ERUPTION OF THE TEETH. 



ERUPTION OF THE INCISORS. 



The eruption of the deciduous incisors does not cause any 

 marked constitutional phenomena, although it may cause some 

 slight loss of appetite, — due, however, rather to the local pain in 

 chewing than to any general disturbance. With the appearance 

 of the permanent teeth the head increases in size and becomes 

 more full, which is due principally to the space demanded for 

 the large molars of second dentition. 



The appearance of the permanent teeth is a period of 

 general irritation of the animal economy. The first attack of 

 periodic ophthalmia frequently appears at this time ; colts seem 

 more susceptible to contract strangles and other of the contagious 

 diseases. 



Sometimes the temporary incisors drop out before the ap- 

 pearance of the permanent teeth ; in this case they leave a small 

 ulcer in the gum, which is followed by a swollen, red, sore 

 point, through which finally the replacing tooth appears by its 

 internal corner, Avhich is followed by the anterior border, set 

 not in its future proper position, but obliquely to the axis of the 

 jaw. When the temporary teeth have been pulled to hasten 

 the age, as is a growing custom in some of our neighboring- 

 markets, the obliquity remains, and when found in an apparent 

 five- or six-year-old mouth should always be regarded with sus- 

 picion. At other times the milk-teeth remain, and the permanent 

 ones protrude on their posterior border. Convulsions may occur 

 by excessive pressure and irritation in these cases. The incisors 

 of the upper jaw usually appear before those of the maxilla. 

 The pincher, intermediate, and corner teeth appear in succession 

 by pairs. 



Causes lohich can Hasten or Retard the Eraption of the 

 Incisors of the Second Dentition. — All ordinarv horses are 



' (43) 



