A localised swelling of the mandible, associated with pain referred to the ear and neck, and in some cases with spasmodic contraction of the muscles of mastication, may be due to impaction of the wisdom tooth (lower third molar). If the tooth is merely embedded in the gum, incision may allow of its eruption; if the X-rays show that it is wedged under the second molar it must be extracted, and this may prove a difficult dental operation.
Affections of the Gums.—Inflammation of the gums—gingivitis—usually occurs in association with a general stomatitis. The gums are swollen and spongy, and may show superficial ulceration, associated with bleeding and extreme fœtor of the breath. The teeth become loose, project from the alveoli, and sometimes fall out. These symptoms are prominent in cases of scurvy, and of chronic mercurial poisoning. In chronic lead-poisoning a characteristic blue line is seen on the gums near the dental margin. The treatment consists in removing the cause, improving the hygienic and dietetic conditions of the patient, and administering lime-juice, iodide of potash, quinine, or cod-liver oil, according to the cause. Antiseptic mouth-washes and dentifrices are also indicated. Chlorate of potash, being excreted in the saliva, is particularly useful.
Pyorrhœa alveolaris is a chronic form of gingivitis, met with after middle life, which begins in relation to the necks of the teeth and the alveolo-dental periosteum. It is due to bacterial infection, and is associated with an accumulation of tartar between the gums and the teeth. A muco-purulent discharge escapes from within the free edge of the gum and alveolus. The alveolar borders and the gum subsequently undergo atrophy, so that the roots are exposed, and the teeth are liable to become loose and eventually to fall out. The condition may only affect a few teeth, or it may spread to them all, in which case the patient may in the course of some years become edentulous. Gastro-intestinal disturbances, chronic joint affections of the nature of arthritis deformans, a form of pernicious anæmia, and other general conditions have been attributed to the absorption of toxic products. The treatment consists in removing the tartar from the teeth, applying strong antiseptics to the groove between the teeth and the gums, and employing mouth-washes and dentifrices. Massage of the gums night and morning, and rubbing in a paste of chlorate of potash and menthol, is often of great value. Good results have followed the use of vaccines and improvement of the general health.
Hypertrophy of the gums is occasionally met with in children and young adults who are mentally defective, and the teeth appear early and are abnormally large. The gum almost buries the teeth, and large polypoid masses form which tend to fungate. The treatment consists in removing not only the hypertrophied gums, but also the affected alveolus (Heath).
A localised hypertrophy—polypus of the gum—sometimes results from the irritation of a carious tooth, or from the pressure of an artificial denture, and may simulate an epulis ([p. 513]). The swelling is usually pedunculated, and if cut away close to the alveolar margin does not tend to recur.
Epithelioma sometimes originates in the gum in relation to a carious tooth or to an artificial tooth-plate. The growth tends to invade the bone and to spread to the cheek or buccal mucous membrane, or to the maxillary antrum, and its malignant nature is suggested by its persisting after the removal of the irritation. The only treatment is early and complete removal of the growth and the adjacent segment of bone.
Other tumours of the gums, such as angioma and papilloma, are rare.
The Jaws
Pyogenic Infections.—The jaws may be infected in fractures communicating with the mouth or as a result of the unskilful extraction of teeth, but the majority of pyogenic infections originate in relation to carious teeth, beginning as a periodontitis which is followed by diffuse periostitis that may lead to necrosis of considerable portions of bone. In workers exposed to the fumes of yellow phosphorus, the bone may be so devitalised that it readily becomes infected with pyogenic organisms and undergoes a process of cario-necrosis—the phosphorus necrosis of the older writers.