Bismarck daily tribune. [volume] (Bismarck, Dakota [N.D.]) 1881-1916, 1909-03-17
The Way Nature Forms and Fixes
Them In the Gums.
THEY ARE NOT MADE OF BONE,
Teeth Are Really Skin Structures In
Respect to Their Mode Of Origin.
The Variety Of Form Which Adapts
Thorn For Varying Uses.

adequate idea regarding their true na'
: ture. If the man in the street were
asked to construct classified list OF
his bodily belongings he would almost
! certainly place teeth In the section
which included the bones, There ap.
pears reason for his choice. Teeth are
hard and bonelike In structure, and
they are fixed in tho jaws. These facts
! would seem on the face Of things to
Justify the inclusion Of the teeth In
the list of skeletal structures. This
view Of the teeth, however. is readily
proved to be incorrect. We have only
to appeal to natures way Of making
tooth-in other words, to study it's de.
velopment-to assure ourselves that
teeth are not bones ut all, but struc'
lures Of very different kind.
The first indication Of tooth forma'
ton begins in very early life with the
formation Of a groove In the gum, OF
mucous membrane lining the mouth.
This furrow is the birthplace OF the
teeth. From the groove arise as many
little projections of the gum as there
are to be teeth. Each projection we
call a papilla.
Now, this little body contains plen-
tiful supply Of blood vessels, destined
to bring to it the raw material-blood
out Of which not teeth alone, but all
other organs, tissues and secretions,
are manufactured. The papilla, be-
sides. is composed Of and particularly
invested with living cells Of special
kind. These cells are to be regarded
as the workmen which fabricate the
tooth. The material specially required
for tooth formation consists of COM
hounds of lime associated with other
| substances.
Around the papilla and upon 1t, as
on a mold, the hard material or the
tooth is deposited. 1t is elaborated
into a substance which, under the
! microscope, shows q special structure
of its own. differing widely from that
which is represented in bone. The
| great bulk Of tooth consists OF ivory
or dentine, as 1t is also called. This
Is a dense, hard substance which
shows a texture composed Of an in
finite variety Of microscopic tubules.
But at the crown Of the tooth e.
pecially we meet with q layer Of dif-
! ferent kind and Of still harder con-
sistence. This Is the enamel, which
ranks as the hardest substance in the
body. Its position on the crown OF
the tooth bears relation to the resist
ance to wear and tear the tooth is in
tended to exhibit, the softer ivory be-
ing thus protected from the obvious
results Of the process Of attrttion.
Thus on the papilla, as on living
mold, the tooth is formed, Its sub
stance coming to cover, as in an en-
velope, the little projection itself.
Long before the tooth, however, is
completed the groove in the gum has
become partitioned of into a series OF
sacs or compartments. The furrow
itself becomes converted into a tube
; by the upward growth and union OF
its edges in the middle line: Then
succeeds division into sacs, in each of
which a papilla is present and in each
of which a developing tooth is con-
tanned.
If the hard materials of the tooth be
: found around the papilla we discover
thus that the tooth is hollow and not
solid structure, for the pulp inside
every tooth, substance richly sup
; piled with nerves and blood vessels
really represents the papilla Of the
early stages. The tooths nourishment
!, is thus duly provided for, since proc
esses Of the pulp pass into the minute
tubules of the ivory and SO contribute
to the maintenance Of the vitality OF
, the organ.
When the tooth is completed within
it's sac. all that remains is for 1t to 0p
pear in the jaw, in which provision
J has been made for its fixation.
tooth ''cuts' the gum when through
: upward pressure on the sac it bursts
through It's Investment and takes the
place nature has mapped out for 1t II
:, the armamentarium Of the mouth.
:, Now, in all this history there is NJ
, hint given us of any connection be
= tween bone formation and tooth devel
opment save indeed for the connection
between the two structures in tn
- jaw. The gum is the present tissue o.
!. the teeth, and the gum Is simply thu
!, skin layer O. the body folded lnwart
at the mouth to form the lining mem
brane Of that cavity, while 1t is con
!, tinued onYard, with variations in 1T
;. organization, to form the lining of thu
digestive cubes as well. Teeth ar
therefore truly skin structures In re
! spect OF their mode Of origin, which
d after oil, is the surest and indeed thu
e only test OF the nature Of any living
+ tissue Or part.
BY all odds the very longest tooth ii
the world Is that Of the narwha]
which grows into twisted ivory poll
often exceeding six feet in length
A. Wilson in illustrated London News