DENTISTRY

The art or practice of a dentist. Directions for the extraction of teeth, as well as elaborate details for stopping them, and for the manufacture of artificial ones, are branches of the dentist’s art, which, as they nece itate the exercise of considerable skill and long practice, do not call for notice in a work like the present. We shall confine ourselves, therefore, to that section of dentistry which concerns itself with stoppings for the cavities of decayed teeth, and for the preparation of which we give the following formulæ:— 1. (Soubeiran’s.) Powdered mastic and sandarach, of each 4 dr.; dragon’s blood, 2 dr.; opium, 15 gr.; mix with sufficient rectified spirit to form a stiff paste. A solution of mastic, or of mastic and sandarach, in half the quantity of alcohol, is also used, applied with a little cotton or lint. 2. Sandarach, 12 parts; mastic, 6 parts; amber, in powder, 1 part; ether, 6 parts. Applied with cotton. Or simply a paste of powdered mastic and ether. Or a saturated ethereal solution of mastic, applied with cotton. 3. Taveare’s cement is made with mastic and burnt alum. Bernoth directs 20 parts of powdered mastic to be digested with 40 of ether, and enough powdered alum added to form a stiff paste. 4. Gutta perch a, softened by heat, is recommended. Dr Rollfs advises melting a piece of caoutchouc at the end of a wire, and introducing it while warm. 5. (Gauger’s Cement.) Put into a quart bottle 2 oz. of mastic and 3 oz. of absolute alcohol; apply a gentle heat by a water-bath. When di olved, add 9 oz. of dry balsam of tolu, and again heat gently. A piece of cotton dipped in this viscid solution becomes hard when introduced into the tooth, previously cleansed and dried as above. 6. (Mr Robinson’s.) After washing out the mouth with warm water containing a few grains of bicarbonate of soda, and cleaning the cavity as above directed, he drops into it a drop of collodion, to which a little morphia has been added, fills the cavity with asbestos and saturates with collodion, placing over all a pledget of blotting paper. 7. (Ostermaier’s Cement.) Mix 12 parts of dry phosphoric acid with 13 of pure and pulverised quicklime. It becomes moist in mixing, in which state it is introduced into the cavity of the tooth, where it quickly becomes hard. [In some hands this has failed, from what cause we are not aware.] The acid should be prepared as directed under Acid, Phosphoric . 8. (Silica.) This name has been given to a mixture of Paris plaster, levigated porcelain, iron filings, and dregs of tincture of mastic, ground together. 9. (Wirih’s Cement.) It is said to consist of a viscid alcoholic solution of resins, with powdered asbestos. 10. (Metallic Cement.) Amalgams for the teeth are made with gold or silver, and quicksilver, the exce of the latter being squeezed out, and the stiff amalgam used warm. Inferior kinds are made with quicksilver and tin, or zinc. A popular nostrum of this kind is said to consist of 40 gr. of quicksilver and 20 of fine zinc filings, mixed at the time of using. Mr Evans states that pure tin, with a small portion of cadmium, and sufficient quicksilver, forms the most lasting and least objectionable amalgam. The following is the formula:—Melt 2 parts of tin with 1 of cadmium, run it into ingots, and reduce it to filings. Form these into a fluid amalgam with mercury, and squeeze out the exce of mercury through leather. Work up the solid residue in the hand, and pre it into the tooth. Or, melt some beeswax in a pipkin over the fire, throw in 5 parts of cadmium, and, when melted, add 7 or 8 parts of tin in small pieces; pour the melted metals into an iron or wooden box, and shake them till cold, so as to obtain the alloy in a powder. This is mixed with 2 1 ⁄ 2 or 3 times its weight of quicksilver in the palm of the hand, and used as above. Another cement consists of about 73 parts of silver, 21 of tin, and 6 of zinc, amalgamated with quicksilver. An amalgam of copper is said to be sometimes used. But this cla of stoppings is altogether disapproved of by other authorities. Pure leaf-gold seems the least objectionable. 11. (Marmoratum.) Finely levigated gla , mixed with tin amalgam. 12. (Poudre Met all i que.) The article sold under this name in Paris appears to be an amalgam of silver, mercury, and ammonium, with an exce of mercury, which is pre ed out before using it. 13. (Fusible Metal.) Melt together 8 parts of bismuth, 5 of lead, 3 of tin, and 1 1 ⁄ 2 or 1·6 of quicksilver, with as little heat as po ible. (Chaudet.) 14. (Non-expensive Metallic Tooth-stopping.) Take 1 part of sulphate of mercury, 1 part of copper in fine powder; rub them well together with a little warm water; when the amalgam is formed wash well, and remove the surplus of mercury by pre ing it through chamois.— Pharm. Journ. Expensive Metallic Tooth-stopping and much preferable. Take pure gold, pure gelatin, 1 part of each; pure silver, 2 parts; melt, and when refrigerated, reduce to a powder by means of a file; wash well and dry. In the moment of using it add sufficient mercury to form a plastic paste.— Pharm. Journ. Paste for Destroying the Sensibility of the Dental Pulp previous to Stopping. Arsenious acid, 30 gr.; sulphate of morphia, 20 gr.; creasote, q. s. [Unsafe; it is only inserted by way of warning against what may prove an unsuspected cause of mischief.] Pivots for Artificial Teeth. An alloy of platinum and silver. Springs for Artificial Teeth. Equal parts of copper, silver, and palladium. (Chaudet.) For Cachou A rom at isé, and other compounds for sweetening the breath, see Perfumery .