Chap, vii.j THE PAROTID REGION. 87 



orifice of the dental canal. The nerve is here picked 

 up with a hook, isolated, and divided. 



The buccal nerve may be the seat of severe neu- 

 ralgia, and may be thus divided through the mouth : 

 " The surgeon places the finger-nail upon the outer lip 

 of the anterior border of the ascending ramus of the 

 lower jaw at its centre, and divides in front of this 

 border the mucous membrane and the fibres of the 

 buccinator vertically. He then seeks for the nerve, 

 separating the tissues with a director, and divides it " 

 (Stimson). 



The malar bone. Such is the firmness of this 

 bone, and so direct is its connection with the skull, 

 that violent blows upon it are very apt to be associated 

 with concussion. Resting as it does upon com- 

 paratively slender bones, it is very rare for the malar 

 bone to be broken alone. It may, indeed, be driven 

 into the superior maxillary bone, fracturing that 

 structure extensively, without being itself in any way 

 damaged. A fracture of the malar bone may lead to 

 an orbital ecchymosis, precisely like that which often 

 attends a fracture of the skull base. 



2. The parotid region. The main part of the 

 parotid gland is lodged in a definite space behind the 

 ramus of the lower jaw. This space is increased in 

 size when the head is extended, and when the inferior 

 maxilla is moved forwards, as in protruding the chin. In 

 the latter movement, the increase in the antero-posterior 

 direction is equal to about three-eighths of an inch. 

 It is diminished when the head is flexed. When the 

 mouth is widely opened the space is diminished below, 

 while it is increased above by the gliding forwards of 

 the condyle. These facts should be borne in mind 

 in operating upon and in exploring the parotid space. 

 It will be found also that in inflammation of the 

 parotid much pain is produced by all those move- 

 ments that tend to narrow the space occupied by the 



