"As the results obtained were too uniform to require any detailed history, the sub-committee are content to sum up all they observed in two statements.

"1. That in no instance, under the influence of the electrical current, was there any approach towards the production of local anesthesia.

"2. That in many instances the pain of extraction did seem to be modified or rather changed in character by the currrent; in some instances this change in the character of the sensations developed, seemed, moreover, to be satisfactory to the patients, as in some measure breaking the acute shock of the operation."

REPORT OF SUB-COMMITTEE B.

This committee, consisting of Messrs Perkins, Williams, and Kempton, state :

"We have had one meeting on Friday, January the 14th, 1859. There were two cases for operation. We used the intermittent current, placing one pole in the hand of the patient and attaching the other pole to the forceps.

"The first case was that of a man aged twenty-three years. The tooth to be extracted was an upper molar. After extraction the patient expressed that the sensation produced by the galvanism was much greater than that produced by the extraction. As compared with previous instances in which the same operation had been performed, the present operation was more bearable.

"In the second case a youth of thirteen was the patient. He desired us to remove a first lower molar. This patient expressed that he did not feel much pain, less, he thought, than on a previous occasion when he had had a tooth withdrawn without the aid of the electrical current.

"The sub-committee have no comments to make on these cases, but the cases may be useful as adding to the list of cases already subjected to operation."

REPORT OF SUB-COMMITTEE C.

This sub-committee consisted of Mr Harry Lobb and Mr Kempton. These gentlemen give the history of two cases in which extraction was performed, after the application of the continuous current. They state:

"The patients operated upon by us were both females. We employed in each case a Pulvermacher battery of 120 elements. We placed the end of the positive conductor connected with a moistened sponge (externally) over the jaw; the point of the negative conductor was attached to the forceps,

which were made to grasp the tooth. The current was sustained in each instance for fifteen minutes.

"In neither case was there any evidence of the production of anesthesia. In one case the pain of extraction was modified; in the other the pain was as severe as it might be expected to be without the current."

SUMMARY.

The committee have thus in their possession the records of sixty-eight cases of tooth extraction, in sixty-five of which the anaesthetic value of electricity was tested, with all the care and the knowledge at the command of the observers. Fiftyfive of these operations were performed to test the value of the intermittent current. Ten were performed to test the value of the continuous current. In these experiments every possible modification was introduced. The poles of the batteries were reversed in different cases; the force of the current as indicated by the sensations of the patients was varied; and every necessary precaution was taken to secure insulation of the ope

rator.

The committee, in viewing the whole of the results of the experiments thus performed, find that in much the larger proportion of cases the results were purely negative. In several instances more pain was excited, owing to the application of the current, than if the tooth had been removed at once by simple extraction, in other instances less, while in a few. cases, amounting to five altogether, there was evidence of relief. In three instances this evidence was well marked.

The committee does not, however, put forward these latter five named cases as instances of local anesthesia. It appears to the committee that in all instances where success was apparent, a mental element was called into action, and that the patients at the time of the operation were in a state of partial general insensibility, due probably to hysterical syncope.

In those examples where the patients expressed that the pain was less than they had experienced on previous occasions, the assumed relief did not arise from the fact that the tooth and its neighbouring parts had been rendered dead to external impressions, but from various extraneous causes, of which the committee may enumerate, as most prominent,

1. Diversion of sensation.

2. Less difficulty in extraction as compared with previous extractions..

3. Syncope more or less marked.

4. Differences in the method of operating.

In those examples where the pain seemed to be increased by the electricity, the cause of the increased pain was obvious. The cases were those in which the tooth was exceedingly sensitive, either from recent inflammation of the pulp, from abscess, or from inflammation of the alveolar periosteum. In many of these cases the patient could only bear the gentlest current, and that with much complaint as to the unnecessary addition of pain.

The committee, as will be observed from the history of the observations, made various changes in the mode of applying the electrical current. These changes had reference to the direction of the current, the poles being generally reversed in each experiment, to the force of the current as defined by the sensations of the patient and to the position of the poles in regard to different parts of the body.

The conclusions at which the committee could only arrive as the summary of their combined observations, are

(a) That the direction of the current does not in any way modify the result.

(b) That the force of the current has, equally, but little to do with the issue.

(c) That the method of placing the poles, in regard to different parts of the body, did not appear to exercise any peculiar difference. The effect was mainly the same, ie., when one pole being applied to the tooth, the opposite was applied to the hand, the cheek, the neck, or other region.

As regards the different forms of electrical apparatus and current, the committee are forced to the decision, led solely by their own present inquiries, that the differences in effect are not striking. In nearly the same number of cases, relatively, the intermittent and the continuous currents gave an amount of apparent relief, while in the application of both considerable pain was excited in some particular cases.

The committee feels also, that were it even proven that the electrical current could be so applied as to produce anesthesia of the soft parts and organs, great difficulties would be in the way in making it useful in dental practice; for the tooth structure being a bad conducting medium, the transmission of the current through it, so as to influence the supplying sensitive nerve, would, in the majority of cases, be impossible.

On a final point the committee is unanimous: that in not one instance did any member observe the merest approach to local anesthesia. Neither in the tooth, nor in the surrounding structures, nor in the part of the body to which the opposite

F F

pole itself.

was applied, did any indication of insensibility present

The sum and substance of the labours of the committee, in their practical bearing, is this: that the continuous current of electricity is inapplicable as a local anesthetic in dental operations; that the intermittent current, from being harmless, its use is allowable in practice, by those who may consider it of advantage to produce a diversion of sensation in the patient during extraction; but that as, in a scientific point of view, the electrical force, according to the present knowledge of its application, cannot be accepted as an anesthetic, the committee could not undertake to recommend any special electrical apparatus, nor any particular method of applying electricity in the operations of dentistry.

The foregoing report, having been read, and discussed in detail by the committee, conveys the unanimous opinion of the members.

ON VOLTAIC NARCOTISM IN OPERATIONS ON THE TEETH.

At the time when the Committee were on the point of concluding their preceding observations, the fact was brought forward that by the application of the continuous electrical current in combination with certain narcotic substances, local anesthesia could be produced to such extent as to enable the surgeon to perform several operations without pain. To the process thus invented the name "Voltaic Narcotism " has been applied by its author.

The committee, anxious to ascertain whether the new process could be applied advantageously in dentistry, discussed at a meeting held on February the 5th, the propriety of investigating that point.

It was then moved that experiments should be instituted and added as an appendix to the report.

The resolution was unanimously adopted, and the following observations are the result :

OBSERVATION 1.-The patient was a youth, aged fourteen.

The tooth to be extracted was a lower molar. Into the cavity of the tooth was placed a small plug of lint saturated with a solution containing two minims of tincture of aconite and ten of chloroform. To the positive pole of a Smee battery of twelve cells a pointed conductor was attached, the handle of which was insulated. The point of this conductor was now inserted into the lint which had been placed in the cavity of the tooth. The negative pole was attached to a conductor, with insulated handle, armed at its opposite end with a sponge moistened with five minims of aconite and fifteen of chloroform. The sponge was applied externally to the jaw, and the circuit was thus completed. The current was sustained for fifteen minutes. The making of the circuit was painful, and there was excited in the tooth a burning sensation with occasional sensation of shock through the parts enclosed between the poles. These effects ceased after twelve minutes. On the poles being removed the tooth was extracted.

Result. The patient gave expression to sharp pain at the commencement of the operation, but not afterwards. When the extraction was over, he explained that the grip of the forceps on the tooth was very painful, but that the extraction was but slightly felt.

* OBSERVATION 2.—The patient was a girl, aged fourteen. The tooth to be extracted was a lower left molar. The cavity of the tooth having been cleaned, was filled with a plug of lint saturated with three minims of tincture of aconite and five of chloroform. The Smee battery of twelve cells was used. The point of the negative pole was applied to the cotton in the tooth; the point of the positive pole, surrounded by a layer of wet lint, was applied over the gum in front of the tooth. No evidence of shock was given in closing the circuit. The current was kept up for fifteen minutes and a half, a drop of chloroform being frequently conveyed to the lint in the tooth, at the end of the time named the poles were removed and the tooth was extracted.

Result. The patient, though quite sensible, gave no expression of pain. After the operation she stated that although quite aware of all that was done, she was conscious of no pin whatever. All she felt was "the rising of the tooth from the socket."

The

* OBSERVATION 3. The patient was a woman. tooth to be extracted was a lower molar. The cavity of the tooth was filled with a small plug of lint containing three

* Observation made on Friday, April the 1st, 1859. Present: Dr Richardson; Messrs Harding, Purland, Williams, Thomson, Kempton, and Hockley.