THE DENTAL PULP 211 



were able to confirm Schweitzer's results by both methods, and 

 say, ' There is every evidence to support the correctness of 

 Schweitzer's statement that in the upper jaw the lymphatics 

 leaving the dental pulps course within the bony portion 

 of the maxilla and emerge through the infra-orbital and 

 other foramina into the subcutaneous tissue ; those of the 

 lower jaw enter the inferior dental canal, where they run 

 along with the blood-vessels and nerves, and thence pass 

 into the subcutaneous tissue. From either jaw lymph 

 vessels enter the sub maxillary and deep cervical glands.' 



The Nerves of the Pulp 



The nerves of the pulp and teeth are derived from the 

 fifth cranial nerve. The upper teeth are supplied by the 

 superior maxillary nerve, which arises from the Gasserian 

 ganglion, and the branches of this nerve which are distributed 

 to the teeth are the anterior, middle, and posterior superior 

 dental nerves. 



The posterior superior dental nerve arises from the trunk 

 of the superior maxillary nerve before it enters the infra - 

 orbital groove, and divides into two branches which enter 

 the posterior dental canal and supply the upper molar teeth 

 and the mucous membrane of the antrum, also contributing 

 small filaments to the mucous membrane of the gum and 

 cheek. 



The middle superior dental nerve arises at the back of the 

 orbital foramen, passes along a special canal in the anterior 

 wall of the antrum, and supplies the premolar teeth. 



The anterior superior dental nerve arises near the infra - 

 orbital foramen and is the largest branch of the superior 

 dental nerve. It traverses the canal in the front wall of the 

 antrum and supplies the canine and incisor teeth. It has 

 a nasal branch to the inferior meatus and to the floor of the 

 nasal fossae. 



The inferior maxillary nerve is the largest division of the 

 fifth nerve and consists of two portions, the larger one 

 arising from the Gasserian ganglion, and the smaller con- 

 sisting of the motor root of the fifth nerve, which unites with 

 the larger branch after passing through the foramen ovale 

 of the sphenoid bone. Beneath the external pterygoid 



p 2 



