CONCERNING COMBINED FILLINGS'. 
W. D. MILLER, M.D., D.D.S., Berlin. 
(Reprinted from the Dental Cosmos for July, 1892.)' 
Most practitioners of dentistry will, I think, readily indorse the 
statement that of the many materials used for filling teeth there is 
not one that does not fall far short of fulfilling the requirements of 
what might be styled the perfect or ideal filling-material. It is 
equally indisputable that the advantages or disadvantages of the 
various materials manifest themselves in various degrees in differeait 
classes of cavities, as well as often in different parts of one and the 
same cavity. 
For instance, in compound cavities gutta-percha serves its purpose 
excellently at the neck of the tooth, decreasing in efficiency rapidly 
as it is carried toward the grinding-surface ; while the cements, which 
may occasionally serve a good purpose at the grinding-surface, 
generally become worthless as we approach the neck of the tooth. 
These well-recognized facts not only suggest the idea of an eclectic 
practice, but have already given rise to the employment of various 
combinations of two or more materials for filling one and the same 
cavity. Furthermore, experiments in the laboratory, as well as 
experience in practice, have established the fact that for certain 
cases two materials thoroughly combined or mixed together, before 
introducing i7ito the cavity, may give a much better result than either 
of the ingredients used alone. 
We accordingly recognize two classes or categories of combined 
fillings,—those in which different parts of the same cavity are filled 
with different materials, and those in which the materials are so mixed 
that the filling has the same character throughout. The former 
might be designated as jointed fillings, the latter as mixed fillings. 
In the following lines I desire to call attention to some of the 
methods of combining different filling-materials which have been 
recommended, and in part have stood the test of practical applica- 
tion. 
The results thus far obtained have been sufficiently encouraging, 
I think, to merit more attention than has apparently as yet been 
bestowed upon them. Of the eighteen to twenty different combina- 
tions reported upon, some I shall only mention for the purpose of 
obtaining a general survey of the subject; others I shall discuss more 
at length as their importance may s’eenrm1 (ffirremrh:—-— \ i. Combinations in which a Layer of One Substance is introduced 
between the Bottom of the Cavity and the Filling Proper, as a Pro- 
tection to the Pulp. 
Recent communications upon this subject have added nothing new 
either in regard to materials or methods of manipulation, unless we 
except the experiments of Gilmer on the conductivity of different 
materials used in filling teeth (Dental Review, December, 1891). A 
completely reliable study of the comparative conductivity of different 
materials, as that of Gilmer appears to be, would often be of great 
service in determining what material should be used in filling teeth 
abnormally sensitive to changes of temperature. 
2. foint Fillings of Non-cohesive and Cohesive Gold. 
Many dentists still indorse the practice of combining non-cohesive 
and cohesive foils, with a view to utilizing the particular advantages 
claimed for each preparation in the same cavity. 
In large approximal cavities a pledget of non-cohesive gold is 
placed upon the cervical wall and followed up by cohesive gold ; or 
in case of the front teeth, the cervical and lingual walls may be 
covered with non-cohesive gold ; or, finally, all the walls of the 
cavity may be lined with it and only the central portion of the filling 
made of cohesive gold, which serves as a key to bind the whole 
together. 
The reasons given for this practice have been frequently pointed 
out, and must be familiar to everyone. From my own experience 
and observation I can only indorse the procedure, though in my 
practice tin-gold has largely taken the place of non-cohesive gold in 
such operations. 
The theoretical objection to this method, that the undercut becomes 
filled up with non-cohesive gold and that the cohesive gold does not 
have sufficient anchorage, I have not found to be an objection in 
practice. On the other hand, in saucer-shaped cavities where I 
have found it difficult to adapt cohesive gold, I have occasionally 
overcome the difficulty by making the bulk of the filling with non- 
cohesive and finishing with cohesive foil. 
3. foi7it Fillings of Tin and Gold. 
Spooner is reported to have used tin in combination with gold as 
much as fifty to sixty years ago, and in recent times it has been used 
quite extensively in pretty much the manner described under 2. A 
very thin layer of tin at the cervical margin was thought to adapt 
itself somewhat better than gold alone, and also, “in consequence of 
the oxidation of the tin,” to produce a filling perfectly water-tight at 
the neck of the tooth, a condition which can be claimed for but a 
small proportion of cohesive gold fillings in practice. The two 
materials unite in a short time, so that the objection to the combina- 
tion of cohesive and non-cohesive gold mentioned above does not 
hold here. 
I have no experience in this manner of using tin, though I am in 
almost constant use of tin-gold for the same purpose (as described 
under 5), and with most satisfactory results. 3 
4. Mixed Fillings of Tin and Gold. 
A thorough discussion of this combination would require more 
space for itself than I design to occupy for all the seventeen combina- 
tions to be considered in this article. The subject has, moreover, been 
repeatedly brought before the profession in late years, so that there 
is at present no particular call for an extended presentation of it, 
though I may return to it later. 
It has been gratifying to me personally to see that this combination 
has won some warm friends in America, although on the whole it has 
met with considerable adverse criticism, chiefly from those who have 
tried it but little or, often, not at all, and whose opinions therefore 
are naturally entitled to less consideration than tho.se of practitioners 
who have given the material a fair trial. Some of the remarks I have 
read concerning tin-gold do not quite come up to the standard set for 
unbiased scientific criticism. For example, Hungerford is credited 
with the statement ( Western De7ital Journal, May, 1891, p. 240) that 
non-adepts in the use of gold are the ones who favor the combina- 
tion. Any one inclined to make use of the same style of argument 
could only reply, Then why doesn’t H favor it? There is of 
course nothing to be gained by this mode of discussion. Besides, if 
the combination of tin and gold fulfilled only a need of the non-adept, 
what a blessing it would be to the profession and the community ! 
As a matter of fact, however, there is not a man in the dental pro- 
fession who is so proficient in the use of gold that he can afford to 
ignore materials which may not require for their successful manipula- 
tion quite as high a degree of skill as is required by gold. Finally, 
it is not difficult to find cases in which it requires much more skill to 
make a good filling of tin-gold or of non-cohesive gold than it does 
to pile up mountains of cohesive foil. 
ThepositiontakenbyOttolengui(DENTALCosMGS, February, 1892) 
appears to me to be also contrary to the experience of the great 
majority of the dental profession ; when he argues that there is no 
need of new filling-materials. Repeatedly we are confronted by cases 
where we are obliged to ask ourselves, not the question, Which is 
the perfect filling-material for this cavity ? but, Which has the fewest 
objectionable qualities ? 
The old song that failure of gold at the gingival margin is due to 
faulty manipulation does very well, but failure at the gingival margin 
continues to occur and will continue to occur, even in the hands of 
the most skillful and conscientious dentists, to say nothing of the 
dentist of average skill who makes up the great bulk of the dental 
profession. 
All honor to gold, although it is far from being a perfect filling- 
material ; but at the same time let us not attempt to discredit other 
materials, particularly when they have stood the test of over a quarter 
of a century, without having tested them with the same skill and 
patience and conscientiousness which we are called upon to cultivate 
in the use of gold. 
Having used both gold, and tin and gold, for fifteen years, I can 
only say that I meet almost daily with cavities which I can fill better 
and with far more ease to myself and to my patient with tin-gold than 
with gold alone ; and as there is no reason to suppose that I am differ- 
ent in this respect from everybody else, the inference is justified that 4 
others who would give the material a fair trial might find the same. 
Besides, this is the testimony of a great many practitioners who have 
become thoroughly acquainted with the materials. 
Naturally the manipulation of tin and gold is not learned in a day. 
The material must be inserted with care, and particularly those who 
have never learned the use of non-cohesive materials would probably 
encounter some difficulty. A badly condensed tin-gold filling will 
become brittle, sometimes powdery ; a properly condensed one never. 
I may mention in this connection also that the rolls of tin-gold should 
never be made with sweaty or moist fingers, or be allowed to lie in a 
damp place before using. They may in such case become stiff and 
difficult to manipulate. 
5, Joint Fillings of Tin-Gold and Gold. 
This is a combination in which tin is extensively used in connection 
with gold by the advocates of tin-gold as a filling-material. Large 
cavities of almost every character, particularly, however, compound 
approximal cavities, are filled one-third to two-thirds with tin-gold, 
and the operation completed with cohesive foil. It has a very decided 
advantage over amalgam used in this way, in that the gold unites 
perfectly with the tin-gold to form a solid filling. The operation may 
also be completed in one sitting, and the tin-gold has better pre- 
serving properties than amalgam. 
6. Joint Fillings of Non-cohesive Gold followed by Tin-Gold. 
A class of cavities which requires to be treated with great care is 
formed by approximal cavities in frail incisors and cuspids, in which 
the lingual wall is partly or completely destroyed. For those who use 
non-cohesive gold in such cases the operation may be lightened by 
covering the labial wall with non-cohesive gold and filling the cavity 
one-half to two-thirds full with it, finishing with tin-gold. In making 
these fillings with non-cohesive foil, I think most operators will agree 
with me that by far the most difficult part is the insertion of the last 
few pellets on the lingual wall, where we have not been able to obtain 
an undercut. 
One or two trials will convince anyone how much more readily this 
part of the operation may be performed with tin-gold. Of course, a 
filling of this kind has a gray color upon the lingual surface ; from the 
front, if seen at all, it appears as a gold filling. 
7. Joint Fillings of Amalgam or Cement over Gold. 
This combination applies only to those cases where a thin layer of 
gold is placed against a thin wall of enamel to prevent the cement or 
amalgam from showing through. If the surface of the wall is first 
given a thin coat of varnish, the gold, will adhere to it and keep in place 
while it is being fixed with the cement or amalgam. Where amalgam 
is used, Morrison (Archives of Dentistry, May, 1891) recommends 
gilded platinum, since it does not become amalgamated by the mercury. 
8. Joint Fillings of Amalgam and Gold. 
The practice of filling very large and difficult cavities one-third to 
two-thirds full with amalgam, and covering this with gold, has been 5 
carried out to a considerable extent, but reports as to the manner in 
which such fillings have stood the test of time are still wanting. Their 
chief advantage over all-amalgam fillings is their appearance, and the 
better preservation of the teeth at the grinding-surface; their chief 
advantage over all-gold fillings is their ease of insertion, and, prob- 
ably, in difficult cases, the better preservation of the tooth at the neck. 
One of its great disadvantages, which it possesses in common with 
many other joint fillings, lies in the fact that the two parts of the filling 
do not unite with each other. It is often also a serious drawback that 
the operation requires two sittings for its completion. 
I have seldom used it myself, because I consider the combination 
discussed under 5 preferable for most cases, since it gives a better 
adaptation of the filling at the neck of the tooth ; both parts of the 
filling unite firmly together, and the operation may be completed in 
one sitting. I have occasionally used the amalgam and gold to ad- 
vantage in distal cavities in the molars, in cavities involving the distal 
and buccal surfaces of bicuspids, filling the distal portion with amalgam 
and the buccal with gold. 
A method of making amalgam-gold fillings in one sitting was de- 
scribed by Clapp (Dental Cosmos, 1888, p. 870), and should be 
referred to in this connection. The principal features in Clapp’s pro- 
cess are : (1) The preparation of the cavity with square edges in the 
portion to be occupied by amalgam ; (2) the adjustment of a perfectly 
fitting matrix ; (3) the thorough condensation of the amalgam, which 
should be mixed dry ; (4) the use of Steurer’s plastic gold for be- 
ginning the gold portion of the filling. The first pieces are swallowed 
up, so to speak, by the amalgam, ‘ ‘ but by persevering the gold will 
soon assert itself and overpower the amalgam.” The filling may 
then be completed with any cohesive gold. The greatest care is 
necessary in every step of the operation. The meager reports which 
have appeared concerning the success of the Clapp operation in practice 
have been very favorable, and the article by Clapp (1. c.) should be 
referred to by all who are not converts to the pernicious doctrine that 
any tooth that is worth filling at all is worth filling with gold. 
9. Copper Amalgam and Alloy Amalgam. 
In order to take advantage of the saving properties of copper amal- 
gam at the cervical wall, and at the same time avoid the discoloration* 
of the tooth resulting from this material, as well as its tendency to 
wear away at the grinding-surface, it has been recommended to com- 
bine it with alloy amalgam. 
I have had no opportunity to examine the few fillings of this kind 
that I have made. W. H. Trueman (Dental Cosmos, 1889, p. 238) 
is reported to have stated that copper amalgam, while not discoloring 
the teeth when used alone, does have a tendency to do so when com- 
bined with gold or an alloy amalgam. He furthermore states that if 
the two amalgams are inserted at the same time, the alloy amalgam 
will not harden. 
Whitney, on the other hand (Ibid., 1889, p. 492), states that he is 
in the almost daily habit of covering copper amalgam with platinum 
* According to my experience, copper amalgam well packed and kept per- 
fectly free from moisture during the operation, very rarely discolors the tooth 
to any appreciable extent. 6 
and silver alloys, with the best results as far as hardening and appear- 
ance are concerned. Likewise Russel (International Dental Journal, 
1889, p. 654) writes, “ Some alloys will join very readily, as I have 
proved by filling one-half of a glass tube with alloy and the remainder 
with copper amalgam. When hard the tube was broken, and it was 
impossible to break them apart at the joint.” 
10. Cement or Amalgam over Gutta-percha. 
Gutta-percha is one of the best materials at our command in places 
not exposed to the action of mastication. It therefore performs good 
service at the cervical wall in approximal or compound approximal 
cavities ; cement, on the other hand, is altogether unreliable at the 
cervical wall, but holds comparatively well on the grinding-surface. 
The combination of the two materials consequently often gives a fill- 
ing somewhat better than gutta-percha alone, and far better than 
cement alone. 
For the last ten years I have very rarely made a filling of phosphate 
cement in cavities extending under the gum without protecting the 
neck of the tooth with gutta-percha, extending a thin layer of this 
material over the bottom of the cavity as a protection to the pulp 
where it is nearly exposed (Fig. 1). These fillings are, however, in 
Fig. 1. 
Fig. 2. 
Fig. 3. 
one respect far from satisfactory. The cement not only wears away 
rapidly, but also disintegrates at the joint with the gutta-percha, so 
that fillings of this kind soon have the appearance seen in Fig. 2. The 
food wedges in between the teeth and accumulates at the point c, ren- 
dering it very difficult to keep the place clean. Notwithstanding this 
shirking of duty on the part of the cement, the intrinsic saving capa- 
city of the gutta-percha protects the tooth from secondary decay. 
The result will be somewhat better when the gutta-percha is built up 
square, as in Fig. 3, though in this case it does not afford the same 
protection to the pulp. In like manner amalgam may be used as a 
capping for gutta-percha, and where the walls of the cavity are suffi- 
ciently strong, it gives a decidedly better result than cement. 
In both cases a hard variety of gutta-percha should be used, I have 
found soft varieties to wash out, thereby rendering the result seen at 
c (Fig. 2) still more pronounced. 
xi. Gutta-percha or Cement protected by a Thin Gold Plate. 
This combination was occasionally used formerly in large cavities 
pn the grinding-surface. The plate, gut to fit the opening of the cay- ity as accurately as possible, has one or two short pins soldered to it 
at right angles to the surface, and is simply pressed upon the cement 
while yet soft, being retained by the pins as well as by the adhesion 
to the surface of the plate, which should be roughened. In case of 
gutta-percha fillings, the plate, of course, may be warmed before press- 
ing into place. 
12. Amalgam retained by Cement. 
On account of the tendency of amalgam fillings (manifested, it is 
true, to very different degrees in different preparations) to contract or 
draw away from the walls after insertion, retaining points or undercuts 
are imperative in all cavities which do not otherwise have a retaining 
form.* Cases are, however, constantly occurring in which it would 
be of the greatest benefit, for reasons well known to every practitioner, 
if the necessity of making retaining points or undercuts could be 
avoided. For such cases it has been recommended, and to some ex- 
tent practiced, to cover the bottom of the cavity with phosphate 
cement and to pack the amalgam immediately over it while the cement 
is still soft. The cement should be of a variety which possesses the 
greatest adhesive properties (they vary much in this respect), and 
should be mixed rather thin. It is well to press or prick the first 
portion of amalgam into the cement with a deeply serrated instrument. 
Experience with this method has been limited as yet, but there is 
no question in my mind that it is worthy of trial. A few experiments 
made out of the mouth will soon convince one that the amalgam 
firmly adheres to the cement. 
13. Gold retained by Cement, 
In a manner similar to that just described cement may serve to 
retain or help to retain gold fillings in shallow cavities. The bottom 
of the cavity is covered with cement in a soft condition, one or more 
pellets or pledgets of cohesive gold pressed into it, care being taken 
that the upper surface of the gold does not become in any way con- 
taminated by the cement. As soon as the latter is thoroughly hard- 
ened, the operation of building on the gold may be proceeded with. 
Naturally a very adhesive, quick-setting cement is desirable. 
A somewhat different method of obtaining the same result has been 
recommended by Oltramare (communication faite an Congres odonto- 
log’que suisse, le 4 Octobre, 1890). 
He uses a gold cake, prepared out of the mouth, which he presses 
upon the cement already partially hardened, at the same time warm- 
ing the gold by means of a heated burnisher or by blasts of warm air. 
The cake is easily pressed into the cement, which has been resoftened 
by the heat and adheres firmly, while the cement quickly sets again 
and permits the operation to be proceeded with almost immediately. 
Oltramare prepares the gold cake by condensing a number of gold 
cylinders or pellets upon the surface of a serrated steel plate, holding 
the gold with one instrument and condensing it with another. The 
cake must be adapted to the cavity in size and form, and being serrated 
on the under side it adheres very firmly to the cement if properly ad- 
justed. Experiments out of the mouth give very promising results. 
* An exception may be made in favor of some copper amalgams, 8 
14- The Combination of Amalgam and Cement 
has in late years received considerable attention both in Europe and 
America. 
The first reference to the method which I have met with in dental 
literature is found in a communication by Tileston to the Dental 
Review of August, 1888. In Germany Sachs has done much to intro- 
duce the operation ; also Klemich (_Journal fur Zahnheilkunde, 1890, 
No. 11) writes that he has used the mixture for many years. 
I have already described the method of mixing the materials, in 
the Dental Cosmos for January, 1891, p. 21, and have nothing 
essential to add to what has been said there. The cement should be 
of an adhesive (sticky) variety, and must be thoroughly incorporated 
with the amalgam, while the amalgam must be of the best quality 
and contain enough mercury to effect a complete amalgamation. In- 
corporated in a powdery condition, it may do more harm than good. 
It is claimed that the combination does not contract on setting, and 
experience seems to confirm the claim. It appears to withstand both 
mechanical and chemical action much better than cement, and is a 
poorer conductor than amalgam ; it is as easily inserted as cement, 
and is nearly as adhesive. It certainly deserves a trial. I use it 
almost altogether where I otherwise might be tempted or compelled 
to use cement, and have been very well pleased with the results. I 
do not, however, wish to be understood as unreservedly recommend- 
ing the combination ; experience has not yet been extended enough 
for that. In some cases I have found it to wear away at the grinding- 
surface. Its color is against it in some cases, though I have not found 
this an objection except for the upper front teeth. It may be varied 
almost at will, since it depends upon the color of the cement used 
and the proportion and quality of the amalgam, as well as upon the 
particular preparation of amalgam used. 
In a case of extensive erosion of all the front teeth, where the patient 
would not think of having gold and cement had proved almost useless, 
I obtained results with cement and amalgam with which both the 
patient and myself were better pleased as to appearance than with 
cement, and which have already outlasted two cement fillings and still 
show but little sign of wear. I should say, however, that in this case 
the teeth were considerably darker than the average. 
I have occasionally also found cement-amalgam very convenient 
for setting pivot teeth in forlorn cases, and must say that it has worked 
far better than cement alone. I should think it would be excellent 
for setting Logan crowns, but have no experience in that direction. 
15. Combination of Gutta-percha with Alloy Filings, Tin, etc. 
Repeated attempts have been made to increase the hardness and 
resistance of gutta-percha by incorporating various inorganic sub- 
stances into it. The world-renowned Hill’s stopping is one of the 
results of these attempts. More recently it has been sought to attain 
the same end by softening the surface of the gutta-percha filling with 
chloroform (Butler), or with eucalyptol, or by heat, and then working 
filings of alloy into the superficial layers (Line). Finally, the softened 
gutta-percha has been kneaded together with metal filings before 
introducing it into the cavity, so that not only the outer layers but 9 
the whole filling was permeated with the filings. Up to the present, 
however, no particular advantage seems to have been gained by these 
experiments. 
In the February number of the Dental Cosmos, Line recom- 
mends a new method of combining tin with gutta-percha in which the 
filling is so made as to consist of alternate layers of gutta-percha and 
Fig. 4. 
Fig. 5. 
Fig. 6. 
tin, so placed that the layers are parallel with the direction of the 
force in mastication. Fillings so made are observed to wear away 
much more slowly than gutta-percha fillings. (See Figs. 4-6, also 
consult original article, Dental Cosmos, 1892, p. 133.) 
16. Combinations of Cement with Alloy Filings or with Pulverized 
Porcelain. 
Parker (Ibid., 1890, p. 30) recommends very highly “zinc-phos- 
phate and alloy filings mixed and prepared for filling as ordinary 
phosphate.” Having used it for five years, he finds it far supe- 
rior to any cement. He uses an alloy of silver, tin, and a little 
platinum. Alloys containing much zinc or copper should not be used. 
The cement should be the dento-plastique of The S. S. White 
Company, or something like it. “It has the qualities of any cement; 
secondly, it always presents a metallic surface, so that it is worn down 
very slowly by mastication ; thirdly, as to conductivity it is better 
than either of the strictly metallic or cement preparations” (Parker, 
1. c.). Howe (Ibid., 1890, p. 33) likewise speaks well of the mixture. 
Perry (Ibid., 1890, p. 32) has occasionally used pulverized artificial 
teeth mixed with the phosphate, sometimes with astonishingly good 
results, sometimes not. I have tested the method a few times, and 
suggested it in the Oesterreichisch- Ungarische Vierteljahrsschrift, 
January, 1887, but was not sufficiently encouraged by the results to 
continue the experiments. 
17. Combination of Glass or Porcelain with Amalgam or Gold. 
Cases are frequently to be met with in which caries, beginning on 
the approximal surface of the upper incisors or cuspids, has 
destroyed a portion of the labial wall. Fillings of gold are naturally 
more or less conspicuous ; cement is not much better, besides being 
very impermanent; porcelain or glass fillings cannot be inserted for 
want of space. For these cases Dali, of Glasgow, first recommended, I 
believe, to fill the lingual or approximal portion of such cavities with 
gold or amalgam, then to properly shape the labial or visible portion 
and insert a porcelain filling. 
A case in which I was able to employ this combination to advantage 
was that of a superior first bicuspid, of which only a portion of the 
lingual cusp was still standing. The patient decidedly objected to a crown as being artificial, and demanded something which would not 
be conspicuous by its color. I built up the crown with cement, 
which only partially satisfied her demands, and in a few months was 
of course very much worn down. I then restored the crown with 
amalgam, and when it had set, on the following day, prepared in that 
part of the filling which was visible from the front a box-shaped cavity 
with rounded corners, took an impression with No. 30 platinum gold, 
melted a glass filling, and set it in with phosphate cement. No one, 
except perhaps a dentist, conversing with the lady, would suspect 
that the tooth was not perfectly sound. The operation was performed 
only five months ago, so that not much can as yet be said as to its 
durability. 
Besides the combinations already referred to, various others have 
been proposed or recommended, such as inlays of vulcanized rubber, 
combinations of Robinson’s fibrous foil with gold, using mercury to 
establish the union between the two (McLeod, Dental Cosmos, 
1890, p. 209). Furthermore, the use of two metals in combination 
for root-fillings, in order to bring about an antiseptic action through 
the electric currents thus established, or, what seems to me to be of 
still more doubtful utility, the use of a wire of combination metal of 
tin, silver, and gold in the treatment of pulpless teeth to obtain an 
electric stimulus.