中文摘要：

目的分析中国现代人群颏形的表现特点及时代变异。方法将颏形分为3种类型，方形、圆形、尖形，比较不同时代间（新石器时代54例，青铜铁器时代197例，近代113例）各个类型出现率的差异。结果新石器时代颏形主要为圆形和方形，青铜铁器时代圆形颏形占绝对优势，近代主要为圆形。中国晚期智人颏形为圆形和尖形。结论颏形不同时代间有差异，颏形的变化可能与下颌骨尺寸、下颌前部形态的时代变异有关。

英文摘要：

Objective To understand the variation in the chin form of Chinese population. Methods This study was conducted on 364 human mandibles from China. Chin form is divided into 3 types： straight, round and protruding, and comparisons were made among different time periods. Results The ＂round＂ and ＂straight＂ were the two main chin forms in Neolithic age, while most were ＂Round＂ in Bronze-Iron age and present. The frequency of ＂straight＂ was the highest in Neolithic age, and the lowest in Bronze-Iron age. Conclusion The chin form varies in different time periods, which may be caused partly by the size variation of mandibles.