moval of the source of the mouth infection. I have seen three such instances. In one case the gland became greatly enlarged after the operation, exophthalmos occurred, and a tachycardia of from 140 to 160 developed. Before the operation absolutely no thyroid symptoms were present except a slightly enlarged gland."

"For now nearly two years, at a public tuberculosis institution, we have examined the mouths, corrected the teeth, and removed the sources of infection of every patient who entered the institution, and owing to this preventive treatment we have had less tonsillitis, fewer sore-throats, less indigestion, and less influenza and colds than we had before we began these mouth investigations."

The classical view of the periosteum as the reparative agent in osseous injuries and losses is controverted by numerous observations afforded by war wounds. In the adult, the property of bone repair or of bone formation is inherent in the bone itself. It is in the irritated bone affected by an osteitis that there arises the process of ossification. This phenomenon in the adult is therefore exclusively pathological-inflammatory-from beginning to end.

Some extensions of these views into the practical fields of war surgery are― —(1) If all else goes well it may be unnecessary to remove splinters and fragments of bone too soon from wounds; their presence there acts as an irritant and accelerates the process of repair; (2) on this basis the paradoxical cure of pseudo-arthroses following the development of an attenuated infection becomes understandable; (3) the mechanism of osseous grafts becomes in part more intelligible, where these are known to occur in the absence of periosteum.

[Pacific Dental Gazette, San Francisco, September 1917.]

Impressions for Full Dentures, and a Technique. By G. E. WILSON.

From the modern viewpoint the principles underlying impression-taking may be succinctly stated as follows: With full dentures

as large a base-plate area as possible must be covered, the periphery of the denture must extend upon yieldable tissue sufficiently to form a valve-like contact, and there must be contact with the entire area covered by the base-plate.

In other words, an impression to be satisfactory must insure three things-areal contact, peripheral bearing of the base-plate, and extension upon yieldable tissue.

Areal contact means contact over the whole area included within the periphery of the base-plate, but it does not mean uniform pressure over the whole surface of the base-plate. Areal contact can only be secured by a material that flows. Thin mixed plaster best serves this purpose.

To secure peripheral bearing of the baseplate it is best to reinforce peripherally the impression tray with beeswax, over which there is thin plaster. The wax secures the required compression over the desired portions of the impression, and holds the soft tissues firmly and evenly against their bony foundation.

The essential part of a base-plate to be extended on to yieldable tissue in order to obtain retention is the palatal border from the external portion of one tuberosity to the external portion of the other. The palatal extension upon yieldable tissue should be oneeighth to one-fourth inch in width. The direction for the extensions upon the lower denture is upward and upon the upper denture the extension is downward.

[New York Medical Journal, November 10 and 17, 1917.]

A Study of Some Functional Inefficiencies of the Teeth Associated with Occlusal Anomalies. BY MILO HELLMAN.

Hellman summarizes a somewhat extended essay in the form of more or less time-worn conclusions: (1) The efficiency of a denture is dependent not only upon the full complement of teeth in normal occlusion, but also upon each tooth being complete in its form, integral in all its parts, and secure in its attachments to the supporting structures. (2) With the loss of one unit of a denture the functional efficiency is reduced to a vastly greater extent than that represented by the relative numerical proportion of the teeth in that denture. (3) The teeth, though vitally

concerned in the mastication of food, constitute at the same time important adjuncts in the perfection of the functions of respiration and of speech. (4) With every digression from the normal in occlusion affecting the process of mastication, there is also a corresponding deviation from the normal in respiration and speech.

Considered as a part of an educational propaganda among the medical profession, the article doubtless is justified. It contains frequent reference to concrete cases, and is very satisfactorily illustrated by many pertinent models.

[Journal of the National Dental Association, October 1917.]

Persistent Chronic Apical Inflammation and Its Treatment. BY JOHN S. MAR

SHALL.

The value of this paper lies in the novelty of the therein outlined method of treatment -novel only in the sense that it is a method of great rarity today, though at least twenty years ago Marshall made it public. The title of that early paper clearly tells the story: "A Plea for the Extraction and Replantation of Teeth for the Cure of Persistent Alveolar Abscess."

The instruments required for this operation are a dental engine, 1 pair of forceps, 2 curets -1 straight, 1 curved-1 one-half inch carborundum stone, 1 spear-pointed drill, and 2 round burs.

Previous to the operation an impression is taken of the region of the tooth in question, and a swaged splint is prepared. Great care must be taken in the extraction of the tooth, avoiding scratching the enamel or fracturing the crown. As soon as the tooth is removed place it in a mercuric chlorid solution (1: 500 of water) at 103° F., for at least five minutes. (Why Marshall does not suggest substituting one of the hypochlorite solutions for the mercuric chlorid is not apparent. They at least would be well worth the trial.) Curet the socket, irrigate with warm mercuric chlorid, and pack with sterile gauze. Open the tooth through the crown, cleanse the rootcanal thoroughly, and remove the diseased portion of the apex. Enlarge the root-canal, and give retentive shape for a gold filling; do likewise for the opening or the cavity in the crown. Irrigate the root-canal with the

Finish

mercuric chlorid solution, and replace the tooth for at least ten minutes in the solution. Fill the root canal with chloro-percha and gutta-percha points, fill the openings of the apex and the crown with gold. off carefully, as roughness of the root-apex will retard healing. Replace the tooth in the mercuric chlorid solution for at least five minutes. Remove the packing from the alveolus, replant the tooth, and cement the splint in place.

Crowned teeth are not suitable cases for this operation, because of the danger of injuring or breaking the artificial crown in extracting the tooth. This method is also contra-indicated in the case of maxillary molars with divergent roots, and occasionally mandibular molars with convergent roots. The radiograph will give this information.

Theoretically this method possesses merit. Its radicalness insures the removal of an exactly sufficient length of the tooth root, and the proper filling of the canal and closure of the root-apex. Its simplicity facilitates success without as high a degree of technical skill as is required of the operator for the usual method. Finally, this procedure appears to have a much wider range of applicability than is possessed by the more common method. Details, such as the character of antiseptic into which the tooth is immersed and the manner in which the root-canal is filled or the apical opening occluded, may be modified at the discretion of the dentist.

A priori there appears to be no justification for the present unpopularity of the method, and Marshall assures us that clinically a large majority of teeth can thereby be saved and made useful members of the dental economy. In his hands it has proved eminently successful.

[Lancet, London, November 17, 1917.] A Case of Congenital Angioma of the Tongue. BY FRANK M. HUGHES.

This report is merely a brief note. The case concerns a man of twenty-six years. Examination revealed a reddish-blue growth, the size of a large marble, situated on the dorsum of the tongue, well-defined with raised edges, and smooth to the touch. On pressure the growth is reducible in size, but immediate refillment follows release of pressure. No pain has ever been caused by the growth, and

there has never been ulceration or hemor

rhage from it. At the age of sixteen years the tumor had became as large as a marble, causing difficulty in mastication. This led to a condition of indigestion which became chronic.

Hughes decided not to remove the growth, as it is of the cavernous type. This would necessitate the loss of a large portion of the tongue and entail the consequent serious impairment of function of that organ.

[Medicine and Surgery, St. Louis, May 1917.] Paralysis of the Facialis Caused by Salvarsan. By D. W. MONTGOMERY AND G. D. CULVER.

Salvarsan, by virtue of its arsenical content, combines a very slight degree of neurotrophism with a high degree of toxicity toward the treponema pallidum. The case here reported involved profound paralysis of both facial nerves, with a less marked implication of several other nerves and nerve systems.

In the patient, referred for anti-syphilitic treatment, there was a gradual increase in the incidence of disagreeable reactions, progressing evenly with the administration of the drug. A tentative explanation of this apparent "idiosyncrasy" is to regard these nerve affections as a repercussion on the nerves by the syphilitic virus consequent on giving salvarsan. The occurrence of such an accident as that recorded here, as it usually occurs in the early stages of syphilis and after the administration of salvarsan, would indicate some interlocking effect between the infective agent and the salvarsan.

[Science, December 21, 1917.] Why Chloroform is a More Powerful and Dangerous Anesthetic than Ether. BY W. E. BURGE.

It is a common observation that the amount of chloroform necessary to produce deep narcosis is less than that of ether, and that the period between slight and deep anesthesia is shorter and the lethal dose smaller with chloroform than with ether. Acidosis, resulting from the decreased oxidation in anesthesia, is much more likely to occur, and to a greater extent with chloroform than with ether.

The author adduces some evidence that makes it probable that catalase (an enzyme in

the tissues which possesses the property of liberating oxygen from hydrogen dioxid) is the enzyme in the body principally responsible for oxidation.

The decreased oxidation in anesthesia, and the probable importance of catalase in oxida tion, suggested the solving of the problem in the title by determining whether catalase is decreased more quickly and more extensively during chloroform anesthesia than during ether anesthesia, parallel with the greater decrease in oxidation and the quicker and more powerful action of chloroform. Cats were used in the experiments.

Ether produced a gradual decrease in the catalase produced, while chloroform produced a very abrupt decrease during the first fifteen minutes of narcosis. "The more powerful and dangerous effect of chloroform as an anesthetic is attributed to the fact that chloroform is more potent than ether in producing a decrease in catalase, both by direct destruction of the catalase of the blood and by injuring the liver, thus decreasing the output of catalase from this organ, with resulting decrease in oxidation. The specific action of anesthetics on the nervous system, according to this hypothesis, is due to the greater solubility of the lipoids of nervous tissue, which facilitates the entrance of the narcotic into the nerve cell, and thus exposes the contained catalase more directly to the destructive action of the drug."

[International Journal of Surgery, December 1917.] Significance of Dental Stigmata. BY J. S. WALL.

Wall (Arch. of Pediatrics, October 1917) emphasizes the great importance of changes in the first permanent molar in the diagnosis of congenital syphilis. The changes in this tooth may be the only dental deformities in some instances, and are sufficiently characteristic to present no diagnostic difficulties. There is an erosion, not the erosion of wear only, but a disintegration of the grinding surface. to which this term is applied in the absence of a better one. This erosion is irregular in form; the surface of the molar for a third or a half or even the whole of its surface is pitted, excavated, and discolored. There is often a pulpy looking mass of a dirty yellow color occupying most of the face of the crown.

margined, as it were, by the line of cusps ordinarily found on the molar teeth. The tooth has been called the "honeycombed molar of hereditary syphilis." Wall also speaks of it as the "mulberry molar," likening the worm-eaten center of the cutting surface to the appearance of the tip of a mulberry.

[New York Medical Journal, November 10, 1917.]

Tuberculoma of the Tongue. BY CARL E. MUNGER.

The case was that of a man, age thirty years. On the dorsum of the tongue, at the junction of the middle and posterior thirds, in the median line there was a crateriform cavity. In this respect the case markedly deviated from the usually reported situation of tubercular lesions of the tongue; almost invariably these occur either on the tip or sides. This lesion being on the dorsum occupied a site on which usually a gumma is found. At the bottom of the crater there there was a marked ulceration covered with a yellowish slimy secretion, and from the central ulceration were narrow, sharply marked ulcerations radiating to the circumference of the thickened and indurated mass, whose surface color was yellowish. The slightest pressure conditioned an exquisite tenderness with much pain at every movement of the tongue. This pain was localized and not radiating when the tongue was at rest. There was present also the condition known as nigrities. If the condition were primary and strictly local, or if even accompanied by an ameliorating systemic infection, the prognosis would be favorable.

[Journal of the National Dental Association, September 1917.]

The Present Status of Dental Bacteriol= ogy. BY K. F. MEYER.

This is a valuable attempt to analyze and correlate the data already published on this extremely broad and refractory topic. Meyer's article would be justified, if by nothing else, at least by the wealth of reference to original publications. What is pertinent to oral bacteriology in these references is often purely incidental to the main line of thought of the investigator. This paper emphasizes the modern need of a thorough resurvey of oral

fauna and flora by the most approved current methods and standards.

The plan of Meyer's summary consists of 4 topics: (1) Bacteriology and protozoology of the mouth cavity; (2) microbiologic stu dies in relation to dental caries; (3) bacteriology of oral abscesses, chronic periosteitis and osteitis dentalis, and their importance as foci of systemic disease; (4) the etiology of pyorrhea alveolaris from the viewpoint of recent bacteriologic and protozoologic studies.

Under the first topic the principal generalities may be stated as follows: The bacterial content of a clean mouth, on account of the neutral or slightly alkaline reaction, is aerobic and facultative anaerobic, and poor in true saprogenic organisms; in a dirty mouth the saliva is alkaline and favors the growth of anaerobes, and therefore putrefaction is evident; the oral organisms have a well-adapted idiosycrasy for the buccal cavity, and are found outside this cavity only under pathogenic conditions, and then never in the intestines. Under pathologic conditions a shifting of the relative numerical dis tribution of one or of several types of bacteria of the normal mouth may occur.

The section on dental caries is essentially an exposition of Kliger's work (Journ. Allied Dental Societies, 1915). Meyer's paper was prepared before the appearance of Howe's studies in the COSMOS (October 1917, vol. lix, p. 961).

From a consideration of the data collected under the third category, Meyer concludes that the experimental proofs that the microflora of chronic foci of infection play a very important rôle in the causation of systemic diseases are not as yet entirely convincing. It is absolutely erroneous to conclude that chronic alveolar periosteitis and osteitis always represent a potential menace to the health of the human body. Predisposing factors, like preor co existing disease, fatigue, etc., are vastly more important than most dentists realize. One should always suspect the presence of a pre-existing disease as an underlying factor in oral sepsis before mutilating dental operations are undertaken.

Naturally, under the fourth topic, some attention is given to the protozoology of pyorrhea alveolaris. Meyer believes that the final verdict will be that Endamoeba gingivalis has no causal connection with pyorrhea, or that it

is one of many factors responsible for that condition. It is the impression of the author that probably only bacteria common to the oral cavity will be found, and that their relation to pyorrhea is the same as stated for the apical abscesses-namely, the mere presence of these bacteria means nothing, but it attains pathologic significance in this relation when associated with what is generally designated as lack of resistance (from local irritation at the gingival margin or poor nutrition and ill health).

[Presse Médicale, Paris, August 9, 1917.] Cartilage Transplantation in Extensive Wounds of the Lower Jaw. BY MOR

ESTIN.

This is a report of five cases where, to make good extensive losses of tissue, transplants of costal cartilage were resorted to. The results were successful. Eight to ten months after transplantation none of the transplants showed any tendency toward resorption. Esthetically the results were gratifying, and functionally the condition was much better than it could have been without the procedure. In all cases there had been double or greatly comminuted fractures, together with widespread injuries of the soft parts.

[Medicine and Surgery, St. Louis, March 1917.]

The data from seven personal cases are correlated. From a general viewpoint there is a certain similarity between the calculous disease and septic infections of the ducts of the salivary glands and the same diseases in the bile and other excretory ducts, and it is not improbable that the different manifestations of salivary duct irritation and inflammation are as closely related to each other as are those of the bile ducts. The symptoms are essentially obstructive, with an intermittent flow of saliva or of pus and saliva. It may be that a number of cases reported as intermittent swellings, tumors, hernia, recurrent enlargement, etc., of the salivary glands are cases of actual stone irritation or obstruction. The presence of stone is not always easy to detect. In the submaxillary ducts the presence of stone is apt to dominate the picture, while in the parotid, in the absence of demonstrable stone, it is the obstruction,

and possibly the inflammation, upon which attention is focused.

Another phase of this subject is that of acute septic infection of the salivary glands, frequently described as secondary or metastatic abscess. Recent opinion has been gravitating away from this view to that which holds that most, if not all, of these cases were ascending infections of the excretory ducts. However, the seven cases described and analyzed in brief by Blair "lead one to think that possibly the older surgeons were not wrong in their metastatic conception of this particular phase of parotid infection."

The treatment is outlined, but this does not permit of abbreviation.

[Lancet, London, December 8, 1917.] Two Cases Illustrating Plastic and Dental Operations. By H. D. GILLIES.

A Few Notes on the Treatment of Gunshot Wounds of the Mandible and Maxilla. BY W. KELSEY FRY. [American Journal of Surgery, New York, December 1917.]

Healing of Lower Jawbone Defects in War Cripples. BY J. F. S. ESSER.

In an editorial in the Lancet of December 15, 1917, attention is focused upon the first two of the titles given above. The following remarks are of more than passing interest. In the carrying out of the procedures for the repair of the jaws and of the overlying soft parts the fundamental principle must be grasped that the surgeon and the dental surgeon should participate in the work, if the best results are to be obtained. The skilled assistance of the dental surgeon is necessary to obtain perfect replacement of the fragments; the co-operation of the two is essential. Fragments of the bone almost separated from the soft tissues may survive and assist in the union of the bone, and it is therefore of great importance not to remove unnecessarily any pieces which give the least hope of survival.

It is only the first case of Gillies' article which bears upon the work of the military dental surgeon. The case history is given in considerable detail, including the surgical procedure; six photographs facilitate its visualization. The author describes this case as a re-formation of the chin and lower lip by