中文摘要：

目的：测量记录2000年前人牙内陷上颌侧切牙根管长度和直径，计算根管锥度，并与正常上颌侧切牙比较。方法：选取牙内陷上颌侧切牙21个（畸形组）和正常上颌侧切牙12个（正常组）。用Micro-CT进行扫描，Mimics软件重建，测量根管长度和不同部位根管直径，计算根管锥度；进行统计分析。结果：两组间根管长度的比较差异无统计学意义（P〉0．05）；根管直径的比较：两组间颊舌向根中1／3处、颊舌向和近远中向根尖孔处间的差异均有统计学意义（P〈0．05）。根管锥度的比较：畸形组颊舌向各段间的差异均无统计学意义（JP〉0．05）；近远中向尖段与冠段、中段间差异均有统计学意义（P〈0．05）；正常组颊舌向和近中远中向各段间差异均有统计学意义（P〈0．05），两组间各段根管锥度间差异均无统计学意义（P〉0．05）。结论：2000年前人牙内陷上颌侧切牙与正常上颌侧切牙间根管形态有差异，牙内陷可引起牙根管形态的变化。

英文摘要：

AIM： To investigate the root canal anatomy of normal maxillary lateral incisors and maxillary lateral incisors with dens invaginatus of ancient Chinese individuals of 2,000 years ago. METHODS ： 12 normal per- manent maxillary lateral incisors and 21 abnormal ones with single-rooted-canal were scanned by Micron-CT and re- constructed respectively by Mimics 10.01. software. The canal length was measured. For each cross section of the ca- nals, bucco-lingual （BL） and mesion-distal （MD） diameters of each canal were measured at cervical, middle and apical 1/3 sections of the canals by software Mimics. The taper of the canals was calculated and analyzed. RESULTS ： Difference was not found between the canal lengths of the two groups （P 〉 0.05）. There were differences in canal BL diameter at the middle, MD and BL diameters at the apical foramens betwent the two groups （P 〈 0.05）. In dens in- vagination group, there was no taper difference among the three sections in BL direction, there was difference between apical and cervical sections （P 〈 0.05 ）, as well as between the apical and middle sections （ P 〈 0.05 ）. In normal