Chap, vii.] THE UPPER JAW. 93 



direction and degree of the force employed, no 

 muscles having effect. The bone being very vascular, 

 serious injuries, involving great loss of substance, are 

 often wonderfully repaired. Its hollowness, and the 

 cavities that it helps to bound, render it possible 

 for large foreign bodies to be retained in the 

 deeper parts of the face. Thus, Longmore reports 

 " the case of Lieutenant Fretz, of the Ceylon Rifles, 

 who was able to do his military duties for nearly 

 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 in- 

 duced in workers in match-factories by exposure 

 to the fumes of phosphorus. In one case (Med. 

 Times, 1862) of necrosis following measles the 

 mischief was limited to the premaxillary, or incisive 

 bone. 



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 attachments 

 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) Tho parts cut in the first 



