274 DISPLACEMENT OF THE TEETH. 



either partially or entirely escape wear, and thus become too long 

 and impede mastication. The nose, or even the entire head, may 

 be distorted, producing displacement of the teeth. This is termed 

 by Gurlt campylorhinus (Fig. 279). Leisering saw such a case 

 during life. Dose noted a peculiar abnormality in a cow. The 

 incisors stood in pairs, one behind the other. Although the animal 

 was three years old, no teeth had been shed. The under jaw was 

 deformed, and Gurlt considered this to be the real and primary cause 

 of the peculiarity. 



When slight, these changes are of little importance, but imme- 

 diately they become pronounced they produce various undesirable 

 results. The animal has difficulty in grazing, can no longer tear 

 off the short grass, and where the incisors are much affected masti- 

 cation even of cut food may prove difficult and painful. If the 

 molars fail to correspond, the grinding surfaces wear away unevenly, 

 and the overlapping part grows until it wounds the opposite 

 gum or even the palate, and thus produces pain in chewing. Devia- 

 tion of the axis of the tooth in either a backward or forward direction, 

 is continually aggravated by mastication, which tends still further 

 to thrust the tooth out of position and is apt finally to produce 

 alveolar periostitis. 



Schrader saw a horse in which the first left upper molar was 

 immediately behind the tush, while the second lay at the inner side 

 of the third, so that the first molar was separated from the others 

 by a space of 2 inches. The first two lower molars had grown into 

 this space and perforated the palate, and in drinking, the water 

 passed through this aperture and was discharged by the nostrils. 

 The horse, being much wasted, was slaughtered. 



Too great a space between the teeth is at once abnormal and 

 injurious, especially in the case of .the molars. The crowns of the 

 teeth should stand close together, so as to afford mutual support, 

 and prevent food entering the interspaces. Where intervals occur 

 food is driven into them, penetrates even the alveoli, producing 

 inflammation and loosening the teeth. Such alveolar periostitis is 

 very common in old animals. 



Treatment consists in shortening or removing the offending tooth. 

 In young animals too much of the tooth must not be removed at 

 once, as the pulp cavity may be exposed, and alveolar periostitis 

 set up. Where intervals occur between the teeth the evil is palliated 

 by giving soft food, so as to lessen the need for mastication, or by 

 extracting one or two teeth. 



