NAMEL 



DENTINE 



BLAST LAYER 

 EL ORGAN OF 

 LK TOOTH ) 

 EPITHELIUM OF GUM 



ODONTOBLAST LAYER 



(DENTINE ORGAN 



OF TOOTH) 



CELLS Of INNER 

 LAYER OF DENTAL 

 SAC FORM THE 

 CEMENTOBLAST 

 LAYER WHICH 

 DEPOSITS CEMENTUM 

 PULP 



DENTINAL FIBERS 



CELLS OF OUTER 

 LAYER OF DENTAL 

 SAC FORM BONE 



SPACES OF MANDIBLE 



BONE OF MANDIBLE 



Fio. 286. Development of thecodont teeth. (A) Early stage of developing premolar 

 of human. (B) Cellular relationships of tooth-forming area greatly magnified. (C) 

 Later stage in tooth development showing dental sac. (D) Vertical section of erupting 

 milk tooth. (E) Vertical section of canine tooth, in situ. (Redrawn and modified from 

 Morris, 1942, Human Anatomy, Blakiston, Phila. After Toldt.) 



610 



