The Teeth The Ivory Keepers Of The Gate
Categories:
INFECTIONS, AND HOW TO AVOID THEM
Sources:
A Handbook Of Health
Why the Teeth are Important. The teeth are a very important part of
our body and deserve far more attention and better care than they
usually get. They are the first and most active part of our digestive
system, cutting up and grinding foods that the stomach would be unable
to melt without their help. In all animals except those that have horns
or fists, the teeth are their most important weapons of attack and
defense.
So important are they in all animals, including ourselves, and
so closely do they fit their different methods of food-getting and of
attack and defense, that when scientists wish to decide what class, or
group, a particular animal belongs to, they look first and longest at
its teeth.
The shape and position of the teeth literally make the lower half of the
face and give it half its expression. A properly grown and developed set
of teeth not only is necessary to health and comfort, but helps greatly
to make the face and expression attractive or unattractive. Few faces
with bright eyes, clear skin, and white, regular, well-kept teeth are
unpleasing to look at. Beauty and health are closely related, and we
ought to try to have both. In fact, nine times out of ten, what we call
beauty is the outward and visible sign of inward health. The healthier
you are, the handsomer you'll be.
It is particularly important to understand the natural growth and proper
care of the teeth because there are few organs in the body for which we
are able to do so much by direct personal attention. Our stomachs, our
livers, and our kidneys, for instance, are entirely out of sight, and
more or less out of reach; but our teeth are both easily got at and in
full view; and, to a large degree, upon the care that we give them while
they are young, will depend not only their regularity and whiteness, but
also the length of their life and the vigor and comfort of our digestion
all our lives.
The first thing to be remembered about the teeth is that, hard and shiny
and different from almost everything else in the body as they look, they
are simply a part of the skin lining the mouth, hardened and shaped for
their special work of biting and chewing. Much of the care needed to
prevent decay should be given, not to the teeth themselves directly, but
to the gums and the mucous membrane of the whole mouth. The gums and the
mouth literally grew the teeth in the first place; and when they
become diseased, they secrete acids which slowly eat away the crowns and
roots of the teeth. Their diseases come chiefly from irritation by
decaying scraps of food, or from the blocking of the nose so that air is
breathed in through the mouth, drying and cracking the soft mucous
membrane. After the acids from the diseased gums have attacked the
teeth, the poisons of the germs that breed in the warmth and moisture of
the mouth cause the teeth to decay. Eight times out of ten, if you take
care of the gums the teeth will take care of themselves.
Structure of the Teeth. The upper half of the tooth, which pushes
through and stands up above the jaw and the gum, we call the crown;
and this is the portion that is covered with enamel, or living
glass. The body of the tooth under the enamel is formed of a hard kind
of bone called dentine. The lower half of the tooth, which still is
buried in the jaw, we call the root. Wrenching the lower or root part
of the tooth loose from its socket in the jaw is what hurts so when a
tooth is pulled. The crown of the tooth is hollow, and this hollow is
filled with a soft, sensitive pulp, in which we feel toothache. Tiny
blood vessels and nerve-twigs run up from the jaw to supply this pulp
through canals in the roots of the tooth.
Kinds of Teeth. If you look at your own teeth in a mirror, the first
thing that strikes you is your broad, white, shiny front teeth, four
above and four below, shaped like the blade of a rather blunt chisel.
Their shape tells what they are used for. Like chisels, they cut, or
bite, the food into appropriate sizes and lengths for chewing between
the back teeth; and from this use they are called the incisors, or
cutters. From having been used for so many generations upon the kind
of food we live on, they have grown broader than the canines, the
teeth next to them, and almost as long.
The canines are of a cone-like shape, although it is a pretty blunt
cone, or peg. Those in the upper jaw lie almost directly under the
centre of each eye, and are called the eye-teeth; though their proper
name, from the fact that they are the most prominent teeth in the dog,
is the canine teeth. These are our oldest and least changed teeth; and
as you might guess from their shape, like a heavy, blunt spear-head,
were originally the fighting and tearing teeth, and still have the
longest and heaviest roots of any teeth in our jaws. If you slip your
finger up under your upper lip, you can feel the great ridge of this
root, standing out from the surface of the gum.
Lastly, looking farther back into our mouths, we see behind our canines
a long row of broad, flat-topped, square-looking teeth, which fill up
the largest part of our jaws. Again their shape tells what they are used
for. They are not sharp enough to cut with, or pointed enough to tear
with, but are just suited for crushing and grinding into a pulp, between
their broad, flat tops, any food that may be placed between them; and
from this grinding they are called the molars, or mill teeth. If you
will look closely at the back ones, you will see that each of them has
four corners, or cusps, with a cross-shaped, sunken furrow in the
centre, where they come together. After they have been used in grinding
food for some years and rubbing against each other, these little corner
projections become worn away, and their tops become almost flat. Those
in the upper jaw have three roots, and those in the lower jaw have two,
so that they are solidly anchored for their heavy, grinding work. The
first two molars in each jaw, behind the canines, are smaller than the
others and made up of only two pieces instead of four, and hence are
called the bicuspids, or two-cusped teeth.
As we are what the scientists call an omnivorous, or all-devouring,
animal, able to eat and live upon practically every kind of food that
any animal on earth can deal with,--animal and vegetable, soft and hard,
wet and dry; fruits, nuts, crabs, roots, seaweeds, insects, anything
that we can get our teeth into,--we have kept in working condition some
of every kind of teeth possessed by any living animal; and the most
important rule for keeping our teeth in health is to give all these
kinds something to do.
Just as in other animals the teeth appear when needed, and grow into the
shape required, so they grow in our own mouths when they are wanted, and
of the size and shape required at the time. We are born without any
teeth at all; and it is only when we begin to need a little solid food
added to our milk diet,--when we are about seven months old,--that our
first teeth appear; and these are incisors, first of all in the lower
jaw. Then, at average intervals of about three months, the other
incisors and the canines appear and, last of all, the molars, so that at
about two years of age we have a complete set of twenty teeth. These are
called the milk teeth.
Most animals (mammals) have formed the habit of growing two sets of
teeth--a smaller, slighter set for use during the first few months or
years of life, and a larger, heavier set to come in and take their place
after the jaws have grown to somewhat more nearly their permanent size.
In our mouths, at about seven years of age, a larger, heavier tooth
pushes up behind the last milk tooth,--called the seventh year
molar,--the milk teeth begin to loosen and fall out, and their places
are taken by other new teeth budding up out of the jaw just as the first
set did. These take a still longer time to grow, so that the last four
of the full set of thirty-two do not come through the gums until
somewhere between our eighteenth and twentieth years. These last four
teeth, for the rather absurd reason that they do not appear until we are
old enough to be wise, are known as the wisdom teeth. Instead of
being, as one might expect, the hardest and longest-lived of all our
teeth, they are the smallest and worst built of our molars and among the
first of our permanent teeth to break down and disappear. Not only so,
but our jaws are so much shorter than they were in the days when man
fought with his teeth and knew nothing about cooking and had no tools or
utensils with which to grind and prepare his food, that there is
scarcely room in them for these last teeth to come through. They often
cause a great deal of pain in the process, and may even break through at
the side of the jaw and cause abscesses and other troubles.
Care of the Teeth. The most important thing for the health of any
organ in the body is to give it plenty of exercise, and this is
especially true of our teeth. This exercise can be secured by thoroughly
chewing, or masticating, all our food, of whatever sort, especially
breads, biscuits, and cereals. Thorough chewing not only gives valuable
exercise to the teeth, but, by grinding up these foods thoroughly, makes
them easier for the stomach to digest; and, by mixing them well with the
saliva, enables it to change the starch into sugar. Meats, fish, eggs,
cheese, etc., do not need to be mixed with the saliva, nor to be ground
so fine for easy digestion in the stomach, and hence do not require such
thorough chewing, though it is better to make a rule of chewing all
food well. We can exercise our teeth also by eating plenty of foods that
require a good deal of chewing, especially the crusts of bread, and
vegetables such as corn, celery, lettuce, nuts, parched grains, and
popcorn.
It is most important to keep the nasal passages clear and free, and the
teeth sound and regular by proper dental attention, so that the jaws
will grow properly, and each tooth will strike squarely against its
fellow in the opposite jaw, and both jaws fit snugly and closely to each
other, making the bite firm and clean, and the grinding close and
vigorous. If we are mouth-breathers, our jaws will grow out of shape, so
that our teeth are crowded and irregular and do not meet each other
properly in chewing. Pressure upon the roots of the teeth, from meeting
their fellows of the opposite jaw in firm, vigorous mastication, is one
of the most important means of keeping them sound and healthy. Whenever
a tooth becomes idle and useless, from failing to meet its fellow tooth
in the jaw above or below properly, or from having no fellow tooth to
meet, it is very likely to begin to decay.
The next important thing in keeping the teeth healthy is to keep them
thoroughly clean. The greatest enemies of our teeth are the acids that
form in the scraps of food that are left between them after eating.
Meats are not so dangerous in this regard as starches and sugars,
because the fluids resulting from their decay are alkaline instead of
acid; but it is best to keep the teeth clear of scraps of all kinds.
This can best be done by the moderate and gentle use of a quill, or
rolled wooden tooth-pick, followed by a thorough brushing after each
meal with a rather stiff, firm brush. Then use floss-silk, or linen or
rubber threads to saw out such pieces as have lodged between the
teeth.
This brushing should be given, not merely to the teeth, but to the
entire surface of the gums as well; for, as we have seen, it is the gums
that make or spoil the health of the teeth, and they, like all other
parts of the body, require plenty of exercise and pressure in order to
keep them healthy. In the early days of man, when he had no knives and
gnawed his meat directly off the bones, and when he cracked nuts and
ground all his grain with his teeth, the gums got an abundance of
pressure and friction and were kept firm and healthy and red; but now
that we take out the bones of the meat and stew or hash it, have all our
grain ground, and strip off all the husks of our vegetables and skins of
our fruits, though we have made our food much more digestible, we have
robbed our gums of a great deal of valuable friction and exercise. The
most practical way to make up for this is by vigorous massage and
scrubbing with a tooth-brush for five minutes at least three times a
day. It will hurt and even make the gums bleed at first; but you will
be surprised how quickly they will get used to it, so that it will
become positively enjoyable.
It is good to use some cleansing alkaline powder upon the brush. The
old-fashioned precipitated chalk, which makes the bulk of most tooth
powders, is very good; but an equally good and much cheaper and simpler
one is ordinary baking soda, or saleratus, though this will make the
gums smart a little at first. Any powder that contains pumice-stone,
cuttle-fish bone, charcoal, or gritty substances of any sort, as many
unfortunately do, is injurious, because these scratch the enamel of the
teeth and give the acids in the mouth a chink through which they may
begin to attack the softer dentine underneath the glaze of enamel.
Antiseptic powders and washes, while widely advertised, are not of much
practical value, except for temporary use when you have an abscess in
your gums, or your teeth are in very bad condition. It is almost
impossible to get them strong enough to have any real effect in checking
putrefaction of the food or diseases of the gums, without making them
too irritating or poisonous. If you keep the gums and teeth well brushed
and healthy, you will need no antiseptics.
Not only should the teeth be kept thoroughly clean and sweet for their
own sake, but also for the sake of the stomach and the health of the
blood and the whole body. The mouth, being continually moist and warm
and full of chinks and pockets, furnishes an ideal breeding ground for
all kinds of germs; and the average, uncleansed human mouth will be
found to contain regularly more than thirty different species of germs,
each numbering its millions! Among them may sometimes be found the germs
of serious diseases such as pneumonia, diphtheria, and blood-poisoning,
just waiting, as it were, their opportunity to attack the body. In fact,
a dirty, neglected mouth is one of the commonest causes of disease.