THIRTY YEARS. 



121 



Fig. 124. 



Thirty Years (Figs. 122, 123, 124).— This plate shows the char- 

 acter of extreme old age. In front, the superior incisive arch overlaps 

 the inferior, which has become consicleral)ly narrower ; the convergence 

 of the corner and intermediate teetli be(*()ines more marked. In [)rofile, 

 the inferior incisors are almost horizontal, esi)ecially the corner ones; 

 the jaws are thinned and are wider apart from each other in the region 

 of the bars. The tables of the inferior teeth nre flattened from side to 

 side (biangnlar). The peripheral enamel has almost disappeared from 

 the posterior border of the teeth. In the upper jaw the tables are flat- 

 tened from side to side nnd the enamel is nearly worn away. Sometimes 

 in one or in both jaws the teeth have acquired an extreme length and 

 are not leveled ; or, at other times they are worn away almost to the 

 roots and leyel with the gums, and are surrounded by a large deposit 

 of the radical cement which covers the dentine, while the enamel has 

 entirely disappeared. 



