[2]. “Archives of Dentistry,” Edited by Edwin Truman, vol. i., p. 169.
We have quoted the author of the foregoing at some length, as some of his conclusions upon this interesting experiment might seem antagonistic to our own. Thus, whilst we agree with him in concluding that a dead tooth becomes united to a living jaw by a certain amount of absorption of its fangs by osteoblasts, and a subsequent calcification of such tissue, we do not believe such process as fully accomplished or permanent. The valuable researches of Tomes and De Morgan show that during life a continual process of formation and absorption is taking place in bone, whilst the former has also pointed out that the process of absorption in the fangs of temporary teeth is one alternating between absorption and deposition, though in the end in favour of the former, i.e., that the osteoblasts which effect the absorption of the dentine often become calcified, but are again eventually decalcified and become active osteoclasts. What determines these bodies to act, so to speak, in a positive or a negative capacity would be most interesting to discover, and, in considering the subject, we can hardly overlook the views of Mr. Bridgman, who compares the process of bone formation and decalcification to what occurs in an electrolytic cell, where, by changing the direction of the current, the electrodes assume precisely opposite functions.
If, then, we could discover the conditions that would preserve the bone tissue, in connection with the dentine, from undergoing decalcification, we might, with every prospect of success, transplant dead teeth, but which, as at present carried out, invariably, we believe, eventually, suffer the fate of ivory pegs introduced into the extremities of bones in disunited fractures. Indeed, this result, although more slowly effected, appears nearly always to follow in those cases where the transplanted or replanted tooth has lost much of its alveolo-dental membrane; whether the excising of a portion of the fang, as advocated by Magitôt, will prove beneficial or otherwise, remains to be seen.
Porcelain teeth having indentations in their fangs have been suggested, first, we believe, by Mitscherlich,[[3]] and again by a recent writer in the Lancet. The former actually attempted two cases, and with the success we should have anticipated, for when after four or five weeks the caoutchouc splint which retained them in situ was removed they immediately followed the splint and fell out. “Ossification had not taken place; the entirely heterogeneous mass of stone had acted as a foreign body, produced granulation and suppuration, and so prevented union.”
[3]. Op. Cit.
In conclusion, we think enough has been stated to show that transplantation or replantation of living teeth, or at all events, of teeth having living alveolo-dental membrane may be exceptionally carried out with benefit to the patient; if the chances of permanent success be not very great the chances of injury are, we believe, small, and have been greatly exaggerated. No such case has come under our observation, but then in all we have witnessed, the transplanted or replanted tooth has never been ligatured or otherwise forcibly retained in its alveolus. We believe many of the cases of failure, as probably those also of bone exfoliation, arose from this procedure. A tooth, after either operation, although at the time perfectly adjusted to its proper position, becomes, after a day or two, elongated from its socket and less firm; the result of effusion into the alveolo-dental membrane and about the tooth; as this material becomes organized it forms, no doubt, the medium of union between the dental and alveolar portions of that membrane. At all events, after a week or so the tooth again recedes into its socket, and as it does so becomes firmer and less sensitive to pressure; if our view be correct, the employment of a ligature or forcible retention of the tooth can only be objectionable. A very different matter, however, will be the adjustment of a plate contrived so as to protect the transplanted or replanted tooth from violence or pressure until its attachment is ensured.
Mercurial Amalgams.
By M. G. CUNNINGHAM.
After twenty-five years of stubborn fight supporters of gold as a filling for decayed teeth accept the possibility of plastic material being in certain cases its superior; throughout this period I have been content to hold my peace and act entirely on my own judgment in the selection of material, as however, it seems to be the fact that a man who uses plastic filling without danger of being termed a “quack,” may speak, I would, through your kind agency, convey to brother Dentists my method of preparing metallic amalgams, which has saved me much trouble and my patients a large number of teeth.
In using amalgam, the first thing we ought to take into consideration is whether that which we are using and calling by that name is such, and I venture to say that in a very large number of cases it is no amalgam at all, but a concrete admixture of solid metals with liquid mercury. In the early days, when metallic precipitate of silver was employed, perfect amalgamation was not difficult to obtain, provided the precipitate had been in the first instance properly washed and carefully stoppered, the minute sub-division of the metal and absence of oxidation aiding largely to this result. The fillings of the present day are of a totally different character, coarse in grain, and of a nature to oxidize on even momentary contact with air, they become difficult to amalgamate with mercury, which, in itself, is a highly oxidizable metal, so that recourse is often had to a glass tube and violent agitation to produce that which is at best only a semblance of what it should be—a thoroughly homogeneous mass, that upon setting will retain a uniform texture and density proportionate to the constituents of which the fillings are composed. If, however, to the fillings and mercury be added a drop or less of sulphuric acid, either in the palm of the hand or mortar, it will be found that the metals will almost instantaneously amalgamate, whilst the oxides combining with the acid leave a residuum which, by its quantity, clearly shows what a very imperfect body could have been a so-called amalgam containing only a small portion of them. Washing in pure water at once removes all trace of acid, and a thoroughly reliable stopping can be at once produced from materials otherwise worse than useless.