354 ACTINOMYCOSIS OF THE JAW. 



Symptoms. A hard, firm swelling develops on the lower jaw, 

 which careful examination shows to be caused by an increase in the 

 volume of the bone. The swelling spreads and increases in size ; 

 and although it is at first only slightly painful, the animal soon shows 

 difficulty in chewing, masticating slowly, holding the head obliquely 

 on one side, and even allowing food to fall from the mouth. Closer 

 examination discloses the presence of purulent alveolar periostitis 

 of one or several molars, those, namely, at the point where the 

 swelling appears externally. The diseased teeth lie deeper in the 

 jaw than usual, or are pressed out of line. The masticated food 

 collected around them possesses a peculiarly penetrating and un- 

 pleasant smell, always noticed in alveolar periostitis of herbivora. 



Fig. 330 — Osteoporosis of the upper jaw Esser). 



The external skin increases in thickness, and gradually becomes 

 adherent to the swelling. Later, perforation takes place, and a 

 thick fluid yellow pus is discharged, in which actinomyces may be 

 found. A probe penetrates deeply into the bone and easily breaks 

 down its thin trabecule. Granulations form around the wounds, 

 and bleed readily when touched. As a rule, feeding is disturbed 

 and loss of condition sets in. 



Prognosis and course. The nature and position of the disease 

 make it evident that little can be done therapeutically. The ray 

 fungus possesses considerable powers of resistance, and when within 

 the bone, is exceedingly difficult to reach. The disease must almost 

 always be incurable, though Pilz and others claim to have had 

 recoveries after giving iodide of potassium internally, and applying 

 tincture of iodine locally. Nevertheless many unsuccessful cases have 

 been recorded. Moussu unhesitatingly states that potassium iodide 



