CEMENT 



303 



A moulding or shaping process appears to take place, the 

 osteoblasts apparently laying down more tissue than is 

 eventually required and the osteoclasts removing the super- 

 fluous material. This double action of the formative cells 

 of the cement can be well seen in fig. 216, where osteo- 

 blasts are laying down the tissue, and large giant cells are 

 absorbing it on their inner side. 



Many authorities, especially the French histologists, deny 

 the existence of a distinct absorbent organ, and look upon 



FIG. 198. Absorption of dentine and re-deposit of cemental 

 tissue. Weil process. (x!50.) 



the absorption of the temporary teeth as a physiological 

 process of rarefying osteitis, in which absorption and deposi- 

 tion alternate. This view is held by Redier, Malassez, and 

 Galippe, and was embodied in a paper contributed to the 

 International Dental Congress of 1910 by J. Choquet, who 

 came to the same conclusion from his own researches (3). 

 As Professor Sims Woodhead states (10), * Rarefying osteitis 

 must be looked upon as a process rather than a distinct 

 disease ' ; and again on p. 477 : 'In rarefying osteitis there 

 is increased absorption of bone accompanied by a corre- 

 sponding new formation.' 



That such a process does occur in temporary teeth is 



