Etching time has been extended in wet etching course.

在湿法刻蚀诱导坑时，需适当延长刻蚀时间。

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Objective: the aim of the study was to investigate the effects of different etching time on shear bonding strength to guide its clinical use.

目的：研究不同酸蚀时间和不同施力方向对正畸托槽与牙面间剪切强度的影响。

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Objective:To investigate the appearance of enamel on the cross section of tooth after etched with 37% phosphoric acid for different etching time .

目的：观察用37%磷酸凝胶以不同酸蚀时间处理后的牙釉质在牙齿横断面上的形态改变。

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This method allows better control of the thicknesses of the silicon and glass layers, but the etching is time-consuming and requires the costly sacrifice of a wafer for each one that is made.

ECONOMIST: Chip technology