, CHAPTER IV 

 DENTINE 



THE bulk of the human tooth, as well as that of the 

 teeth of other mammalia and many vertebrates, consists 

 of dentine, and although found throughout the animal 

 kingdom in many different forms, this tissue has certain 

 common characteristics which clearly separate it from 

 the other hard tissues of the teeth. In distinction from 

 enamel it has a collagen basis, and when subjected to the 

 action of acids this gelatinous substance retains the form of 

 the calcified dentine. In this respect it resembles bone, 

 but there are differences in structure in all the different 

 varieties of dentine which distinguish it as a special tissue 

 peculiar to the teeth and dermal appendages. 



The form of dentine found in the human tooth, and the 

 teeth of mammalia generally, is the so-called tubular 

 dentine, the organic matrix being permeated by a series 

 of parallel tubes with fine branches which everywhere 

 penetrate it. 



This tubular dentine has been called by Tomes ' ortho- 

 dentine ' to distinguish it from other varieties which might 

 also be described as tubular. 



The classification of dentines adopted by Tomes is as 

 follows : 1 



Orthodentine. 



Plicidentine. 



Vasodentine. 



Osteodentine. 

 Rose, however, has suggested a different classification : 



f Vasodentine. 

 Orthodentme including | vitrodentine . 



Trabecular dentine. 

 Bone dentine. 



