摘要
目的比较不同颅面咬合类型人群中上下切牙的冠长、根长和冠根比,探讨上下切牙的冠根比与颅面形态及其排列方式的相关性。方法选择骨性Ⅰ类安氏Ⅰ类58例(A组)、骨性Ⅱ类安氏Ⅱ类44例(B组)和骨性Ⅲ类安氏Ⅲ类受试者38例(C组),拍摄CBCT,截取相应截面,分别测量上下切牙的冠长、根长,计算冠根比。在CBCT矢状截面上测量颅面类型指标:ANB、SN-MP、Y轴角和前后面高比;上下切牙排列指标:上切牙-PP、下切牙-AP和上下切牙角度。对资料进行统计检验和相关性分析。结果 C组与A、B组上切牙冠长、根长和冠根比均有差异。3组间下切牙冠长、根长无差异,C组与A、B组下切牙冠根比有差异。A、B组间上下切牙冠长、根长和冠根比无差异。3组上切牙根长、冠根比与ANB、Y轴角明显相关。结论上切牙根长和上下切牙冠根比与个体颅面类型及上切牙排列方式有关,可为临床诊断和治疗提供参考。
Objective To measure the length of crown and root and crown-to-root ratio of incisors in subjects of different dentofacial morphology. Methods Fifty-eight subjects of skeletal Class Ⅰ and Angle ClassⅠ （ group A）, 44 subjects of skeletal Class Ⅱ and Angle Class Ⅱ （ group B） and 38 subjects of skeletal ClassⅢ and Angle ClassⅢ（ group C） were included in this study. The crown and root length of incisors was measured with CBCT and the crown-to-root ratio caculated. The cephalometric variables ANB angle, SN-MP angle, Y axis, facial height ratio and the position of incisors （ including upper incisor-palatal plane angle,lower incisor-AP angle and the interincisal angle ）were also examined. Results There was significant difference in the length of crown and root, the crown-to-root ratio of upper incisors and in the crown-to- root ratio of upper and lower incisors between group C and group A, and group C and group B. There was no significant difference in the length of crown and root of lower incisors among the three groups. Correlation analysis revealed that the root length of upper incisors and the crown-to-root ratio were associated with ANB angle and Y axis. Conclusion The crown- to-root ratio of both upper and lower incisors and the root length of the upper incisors were associated with craniofacial morohology and the arrangement of the upper incisors.
出处
《北京口腔医学》
CAS
2013年第4期227-229,共3页
Beijing Journal of Stomatology
关键词
CBCT
切牙
冠长
根长
颅面形态
CBCT
Incisor
Crown and root length
Crown-to-root ratio
Craniofacial morphology
