The Apparatus and Technique Necessary for Successfully Applying Cataphoresis for Desensitizing Sensitive Teeth

The purpose of the clinic was to demonstrate the simple reasons for the very general failure of the profession with cataphoresis, and show how one can have almost universal success. Owing to their crush of duties the executive committee had not been able to provide a patient, so the announcement was made before the meeting that a dentist was wanted as patient who had sensitive teeth, and preferably one who did not believe in Cataphoresis. Dr. Cecil Trotter, of Toronto, claimed to fill all the requirements and offered himself. The application was made to a mesial cavity in the left cuspid. The rubber dam was adjusted, and S. S. White’s low heat sticky gutta percha was packed between the teeth to insulate the joint of the rubber at the neck of the tooth and a distal gold filling in the adjoining lateral.

Very many failures have occurred from faulty insulation. I believe all the apparatus without exception heretofore available had these two principal condemning faults, viz.: First, that they had no measuring instrument that would show clearly just the amount of current that was being used. This is usually only a few hundred-thousandths of an ampere. No instrument heretofore available would show this. This measuring instrument is thirty-two times as sensitive as the S. S. White, one hundred and twenty-eight times that of the Chloride of Silver Dry Cell Battery Company’s instrument, and over three hundred times that of the Van Woert and McIntosh. Most of the outfits offered the profession had no measuring instrument at all. Experiments and experience have shown that three-tenths of a milliampere is a maximum safe current for single rooted teeth, and four-tenths for a two or three-rooted tooth, unless you wish to remove the pulp. Without a measuring instrument too much current can be used after the pulp becomes anesthetized, hence it is a necessity to measure the dosage. The measuring instrument also shows at once a bad insulation or a break in the current, of a faulty connection.

Second. The other condemning fault of the apparatus heretofore available was that the current could not be increased gradually enough to comply with the requirements of the sensitive tooth structure, and hence pain and discomfort were produced in making the application, which does not occur with this if properly operated. (These points were thoroughly demonstrated on the patient.)

The solution used was a saturated solution of cocaine in distilled water so that we might have nothing else present to carry the current. The application was made for fifteen minutes, when the excavating was done with dull burs by a disinterested party, Dr. Ebble, of Louisville, and although the tooth was very sensitive before, it was without sensation now. This condition of anæsthesia lasts from ten to sixty minutes. The result was apparently perfectly satisfactory to all who saw it, and particularly to the patient, for he later secured one of the instruments because of the success of this operation, and writes that it is giving excellent results in his own practice.

Some important points were brought out which are now established beyond controversy by the many using this outfit. Among them were these: that much time is actually saved in the total cases if properly managed, viz., to apply to one tooth while filling another where convenient; that all teeth that can be insulated can be painlessly desensitized if the pulp is not putrescent; that a large number of dentists who were bitterly prejudiced against cataphoresis after using the apparatus heretofore available, are exceedingly enthusiastic over it after using this apparatus.

By request this clinic was repeated on the second day.