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A MANUAL OF DENTAL ANATOMY. 



THE CEMENT ORGAN. 



Cementum is, according to these authors, developed, just 

 as bone is, in two distinct methods. 



Where it is not to be very thick, and is to clothe roots, 

 the ossification takes place in membrane (the alveolo 

 dentar periosteum), but where it is to form a thick layer 



over the crown, as in Ruminants, a cartilaginous cement 

 organ is formed, and we have a calcification analogous to 

 formation of bone in cartilage. 



Thus the cement organ is found in those animals only 

 which have coronal cement, such as the Herbivora. In a 

 calf embryo about the time that dentine calcification is 

 commenced, there may be distinguished beneath the follicle 

 wall and above the enamel organ a greyish layer of tissue, 

 thick enough to be distinguishable with the naked eye, and 

 of firmer consistence than the enamel organ, from which it 

 also differs in being richly vascular. 



(!) Cement organ of a calf (after Magitot). a. Fibroid matrix. 

 6. Cartilage cells and capsules. 



