VITAMIN C 165 



that changes could be noted in the teeth during the second week and 

 in the lower jaw and ribs during the third week. The progressive 

 changes taking place in the teeth were considered to be as follows : ( 1 ) 

 Gradual changes of the odontoblast layer; (2) Amorphous calcification 

 of the predentin; (3) Widening of Tome's canals in the dentin formed 

 before the onset of scurvy; (4) New formation of bone instead of 

 dentin, the new bone first forming a thin layer inside the calcified 

 predentin and then extending toward the center of the pulp as a 

 spongy porous mass; (5) Dilatation of the vessels and, in the early 

 stages, hyperemia with occasional hemorrhages into the pulp; (6) 

 Atrophy and resorption of the pulp tissue, sometimes going so far as 

 to leave large hollows filled with fluid. 



In Hojer's opinion the tooth picture is determined not so much by 

 the time during which the guinea pig has been deprived of vitamin C 

 as by the extent of the deprivation. The changes in tooth structure 

 evident in guinea pigs which had received about seven-tenths of 

 the minimal protective dose of orange juice for 22 and 92 days, re- 

 spectively, were similar, but the condition was unlike that in other 

 guinea pigs which had received eight-tenths of the protective dose for 

 similar periods of time. In Hojer's opinion the condition most likely 

 to be met in human beings is that developing when at least half of 

 the necessary amount of antiscorbutic is provided. In guinea pigs on 

 such a dosage the dentin is irregular with ridges of hard tissue. This 

 is also the condition during the early stages of healing of severe 

 scurvy. 



Discussing the opinions of other investigators concerning the changes 

 taking place in the teeth, Hojer agreed with Zilva and Wells and 

 with Toverud that the changes begin in the crown part of the pulp 

 and spread toward the root, but took exception to their theory of 

 fibroid degeneration. In his opinion a few cells may degenerate, but 

 the change is primarily from active odontoblast to active osteoblast 

 cells — not necrosis but newly formed bone. In Hojer's opinion this term 

 should be applied only to the irregular dentin formed when the tooth 

 is being reorganized by reappearing odontoblasts or under conditions 

 of partial deprivation of antiscorbutic. 



The changes noted in the bones, although appearing later than those 

 in the teeth, were thought to be of similar character. The new pathologi- 

 cal bone, although porous and spongy, showed less diflferentiation than 

 normal. No evidence could be obtained, however, of an altered pro- 

 portion of calcium in the bones. In healing, the osteoblast layers gradu- 

 ally resume their normal appearance provided the dosage of antiscorbutic 



