1 8 The Bones of the Head 



fossa and drilling upwards and inwards ; but if the first or sec 

 molar be decayed it may be extracted, and the cavity opened by passing 

 a gimlet up the emptied socket. 



Maligna?it disease often attacks the superior maxilla, and, entering 

 the antrum, grows at a great pace : advancing upwards, it raises, pushes 

 forward, and disorganises the eyeball; downwards, and it implicates the 

 palate and loosens the teeth ; inwards, and it blocks the nostril, and, 

 backwards, the pharynx. The only treatment likely to avail is exci- 

 sion of the superior maxilla. This operation is performed by making 

 an incision from the inner corner of the orbit down the side of the nose, 

 round the ala, traversing its cartilage, and through the middle of the 

 upper lip, the coronary artery being promptly secured. From the top 

 of the incision another is made horizontally outwards along the lower 

 margin of the orbit, and through the periosteum, which is then easily 

 raised from the floor of the orbit. The thick, irregular flap of the 

 cheek is turned outwards. The malar bone is then sawn across, and 

 the nasal process of the superior maxilla divided with bone nippers. 

 The central incisor having been previously extracted, the palate pro- 

 cesses of the palate and superior maxilla are nipped through, the soft 

 palate having been detached, and the loosened bone is then caught 

 with lion forceps and twisted out, the second division of the fifth nerve 

 and branches of the internal maxillary artery being torn across during 

 that procedure. 



The soft palate remains behind. So also may the periosteum of the 

 orbit, the latter structure playing a useful part in the subsequent sup- 

 port of the eyeball. Indeed, after some weeks, if all go well, the chasm 

 is so filled up by contractions that there is little to indicate that so 

 serious an operation has been performed, the eye-ball keeping its place. 



During the operation the following structures are divided', the 

 orbicularis oris, coronary artery, and labial mucous membrane ; lateral 

 nasal branches of the facial artery and vein, and branches of the infra- 

 orbital nerve passing to the nose ; the muscles which depress and dilate 

 the nostril. In raising the upper part of the flap the orbicularis palpe- 

 brarum, levator labii superioris, and levator anguli oris would be cut, 

 together with the infra-orbital nerve and artery, the angular branches of 

 the facial vessels, and branches of the facial nerve supplying the muscles. 

 The periosteum of the floor of the orbit and the origin of the inferior 

 oblique would be detached and raised. The more distant structures 

 detached are the buccinator ; the soft palate with the expansion from 

 the tensor palati ; the superior maxillary nerve in front of the fora- 

 men rotundum, and posterior palatine and dental branches of the 

 nternal maxillary artery. The muco-periosteum of the hard palate is, 

 of course, taken away with the bone. When the maxilhr arc narrow, 

 * V-shaped,' the palatine arch is contracted and the teeth appear in 

 great disorder. Not seldom, moreover, the deformity is associated 

 with mental deficiency. 



