恒前磨牙牙根形态及侧枝根管研究

Morphology of Roots and Lateral Root Canals in Premolar

用双重墨汁渗透牙髓腔根管,脱钙透明法观察前磨牙拔牙标本180颗。结果表明根长平均值介于国内与国外报告值之间。4组牙弯根率平均为34.08％,侧枝根管占57.78％,上颌前磨牙>下颌前磨牙。钙化闭塞根管占18.64％,上颌第一前磨牙>第二前磨牙。

One hundred and eighty extracted premolars were observed with pulp cavity and root canal permeated with Chinese ink and premolars decalcified and transparented. Results showed that the aver- age value of root length was between those at home and abroad. Four groups of curved roots were 34. 08% on the average, lateral roots canal amounted to 57. 8%, and the upper premolars were more than the lower. The rate of calcified obliteration occupied 18. 6%, and the first-premolars were more than the second.