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The Teeth The Ivory Keepers Of The Gate

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

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


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


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.