PRACTICAL CONSIDERATIONS: THE MOUTH. 1595 



the coating and of the tongue itself varies greatly, but it may be said that dry- 

 ness not due to mouth-breathing, but from deiicient secretion, as in fevers ; dark- 

 ness, from decomposition and desiccation of the coating, or from imperfect oxy- 

 genation of the blood ; roughness, from papillary overgrowth with marked epithelial 

 proliferation and desquamation ; redness, from epithelial denudation ; and stiff- 

 7iess, slowness, or tremulousness in protrusion, from either thick, inflexible coating, 

 muscular weakness, or mental hebetude, are uniformly regarded as unfavorable 

 conditions. 



Unilateral furring of the tongue has been observed in cases of dental caries, of 

 fractured skull, and of intracranial disease, in all three instances the furring being on 

 the side on which there was irritation of the branches of the fifth pair of nerves. In 

 some of them it was confined to the anterior two-thirds of the upper surface, — i.e. , 

 to the distribution of the lingual branch of the fifth (Hilton). 



In tonsillitis the tongue will often be furred over its posterior part only — 

 i.e., the portion which, like the tonsil, receives its nerve-supply from the glosso- 

 pharyngeal (Jacobson). Unilateral furring in the presence of toothache may be due 

 partly to the instinctive immobilizing of that side of the tongue nearest the painful 

 tooth (Hutchinson). 



In chronic superficial glossitis the epithelium thickens at places into rounded, 

 whitish patches, which are difilicult to heal on account of the constant exposure 

 to warmth, moisture, infection, and minor traumatisms, and the impossibility of 

 securing rest. This condition (^leukoplakia) may precede the development of 

 epithelioma. 



In rare cases the epidermis covering the filiform papillae undergoes hypertrophy, 

 producing the so-called " hairy tongue." 



The lymphoid tissue behind the circumvallate papillae, from overgrowth, forms 

 an irregular rounded mass just beneath the mucous membrane, — the lingual tonsil, 

 — which from its proximity to and interference with the epiglottis may require 

 removal. 



The connective tissue of the tongue is scanty, but is abundant enough to permit 

 of great swelling in cases of acute glossitis, and this is favored by the vascularity of 

 the organ. The cause is always infection through a surface solution of continuity 

 either traumatic or during some disease attended by drying and fissuring of the 

 tongue. On account of the vascularity, naevoid growths are frequent. 



Carcino7na of the tongue is exceedingly common, and Treves calls attention to 

 the fact that it usually affects the anterior two-thirds or that portion which is derived 

 from the mandibular arch, as is the lower lip, which is also one of the commonest 

 sites of epithelioma. Cancer of the fore part of the tongue may follow the lym- 

 phatics of that region into the submaxillary glands, or pass by the main lymphatic 

 channels into the deep cervical glands. Those first demonstrably enlarged, what- 

 ever the site of the cancer, are apt to be in the group beneath and behind the angle 

 of the jaw. 



The pain in cancer of the tongue is almost always associated with what are 

 described as ' ' earache, " " toothache, " " faceache, ' ' and sometimes with spasm of 

 the muscles of mastication. These symptoms are due to the connection of the 

 lingual branch of the fifth pair with other branches of the third division of the fifth, 

 especially the auriculo-temporal and inferior dental, with the tympanic branch of the 

 glosso-pharyngeal, and with the chorda tympani from the facial. 



Pressure upon, or disease of, the hypoglossal nerve may cause unilateral atrophy 

 of the tongue. The various paralyses should be studied in connection with the 

 nervous supply of the tongue. 



As the tongue depends upon muscular and not ligamentous attachments for the 

 preservation of its position in the mouth, its tendency to drop backward by gravity 

 during complete anaesthesia or some other forms of profound unconsciousness in 

 which muscular relaxation or paralysis occurs should not be forgotten. If it is 

 allowed to fall back, the pressure on the epiglottis may close the opening into the 

 larynx. During anaesthetization it is well to press the lower jaw well forward, carry- 

 ing the tongue with it through the attachments of the genio-glossi, and to elevate the 

 chin, which still farther advances the tongue and removes it from close proximity to 



