222 



HUMAN ANATOMY. 



The eruption of permanent teeth takes place in years as in 

 Fig. 52, the order of the eruptions being, first the "first or 

 sixth year molar," followed by the first central incisors, four 

 lateral incisors, four first bicuspids, four second bicuspids, the 

 first canines or cuspids, the four second molars, and ending with 

 the four third molars or "wisdom teeth." 



About the sixth year the jaws contain the temporary teeth 

 fully erupted, and the crowns of all the permanent teeth except- 

 ing the four wisdom teeth, in all forty-eight. 



It should be noted that the first permanent or "sixth-year" 

 molar is erupted before any of the permanent teeth, and that the 

 second bicuspid takes the place of the second temporary molar. 



M. 



12-16 



Wi. 



16-20 



FIG. 114. PERMANENT TEETH. 



Vessels and Nerves of the Teeth. The arteries of the upper 

 teeth are derived from the anterior dental branches of infra- 

 orbital and posterior or alveolar dental branches of the internal 

 maxillary; of the lower teeth, from the inferior dental branch 

 of the internal maxillary. 



The nerves are distributed to the upper teeth from the an- 

 terior and posterior dental branches of the superior maxillary 

 (second division of fifth cranial nerve), and to the lower teeth 

 from the inferior maxillary (third division of fifth cranial 

 nerve). 



Soft palate is a movable fold of mucous membrane sus- 

 pended from the posterior border of the hard palate, and inclos- 

 ing an aponeurosis, vessels, nerves, glands, and the following 



