the writer has suggested an aseptic medicament tray, as shown in Fig. 3. The elongated depressions in the tray are filled with a mixture of four parts of alcohol and one part of glycerin, in which broaches, root-canal cleansers, etc., may be kept immersed while working on the tooth. It must be borne in mind, however, that the mechanical removal of the débris of a decomposed pulp from a rootcanal forms the most important procedure in its routine treatment. It is a gross fallacy to assume that neglect in this respect can be counterbalanced by the future use of antiseptics. To depend upon a chemical agent to perform that portion of the work which should be done by mechanical means, is a misinterpretation of the bactericidal action of antiseptics. At best, antiseptics are only accessories to, and not substitutes for, efficient mechanical procedures. In conformity with the laws governing the action of antiseptics it must be repeated that the antiseptic power of germicidal solutions is practically restricted to that portion of the root-canal with which they actually are brought in contact-at best a very superficial process-and no antiseptic seems to possess any considerable power of penetration without simultaneously losing its activity. It should be an invariable rule with the operator to enter a root-canal only with absolutely sterile broaches, absorbent-paper or cotton points, etc. A convenient and simple sterilizer for absorbent points and gutta-percha points. has been recently devised by the writer: A screw-cap bottle of about one ounce capacity is provided with a piece of thick cotton roll of about one inch in length (Fig. 4), which is fastened to the interior of the cap with sealing-wax. About five drops of dichloramin-T solution are placed upon the lower end of the roll, where they are quickly absorbed. The chlorin compound is renewed about once a month. The paper, cotton, or gutta-percha points are placed in the bottom of the dry bottle, the screw cap is put into position and the permanent sterilizer is completed. The efficiency of this simple device has been repeatedly tested by plating out the points; they have always been found to be absolutely sterile. The chemical treatment of the infected root-canal, and incidentally its enlargement when obstructed, should invariably immediately follow as the second stage in the routine sequence. Schreier, in 1893, advocated an alloy of potassium and sodium (kalium-natrium) for such purposes, and the late Dr. John R. Callahan, in the same year, introduced the use of 50 per cent. sulfuric acid. The sulfuric acid method enjoys at present a wide popularity, although other acids, i.e. 10 per cent. hydrochloric acid, pure nitro-hydrochloric acid (aqua regia), and phenol-sulfonic acid have been recommended. The therapeutic absurdity of the latter compound has been dealt with by the writer on a former occasion.* Pure nitro-hydrochloric acid, as introduced by G. W. Weld in 1897, is the most efficient agent for the above purposes. On account of its strong caustic properties, extreme care is required in handling it. This acid should be preserved in glass-stoppered bottles and preferably kept outside of the operating * See DENTAL COSMOS for April 1912, page 397. room, as its fumes are most destructive to metallic instruments. It may be applied by means of a steel broach. Concentrated aqua regia has practically very little effect on steel, as the broach is at once covered by a protective oxid by the action of the evolved nitrosyl chlorid, which checks the further action of the acid upon the metal. This Whatever acid is employed should be neutralized by sodium dioxid, as recommended by Kirk in 1894, and not by sodium bicarbonate, which is practically useless for the above purposes. agent is carried into the root-canal by means of a broach previously dipped into chloroform; the latter substance merely acts as an indifferent conveyer of the sodium dioxid to the root-canal, which, if water or ordinary alcohol is used, readily decomposes. The chemical interchange between the various acids may be portrayed by their respective reactions. as follows: H2O2+ 2HCl = 2H2O + Cl2 The evolution of nascent oxygen which follows as a sequence of the reaction between the sodium dioxid and any of the acids employed is an important factor in the chemical treatment of the rootcanal, as it will materially assist in the preservation of the natural color of the tooth. Copious washing of the canal. with water should be followed by the removal of moisture. Sterile paper points assisted by a few drops of acetone, hot air, or a heated silver wire are serviceable for this purpose. Overheating of the tooth must be carefully avoided; however, a fair dryness of the root-canal must be insisted upon, as otherwise the future treatment with dichloramin-T is materially impaired. A suitable paper point is now saturated with dichloramin-T, carried to the root-canal, and with a pumping motion an attempt is made to coat the walls of the latter, and if possible a droplet is forced into the peri apical space. The use of the warm air blast is of material assistance in getting the oily solution into the finer ramifications of the canal. The warm air blast is recommended in this connection solely for its mechanical effect in aiding the diffusion of the dichloramin-T throughout the dentin, but its use as a means for previous desiccation of the canal walls is not admissible, for the reason that the natural moisture of the tooth structure is necessary to the production of nascent chlorin resulting from the reaction of the dichloramin-T with the water of the organic structure of the tooth. A fresh point carrying a drop of the chlorin solution is now slowly forced into the canal to its very end and immediately sealed with a suitable retainer. As we have stated above, close contact of the antiseptic solution with the walls of the root-canal, and if possible, with the surface of the involved infected area within the periapical tissues, is essential to obtain therapeutic results. The first application remains undisturbed for twenty-four hours. At the return of the patient the point is removed aseptically and carefully examined, and if found discolored a second acid treatment is necessary. The second dichloramin-T treatment placed in the dry canal, again remains twenty-four hours, while a third application is usually left in position for forty-eight hours. The paper cone removed at the last sitting must show no discoloration, it must have a distinct odor of chlorin, and it must be fairly free from absorbed exudates. Under no consideration should a first or second treatment be left in the canal over twenty-four hours; at the end of this time the chlorin compound is completely exhausted, and usually a pronounced flow of lymph, as referred to above, is the sequence. If at the last treatment the canal is found satisfactorily clean, no time should be lost in filling it at once. In all cases in which the infection from the root-canal has passed into the periapical space, localized pathological disturbances arise which may lead to the formation of an alveolar abscess. The content of the abscess cavity is usually forced to the surface along the lines of least resistance, i.e. either through the root-canal or through the bony wall of the alveolus and thereby establishing a fistula. In either case the treatment does not differ from the above-discussed principles. be insisted upon as the crucial test of therapeutic evidence of any new remedy. In the discussion of the clinical efficiency of a drug, the post hoc ergo propter hoc type of logic is only too apt to creep in, which naturally leads to a biased reasoning. The raw material of science consists of unconformable facts, hence the logic of Aristotle, which ignores this evidence, must be forsaken in an inquiry into the efficiency of a therapeutic agent. On a former occasion, regarding the methods of research, we have stated that In cases in which a fistula exists, an effort is made to establish a communication between the root-canal and the fistula proper by forcing normal saline solution through the fistula via the rootcanal. Dichloramin-T solution is now pumped through the root-canal into the fistula until it appears at its orifice. In from twenty-four to forty-eight hours after the first treatment the external opening will usually be found closed. The treatment of a granuloma, i.e. the product of a chronic proliferating peri- servations, and are explained. cementitis, does not differ from the routine procedure. It should be understood, however, that the dichloramin-T solution must actually pass through the foramen into the periapical space so as to be brought into close contact with the walls of the granuloma. In investigation into a remedy, or, for that matter, any biologic problem, the following four rules of research must be observed: THERAPEUTIC EVIDENCE. Regarding the existing sterility of a primarily infected root-canal as treated by the above-outlined dichloramin-T method, it should be emphasized that rigorous bacteriological tests were made in numerous instances by plating out scrapings from the walls of the canals. before and after they had been pronounced clinically ready to fill. These tests consisted in subjecting the scrapings to incubation upon agar plates, bouillon, etc. After exposure in an incubator for various lengths of time, usually from forty-eight to seventy-two hours, it was observed in all instances that the growths from these scrapings of the treated canals were negative, i.e. no cultures were obtained. "The day of authority in any branch of science has gone by;-statistics on the table, please." This eminently logical dictum of Prof. Karl Pearson portrays a sound scientific doctrine, and it should (1) Generally known observations or facts are collected. (2) Hypotheses are drawn from these ob (3) Other crucial facts (experiments) are collected to test these hypotheses, and (4) A second set of facts is collected, and from it are drawn the final conclusions or verifications: Omitting one of these rules or applying illogical reasoning based on analogy, or inductive instead of deductive methods, leads to a false analysis of the problem under consideration. The final proof of therapeutic efficiency rests upon the application of the remedy to the patient in conformity with the good old truism, "The proof of the pudding is in the eating." However, the real problem is by no means fully substantiated by clinical evidence only; a causative connection between the remedy and the event has to be established. The question now arises, What proofs have we in regard to the therapeutic efficiency of dichloramin-T in the treatment of infected root-canals? (1) General known observations. Up to the present (October 1918) Dr. Lee and his co-workers announce that "Records have been obtained from 19,040 completed cases in civil surgical practice which have been treated with this agent, and Captain Sweet, U.S.A., base hospital No. 10, France, in July 1917 obtained the records of a total of 4903 cases treated with the preparation." (2) Hypotheses drawn from these observations. Since the infection of a root-canal and the subsequent suppuration of the periapical tissues does not differ from any other wound infection, it is a priori logical to assume that the remedy is also suitable for the treatment of such cases. (3) Crucial experiments to test these hypotheses. Bacteriologic tests of the infected root-canals before and after treatment verify the general claims made for the therapeutic efficiency of dichloramin-T. (4) Final verifications drawn from a second set of collected facts. After one year of observation, clinical inspection of a set of experimental cases, verified by roentgen pictures taken at suitable intervals before and after treatment, pronounces the complete eradication of the initial disease focus, hence a cure. CASE HISTORIES. Aside from the momentous question of sterilizing an infected root-canal, the eradication of the sequences of pulp gangrene, i.e. apical infection, is equally as important. Here the innoxiousness of the employed drug is especially of vital significance, hence all such compounds as exercise a deleterious influence upon the soft periapical structures must be rigidly avoided. Compounds which are generically classified as caustics, such as concentrated solutions of formaldehyd, phenol, the mineral and certain organic acids, and most metallic salts, should not be employed for the treatment of infected periapical tissues; they produce necrotic areas which furnish a suitable pabulum for those organisms contained in the deeper structures which have not been destroyed by these superficial coagulants, and, incidentally, most metallic salts produce marked discoloration of the tooth structure. The eradication of infected foci about the apices of teeth by the application of drugs is an extremely mooted question. Aside from the results obtained with electro-sterilization, i.e. the utilization of available chlorin, the writer is not aware of any other drug or drug compound, (Fig. dichloramin-T application. The latter was renewed four times at intervals of about fortyeight hours. As this was an experimental case we did not fill the root-canals at once after the last treatment. A second radiograph was taken on January 9, 1918, with the following results: Rarefied area had become lighter and smaller in second picture. 6.) Pain had subsided. Bacteriologic examination of root-canals negative. The rootcanals were filled. Radiogram taken on April 30, 1918, with the following results: Rarefied area very much reduced. (Fig. 7.) A new shell crown was now put over the tooth, and the last picture taken, on June 17, 1918, with the following results: Rarefied area reduced to a light shadow. (Fig. 8.) Tooth has given perfect satisfaction. On inspection, October 2, 1918, no visible disturbance noticed. Patient refuses to have another X-ray taken. Case II. Mrs. M. H., forty-five years. Lower second premolar has a metal filling. FIG. 9. The tooth reacts painfully at intervals; sore on tapping. Roentgenogram shows a marked rarefied area about the apex. (Fig. 9.) open for twenty-four hours. August 3d, routine treatment with sulfuric acid and sodium dioxid. Three treatments with dichloramin-T. Roots filled August 8, 1917. (Fig. 12.) A |