130 ON THE CHEOPLASTIC METHOD 



swaging up the plate, wliix?li can only be partially 

 avoided by using a number of dies, and even this 

 attended by the possibility of considerable varia- 

 tion in the dies as compared with each other. 



The difficulties consequent upon soldering, &c. 

 such pieces are too well known to require repe- 

 tition, but which increase the obstacles found in 

 obtaining a correctly fitting denture from a struck 

 plate. The great skill and beauty displayed in 

 the carving of bone pieces do not, from limited 

 observation, obviate the objections to struck plates 

 in this particular, besides having other more 

 serious objections, such as perishability and want 

 of perfect cleanliness. 



The process known as hard rubber, and intro- 

 duced to the American practice by a Mr. Wheat, 

 is a better process for this end, although not by 

 any means perfect, as in the manipulation the 

 delicate corrugations of the cast are often rubbed 

 down, and the pressure of the screw used to force 

 the one part down in the other, is often attended 

 by a displacement or injury of surface, in spite of 

 the greatest care, as also the great tendency of 

 this material to spring and warp from slight heat 

 and small pressure, must greatly mar and inter- 

 fere with a perfect result, if it were even attended 

 by all other perfections. 



The process which is now about to be intro- 

 duced to your consideration has been denominated 

 cheoplasty, or a means by pouring, being a 



