36 ANATOMY AND PHYSIOLOGY 



The incisors are the front teeth, four in number in each jaw. 

 They are used for biting and cutting the food. 



The cuspids (pointed) or canine teeth are situated next to the 

 incisors; they also bite and masticate. 



The bicuspids (two-pointed) or pre-molars, and the molars are 

 for purposes of mastication. 



The shapes of all are shown in the illustrations. 



The teeth are hollow and contain tooth-pulp. This consists of 

 a delicate meshwork of vessels and nerves entering at the point of 

 the root, wrapped in connective tissue and filling the pulp cavity. 



The upper teeth are imbedded in the alveolus of the maxilla, or 

 upper jaw; the lower teeth in the alveolus of the mandible, or lower 

 jaw. 



Dentition : the Eruption of the Teeth 



The teeth make their appearance in two sets, called temporary 

 and permanent. 



FIG. 29. THE TEMPORARY TEETH. 

 The rudiments of the permanent teeth are seen enclosed in the bones. (Gorgas.) 



The temporary teeth are twenty in number; their eruption or 

 " cutting " usually begins at about the seventh month and proceeds 

 in following order: 



Two lower central incisors at 7 months. 



Two upper central incisors at 8 to 10 months. 



Two upper lateral incisors at 9 to 12 months. 



