112 EAELY DESTRUCTION OF THE TEETH. 



of the enamel. We also find interstices produced 

 by the crowded position of the teeth and the irre- 

 gularity of their shape. In these situations par- 

 ticles of food are retained, and which cannot be 

 dislodged by means of the tooth-brush on account 

 of the depth of the receptacles ; consequently the 

 portions thus retained undergo a process of decom- 

 position, and acquire the property of an acid, with 

 its power of dissolving the connexion hitherto ex- 

 isting between the earthy and animal matter of 

 which the tooth is composed. 



This is the true cause of the destruction of the 

 teeth. It is not the result of inflammatory action, 

 either in the membrane or the bone. Neither is it 

 necessary that the bone of the tooth should undergo 

 abnormal action to predispose it to chemical action ; 

 because the agent that can effect the destruction 

 of the enamel, will find it less difficult to efiect the 

 destruction of the bone after penetrating the enamel. 

 But, that chemical action is the true cause will 

 appear evident, if we observe the situations where 

 the mischief begins, and take a correct view of the 

 operations necessary to retard, or efiectually to arrest, 

 the evil when it commences. 



The question, then, which I have here to ask 

 is — ^Which are the parts of the tooth where the 

 mischief first begins? We never find an attack 

 made upon the plain and smooth surface of a tooth; 

 there must be a resting-place; and those teeth 

 which present receptacles best adapted for retaining 



