180 



ANIMAL DENTISTRY. 



Definition — A congenital deformity in which the supe- 

 rior incisors overlap the inferior. 



Etiology — A congenital deformity of obscure cause. The 

 deformity consists of a deficiency in the proper length of the 

 inferior maxillary, or an abnormal elongation of the pre- 

 maxilla. 



Symptoms — Overlapping of the inferior incisor by the 

 superior ones vs^ith more or less elongation of the first supe- 

 rior and sixth inferior molars. The condition becomes more 



Fig. 127. 

 -"'*''''*"^ A Typical Case of Brachygnathism. -^^^^ 



and more aggravated with age. As the molars wear away 

 the inferior incisors reach the palate behind the superior in- 

 cisors. Nature, however, seems to meet the condition by 

 hardening of the palate and rounding the premaxilla so as to 

 accommodate the gradual transgression of the inferior in- 

 cisors. There will be difficulty in the prehension of attached 

 food, and the animal will be difficult to keep in good condi- 

 tion. 



Treatment — Parrot mouth is a defect for which horses 



