The Dental Pulp—Its Office and Eccentricities. 
D. D. SMITH, D.D.S., M.D., Philadelphia. 
fRead before the American Dental Association, Asbury Park, N. ]., August 7, 1895.] 
SOME months ago there was a talk made before the Odontological 
Society of Pennsylvania, more from a practical than a scientific 
standpoint, on the office of the dental pulp. In the discussion 
that followed, a wish was expressed that the subject-matter of that 
talk might be embodied in a paper to be read before the American 
Dental Association. In accordance with that wish, the following has 
been gathered up for this occasion. 
It is hardly to be expected that there can be presented to a body 
of dentists of to-day anything specially new upon the office of the 
dental pulp. It is possible, however, in grouping well-known phe- 
nomena in an unaccustomed manner, to get a new view of an old 
subject, as we might take a picture wffiich had hung neglected for 
a long time because of an unsatisfactory light, and by re-hanging 
so change the light thrown upon it as to make it appear like a new 
picture. All we can hope to do at this time, in looking at the office 
of the dental pulp, is to present certain phenomena and facts in new 
groupings, and possibly to hang the old picture in a better light. It 
is not the purpose of this paper to study the etiology of the teeth, or 
to look minutely at the different formations uniting to make up a tooth, 
as the enamel, dentine, and cementum ; neither is it to treat of pulp- 
action in the original formation of these structures. The intention is 
rather to speak of the part the pulp plays in the economy of tooth 
solidification and of the deductions therefrom. It is well known that 
the different formations which make up the body of the tooth receive 
life and nourishment from two distinct sources,—the one from the 
pulp, and the other from the pericementum of the root. The full 
apprehension of this fact and the phenomena arising from it will 2 
greatly assist in establishing rational and substantial methods for the 
treatment and saving of teeth. The pulp is the central figure, the 
important factor of every tooth. To it is committed the care of the 
newly-erupted tooth, and its office work is to readjust, recalcify, con- 
solidate, strengthen, and sustain the enamel and dentine. Observers 
will doubtless agree with the proposition that, as a rule, the earlier a 
tooth is developed the more readily it yields to decay, and the more 
time taken for calcification before eruption the greater the resistance 
to decay manifested on the part of the tooth. The young tooth being 
frequently erupted into environments which are most unfavorable to 
its preservation, there begins at once a contention between the forces 
acting externally to destroy it and the vital forces of the pulp to pro- 
tect it from within ; and just in proportion as the pulp is able to do 
its office-work of nourishing, consolidating, and sustaining the 
exposed parts, will the crown at this period be protected from 
decay. Hence the emphasis that should be placed on keeping the 
pulps of young teeth in a condition of healthful activity. 
The law of use governing tooth consolidation, widely known and 
rigidly observed among patients, would probably do more to arrest 
the extensive decay now prevalent, between eight and fifteen years 
of age, than dentistry can ever accomplish by mechanical methods. 
In general terms, under fifteen years is the period of life when the 
foundation is laid for the character, good or bad, of the denture. 
Too much importance has been and is attached to inheritance as 
determining the character of the teeth. Standing in advance of 
inheritance, for children, is use of the teeth in mastication. Natural 
and healthful mastication will alone force that exercise of the teeth, 
required by the pulp and the peridentium ; and it is the true cleanser 
of the mouth and teeth. The more thorough this function, the less 
the necessity for dentifrices and brushes. 
The sixth-year or first permanent molar, erupting at an age when 
little thought or care is given to the teeth, is commonly the one over 
which the hardest battle for preservation is fought. The importance 
of saving these teeth has practically ceased to be a subject for discus- 
sion. The effort should be to save them, but with living pulps. 
Devitalization of the pulp at an early period of life carries with it 
a more or less rapid retrogressive change in the quality of tooth- 
material, and that without power to arrest it. Fillings may prolong 
the existence of the tooth as such, but with the arrest of vitality in 
the pulp there is cessation of all vital sustaining action, which hitherto 3 
assisted in its preservation ; and not only so, but the imperfectly calci- 
fied enamel and dentine already built into the tooth is now in contact 
with devitalized connective tissue, which, in the imperfectly consoli- 
dated tooth, becomes itself probably a source of disintegration and 
assists in its destruction. What has been said of the sixth-year molar 
may also be said of all other of the young permanent teeth. The pulp 
being to the erupted tooth, whether temporary or permanent, the 
only source of life, of sustenance, and of reforming changes, it is of 
the first importance that it be maintained in a condition of health ; 
and as this condition surely exists only when the pulp is protected 
in its own natural and proper covering, the dentine, all encroach- 
ments upon it through decay or manipulation should be carefully 
guarded. Its preservation in full activity means the deposition of new 
and better material, although parts of the crown may have been cut 
away or destroyed by decay. 
It has been said that the pulp is the only medium through which the 
enamel and dentine of an erupted tooth are compacted, consolidated, 
and changed into decay-resisting material. While thus defining pulp- 
action in this paper, the author would suggest that it seems more 
than probable that the future may discover that the action of the 
pulp is not confined to enamel and dentine alone, but that it extends 
a consolidating influence into the territory of the cementum, inciting 
in it changes whereby the true bone, which covers the root in the 
young tooth, is converted into a tissue resembling dentine more than 
cementum. 
• # 
Isolated instances of the action of the pulp, in re-arranging, de- 
positing, and solidifying the materials of the dentine and enamel of 
a young tooth, are in the minds of all men of experience and 
observation, but are we not prone to think of such instances as 
exceptional or as anomalous rather than as the true expressions 
of the law of pulp-action ? Are not our literature and the teachings 
of the past and present wanting, in that [a position of supreme 
importance is given to operations on the externals of the tooth, 
while overlooking the significant aid of that living factor within the 
walls of the pulp-cavity? And would it not be more in harmony 
with the true science of tooth-saving to emphasize the matter and the 
manner of pulp-protection in young life ? 
There is another question upon which dental literature and, so far 
as we know, dental teachings are silent. It is this : Does there ever 
come to a tooth a period when its pulp, with all this importance attach- 4 
ing to it in early life, can be dispensed with? It is the contention of 
this paper that a pulp which has maintained a healthful existence in a 
tooth to a period of perhaps twenty-five or thirty-five years of age 
has accomplished for that tooth all that it will or can do in the way of 
consolidating, strengthening, and solidifying its osseous structures. 
The maximum of density is reached, we may say, with full matur- 
ity. From this time the pulp forms a part of the tooth which can be 
readily dispensed with. It has done its work, often much better than 
it was feared it would. If it remains within the tooth, there is an 
unmistakable restriction of its function and a limiting of its activities, 
and sometimes there seems to be mischievous interference with the 
usefulness of the tooth. Having completed its office work of con- 
solidating the structures it was set specially to guard, it will some- 
times begin to build in upon itself, circumscribing its boundaries, or to 
deposit nodules of enamel or dentine, pulp-stones, sometimes ossify- 
ing the whole coronal portion, and sometimes even sending out notice 
of the mummifying of its entire substance by ejecting into the tubuli 
and the connective tissue of enamel and dentine an offensive color- 
ing matter, which baffles all efforts for its removal. But this is 
not all. Later in life do we not find teeth which have been decay- 
resisting for fifty or sixty years, seemingly changing in structure, 
assuming apparently a state of partial decalcification, returning again 
to conditions of childhood, as evidenced by their yielding more read- 
ily to decay ? Continuing on a little farther, a few years more per- 
haps, it is not uncommon to find that decay has become extensive 
throughout the remaining teeth. 
Along the gum-margin, particularly of the front teeth, where fill- 
ings have preserved the teeth for twenty years perhaps, around these 
fillings the teeth are beginning to break down,—and if we cut into 
these teeth now, we find a change in the structure, a change that is 
not imaginary ; it is real. The tooth has softened ; if refilled with 
gold, in a comparatively short time it begins to darken around the 
fillings. The very best that can be done with our metallics, they 
will no longer arrest decay as they had previously done. Now what 
has brought about this change? Is it not the living organism, the 
pulp that previously built and consolidated the osseous structures 
of the crown? The same pulp, after a period of practical inactivity, 
is again at work, but it is now transforming the compact material which 
it placed in that tooth into a condition wherein it yields much more 
readily to decay. Now, what are the practical deductions from this 5 
action of the pulp ? Suppose we take a tooth at the period of life 
when it is at its best, when the dentine and enamel are well and 
strongly consolidated, and destroy the pulp, what will be the result? 
One result certainly must follow. By no vital process can there be, 
later in life, any change of the compacted materials of the dentine 
and enamel into any better or poorer formations. As the tooth is 
when the pulp is destroyed, so it must remain, except as to those 
changes which take place through the gradual disintegration of the 
internal structures of all pulpless teeth. Have we injured the tooth 
in any material degree ? What is the prognosis of a tooth with pulp 
destroyed at the period of maximum consolidation? With present 
methods of treatment, who would venture the prediction that a pulp- 
less tooth would not continue in service to the end ? 
If, now, the pulp is so important at one period of life and of so little 
importance at another,—if it is, indeed, a builder in early life and 
may be a source of disintegration in old age,—shall we not revise 
our estimates of the value of the dental pulp ? and does it not open 
up possibilities for service, both in teaching and operating, in 
fields hitherto uncultivated ? 
One other point this paper would simply hint at, with a view of 
opening it up for investigation and discussion. It has been said that 
the future may demonstrate as a fact, what is yet but conjecture, that 
the action of the pulp in rebuilding the osseous structures of the tooth 
is not confined in its operations to dentine and enamel, but that it 
extends an influence more or less potent into the territory of the 
cementum, depriving it in some of its parts of much of the character- 
istics of bone-structure. If, now, this be so, there comes at least a 
suggestion respecting some of the unexplained manifestations of 
pyorrhea alveolaris. In this connection our first remark is : Pyor- 
rhea is seldom or never found in connection with young teeth ; it 
seems to be emphatically a disease of adult life, generally of middle 
life. Second : It is an affection not found in connection with soft 
teeth, nor in mouths with teeth much given to decay. So true is 
this, that in typical cases of pyorrhea it may be said there is no 
decay in the teeth. Third : It is never found in connection with 
devitalized teeth, where devitalization preceded the manifestation of 
the disease. In a mouth with extensive and uncontrollable pyorrhea 
it will be noted that the disease is confined to the strong, well-formed 
teeth, exempt from decay (not necessarily unfilled), but with living 
pulps. 6 
Our deductions are : If it should hereafter be found that the pulp 
sends a consolidating tendency or influence into the territory of the 
cementum, rendering it obnoxious to the pericementum, because of 
too great consolidation, there will be formed favorable conditions for 
the beginning of pyorrhea, and we shall find in it the probable solu- 
tion of the exemption of pulpless teeth from this disease,—why young 
teeth are not affected, and why pyorrhea is pre-eminently a disease 
associated with the hard, strong teeth of adult life. 
It is of vital importance that the cementum should be kept unim- 
paired and unchanged. The preservation of the pulp in a mature, 
well-calcified tooth is not a matter of so much concern, for whatever 
the conditions of the crown, it can be restored if the cemental struc- 
tures of the root are in normal condition. But a tooth which has lost 
its support, through absorption of process and withdrawal of peri- 
dentium, can never be restored to usefulness. 
From the foregoing we must conclude that the dental pulp is an 
organ of the greatest importance up to the period of full tooth-consoli- 
dation. After that, for a considerable period, as it would seem, it is 
of little service to the tooth, and, later in life, it may even become a 
source of injury and trouble. 
Of the gentlemen who have written of pyorrhea, no two seem to 
agree as to its etiology or methods of treatment. Age has not been 
regarded as a factor of any importance in connection with it. I do 
not remember that character or quality of the tooth-material has ever 
been considered as having any bearing on its origin or prognosis. It 
has been treated of as a disease of local or constitutional origin accord- 
ing to the views of the writer, the inference being that it may occur in 
the mouth of the child of twelve or fifteen years as in the adult of thirty 
to forty-five ; but from the foregoing it would seem that investiga- 
tions must extend to embrace age, tooth-structure, and pulp-action, 
as well as local irritants and constitutional vice, before it can be said 
that the origin of this troublesome concomitant of dental practice is 
satisfactorily defined.