46 ON DENTAL EXOSTOSIS. 



white fibrous tissue, whilst others produce the firm 

 cartilaginous matrix in which the white fibrous 

 tissue is imbedded; with which it is ultimately 

 blended, and in which finally the ossific matter is 

 deposited. That this ossific matter is something 

 more than the calcareous salts which form an ingre- 

 dient in bone is, I think, proved by the fact, that 

 after their removal by means of dilute acid, instead 

 of obtaining again precisely the original tissue 

 which I have described, there remains behind a 

 matrix in which the appearances of this original 

 tissue are preserved, but it seems to have been 

 infiltrated with an ingredient which has rendered it 

 much denser and more compact. After the cessa- 

 tion of inflammation, and the subsequent change of 

 its products into cementum, fresh attacks being 

 excited from time to time, the deposit soon extends 

 far beyond the original layer of the dental perios- 

 teum ; but still all the requisite elements are formed, 

 as we have seen (viz., fibrous tissue and cartilaginous 

 matter), from effused plasma, and thus the morbid 

 growth increases to a surprising magnitude. In 

 stumps and carious teeth, the products of the inflam- 

 mation are converted at times into pus, and an 

 abscess is the result ; so that if a stump be drawn 

 when violent inflammation is present, we frequently 

 find, in addition to the histological elements already 

 mentioned, globules of pus on the outer surface of 

 mass of " coagulated lymph." That changes in 

 the alveolus should take place, must necessarily 



