SYMPTOMS OF ALVEOLAR PERIOSTITIS. 
45 
Many cases remain confined to the alveolus. When an upper molar 
is completely loosened it may fall out; lower molars are not so readily 
displaced, though they may be equally loose; for this reason, the loose 
molars which can be extracted with the hand are usually found in the 
lower jaw. Sometimes inflammation seizes on the thin plate of bone 
which forms the alveolus and extends to the medulla. Purulent osteo¬ 
myelitis thus results. This irritates the periosteum of the outer surface 
of the bone, and produces periostitis ossificans, which causes the bone 
to swell. Finally the pus breaks through the bone, and a dental fistula 
results. After discharge of the pus, granulations form, and the point 
of perforation heals up, until only a narrow channel remains com¬ 
municating with the root of the tooth. This persists (compare “ dental 
p IG< —Necrosis of a dental alveolus, with dislocation of the last molar and 
extensive periostitis of the lower jaw (horse). 
fistula ”). In disease of the upper molars, the pus sometimes breaks into 
the superior maxillary sinus. Perforation into the nasal cavity may 
follow disease of the pre-molars and produce a chionic nasal dischaige. 
Occasionally the alveolar wall becomes necrotic, and extensive peiiostitis 
ensues. Fig. 19 shows how much a tooth may be displaced. The last 
molar lay horizontally, and under it a piece of bone the size of a hen s 
egg had become necrotic. 
The symptoms consist in slow, interrupted, one-sided mastication, lolling 
of the tongue, slobbering, and dropping food from the mouth. Even from 
the outside it may be discovered that one or other of the teeth is dis¬ 
placed ; while the buccal pouches are distended with masses of food. On 
passing the hand into the mouth, the exact displacement is ascertained. 
The peculiar, repulsive so-called “carious” smell, especially noticeable 
in the retained masses of food, is quite characteristic of alveolar peri¬ 
ostitis. In dogs the smell, whilst very offensive, is somewhat different to 
