

I 



THE TRIGEMINAL NERVE 895 



The Deep Temporal Nerves (nn. temporales profundi) are two in number, anterior 

 and posterior. They pass above the upper border of the Pterygoideus externus 

 and enter the deep surface of the Temporalis. The posterior branch, of small size, 

 is placed at the back of the temporal fossa, and sometimes arises in common with 

 the masseteric nerve. The anterior branch is frequently given off from the buccina- 

 tor nerve, and then turns upward over the upper head of the Pterygoideus externus. 

 Frequently a third or intermediate branch is present. 



The Buccinator Nerve (n. buccinatorus; long buccal nerve] passes forward between 

 the two heads of the Pterygoideus externus, and downward beneath or through 

 the lower part of the Temporalis; it emerges from under the anterior border of the 

 Masseter, ramifies on the surface of the Buccinator, and unites with the buccal 

 branches of the facial nerve. It supplies a branch to the Pterygoideus externus 

 during its passage through that muscle, and may give off the anterior deep temporal 

 nerve. The buccinator nerve supplies the skin over the Buccinator, and the mucous 

 membrane lining its inner surface. 



External Pterygoid Nerve (n. pterygoideus externus). The nerve to the Ptery- 

 goideus externus frequently arises in conjunction with the buccinator nerve, 

 but it may be given off separately from the anterior division of the mandibular 

 nerve. It enters the deep surface of the muscle. 



The posterior and larger division of the mandibular nerve is for the most part 

 sensory, but receives a few filaments from the motor root. It divides into auriculo- 

 temporal, lingual, and inferior alveolar nerves. 



The Auriculotemporal Nerve (n. auriculotemporalis) generally arises by two roots, 

 between which the middle meningeal artery ascends. It runs backward beneath 

 the Pterygoideus externus to the medial side of the neck of the mandible. It then 

 turns upward with the superficial temporal artery, between the auricula and con- 

 dyle of the mandible, under cover of the parotid gland; escaping from beneath 

 the gland, it ascends over the zygomatic arch, and divides into superficial temporal 

 branches. 



The branches of communication of the auriculotemporal nerve are with the facial 

 nerve and with the otic ganglion. The branches to the facial, usually two in number, 

 pass forward from behind the neck of the mandible and join the facial nerve at 

 the posterior border of the Masseter. The filaments to the otic ganglion are derived 

 from the roots of the auriculotemporal nerve close to their origin. 



Its branches of distribution are: 



Anterior auricular. Articular. 



Branches to the external acoustic meatus. Parotid. 



Superficial temporal. 



The anterior auricular branches (nn. auriculares anteriores) are usually two in 

 number; they supply the front of the upper part of the auricula, being distributed 

 principally to the skin covering the front of the helix and tragus. 



The branches to the external acoustic meatus (n. meatus auditorii externi), two in 

 number, enter the meatus between its bony and cartilaginous portions and supply 

 the skin lining it; the upper one sends a filament to the tympanic membrane. 



The articular branches consist of one or two twigs which enter the posterior part 

 of the temporomandibular joint. 



The parotid branches (rami parotidei) supply the parotid gland. 



The superficial temporal branches (rami temporales superficiales) accompany the 

 superficial temporal artery to the vertex of the skull; they supply the skin of the 

 temporal region and communicate with the facial and zygomaticotemporal nerves. 



The Lingual Nerve (n. lingualis) supplies the mucous membrane of the anterior 

 two-thirds of the tongue. It lies at first beneath the Pterygoideus externus, medial 

 to and in front of the inferior alveolar nerve, and is occasionally joined to this 



