离体牙牙冠表面各部位电阻的测量

Measurement of the value of electric resistance of crown surface in vitro

目的：研究牙冠表面电阻状态。方法：选用了４５个新鲜离体牙，测量其牙冠表面各点与牙髓间的电阻。结果：在牙尖部位的电阻值最高，且与其他部位相差显著；颈部釉质处电阻值次之，并与合面窝沟、牙颈部釉牙骨质界处的电阻值相差显著；合面窝沟、牙颈部釉牙骨质界处的电阻值较低。结论：牙体表面各部位的电阻值有很大的差异。

Aim: To study the electric resistance of the crown surface of tooth. Methods: 45 freshly extracted molar teeth, without any lesion and caries, were selected. The electric resistance values at four spots of each cusp, pit and fissure, cervical enamel, cervical cementum of each tooth, were measured respectively. Results: The average electric resistance value of cusp was the highest, and it was significantly different from that of the other sets of the crown surface; the electric resistance value of cervical enamel was next to that of cusp, and it was also significantly different from that of pit and fissure, cervical cementum respectively. Conclusions: The electric resistance of each set of crown surface of tooth is greatly different from each other respectively.