ANIMAL DENTISTRY. 



233 



contained in secretion coming from the lower air passages. 

 Treatment — The treatment includes: (i) Removal of 

 the primary lesion; (2) evacuation of the accumulated secre- 

 tions from the sinuses, and, (3) irrigation of the diseased 

 mucous membrane. Internal medication is of little value in 

 terminating nasal catarrh. Local applications in the form 

 of douches are equally useless. 



Fig. 151. 



Correct Locations of Openings to Perfectly Drain the Sinuses of a Horse's 

 Head. The upper opening drains the frontal sinus outward, and by per- 

 forating its floor in the turbinated bone, it also drains the sinus into the 

 nasal cavity. The dotted line on the lower opening shows the direction 

 to elongate the orifice when a tooth is to be repulsed. 



OPERATION OF TREPHINING THE SKULL FOR NASAL 



CATARRH. 



Equipment — ^Two scalpels, three-fourths inch circular tre- 

 phine, one inch circular trephine, dissecting forceps, chisel, 

 artery forcep, needles and thread (punches and mallet if 

 teeth are to be repulsed), razor, vi^adding of cotton or oakum 

 and antiseptics. 



