120 EARLY DESTRUCTION OF THE TEETH. 



extremely liable to become carious, from their zigzag 

 position, and from the one tooth standing before the 

 other ; and even when the teeth are regular, food 

 will be found lodging in their interstices, if the 

 gums have partly receded. 



The patient is therefore instructed to brush them 

 upwards and downwards, as the best mode for 

 removing the destructive matter. His attention is 

 also directed to the masticating surfaces of the 

 double teeth, and he is told to apply the brush 

 firmly across them ; and if he cannot succeed in 

 reaching the bottom of the pits, and so dislodging 

 the remains of the food, then the defect must be 

 at once remedied by the art of the dentist. 



Such is the advice which is or ought to be given. 

 And I hold it to be strictly in accordance with the 

 theory, that chemical action is the exciting cause of 

 the destruction of the teeth. If inflammation of 

 the internal membrane or of the bone were the 

 exciting cause, the pain which always accompanies 

 inflammation would be previous to the commence- 

 ment of decay ; and our patients would be consult- 

 ing us whilst the tooth was yet in a sound state, 

 for the purpose of having the pain removed, and 

 decay prevented by subduing the inflammation. 



But very few such cases come under our notice. 

 On the other hand, I myself have not met with 

 more than two or three cases that I could not trace 

 to inflammation of the periosteum, or to the 

 exposure of the internal membrane occasioned by 



