NERVUS MAXILLARIS 



301 



upon the cut margin of the skull at a point immediately above 

 the external meatus, carry it obliquely downwards and forwards, 

 through the squamous part of the temporal bone and the great 

 wing of the sphenoid, towards the medial end of the superior 

 orbital fissure. This saw-cut should enter the superior orbital 

 fissure immediately to the lateral side of the foramen rotundum. 

 A second saw-cut should then be made from the cut margin of 

 the cranial wall, immediately above the anterior margin of the 

 great wing of the sphenoid bone, downwards into the superior 

 orbital fissure to meet the first saw-cut. The wedge-shaped 

 piece of bone included between the cuts can now be removed. 

 To obtain additional space, and to open up the pterygp-palatine 

 fossa more fully, remove what remains of the great wing of the 



Maxillary nerve 

 Ophthalmic nerve 

 ingeal branch of maxillary nerve - ' 

 Sensory root 



lotorroot ol v /-^~j 

 trigemina! // ^j7r~T 



Semilunar ganglion ' 

 Mandibular nerve 



Spheno-palatine ganglio 



Post, palatine '' 

 Middle palatine 



Ant. palatine 



Zygomatic nerve - Posterior superior alveolar 

 Infra-orbital 



Zygomatico-temporal 

 ] Zygomatico-facial 



Middle superior alveolai 



Anterior superior 

 r eolar 



FIG. 113. Diagram of the Maxillary Nerve. 



sphenoid upon the lateral side of the foramen rotundum, but 

 the circumference of that aperture must be carefully preserved. 

 Proceed, in the next place, to open up the infra-orbital canal. 

 In its posterior part its upper wall is usually so thin that it can 

 easily be removed by a pair of dissecting forceps, but more 

 anteriorly the canal sinks deeply under the lower part of the 

 rim of the orbital openingj and there the chisel must be employed. 

 The maxillary nerve can now be defined and its branches dis- 

 played. The infra-orbital artery and vein, which accompany 

 the nerve in the infra-orbital canal, will be exposed at the same 

 time. 



Nervus Maxillaris. The maxillary nerve springs from the 

 semilunar ganglion, within the cranial cavity (Fig. 113). It is 

 composed entirely of sensory fibres, and passes forwards, 

 outside the dura mater and in relation to the lower part of the 



