For local treatment, our first care should be to destroy the diseased surface in the interior of the mouth with a powerful caustic. Strong nitric acid is usually employed for this purpose. The acid should be applied once and effectually. The operation must be performed with care, so as not to touch the teeth, or any part which is not the actual seat of disease ; and immediately after the application the mouth should be well syringed with a solution of carbonate of soda or chloride of lime. Besides nitric acid, strong hydrochloric acid, the acid nitrate of mercury, nitrate of silver, and the strong solution of perchloride of iron have been used, and all have their advocates. Dr. J. Lewis Smith speaks highly of a combination of sul phate of copper ( 3 ij.) with pule. cinchona ( ss.), in four ounces of water. This application, which was originally recommended by Maunsell and Evan son, is milder than the others ; but applied carefully twice in the day it is said to have remarkable efficacy. If a stronger caustic is employed, a sec ond application should not be made within twenty-four hours of the first ; indeed, the operation should only be repeated if the further spread of the gangrene is unmistakable. The fcetor of the breath must be corrected by
frequent syringing with a disinfecting agent. A solution of chlorinated soda (Eq. soda chlorinate 3 j., aqua j.) is perhaps the most useful ; or one part of carbolic acid to ten parts of water, as recommended by Labar raque, may be employed for the same purpose.
The internal administration of quinine and iron seems to be beneficial in these cases, given in full doses. A child of three or four years old will take well two grains of quinine and twenty drops of perchloiide of iron, with glycerine and water, every six hours. After separation of the sloughs, any sign of repair should be encouraged by stimulating applications. A weak solution of sulphate of zinc (gr. iij. to the oz.), or any ordinary lotion for granulating wounds, may be used for this purpose.