CHAPTER LXXIII 



THE MICROBE OF DECAYING TEETH 



EVERY permanent tooth in the human jaw is sur- 

 rounded by an enamel covering. Nature forms 

 this covering to protect the inward parts of the 

 tooth, the dentine and pulp. It is beautifully 

 adapted to this service, as hard and white as 

 ivory. 



Microbes cannot penetrate this protective shield. 

 So long as it remains whole and perfect, the tooth 

 is* healthful and sound. But the moment any little 

 fracture of the enamel occurs, it is an open door 

 for the entrance of bad germs to the inner parts of 

 the tooth. These germs come into the mouth from 

 the atmosphere, are always ready to enter any and 

 every breakage of the tooth's covering. Once in 

 the wound, they Uere grow, multiply, and by their 

 life processes generate the putrefactive poison 

 which causes the decay and death of the tooth. 



All the woes of teethache, ulcerations, and loss 

 of teeth, are owing to the work of these germs. 



And yet all this is preventable! Preserve the 

 covering of the teeth. Keep out the foes. That's 

 all. 



Possibly this cannot always be done perfectly; 

 but, with patience and scrupulous care, it can be 



252 



