英语语法分析

Expasyl: a new material for gingival retraction-Clinical application.

一种新型排龈材料的临床应用。

A rubber dam is needed to prevent the superoxol from burning the gingival.

需要做个橡皮障免得牙龈被烧伤了。

Bacteria are the primary cause of irritation and inflammation to the gingival.

细菌是牙龈受到刺激和感染的主要原因。