Percival deserves the gratitude of his professional brethren for
directing their observation to the point. Every practitioner, however,
has met with instances in which the molars were implicated. There are
two forms of disease to which these teeth are liable; caries, or decay,
and a loss of vitality, or death. The death of a tooth has not hitherto
been observed upon by veterinary authors, but it is not rare. The causes
which may give rise to it cannot be accurately stated, though they may
be conjectured. The vessels that nurture the fang and ramify through the
pulp, are small and delicate; the alveolar cavities are thin, some of
them in the upper jaw being not thicker in parts of their walls than
brown paper. The force of the masticatory muscles is very great, and if
any hard substance be taken between the teeth, it is easy to imagine
that the minute arteries of the fang should thereby be ruptured. The
effect produced upon the pulp, and the transient agony occasioned by
biting a piece of hard crust, are familiar to every human being; nor can
we suppose that the horse's teeth, especially when the greater strength
of its muscles is duly considered, are not liable to similar and
proportionably greater injury. There may be no history to such a case,
no record of the date when the occurrence took place; for the horse is
not always watched during the time of its feeding, nor were it watched,
is it possible that the groom would attribute the sudden exhibition of
pain to the right cause. The primary effect is therefore misinterpreted
or unnoticed; but after a time it is remarked that the creature is
longer than its companions emptying the manger; then it begins to quid
its hay,--that is, the hay is taken into the mouth partially masticated
and formed into a pellet or round mass; but instead of being swallowed,
the prepared morsel is allowed to fall from the mouth. Should no advice
be taken, the horse becomes bad in its coat, and loses flesh. No amount
of corn, or extra grooming, will restore it to condition; medicines may
be administered with no better effect. The disease is strictly local in
its nature, and the constitutional symptoms are only sympathetic. Should
the affection still be suffered to proceed unchecked, the animal is
continually moving its lips; either it is restless in the stable, or
leans the head against the manger, and neglecting the food which is
before it, remains dull and quiet, the eyes half closed, and the
breathing quickened. A dose of medicine seems to do it some temporary
good, but the purgation has hardly ceased before the symptoms reappear;
saliva runs from the mouth, and the food in the manger is rendered
sloppy, almost like to a mash, before it is eaten; the bones of the face
at last swell; the breath becomes fetid; and a thick offensive purulent
discharge issues from one of the nostrils. That discharge is not
continuous; sometimes it will cease for days, and the proprietor
congratulates himself that the horse is getting well; the fetor,
however, remains, and after a time it breaks forth again with redoubled
vigour. The animal becomes daily worse, and would linger on, but the
patience of the owner is exhausted; the knacker is employed to cut short
the hopeless trouble and expense, and then a hasty examination is made
for the cause of all this mischief. Such is a condensed description of
the customary incidents, in the order in which they ensue; but of course
the intelligent reader is aware that the symptoms of disease cannot be
mapped down, as though they were results obtained from inorganic matter.
Such symptoms always more or less vary, though upon the whole they
present sufficient similarity to enable them, in every case, to be
interpreted; and hence the value of practical experience, which enables
the party possessing it to recognise a fact, when not fully declared.
The writer cannot, to the like extent, communicate instruction; he must
condense his remarks, and be content to speak a general truth; for if he
descends to particulars he becomes tedious, and that which he would
teach is disregarded. Of course the symptoms vary: all may not be
present, yet one or more will lead the practised mind to the seat of
injury. The history, however, which has been recorded, supposes the dead
tooth to be located in the upper jaw: should it be situated in the lower
jaw, some difference will be presented in the effect; for then the
injury is not so serious. The discharge from the nostrils does not
ensue, but the inferior maxillary bone enlarges, and the breath becomes
offensive. The swelling of the bone takes place immediately under the
tooth which has ceased to be a part of the living frame; and at this
point also an abscess forms; this bursts, and discharges an unhealthy
matter: unlike ordinary abscesses, however, which, when they have thrown
out their contents, close, this, notwithstanding that the orifice is
dependent, exhibits no disposition to heal up: a thin stinking liquid
continuously issues from the opening, which becomes hard around its
edges, and the hair about which sticks out, looking coarse and ragged.
Such outward and visible signs are hardly to be misunderstood; and
attention being directed to the mouth, the examination of the teeth
will confirm them. From one jaw will be felt a molar projecting far
above the level of the rest, and in a like degree will the opposing
tooth in the other jaw be found depressed--worn down actually to the
gum. All is now clear; and the question is, what shall be done? In the
first place the condition of the mouth has certainly deranged the
digestive organs, and, where there is room for choice, no operation,
however simple or apparently safe, should be undertaken while the
stomach is out of order. The seat of the disease is known, but the
general health is first attended to; and when that has been in some
measure re-established, the great object of the surgeon is fit to be
accomplished. The question is, which of the teeth are to be interfered
with? One is diseased or dead, and there can be no doubt that the
diseased tooth should be removed. That which is unnaturally long,
obviously indicates that its power of growth is retained; and though
hypertrophy is an abnormal action, teeth are not parts liable to that
species of affection. The one which by its growth indicates vitality,
therefore displays no symptom of disease; but the tooth that is reduced
to the level of the gums, tells us that its power of self-preservation
has ceased, and that its vitality is gone. If that tooth be felt, it
will, in the majority of instances, be found loose, and therefore it can
be easily extracted: the operation, however, is not then ended. Should
the affected organ have occupied the upper jaw, a quantity of pus may
flow freely into the mouth on its extraction, but more frequently such
will not be the case: nevertheless, the discharge from the nostril,
(should the case have been of long standing,) together with the softened
and swollen condition of the facial bones, may convince the attendant
that matter is locked up in the maxillary sinuses. Some writers speak of
the antrum as the part most seriously affected; but I cannot find any
thing corresponding to the antrum in the horse's head. That animal has
no development of this description, and therefore it only shows
ignorance to operate with a special view to opening an imaginary cavity.
The maxillary sinuses are spacious cells, and freely communicate with
the frontal sinuses, which are also large. These facial sinuses have but
a limited and kind of valvular opening into the nasal chambers, and if
pus is allowed to remain within them there is little hope of cure:
therefore a means must be found for its escape. To this end the finger
is employed to probe the alveolar cavity, whence the tooth was taken,
and it will probably prove to be of no great depth. An instrument
constructed for the purpose is now used, and with it a hole is made
through the walls of the alveolar, directly into the maxillary
sinus--his knowledge of anatomy teaching the operator so to direct his
hand that none of the important nerves and vessels, which ramify through
the parts he is penetrating into, may be injured. On the withdrawal of
the instrument, pus will mostly follow, but not gush forth as from an
ordinary abscess. A dependent orifice has now been established, and if
the case is not a severe one, that may be sufficient: if, however, the
disease is aggravated, it will be necessary to trepline the frontal and
perhaps the maxillary bone, leaving in each a free space, from which a
circular piece has been removed. Through the superior opening, warm
water is injected; but if the stench be very offensive, a weak solution
of chloride of lime or of creosote may be employed, and must be daily
repeated. None of the coarse applications which some ignorant persons
recommend, ought to be used. A strong solution of the sulphate of
copper or of zinc, by coming in contact with a large surface of
granulating mucous membrane, can hardly be expected to allay its
irritability, or dispose it to take on a healthy action; and a seton,
forced barbarously through the orifices made with the trephine, can only
exist as a foreign agent, keeping up the action which the surgeon is
desirous should terminate. Gentle means are, in every sense, the ones to
be adopted. Mild tepid injections are to be employed, with the intention
to wash out the accumulated pus, allay the inflammation that caused it
to be secreted, and correct the diseased tendency of the part. All
stronger agents are barbarous; and I have witnessed animals rendered
dangerously vicious by their employment. When, however, the acute stage
has past; when the inflamed and secreting surface has lost its activity,
not unfrequently succeeds a dull, lethargic state, which the mild
treatment, hitherto advised, will not touch: now it is that stimulating
injections are beneficial; and however much reason there was in the
first instance to denounce their employment, they are now indicated by
the soundest principles of scientific practice. Even at this time,
however, they must not be pushed too far. The constitution should be
stimulated, that their effect may be aided, and their continuance
necessitated for the shortest possible period. The sulphate of copper or
of zinc; the acetate of copper or of zinc; the chloride of zinc or of
lime; the nitrate of silver or of mercury; the black or yellow wash, in
strength proportioned to the symptoms, may here be of service. It is
well, however, to remember that these agents soon lose the efficacy, and
the greatest benefit, therefore, is obtained when they are occasionally
changed on the first sign of their potency decreasing. Still injections
alone cannot be expected to effect a restoration, and, therefore,
topical measures must be combined with constitutional treatment. A
course of mercury may be tried, or some of the many agents, which, like
balsams, peppers, and essential oils, act on the mucous system, can be
administered,--never, however, relying upon any one medicine for too
long a period; but, as in the previous case of injections, changing it
wherever the drug appears either to have no effect, or to have lost its
power over the system. By such treatment, actively employed and combined
with a proper attention to exercise and diet, the case must be
aggravated indeed which is beyond relief. The cure, however, we must not
expect to be quick; but it will generally in the end be realized.
Perseverance may be required, but barbarity will not hasten success. I
object to many of the practices which the veterinary professors of the
London College inculcate to their pupils; because those practices, in my
opinion, being based on false principles, are needlessly severe. Of the
potent solutions habitually employed at the St. Pancras School, I have
spoken; but there is another practice to which I have not alluded: corks
are forcibly thrust into the holes made by the trephine, under the
notion that by such means the opening can be kept free, and the wound
uncorked and corked up like the mouth of a bottle. Mr. Percival has
spared me the trouble of exposing the folly of the idea, and the
inutility of the practice. That gentleman tried the notable experiment,
and found that the cork in no degree delayed the consequence it was
employed to retard. The presence of a foreign body thrust into immediate
connexion with a diseased surface, and violently there retained, must
cause excruciating agony--promote serious irritation--and might lead to
the worst possible results. The ignorance should indeed be gross, which
could conjecture such a vulgar resort was capable of inducing the
slightest benefit. Equally objectionable is the custom recommended by
the veterinary professors, of shutting an animal up in a close stable,
and causing it to inhale the fumes of chlorine gas. Chlorine is an
irritant to mucous membranes. If the nasal cavities were the seat of the
disease, the passage of the air being rapid through these channels, and
retained for a comparatively long period in the bronchia, the supposed
remedy would be far more likely to affect the lungs, than to act
immediately on the part which it was intended to benefit. In
respiration, however, it is not probable that even during health, any
large quantity of air enters the sinuses, which, in these cases, are the
seats of the disease; and when those cavities are blocked up by an
abnormal secretion, none could possibly gain admittance to them.
Chlorine, therefore, obviously is inoperative in the direction where its
remedial agency is desired to act; and it does some injury. It violently
affects the animal which requires to be soothed; causes it to endure
much inconvenience and even suffering; produces quickened respiration
with violent cough, and may be reasonably supposed to lay the foundation
of subsequent disease. The advantages of its employment have not been
demonstrated, but the results of practice rather show it to be
injurious. By the members of the veterinary profession it is not
generally used: gentler measures are of greater importance, and these
ought, only under very peculiar circumstances, to be abandoned. There,
however, yet remains to be described, the mode of proceeding when the
diseased tooth is seated in the lower jaw. In that case, a sinus or
canal, discharging an unhealthy matter, is present. No treatment will
cause that sinus to close, while the diseased tooth is retained; and
until its removal is effected, all applications designed for that end
are thrown away. After the tooth has been extracted, a solution of
sulphate of zinc may, with advantage, be daily injected, and
constitutional measures at the same time adopted, till an altered action
has been called forth, when the annoyance will quickly cease. The
enlarged bone will, however, remain; and, in the majority of cases, it
may be best no further to interfere with it, than by the external
application of such agents as are likely to promote absorption. In such
cases, however, no means are very speedily beneficial, and time must be
given for their operation: but should the deformity be great, the firing
iron may be employed to cause exfoliation of the part. Yet as in the
removal of one blemish, it is not justifiable to create another, the
violent agent must be applied after a particular manner. The integument
should be first divided, and the edges of the incision drawn asunder, so
as to expose the bone, which alone should be touched with the cautery.
By this simple expedient the osseous structure will be destroyed; and as
such structure is not highly sensitive, the suffering of the animal will
be slight, while after exfoliation has taken place, the trivial cicatrix
will be concealed by the hair. When caries is present, the symptoms do
not materially differ from those described as indicating the death of a
tooth. The disease may commence at any part of the fang or crown; but
the structure which it generally first involves in the horse, is the
crusta petrosa: for however far the caries had proceeded, I have usually
recognised it working from this substance into the ivory. The crusta
petrosa is the least osseous, and most vascular of all the structures
that enter the composition of the tooth. In proportion to the
vascularity, may be estimated the disposition to assume disease; and
when it is further remembered that the crusta petrosa being the
external, is the most exposed portion of the tooth, and that any
wrenching action, or other violence, would first affect this part, the
dullest comprehension will perceive why the crusta petrosa is likely to
be the primary seat of caries. Enamel is not subject to caries, nor is
it otherwise involved than by being deprived of its supports, and
chemically acted upon by the decomposed matters with which it is in
contact. The ivory, however, may, in exceptionable cases, be the
original seat of the affection; and when decay has commenced, this part
of the tooth is speedily diseased. When caries begins, there is only
partial death of the tooth; but the portions which retain their vitality
and are becoming affected, cause excruciating fits of agony. Before
anything can be perceived by manipulating the molars, the animal may
exhibit frequent slight fits of illness, being occasionally dull--off
its feed--sluggish at its work--soon fatigued--resting the head on the
manger, and displaying symptoms of transient attacks of fever. On other
days the animal is lively; eats well, looks well, and works well, and is
all the owner could desire. Something is evidently wrong, but as yet all
is doubt: then the hay is quidded and another examination of the molars
is made, when there may be detected a little roughness on some part of
one of those teeth, and the mystery is explained. There may be no, or a
very slight increased growth of the molar, which, in the opposing jaw,
corresponds to that which is evidently carious. The carious tooth may be
firmly implanted; and yet, notwithstanding the firm manner in which it
is fixed in the jaw, no time ought to be lost in its removal. The
operation may occupy some time, and should be conducted with proper
caution if the horse be young; and I have by me a molar taken from the
jaw of a colt that was rising four, in which the crusta petrosa was
diseased. A wood-cut representing that tooth, is inserted at page 29;
and the darker spot indicates the place where decay had commenced.
During youth the fangs of the molars are of great length, consequently,
any violence would be likely to do injury to the thin plates of the
alveolar cavity. In old animals the fangs being shorter, greater speed
may be allowable; but in every instance where the tooth is firm,
judgment must be exercised. Supposing the horse to be young, the
following method will be found to answer:--The precise position of the
tooth having been ascertained, and the animal cast, traction, with a
proper instrument, is made in the right direction. In the first attempt
the force is not designed to extract the tooth; if it can be perceptibly
moved or raised upward, so that the nerves and arteries of the pulp may
be broken or ruptured, a great point has been gained, and the molar
should be no further drawn in the first instance. The instrument should
be then loosened, and another hold having been taken, a renewed effort
should be made, when a little additional way may be gained. After this,
a further hold should be taken, and thus adapting the grasp of the
instrument to each pull, and proceeding gradually, the molar may be
extracted. The operator, however, must not, in every instance,
anticipate that he will be thus successful. The tooth may be perceptibly
moved, but after this it may resist all subsequent attempts. The surgeon
will become aware that only great force could accomplish his wishes,
and he will therefore reflect whether the employment of the necessary
violence might not fracture the jaw as well as extract the tooth.
Something has been gained by rupturing the arteries and nerves. The pain
and course of the disease has, in a degree, been checked. The molar is
no longer a part of the body, but a foreign substance; and Nature, if
left alone, will proceed in her own way to eject it. The course,
however, that Nature, if unaided, would pursue, might be too slow to
prevent evil consequences. The operator, therefore, discontinues his
attempts for the present; and though some foolish persons will think
slightly of him, for not at once doing the thing he desired to
accomplish, he orders the animal to be let up, and led back into the
stable. Many a proprietor has been so displeased by this, that he has
thereupon sought other advice; and the next operator has pleasingly
surprised him, by extracting, with ease, the tooth which the first
wisely forbore to wrench out of the jaw. The fact is, that the time
which intervened had made a material change; the molar had become loose,
and he who properly refused in the first instance to drag it forth,
would now, had he been permitted, have taken it out without difficulty.
Indeed in every case where the operator is made conscious of great
opposition from natural causes, it is better to cease all attempts for
the present--to wait for a week or two, and then renew the trial; and
even make a third effort, after a like pause, rather than by
unjustifiable violence hazard an accident, perhaps more fatal in its
consequences than the evil which it was desired should be removed. The
course of the malady allows the surgeon to exercise his patience,
without effort; and even if danger threatened, his principles teach him
that force is never justifiable. Gentle, resolute, and collected, must
such a person be at all times: the violence he seems to employ is but
the proper application of his art, and the speed he appears to make is
but the graceful use of the time and means at his command. Often does he
to the ignorant appear to be idle, when he is only anxiously waiting for
the proper time to commence his operations; and frequently is he accused
of precipitation, when he knows that activity alone can crown his
efforts with success. Let there then be no authority exercised over him
whose painful duty it is to deal with disease. The means at his command
are confessedly small, the end to be accomplished is acknowledged to be
great. The labour is harrassing, the result is dubious, and any
interference can but deteriorate from the success of the issue. A wise
person will therefore see often, observe much, and think long, before he
presumes to suggest anything to a medical practitioner, and never will a
command issue from his mouth. All, however, within and about the stable,
are, for the most part, in their own conceits, qualified to cure the
horse; and curious are the suggestions obtrusively volunteered, and the
judgments pronounced during every operation. Frequently, indeed, is the
animal sacrificed by the ignorance of its anxious attendants, who, in
their zeal, will often, out of their scanty wages, purchase injurious
nostrums, notwithstanding a member of the Royal College of Veterinary
Surgeons may be in regular attendance. Happily for the teeth, no
specifics are yet declared, and the groom is therefore unwillingly
obliged to be idle. The owner should also be passive, seeing that which
is ordered is administered, and taking care that no charms are employed.
When the tooth that was carious is in the early stage extracted, the
animal is by a little constitutional treatment, afterwards quickly
restored, but from time to time will require attention; for the teeth
that have once been operated on, will, at intervals, ever after during
the life of the horse, need the hand of the surgeon. If caries, however,
is neglected, and proceeds to the last stage, cure is all but hopeless.
During the death of a tooth, the symptoms are continuous. In caries,
there are intermissions, seasons of uncertain duration, during which the
horse appears to be free from suffering; but the effects, if not so
rapid in their development, are more frequently fatal in their
termination. When a tooth has lost its vitality, it becomes a foreign
body, which Nature, in time, will cast out. The retention irritates the
surrounding structures, but the irritation may in part be regarded as a
restorative process. When caries takes place, a portion only dies, but
that portion has all the injurious effect which could be attributed to
the former case, and even more, for the remaining vitality in the
unaffected part of the tooth, prevents Nature from resorting to that
process by which she would otherwise cast off the dead matter. In
consequence of this, a foreign substance is retained for a longer
period, and at the same time disease is progressing. Here, therefore,
is an additional cause at work, and hence the excess of effect. The
arteries which nourish the pulp, and the crusta petrosa, proceed from
the vessels which nurture the bone, and supply the mucous membrane of
the sinuses with the means of secretion. The same, likewise, may be
stated of the nerves going to the tooth, and though through these last
the constitution is affected, it is mainly through the agency of the
blood vessels, that the sinuses become diseased. Hence the necessity for
decision, and the need of judgment, in the application of the remedy. To
enforce the foregoing remarks, and convey to the reader a slight idea of
the consequences which ensue from a carious tooth, the accompanying
wood-cut is introduced. The specimen selected for illustration, does not
exhibit a rare or extraordinary proof of the results of this species of
disease.
[Illustration]
The head of a horse has been divided below the orbits, and a back view
of the facial portion is here shown, the spectator being supposed to
look into the cavities, which have been thereby exposed. _a_ indicates
the molar teeth on that side which was not the seat of disease, and they
are of the natural length and obliquity. _b_ denotes the teeth on that
side where the disease was seated, and shows them to be not only
unusually slanting on their grinding surfaces or tables, but also of
considerable length. It was the last tooth on this side which was
carious, and the shape of the molars has been occasioned by the animal
during its life, being unable, because of pain, to freely use these
organs in chewing its food. The effort to avoid any stress upon the
diseased tooth, has caused those on the same side to suffer only partial
attrition; hence they have become long and slanting, presenting sharp
pointed edges, which lacerated the lining membrane of the mouth. The
incisors, a distant view of which is given, likewise display the
consequence of the animal's mode of feeding. Turning from the teeth to
the exposed cavities above them, it will be seen that these are not
symmetrical, or of equal dimensions, which in the head of a healthy
subject, they undoubtedly ought to be. Those on the diseased side are
not only the largest, but differently formed. The alteration has
resulted from the inflammation and accumulation of pus within them.
Something besides pus, however, has been thrown out. _e_ represents the
healthy maxillary sinus as an empty space: _d_ is the like part, but it
is here filled by a fine cellular structure composed of bone, which has
been produced by the action of disease. The plates which form the cells
are delicately thin, and beautifully arranged: the little cavities were
once full of a thick and sanguineous matter, and the larger spaces above
them contained a very fetid but almost solid substance, which was pus,
that, by being pent up, had become of a cheesy consistency. _c_
indicates the nasal division, or cartilaginous wall, which separates the
two chambers of the nose. As will be observed, it has been forced on one
side by the enlargement of the affected parts.