34 EXCLUDING MOISTURE FROM TEETH, ETC. 



gauze, or even tissue-paper, may be used as a medium 

 for holding together the soluble and insoluble com- 

 ponents, which we have hitherto failed to unite, ex- 

 cepting by the interposition of some fibrous material. 

 When operating upon the front teeth from the 

 lingual surface, a strip of membrane may be laid 

 upon the anterior surface of the teeth and gums 

 with advantage. The lip may then be allowed to 

 fall into its place without any chance of moisture 

 finding its way between the faulty teeth ; and when 

 the gold is introduced from the anterior surface, the 

 strip should be applied upon the lingual surface. 

 But the manner of using the membrane is too 

 obvious to need any detailed explanation. I may, 

 however, remark that it is necessary to secure 

 perfect adhesion of the membrane before the opera- 

 tion is commenced. The adhesive material is, of 

 course, soluble, and would soon be washed away, but 

 for the protection afibrded by the layer of gutta- 

 percha. When adherent to the gums and teeth, 

 the thin edge is alone exposed to the solvent action 

 of the saliva, and the action upon the mere edge is 

 too slow to produce any mischievous result. 



