Effect of Treating Agents to the Exudation of Internal Fluids from Dentinal Tubules

采用精密复制的方法，在牙本质表面上观察了牙本质小管内部液体的渗出，并研究了蚀刻对渗出的影响。结果如下：1。在人新拔牙和活牙的牙本质表面观察到许多圆形突起。印模表面的圆形和小凹坑必须是在设置过程中由牙本质小管内部流体的渗出压力形成的，以表明这些圆形突起的存在。本法在离体和体内均能有效地观察牙本质小管内液的渗出情况。使用快速固化时间为2分钟的印模材料时，未蚀刻的牙本质表面也有渗出物。随着印模材料凝固时间的延长，未蚀刻牙本质表面的渗出物数量增加，而使用快速凝固时间为2分钟的印模材料时，在蚀刻牙本质表面未观察到渗出物。使用固化时间较长的印模材料时，牙本质表面也有渗出物。牙本质蚀刻去除涂污层可以有效延缓和减少牙本质小管内部液体的渗出。这些延迟和减少的渗出物对于树脂材料与牙本质的良好粘附是有效的。

Exudation of internal fluids from dentinal tubules on the freshly extracted and vital humans teeth was observed and the effect of etching to the exudation was studied on the ground dentin surfaces by SEM observation using precision replica method. Results were as follows :1. Many round prominences were observed on the dentin surfaces of the freshly extracted humans teeth and the vital humans teeth. The round and small concavities on the impression surfaces must be formed by the exuding pressure of the internal fluids from dentinal tubules during the setting to indicate the presence of these round prominences. This method was effective for observing the exudation of internal fluids from dentinal tubules in vitro and in vivo.2. The exudation was also observed on the unetched dentin surfaces when the impression material with fast setting time of 2 minutes was used. The quantity of exudation on the unetched dentin surfaces increased according to the prolonged setting time of the impression material But the exudation was not observed on the etched dentin surfaces when the impression material with the fast setting time of 2 minutes was used. The exudation was also observed on the etched dentin surfaces when the impression material with prolonged setting time was used. Etching of dentin to remove the smeared layr was effective to delay and lessen the exudation of internal fluids from dentinal tubules. These delay and decrescence of the exudation must be effective for the favorable adhesion of resinous materials to dentin.