DISSECTION OP THE HEAD AND NECK. 219 



The Anterior Deep Temporal Artery passes forwards out of the 

 subsphenoidal canal by the temporal foramen above the edge of the 

 orbital hiatus. It is expended in the temporal muscle and the over- 

 lying skin. 



The Buccal Artert is detached shortly after the parent vessel 

 emerges from the bone. It has already been followed in its distribution 

 to the cheek. 



The Superior Dental Artery is a large branch which enters the 

 superior dental canal. The vessel is continued above the roots of the 

 molar, incisor, and canine teeth. Before passing into the canal, it 

 gives off an orbital branch which passes across the floor of the orbit to 

 reach the face. Within the canal it emits an infraorhital branch which 

 reaches the face by the infraorbital foramen. 



The Staphylinb Artery is a slender branch given off from the 

 posterior aspect of the internal maxillary, close to the maxillary hiatus. 

 It courses along the staphyline groove to reach the soft palate. 



The Spheno-palatinb (Nasal) Artery. This vessel is of considerable 

 size, and passes at once through the spheno-palatine foramen to be dis- 

 tributed in the nasal chamber. 



The Palato-labial Artery is the continuation of the internal maxil- 

 lary. It passes along the palatine canal to reach the hard palate. 



Veins. At this point the veins have a disposition slightly different 

 from the arteries. The alveolar vein — a large vessel lying on the 

 superior maxilla in front of the molar teeth — turns round the bone and 

 reaches the maxillary hiatus. Here it receives superior dental, palatine, 

 and spheno-palatine branches. It then perforates the ocular sheath 

 within which it joins the ophthalmic, vein. The opthalmic vein passes 

 into the cranial cavity by the foramen lacerum orbitale, and joins the 

 cavernous sinus. 



The superior dental and spheno-palatine veins emerge by the same 

 foramina as the corresponding arteries. The palatine vein, however, 

 does not issue from the palatine canal, but turns round the bone in the 

 staphyline groove. 



The Superior Maxillary Division of the 5th Nerve. This sensory 

 division of the trifacial emerges from the cranium by the foramen 

 rotundum, as a large round cord. In company with the internal maxil- 

 lary artery, it descends to the maxillary hiatus, where it enters the 

 superior dental canal. Within the canal it gives dental branches to the 

 roots of the molar, canine, and incisor teeth, and then issues on the face 

 at the inffaorbital- foramen. In its passage between the orbital and the 

 maxillary hiatus, it gives off the following branches: — 



1. An Orbital Branch. — See page 217. 



2. The Palatine Nerve accompanies the palato-labial artery into the 

 palatine canal, and is distributed to the hard palate. 



