This section is from the book "Dental Medicine. A Manual Of Dental Materia Medica And Therapeutics", by Ferdinand J. S. Gorgas. Also available from Amazon: Dental Medicine.
Remove loose clot, wash out cavity with hot water; then plug cavity with iodoform gauze; or, cotton dipped in mastic, and rolled in tannin; or, cotton saturated with oil of turpentine, or perchloride of iron; or, ferric alum; or, cotton saturated with phenol sodique, and then dipped in tannic acid; or, antipyrine on cotton. Internally: Administer three grains of tannic acid dissolved in two-thirds of a tumbler of water, of which two teaspoonfuls are given every five minutes until three doses have been taken, after which give the same quantity every fifteen minutes. Gallic acid, ergot, or oil of turpentine, may also be given internally, especially when the hemorrhage is indicative of some constitutional vice. In addition, upright posture, and a cool apartment.