋伏;埋伏牙的发生率为8.79%,最常见于上颌尖牙埋伏;融合牙的发生率为0.69%,均发生在下颌前牙区。结论江苏地区正畸患者的牙齿发育不全的发生率较高,以先天性牙齿缺失最为多见,发生率明显高于既往流行病学研究结果的平均水平,其次为埋伏牙、多生牙以及融合牙。

英文摘要：

Objective To investigate prevalence and distribution of tooth agenesis（congenitally absent teeth,supernumerary teeth,impacted teeth and fused teeth） in a sample of patients who had malocclusion in Jiangsu area to support clinical work.Methods 1012 orthodontic patients at the first visit in Jiangsu Provincal Stomatological Hospital（416 males,596 females,aged between 4 to 50 years） from June to September of 2012 were collected.Based on the radiography data,clinical examination and medical history,analyze the prevalence of congenitally absent teeth,supernumerary teeth,impacted teeth and fused teeth and their distribution in dentition Results The prevalence of congenitally hypodontia was 8.99 %（excluding the third molars）,and the most frequent missing tooth position was lower incisor.The prevalence of supernumerary teeth was 2.57%,and most of them were located in palatal of upper central incisors and were impacted.The prevalence of impacted teeth was 8.79%,occurred most frequently in the maxillary canine.The prevalence of fused tooth was 0.69%,and all cases were in mandibular anterior teeth.Conclusions There′s a high prevalance of tooth agenesis in orthodontic patients in Jiangsu Province,and congenitally absent teeth were most common,whose prevalence was significantly higher than average result in previous epidemiological studies.Impacted teeth come the second.Supernumerary teeth and fused teeth follow.