220 
ON DISEASES OF THE DENTAL APPARATUS 
is suspended, and pus assembles in the interior of the alveolar 
cavity around the root, which then ceases to augment in volume. 
Whatever may be the manner of alteration and deformity of the 
tooth under the influence of caries, it is rare that the bone upon 
which it is implanted does not itself become the seat of a patholo- 
gical state, variable in gravity and extent, according to the inten- 
sity and duration of the cause which determines it. 
It is also necessary to take into consideration the position of the 
diseased tooth in order to appreciate the extent of the lesions which 
a simple caries can determine in the bones of the head and in the 
cavities which these bones assist in forming. The caries of the teeth, 
of which the roots are immediately subjacent to the sinuses, is 
often complicated with alterations exceedingly grave in the interior 
of these cavities. 
In the inferior maxilla they may be complicated with lesions of 
the bones identical for all the alveoles, whatever may be the posi- 
tion of the diseased teeth, since the organization of the bone is the 
same in its entire extent. 
When a tooth is carious, and its root is become the seat of an 
exostosis by the augmented secretion of the alveolo-dental mem- 
brane, it determines, we have said, a forced separation of the pari- 
etes of the alveolar cavity ; the osseous tissue, violently distended 
by this constant effort, tumefies, and becomes excessively painful : 
then, the action of the cause continuing, suppuration establishes 
itself in the interior of the alveole ; the membrane which lines it 
is destroyed in part, and leaves the bone naked, exposed, without 
shelter, to the maceration of pus, and to the irritating contact of 
the altered matters which continually penetrate into the alveole by 
the dental fistula. In these conditions the bony tissue sphace- 
lates upon the borders, where its substance is the most compact; 
and its spongy tissue, which forms the depth of the cavity, soon 
becomes the seat of an interstitial suppuration, that is to say, in 
fact, of veritable caries. It is then that the swelling may extend 
throughout the entire extent of the maxillary branch, and that 
mastication is decidedly rendered impossible. 
It can now be foreseen, an alteration of this nature being set in 
action, how the phenomena of the nutrition of the bone may be 
modified in their direction to the point of producing osteo-sarcoma. 
Such is the march of lesions, which a persistent caries can deter- 
mine in tissue of the inferior maxilla. 
In the superior jaw, the phenomena are in principle the same; 
that is to say, the tissue of the bone mortifies and becomes cari- 
ous in the same manner, under the influence of a forced disten- 
tion of the tables of the alveoles and the suppuration which 
