SUBMAXILLARY REGION 279 



ganglion, and it unites with the lingual nerve a short distance 

 below the upper end of the latter. 



Dissection. The student should now endeavour, by means of a Hey's 

 saw, a chisel, and the bone forceps, to remove the outer table of the mandible, 

 and thus open up the mandibular canal. 



Structures within the Mandibular Canal. The mandibular 

 canal is traversed by the inferior alveolar vessels and nerve, 

 which give off twigs to the roots of the molar and praemolar 

 teeth. Both the artery and the nerve terminate by dividing 

 into a mental and incisor branch. 



The mental artery and nerve appear on the face through 

 the mental foramen, and have been examined already; the 

 incisor artery and nerve pass anteriorly to the symphysis and 

 send up twigs to the canine and incisor teeth. The vessel 

 anastomoses in the bone with the corresponding artery of 

 the opposite side. 



SUBMAXILLARY REGION. 



The superficial area of the submalallary region has been 

 dissected already, under the name of the anterior part of the 

 digastric triangle (p. 230). It is now necessary to carry the 

 dissection to a deeper plane, in order to expose a number 

 of parts in connection with the tongue and floor of the 

 mouth. The structures thus displayed are : 



1. Submaxillary gland and its duct. 



2. Sublingual gland. 



3. Side of the tongue, and the mucous membrane of the mouth. 



Mylo-hyoid. 



Digastric. 



Stylo-hyoid. 



Hyoglossus. 

 Stylo-glossus. 

 Genio-hyoid. 

 Genio-glossus. 



Mylo-hyoid. 



4. Muscles. 



Glosso-pharyngeal. 



6. Submaxillary ganglion. 



7. Lingual artery and veins. 



8. Part of the external maxillary artery. 



9. Stylo-hyoid ligament. 



Dissection. To prepare the part for dissection, it is necessary to throw 

 back the head to its full extent, and turn it slightly to the opposite side, 

 ii 18 c 



