For use as a disinfectant, the form of carbolic acid which contains about ninety-four per cent. of the pure acid and known as "carbolic acid No. 4," is the best, and it may be used as an antiseptic in the following strength: for lotions or sponges, 2 1/2 per cent. in water; for spray or vapor, 5 per cent. in water; for a dressing, 5 per cent. in olive oil. Carbolate of potash (unofficial - Robinson's remedy) is composed of equal parts of carbolic acid and caustic potassa rubbed together; it is employed in pyorrhoea alveolaris and hyper-sensitive dentine. Carbolic acid one-third and potassa fusa two-thirds is escharotic, anaesthetic, obtundent and disinfectant; such a combination causes a definite slough, and is useful in suppurating surfaces, sloughing ulcers and dead tissue.

Synthetic Carbolic Acid

Hitherto all carbolic acid used in medicine has been prepared from coal-tar. But such an acid is never quite pure, always containing impurities derived from the coal-tar. Synthetic carbolic acid is produced during the process of sulphonizing benzol and subsequent fusion of the benzol-sulphonate with caustic alkali. The most characteristic difference between it and the acid prepared from coal-tar is the odor, the synthetic acid having a faint "pure" odor not like that of coal-tar, and almost unperceivable in a 5 per cent. aqueous solution, differing in this respect also from the commercial article. Synthetic carbolic acid is in two forms - in a coherent crystalline mass, and in loose crystals. Experiments made by Dr. Ohlmueller, of the German Health Department, showed that the synthetic acid diminished the life activity of the bacteria experimented on rather less than the older acid, but that the difference was so small that the two kinds might be considered to be practically of the same value. One of the advantages claimed for synthetic carbolic acid is its greater solubility in water, thus enabling the operator to use it in greater strength without diminishing its causticity.

Phenol Sodique (unofficial) is a solution of sodium carbolate, and is extensively employed in dental practice. (See Phenate of Soda.) It is composed of pure melted carbolic acid, 5 parts; solution of caustic soda (of a specific gravity of 1.332), 1 part; distilled water, 5 parts. Mix.

Carbolate of Camphor is composed of carbolic acid, by weight, one part, and camphor, by weight, three parts.

Dental Formulae

A Lotion for Soft and Spongy Gums.

Acidi carbolici . . . gr. xx Spiriti rectificati (alcohol.) ......3 ij.

Aquae destillatae . . ^vj. M. It renders the gum less tender and firmer.

An Antiseptic Lotion or Injection.

Acidi carbolici . . .

Glycerini.....

For alveolar abscess and ulcers of mouth. The glycerine modifies the caustic action of the acid.

A Stimulant and Antiseptic Lotion.

Dr. J. Stocken.

Acidi carbolici . . .

Glycerini.....

Aquae.......

Useful in ulceration of the gums and mucous membrane.

For Sensitive Dentine and Alveolar Pyorrhoea.

Dr. J. A. Robinson.

Acidi carbolici . . . (cryst.) Potassse caustic . aa partes equal. Misce, by triturating in a mortar until a crystalline paste is formed. SlGna. - Apply on a loosely rolled twist of cotton about neck of tooth, for alveolar pyorrhoea. It is known as the " Robinson Remedy."

For Alveolar Pyorrhoea (Riggs' Disease).

Acidi carbolici . . .

Potassas iodidi . . . gr.v

Zinci chloridi . . . gr.xxv

Alcohol absolut . . .

Aq. destillatae . . .

01. menthae pip. . .

Misce et filtra.

Signa

As an injection in pus-pockets of gum.

A Disinfectant Mouth Wash.

Dr. J. B. Patrick.

Acidi carbolici (cryst.), Glycerini,

Aquae rosae .... . aa Signa. - Five to eight drops in a wineglass of water.

A Stimulant and Antiseptic Mouth Wash.

Acidi carbolici . . . gtt.xx

Glycerini.....

Aqua;.......

Signa

To be used as a gargle.

For Fetid Perspiration.

Acidi carbolici ... 2 parts Glycerini.....3 parts M.

For Parasitic Skin Diseases.

Acidi carbolici . . . Glycerini.....

Antiseptic Solution for Washing and Spraying Wounds, etc.

Acidi carbolici (cryst.) partem j

Aquae.......part. xxiv.

Signa

Dilute the above solution with equal parts of water, which will make it equal to 1 part of the acid to 40 parts of water; also for use in disinfecting instruments and sponges.

For Dry Mouth.

H. J. Fish.