OF CASES OP CLEFT PALATE. 11 



removed from the mouth, are dragged away by the 

 inclining teeth, often to so great an extent as to 

 render the impression worthless. Of all sub- 

 stances, gutta-percha appears the one best adapted 

 for the purpose ; but, until I had recourse to the 

 fitted plate instead of the ordinary metal tray, I 

 found the impressions taken in this material very 

 indistinct and unsatisfactory. The heat required 

 to soften a thick roll is too great to be endured 

 patiently in the mouth ; yet, if employed less 

 heated, the impression is very defective ; but, by 

 using a thin sheet a quarter of an inch, or even 

 less, in thickness, on a plate previously fitted to 

 the mouth, it proves itself to be a most valuable 

 agent. 



It is scarcely necessary to describe the way it 

 should be used. A piece is cut to fit the plate, 

 which should be roughened on the surface on 

 which the gutta-percha is to rest; and when 

 thoroughly softened in water, it is laid in the 

 plate which has been previously warmed, and both 

 are carried into the mouth. The plate should 

 be pressed steadily into its place, and retained 

 there by a finger on either side of the jaw : in 

 about a minute the whole may be removed. The 

 gutta-percha will be found to have yielded to the 

 inclining teeth as it passed over them in coming 

 out, but to have returned to the shape it first 

 received in the mouth. 



A new material has recently been introduced 



