VE TER1NAR T DENTAL S URGER }'. 131 



mere detachment from the lining of the primitive 

 groove by the formation of a fold in the lining 

 membrane and that in this cavity a papilla is formed 

 exactly in the same way as that of a temporary tooth. 

 Now I look upon the formations of these dental 

 tumors as being due to some eccentricity in this 

 folding of the lining membrane, by which the cavity 

 of reserve is made up of several folds; that these 

 folds become eventually separated from each other, 

 forming separate cavities of reserve; and that a 

 papilla becomes developed in each cavity thus 

 formed in a manner similar to those constituting the 

 papilla of the natural tooth. These irregular papilla? 

 become finally converted into irregular which for 

 want of space in the mouth are forced upwards into 

 the antrum (sinus), and may completely block it up 

 as well as the posterior opening. 



"I have classified them as cystic tumors, as, in the 

 first instance they are inclosed in sacs or cysts ; they 

 however, soon burst through their investing mem- 

 brane and form a large tumor, composed entirely of 

 teeth, having a great variety of shapes and running 

 in different directions. The teeth vary in size, some 

 being very small, others nearly as large as a perma- 

 nent molar. Each tooth has a pulp cavity, and is 

 composed of the same structures as the natural 

 teeth." 



