PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION, 473 



The science of dentistry, practically speaking, should be 

 divided into two branches, mechanical and surgical ; to the 

 former belongs the insertion of artificial teeth, to the latter 

 operations upon living teeth. One individual usually practices 

 both these branches, which is wrong, and prevents them from 

 arriving at perfection in either. 



Cleansing the teeth with instruments is necessary when foreign 

 substances, such as tartar, &c., adhere to them, which invariably 

 excites an unhealthy action in the peosteum and gums, and if 

 not eradicated will in time loosen the teeth and cause them to 

 fall out. Not longer ago than yesterday a fine, hale, healthy- 

 looking man complained to me that his teeth had nearly all come 

 out, one after another, in a perfectly sound state. I considered 

 this remarkable, and asked him to let me look in his mouth, when 

 the cause became manifest. Those remaining were completely 

 covered with tartar, and he confessed that he had never cleaned 

 his teeth. 



Mal-practice to a great extent once prevailed among dentists 

 who cleaned teeth with instruments, consisting in wounding the 

 enamel ; this unpardonable error seldom occurs now. Many 

 teeth are destroyed by the use of powders containing acids and 

 hurtful chemical agents, which decompose the agglutinating 

 principle by which their bony substances are combined together. 

 Charcoal rendered fine, or chalk, are probably the most simple 

 and best dentrifices that can be used. A hard brush dipped in 

 luke warm water and covered with either of the substances 

 named may be used before breakfast, perpendicularly, longitudi- 

 nally, internally and externally, and after breakfast a soft brush 

 with plain water will be sufficient. The same may be used before 

 retiring at night. 



Extracting teeth is a performance that requires great skill, 

 and judicious application of the forceps ; which should always 

 be used instead of the turnkey, from the awkward and careless 

 use of which latter instrument, fatal consequences have often 

 resulted. 



If the laws of digestion were not violated, it would probably 

 be unnecessary either to pull, or file teeth, which receive their 

 first injury from the digestive organs when the stomach is over- 

 loaded with indigestible animal food, the gums become soft, and 

 all the other membranes of the mouth diseased, which produces 

 incipient decay in the teeth, hot tea, coffee, and viands generally, 



