SECTION OF THE INFRA-ORBITAL AND INFERIOR

DENTAL NERVES FOR NEURALGIA.

BY JOHN T. HODGEN, M.D.,

MISSOURI,

THE operations usually performed in the section of these nerves are tedious and difficult, and result in deformity. Those which I now describe and have repeatedly performed, are easily and rapidly executed and leave no deformity.

In making the section of the infra-orbital nerve, it is proposed to divide the nerve in the spheno-maxillary fissure, and in the report of this operation, made by myself to the Missouri Medical Association in April, 1876, I gave credit to Dr. John Green, of St. Louis, for the suggestion as to the mode in which this section may best be made. He proposed that an opening be made on the inferior border of the orbit down to the bone; that an elevator be then used to separate the soft parts from the orbital plate of the superior maxillary bone, and reaching the posterior border of this surface, the nerve is found lodged in the groove terminating in the infra-orbital canal.

With a blunt hook, having a curve about one-sixteenth of an inch from its end, the groove in the bone at its posterior part is readily found. It is well known that the infra-orbital canal runs almost directly backward from the infra-orbital foramen, and that this foramen is situated directly under the middle of the palpebral fissure, and two lines below the border of the orbit.

The groove at the posterior part of the canal being found by the blunt hook, the hook is moved to the inner side and is pressed hard upon the bone, and pushed backward until it passes over the posterior border of the orbital plate of the superior maxillary, and is then turned outward, and made to sweep behind the posterior termination of the groove in which the infra

orbital nerve and artery are lodged.

Thus both vessel and nerve

are caught in the hook. A straight, narrow scissors, guided by the shaft of the hook, is carried backward between the hook and the orbital plate of the superior maxillary, until the nerve is reached; it is then cut. To this proposition of Dr. Green I added the following part of the operation: It consists in separating the soft parts from the facial surface of the superior maxillary, down to the infra-orbital foramen. The blunt hook is made to sweep round this foramen, and thus the infra-orbital nerve and artery, at their exit from the bone, are hooked up; using the hook as a lever, the nerve is readily drawn out of its canal, and the portion of it which extended from the sphenoidal fissure to the infra-orbital foramen is thus removed.

To make sure that the union will not again be accomplished along this track of removal, a needle carrying a double ligature is passed through the incision below the orbit, and made to terminate in the mouth behind the upper lip. Through the loop before the ligature is drawn through after the needle, is placed the now loosened end of the nerve, and as the loop is drawn through, the nerve follows, so that the end which formerly occupied a position at the spheno-maxillary fissure is now lodged on the mucous membrane of the mouth under the upper lip. A careful regard to the anatomy of the parts will enable any one to perform this operation. I have been surprised to have so little extravasation of blood within the orbit after the section of the infra-orbital artery as it enters the infra-orbital canal.

One can make sure that the nerve is completely divided at its entrance into the canal, from the loss of sensibility of the lower lid, the side of the nose, and one-half of the upper lip of the side corresponding to that operated upon. The operation after section of spheno-maxillary fissure will of course be painless.

The other operation, that of section of the inferior maxillary nerve, I have proposed and done as follows: With a strong knife a cut one inch long, well down to the bone, is made in the length of the bone, beginning at the base and a little to the inner side of the most prominent part of the coronoid process of the inferior maxillary bone, and extending forwards. The periosteum is now separated to the width of one fourth of an inch, and a small spear-pointed drill driven by a dentist's engine

1 See Transactions of the Missouri State Medical Association, 1876.

has its point placed one-fourth of an inch in front of the posterior termination of the incision in the soft parts before mentioned, just behind the site of the last molar tooth. The drill is directed downward, backward, and a trifle outward. The firm shell of bone is penetrated and quickly passed. Any unequal resistance to the right or left after coming into the cancellated tissue of the ramus of the bone, will indicate to the surgeon that the hard shell on the outer or inner side is being cut. If the drill is spear-pointed, as directed, it will not cut through this dense bone on the sides, but will follow the cancellated tissue in the centre. In a few seconds the canal containing the blood vessels and nerve will be reached and its thin wall opened. A severe twinge of pain and a free flow of blood will announce that the nerve and vessels have been cut, and this should be done as near as possible to the posterior dental foramen. (I will just here remark that, in this operation, I have never seen sufficient hemorrhage to excite the least anxiety.) A burr is now made to substitute the small drill. With this the opening is enlarged, and the nerve is again reached. This, of course, may be known by the pain which is felt by the patient when the central end is touched. The burr is directed forward, and the nerve is cut towards its distal termination. The burr is moved freely to the right and left to make sure that all the fibres of the nerve are severed. Of course the loss of sensibility in the lower lip and chin will indicate the success of this step of the operation.

The next step in the operation is the withdrawal of the nerve from the canal between the posterior dental and mental foramina. An incision is made opposite the bicuspid teeth, at the junction of the lips with the gum. The soft parts are then detached with an elevator down to the mental foramen. The blunt hook is made to pass around the foramen, and thus hook up the nerve. The hook is used as a lever, and the distal termination of the nerve being next to the loop, the portion occupying the body of the bone is drawn out; of course breaking off those filaments that go to supply the teeth.

Since February, 1874, I have divided the infra-orbital and superior maxillary nerves twenty-four times on thirteen patients, as follows:

CASE I.—Judge B. had suffered nine years with an intense pain in the infra-orbital nerve. All the teeth of the half of the upper jaw had been drawn February, 1874. I made a V-shaped

incision over the infra-orbital foramen, and trephined its facial surface. I broke down the inferior wall of the orbit, and removed about an inch of the nerve. He was free from pain until April, 1876. In October, 1877, the operation was repeated. I found the nerve had been reproduced. After this he had no pain for four or five months. In October, 1878, I operated again; this time by the method which I have now described. Since that time he has not suffered the same character of pain. that he had before the operation, but he has had occasional attacks of neuralgia; not so severe as to incapacitate him for work.

CASE II.-Jos. B., aged sixty-two. Been suffering with neu ralgia of the lower jaw two years; operated July, 1874. This operation consisted of severing the inferior maxillary nerve, as above described, and with a burr cutting out a section, perhaps three-fourths of an inch. In November, 1874, he reports himself well. I know nothing of him since.

CASE III.—Mrs. Sarah M.; had neuralgia in the lower portion of the face twenty-five years. All the teeth of that side of the lower jaw had been removed. I divided and drew out the nerve January, 1875; she was entirely relieved of pain. June 24, 1875, she writes: I have had some slight indications of return. October, 1878: I had no pain for a year; the pain returns at intervals; I am sometimes free from pain two or three months at a time.

CASE IV. Mrs. L., a feeble woman, aged 55; suffered ten years. Pain referred to the lower jaw; cut the inferior dental June 25, 1874. Was entirely free from pain until May, 1875, when she suffered again. November 14, 1875, I divided and drew out the inferior dental nerve; since that time there has been no pain in the inferior dental. The patient suffered from infra-orbital neuralgia, June 25, 1876; I cut and drew out the infra-orbital nerve; since that time she has been entirely free from pain; has grown fleshy and strong.

CASE V.—J. B. C., aged 47; suffered nineteen years. February 12, 1876, I trephined superior maxillary, broke down the floor of the orbit and removed one inch of infra-orbital nerve. May 24, 1876, he writes: I have suffered slight pain since in the lower jaw during changeable weather. In 1879 he writes: I am entirely well.

CASE VI.-A. H. H., perhaps aged 50 years; been suffering

nine years with neuralgia of the inferior dental nerve. In November, 1875, cut and drew out the nerve. April 16, 1876, he suffers very little; has pain in the upper jaw and upper lip. April 15, 1877, cut and removed the infra-orbital. Pain returned in two weeks after the operation; has continued, though not so severe pain, generally at night.

CASE VII.-J. B. C., aged 47; suffered nineteen years, infraorbital nerve; operated February 12, 1876. May 24, 1876, writes: Suffered slight pain since the operation, in the lower jaw, especially during changeable weather; 1879, he is entirely well.

CASE VIII.-Mrs. P., aged 65 years, a delicate lady; suffered five years. May 10, 1878, divided the inferior dental, and attempted to draw it out. The nerve broke and was not satisfactorily removed; free from pain for eight months. May 10, 1879, cut the nerve again, and drilled the bone at numerous points, perhaps moving a section an inch and a half long; has had some pain since the last operation, but has suffered much less than before.

CASE IX.-O. F. B., aged 46; suffered fifteen years; inferior dental; operated on October, 1878; no pain for twelve months, and the nerve was not satisfactorily removed. March, 1880, returned suffering; the nerve was again divided, the bone drilled at several points, I think I removed one inch and a quarter, perhaps, at the last operation; the pain was at once relieved; I have not heard from the patient since.

CASE X.-Dr. P., aged 60; a robust man, suffering neuralgia of the left inferior dental nerve in 1876. I cut the nerve, but did not successfully draw it out of the canal, October 29, 1879; he was entirely relieved for seven weeks. On the 15th of February, 1880, I drilled the bone again without relief. On the 24th I again drilled the bone at a number of points, the first point being further back than before. A good deal of inflammation followed, but there was no more of the old pain.

About April 1st, 1880, had hemiplegia involving the left side, from which he is slowly recovering. Memory is failing, intellect feeble. Dr. Stevens, of Chillicothe, reports, May 26, 1880, "a loud systolic murmur; impulse very marked." The patient has probably aortic insufficiency and consequent hypertrophy of

heart.

CASE XI.-Dr. L., age 35, March, 1876, has had severe pain

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