to enable him to get his bearings right and to bend the wire so that the pressure is exerted in the right direction.

Dr. MARCKLEIN: The only anchorage that I can see that we can have in a case such as I have mentioned, must be furnished by the two superior second molars. The other teeth must all be thrown or drawn backwards, and I would like to know if the anchorage on those two teeth will be sufficient to make it possible to throw back all the other teeth. My experience has been that the molars come forward a great deal easier than the others come backward. I can readily see the value of this appliance in the case of one or two teeth, or even four, but here we have an extreme case of ten teeth to be moved, with only two upon which to anchor.

Dr. THOMAS: Move one at a time.

Dr. MORRISON: Dr. McKellops, as long ago as 1865, brought the original Coffin plate from Europe. It was a rubber plate with caps for the molars merely. I have used those plates under Dr. McKellops's order and directions, as I was associated with him at that time and was doing that kind of work particularly. They are very good plates for some cases where the molars are large and you can get good anchorage, but where the teeth are small, with short crowns, they are of no account at all. In the latter class of cases the shape of the teeth is such that if you do not tie the plate with ligatures up above the swell of the tooth, it will slip off. If you tie it above the swell you are obliged to cut into the healthy soft tissues an eighth of an inch.

I offered you this morning an entire substitute for all such inconvenience as this. I said at the outset in my article that these old bungling things ought to be things of the past. I offered you something which can be adjusted at the swell of the tooth. There is not a gentleman who has made a remark that bears upon the point last referred to, since the discussion was opened.

SECTION VI.

PATHOLOGY, THERAPEUTICS, AND MATERIA MEDICA.

IN

The Possibilities in the Treatment of Pulpless Teeth.

PAPER BY A. O. RAWLS, OF THE SECTION.

N pulpless teeth there are two tissues more or less intact and devoid of life, viz., the enamel and the dentine; two tissues still existing, one with a possibility of but very slight break in its nutritive continuity, viz., the pericementum, the other with the probability of numerous breaks in its channels of life, viz., the cementum. In the case of alveolar abscess the same tissues, as above, are usually involved in the same manner, and to the same degree, but there are exceptional cases in which this does not take place. These latter cases are those wherein the abscess does not cause destructive lesions at the apex, or apices, of roots of teeth; as when it occurs at the point of bifurcation of roots, upon the sides of roots, etc. Aside from the conditions mentioned, alveolar abscess may involve, in addition to the above, more or less loss of the periosteum and process in the vicinity of its attack, thus leaving the process in proximity to the abscess either partially or completely denuded of its proper covering. In all pulpless teeth, whether the condition is complicated with alveolar abscess or not, there is, of necessity, a break in the nutritive continuity at the ends of their roots. In all cases of alveolar abscess there exists a similar condition in which the nutritive supply is cut off, either from the cementum or the process, at the point of attack.

I believe it is the generally-accepted opinion that there is but one periosteal membrane between process and tooth; also that this membrane is attached to both process and cementum by minute shredlike prolongations or ramifications of its connective tissue, together with nutrient vessels passing into and out of its substance. This being true, any inflammatory action may, according to the location of its cause, result in an abscess which will destroy the connection either between the process and the membrane, or the cementum and mem

brane, and may ultimately involve an entire dissolution of more or less of the membrane at the seat of disease. It is to the latter probabilities that we may ascribe the differences of opinion relative to the question as to whether all conditions of this character are abscesses or ulcers, or some are abscesses and others ulcers.

An alveolar abscess which has for its cause a dead pulp generally presents, at some period of its existence, that condition known as a dentigerous cyst or sac. When occurring upon the sides of a root, or in the bifurcation of roots of teeth, it may have the same cystlike character, but it oftener partakes of the character of an open or superficial ulcer. If the inflammatory process causes a separation of the pericementum from the cementum, but leaves the membrane more or less perfectly attached to the process, the sac-like condition will most likely for a time prevail. On the other hand, however, should the attachments first be broken between the process and the membrane, a cyst or sac is not likely to be formed, but, as is more or less frequently the case, the membrane will rapidly melt away and the lesion will present all the characteristics of an ulcerated surface. The physical differences therein are as follows: In the one case we have an open ulcer, with no specially-defined limit or line of action, while in the other we have a more or less closed ulcer, with a more definite demarkation between healthy and diseased tissue. So far as these physical aspects are concerned in the breaking-down of tissue, they probably amount to the same, all things else being equal; but their effects toward assisting or retarding the reparative process would seem to be at variance.

Now let us recur to the subject proper. You are aware that success in the estimation of some practitioners is not success in the opinion of others. The principal questions here involved are, by what standard do we measure success? and by what should it be measured? I anticipate the answer of some of my confrères by stating that the standard should be the length of time teeth so treated may be comfortably retained in the mouth. I also anticipate the answer of others by adding to the statement, "and be of service to the patient without detriment to surrounding tissue." My comment on such answers is that they simply imply varying degrees of success in conformity with the toleration of lesions present, by the endurance of the patient or integrity of the part involved. It is of common note that dentists speak of the cure of these cases as though it were absolutely perfect, and similar to the cure of a cut or wound in any external soft tissue. If this is true, i.e., if the lesion is healed in a

physiological manner, after that of healing in other tissues, it must be in one of two ways, viz., 1st, by a complete restoration of lost periosteum or process, or both, to and in their normal condition; or, 2d, by the formation of what may be termed false tissue, which, not being normally nutrified, is much more likely to be broken down.

Let us begin examination by taking for our first case a superior central incisor in which the dead pulp has been separated from the living tissues at the apex of the root by a physiological process. All practitioners will admit the comparative simplicity of such a lesion, and, with myself, acknowledge that if a perfect restoration of at least the periosteum involved can take place about the roots of any teeth so involved it certainly can in a case of the character above mentioned.

Prosecuting an examination into the physical, chemico-physical, and physiological conditions likely to be present in such a case necessarily exacts inquiry in several directions. First of all, the question as to whether the root-membrane in health has any connection with the vessels and tissue passing into the nerve-canal at the apex of the root must be settled. If it has not, then, in case of death of the pulp there is no break in its continuity at this point, save by contact and possible irritation of dead tissue of the pulp or other foreign substances. If a connection does herein exist, then death of the pulp breaks it, and conservative treatment will, in so far as this lesion is concerned, be successful in proportion to the degree of re-establishment of nutrient circulation at the point broken.

For the present, however, let us admit the truth of the former condition, viz., that there is no connection between these two tissues at or near the end of the root. It will be much easier for us to argue complete success from such a stand-point.

So much, then, being admitted, we have, in the case under consideration, a simple disconnection, at the apex of the root, of tissues once passing through to nutrify the dentine and other parts of the tooth. This break has been healed by a separation of the dead from the living tissue in a physiological manner. Now, this would seem to indicate complete success in an endeavor to save the tooth, and no doubt, if such a result be possible, it can be attained in this case, by a careful and thoughtful manipulator. But even here we necessarily contend with the possibility, aye, probability, of inorganic or disorganized organic irritants which may remain in contact with vitalized tissue at the end of the tooth after removal of the pulp. Aside from this, in the operation of filling the root-canal, we are

brought face to face with two difficulties, viz., that of securing a filling-material compatible with the healthy tissue whose border it should barely, yet actually, touch, and that of placing such material in such position that it would not impinge upon or be distant from this tissue. And yet these are not all of the influences operating against complete and lasting success in the conservation of such teeth. On the contrary, we must admit, even though there be (normally) no continuity of nutrition between dentine and cementum, that an animal substance like the dentine cannot, when deprived of vitalizing sustenance, remain continuously in juxtaposition with living tissue without affecting the integrity of such living tissue in a greater or less degree.

This case, of which I have endeavored to present the characteristics somewhat in detail, is, as you may readily see, one of those most favorable for treatment looking to successful results. Indeed, such teeth, presenting the conditions enumerated in the foregoing pages, are so often saved in usefulness to the patient for a number of years, without apparent detriment to or loss of surrounding tissue, that it would seem like making mountains out of molehills to even mention their characteristics. Nevertheless, the same underlying principles herein exist to modify success as are present to bar its probability in similar though more extensive lesions, the difference being only a matter of degree rather than character of conditions present.

Now, let us instance another case wherein exist similar diseased conditions, but presenting more extensive disruption of tissue. You have observed in practice (for I think such conditions common, even in a limited practice) that at times there is a denuding of the root-membrane about the immediate end of the root, consequent, at least, upon continued contact of dead, disintegrating, or suppurating tissue. To exemplify, we will take for example an inferior incisor or cuspid tooth, the shape of the root not exactly common to such teeth as a class, and yet very often met with, viz., one with the root flattened laterally, and thus comparatively thin from side to side; the dead pulp has been removed, the root is denuded of its proper covering for, say, an eighth of an inch from its foramen, and the remaining membrane thickened and irritated to the degree of cellproliferation for at least an eighth of an inch further toward the crown, and if the membrane is continuous from the point of separation from the root with the process round about the lesion it may be, and probably will be, inflamed to the extent of its separation.