no SURGICAL APPLIED ANATOMY. [Chap. vu. 



eight years, with the breech and screw of a burst 

 musket lodged in the nares, part of the tail-pin and 

 screw protruding through the hard palate into the 

 mouth." The bone may undergo extensive necrosis, 

 especially in that form of necrosis induced in workers 

 in match factories by exposure to the fumes of phos- 

 phorus. In one case (Med. Times, 1862) of necrosis 

 following measles the mischief was limited to the pre- 

 maxillary, or incisive bone. 



The periosteum of the superior maxilla is, like the 

 pericranium, not disposed to form new bone. In 

 ordinary cases of necrosis of the upper jaw no repro- 

 duction of bone takes place, the gap. left being perma- 

 nent. In the lower jaw abundant new bone is produced 

 by the periosteum, and extensive losses maybe repaired. 

 It is vemarkable, however, that in course of years this 

 new bone is liable to be very extensively reabsorbed. 



Excision of the superior maxilla, The 

 entire bone has been frequently removed when the 

 seat of an extensive tumour, and under certain other 

 conditions. The bony connections to be divided in the 

 operation are the following: (1) The connection with 

 the malar bone at the outer side of the orbit ; (2) the 

 connection of the nasal process with the frontal, nasal, 

 and lachrymal bones ; (3) the connections of the orbital 

 plate with the ethmoid and palate (this plate is often 

 left behind, or is cut through near the orbital margin) ; 

 (4) the connection with the opposite bone and the 

 palate in the roof of the mouth ; and (5) the connection 

 behind with the palate bone, and the fibrous attach- 

 ments to the pterygoid processes. In the four first- 

 named instances the separation is effected by a cutting 

 instrument ; in the last-named, by simply twisting out 

 the bone. Soft parts divided : These may be con- 

 sidered under three heads : (1) The parts cut in the first 

 incision ; (2) in turning back the flap ; and (3) in sepa- 

 rating the bone. 



