THE PERMANENT DENTITION. 



209 



PERMANENT DENTITION. 



The permanent teeth are well developed and pressing on 

 the roots of the temporary ones before the latter are shed. 



Fig. 192 illustrates the jaws of a child about six years of 

 age, in which the relations of the two sets of teeth are shown,— 

 the temporary teeth still in position, and the sixth-year molars 

 just erupting. The permanent incisors, both upper and lower, 

 — which, after the *sixth-year molars, are the next to erupt, — are 

 the most advanced, both as to completeness of form and as to 



Fig. 192. 



position. The canines, which are not due until the child is 

 between eleven and thirteen years of age, are not nearly so 

 •complete in form nor so far advanced toward eruption. 



The permanent teeth appear in the following order : — 



First molars,. . . . . . . 5 to 6 years. 



Central incisors, 6 to 8 years. 



Lateral incisors, 7 to 9 3^ears. 



First bicuspids, 9 to 10 years. 



Second bicuspids, . . . . . . 10 to 11 3'ears. 



Canines, . . . * . . . 11 to 13 years. 



Second molars, 12 to 14 years. 



Wisdom-teeth, 17 to 21 years. 



14 



