THE NERVES OF THE TEETH. 



263 



rian ganglion. On the under surface of this ganglion is 

 seen the anterior root, having no connection with it and 

 being the motor portion. 



From the gasserian ganglion proceed three branches, 



1. The ophthalmic, 



2. The superior maxillary, 



3. The inferior maxillary nerve. 



FIG. 74. 



The two latter furnish the branches supplying the teeth. 

 The superior maxillary nerve 

 arises from the middle of the 

 ganglion of Gasser, passes 

 forwards through the fora- 

 men rotundum of the sphenoid 

 bone, into the pterygo-max- 

 illary fossa at this point it 

 sends off several branches, 

 two of which descend to join 

 the ganglion of Meckel. The 

 main trunk is continued for- 

 ward with the artery in the 

 infra orbital canal, as the in- 

 fra orbital nerve } and finally 

 emerges at the infra orbital 

 foramen between the levator 

 labii superioris alasque nasi, 

 and levator anguli oris muscles, anastomosing with the 

 nasal branch of the ophthalmic, and the portio-dura of 



FIG. 74 represents the distribution of the fifth pair, or Trifacial Nerve, and 

 especially those branches supplying the teeth. 



1 Orbit ; 2 Maxillary sinus, or antrum of Highmore ; 3 Tongue ; 4 Infe- 

 rior maxilla; 5 Root of fifth pair, forming the ganglion of Gasser; 6 Oph- 

 thalmic, or first branch of the fifth ; 7 Superior maxillary, or second branch 

 of the fifth ; 8 Inferior maxillary, or third branch of the fifth ; 9 Frontal 

 branch ; 10 Lachrymal branch; 11 Nasal branch, which latter, with 9 and 

 10, are branches again of the first or ophthalmic division of the fifth ; 12 

 Internal nasal nerve going through the anterior ethmoid foramen; 13 Ex- 

 ternal nerve ; 14 External and internal frontal nerve ; 15 Infra orbitar nerve ; 

 16 Posterior dental nerves; 17 Middle dental branch; 18 Anterior dental 



