and sixty-two years, as we have in no way changed middle age or advanced many more into old age. Death which is not accidental is due to the effects of the action of microbes a result that may be acute and sudden, or chronic and slow in its termination.

The contagious character of various diseases has been appreciated for untold ages, and it has been known that certain of them developed some change in the individual which rendered him immune to a second attack of the disease. The first disease for which a vaccine was developed was that of smallpox, and while used in China and India long ago, it was first used in Europe in Belgrade, and was brought to the English-speaking people by the discoveries of Jenner.

A study of the blood in disease, as varying from its condition in health, and the action of its cells in developing antibodies, has been of wonderful value to mankind. Through this study, acute diseases that create an immunity are reduced in morbidity and mortality by increasing the resistance of the patient, as in tetany, typhoid, paratyphoid, ty phus, yellow fever, etc. The innumerable diseases that formerly decimated mankind have been almost driven from the earth.

It is because of this wider knowledge of medicine that it has been possible to continue the present war without the enormous armies being destroyed by diseases which would long since have brought the war to an unsatisfactory termination.

We find, then, that there is developed in the blood stream, in acute diseases and fevers, an immunizing agent. On the other hand, with certain diseases there is, at some place in the body, a small focus of bacteria continually maintained, developing not an immunity but an anaphylactic reaction of the constant supply of microbes or microbe toxin instead of elevating the resistance of the patient against the germ. Such persons are subject to recurring colds on the slightest provocation, recurring neuralgias, recurring myositis, muscular rheumatism so called, lumbago, sore muscles

of the back and neck, etc., and it has been enough in the past for the patient. to say he is subject to such trouble and for the doctor to make local applications and allow time to complete the cycle of improvement until, from any cause, lowered body resistance again reinstates the liability to an attack-and any part once affected by a microbe becomes more liable to repeated attacks.

We have also protein poisoning. Many persons are unable to eat various grains or berries, milk, fish, etc., which cause them to develop asthma or chronic diseases of the respiratory tract, or of the mucous membrane or skin, shown by local swelling, diarrheas, or eczema.

Although there are but few places in the body in which man quite regularly carries bacteria, they are always in the mouth, often in the tonsil and about the teeth in pyorrheas, alveolar abscesses, and buried crypts of tonsils. All tonsils that are capable of reacting to the infection and are of good size, 3 or 4 on the scale of 4, are usually not the cause of chronic disease but of strictly local involvement, and when inflamed temporarily, develop systemic disturbances. The position is most difficult for many physicians who have but recently come to a knowledge of the danger of a focus in these instances, not realizing that the blood stream is the carrier of the infection. In such cases the localizing trouble in the sciatic nerve or in the joint did not begin there, but arose from the existence of bacteria in a minute pocket, and if that pocket is under tension the disease is essentially chronic. The physician examines the throat and says the tonsils are not inflamed, or are graded 1 or 2 in size, and cannot be the source of the trouble. The dangerous tonsil is the one graded 1 or 2, without any effects of local inflammation on its surface.

Diseased teeth are often local foci of infection, and the X-ray has been of inestimable value in determining the presence of alveolar abscesses, absorbed roots of teeth, or absorbed bone about the roots. The findings are striking, when positive, but many pockets do not show

in an apparently good picture. The dangerous tooth is a crowned tooth, and if it is necessary, from the seriousness of chronic, recurring diseases which affect the heart, as a myocarditis, or the kidneys, or the joints or nerves, then small tonsils must be removed and teeth most carefully inspected, X-rayed, and, when diseased, extracted on the basis of symptoms, should they be of major importance. Endarteritis, overgrowth of bone about the joints, including the hip and spinal vertebræ, are also due to minor types of bacteria, which are probably in pockets not under tension. I have far less fear where nature loosely holds the bacteria; the dangerous ones are always under tension and in small areas, although we must now come to the acceptance of the fact that the blood of apparently healthy persons often contains microbes.

In our bodies, with almost no evidence of it, are living and growing the amoeba, the syphilitic spirochete in almost every place, the hookworm, and other germs too numerous to mention, and often temporarily doing no more harm than trout in spring water. We have wandering leucocytes with almost the power of animals to leave the blood stream, forage for material dangerous to life, and return to the circulation; and in many of us a little blood drawn and time given for culture will show some kind of microbe to be present. The stomach does not destroy all the bacteria taken into it; some may pass into the blood by the chyle duct, and probably more. commonly enter the blood stream by way of the portal circulation but are destroyed in the liver. The germs in the mouth are carried on into the stomach, and in the great majority of persons there are numerous bacteria living in the gastric juice after all food has left the stomach. The dangerous varieties are those of the acid type, while those of alkaline nature are nuisances.

Of secondary importance to the microbe, from a biologic standpoint, is the chemistry of the fluids of local areas for their environment. This is similar

to the result from seeds planted or blown upon different soils. They may be planted to no purpose on the wrong soil, and they may be blown everywhere to take growth to advantage in proper environment. Bacteria carried throughout the body by the circulation are able to take up local growth only when thus carried to a given area. This accounts for the specificity of bacteria in their location causing acute and self-limited diseases, or chronic recurring or relapsing diseases. The acidity, the oxygen tension, and the condition of the general health, or local injury, may all be factors. Some forms will only grow in a certain place, as poliomyelitis in the brain and spinal cord, others in the sheaths of nerves, the first causing acute conditions, self-limited, and the latter, recurring neuritis. Thus we have rheumatism, appendicitis, gall-bladder inflammations. and ulcers of the stomach, valvular diseases of the heart; in fact, nearly all of the local and general diseases of which we have knowledge are thus produced.

The factors of safety are largely within the control of man, in preventing diseases, and in the transference of immunizing resistant bodies, such as have been developed for the cure and prevention of diphtheria, typhoid fever, smallpox, poliomyelitis, and many other affections.

Diseases of middle life are increasing. They are microbic, of a chronic, recurring character and are carried into the blood stream from a few foci, the mouth being the source of greatest danger. A crowned tooth is not a crown of glory, and may cover a multitude of germs. Modern dentistry is relieving the world of much of its misery by watchful care of foci connected with the teeth, and the trend of modern medicine and dentistry is bringing their fields again closely together. Dentistry should be a department of medicine, as it is as closely associated with medicine as are the specialties of the eye, ear, nose and throat, etc.

[See also Discussion, as reported under "Proceedings of Societies," this issue.]

I

N these days, when our country calls upon each and every citizen to do his bit in the suppression of Prussianism, it is the duty of every dental practitioner to be fully prepared to render expert service.

The mills of progress must go on, even though a great many of our people are in some field of service. Those who are to carry on the work of maintenance, construction, and preparedness must not be burdened with unnecessary pain or trouble. The efficiency of a person, group of persons, or community can be seriously impaired by the ravages of disease or needless suffering, and it is within the province and duty of the dental profession to eliminate as much unnecessary pain as is consistent with present-day teachings. We can at least approach the ultimate ideal of a safe, painless oral operation, and it is an undeniable fact that in all time there has never been a better or safer anesthetic than the procain-suprarenin combination. Therefore we should all familiarize ourselves with this drug and its uses.

The new name, "Procaine," is under license of the Federal Trade Commission, in place of the old name, "Novocain."

As far back as 1853, experiments were conducted along the lines of local anesthetics, but for the most part they were unsatisfactory until Koller demonstrated the anesthetic properties of cocain, in 1884. In 1885, conduction anesthesia was first employed by Halsted, who injected the anesthetic in the vicinity of the inferior dental nerve rather than in the immediate vicinity of the tooth.

Braun, to whom the title of "father of modern local anesthesia" is applied, made the suggestion of the addition of the suprarenal capsule to the injecting solution.

I need no more than mention the danger of the use of cocain, because of its toxic effect. Procain fulfils the requirements of a safe and effective anesthetic, inasmuch as under satisfactory conditions it will permit the most delicate operations to be performed in peace and quiet, with very little hemorrhage, without haste or interruption, and with very little after-pain.

ANESTHETIC PROPERTIES OF PROCAIN.

Procain, which is seven times less toxic than cocain, occurs in small, colorless, and tasteless crystals, is soluble in water and less so in alcohol. It can be heated to 120° C. without decomposing. It produces the general alkaloid reactions and has the same effect on the peripheral sensory nerves as cocain. Procain creates no irritating effect upon the most sensitive tissues even when applied in strongly concentrated solutions, and no systemic effects are perceptible. It does not even affect the respiration, circulation, or cardiac function.

The 2 per cent. solution is the best for both infiltration and conduction anesthesia. With few exceptions, even in cases of anemia, neurasthenia, nephritis, arterio-sclerosis, heart diseases, or cases of general weakness, it is not found necessary to weaken the solution. The maximal dose is 0.5 gm. for subcutaneous

injections, but as much as 2 gm. has been used subcutaneously with no bad results. The maximal dose of 24 mils, or 12 syringefuls, of a 2 per cent. solution is more than is ever called for in dentistry. The U. S. P. IX has discarded the term "cubic centimeter" (abbr. Cc.) on the ground that the United States Bureau of Standards declared the term a misnomer, there being a slight difference between the thousandth part of a liter and a cubic centimeter. The word "mil," the first three letters of the whole word millimeter, has been adopted, and therefore in speaking of dosage I shall use the word mil in place of cc.

SUPRARENIN.

Suprarenin has great anemia-producing power and is a strong astringent. It is used with procain to contract the capillaries and tissues locally, in order to prevent absorption and infiltration into the soft tissues, thereby strengthening the anesthesia, and also to decrease bleeding in certain operations. It is more stable, keeps better, and is less toxic than any of the other anemia-producing substances. It is easily decomposed by free alkali, air, and heat. It is the strongest hemostatic and astringent known. For general use a solution containing 0.000,0150.000,02 gm. of synthetic suprarenin to 1 mil (or a 0.0015 -0.002 per cent. solution) is the best.

Therefore the combination of procainsuprarenin possesses the five essential qualities that a local anesthetic should possess to be satisfactory:

(1) The substitute should not be inferior to cocain in its anesthesia-producing power.

(2) It should be relatively non-toxic. (3) It should have no irritating action. even on the most delicate tissues.

(4) It must be easy to combine with suprarenin, and when so combined it should not lose its anesthesia-producing power; neither should it affect the action of the suprarenin, and it should be soluble in water.

(5) It must be unaffected by boiling.

Ten Ringer tablets to 100 mils of water, boiled for fifteen minutes, give the Ringer solution.

syringes, one mounted in a short hub The apparatus consists of two Fischer with a 26-mm. and the other in a long hub with a 42-mm. iridio-platinum needle. It is better to use iridio-platinum needles, because it simplifies matters in that they do not need to be boiled before using, can be used again, and are always mounted and ready. Iridio-platinum needles should be sterilized in the flame. They are easily sharpened by the use of a sandpaper disk. Steel needles are not so applicable because they break rather easily, oxidize, rust, and must be boiled just before using, which requires considerable time. However, because of the liability of needles to break off while injecting, I think it better to use steel needles for conduction anesthesia, conduction anesthesia, because when broken off they are more easily removed surgically. A powerful magnet may be

used for removing them. The syringes should be held on a specially made stand in an all-glass jar containing alcohol. I have found that if extreme methods of cleanliness be employed, and any apparatus used be thoroughly cleansed and sterilized after using, a 99 per cent. solution of alcohol simplifies sterilization and is efficient. Two dissolving-cups, one graduated to 3 and the other to 10 mils, should be kept in absolute alcohol. The cups are made of porcelain and can be easily cleaned with dilute hydrochloric

acid.

There should be one double-corked bottle for Ringer's solution.

Another jar should contain sterile distilled water in which to rinse the syringe and boiling-cup in order to rid them of alcohol. A glass tray in which to keep tablets, wires, wrench, reserve needles, syringe parts, and engine stones is also desirable.

Care should be taken not to handle the tablets, always replacing the cotton, rubber stopper, and cap immediately, otherwise the drug will deteriorate because of contact with air and moisture. If the solution turns pink it is contam inated and should not be used under any circumstances.

REQUIREMENTS OF A SOLUTION PREPARED FROM TABLETS.

(1) The solution should be immediately used after it has been prepared.

(2) The solution should not come in contact with anything except the boilingcup and the syringe. It should not be left longer than is absolutely necessary in the dissolving-cup nor in the syringe. The solution is very sensitive, being air, light, and especially alkalis. affected and chemically changed by heat,

(3) The tablets should be white, and the prepared solution should be the color of water.

PREPARATION OF THE PATIENT.

The operator must inquire as to the health of the patient and have a keen appreciation of the necessity of lessening the amount of suprarenin to be used.

In a few super-sensitive cases when the needle-prick is found to be exceedingly painful and annoying to the patient it is well to administer nitrous oxid and oxygen to the analgesic stage while inserting the needle. A pledget of cotton saturated with a 20 per cent. solution of procain (made from F tablets) and allowed to penetrate slightly into the mucous membrane will also reduce the pain of injection. With a very fine sharp needle in a small syringe one may inject a small quantity before the regular injection is made. Sharp needles lessen the pain of injection.

PREPARATION OF PLACE FOR INSERTION OF NEEDLE.

After placing a small napkin in the mouth about the field of operation, to catch any of the dropping solution, hold the lip away and wipe away all moisture possible. Then with a small pledget of