Improvements in the Manufacture of Artificial Teeth.
Year: 1894

page_text: Date of Application, 12th Oct., 1894.
Complete Specification Left, 12th July, 1895-Accepted, 12th Oct... 1895
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Artificial Teeth.
ROBERT MARSTON Dental Surgeon and Dental Materials Manufacturer
2 Vectis Villas Wigston Road and JAMES PARR Cycle and Dental Materials
Manufacturer 63 Friar Lane, both of Leicester in the County of Leicester do
hereby declare the nature of this invention to be as follows:-
In order to describe the nature of our invention it may be expedient to explain
that artificial teeth are not only distinguished by the anatomical names of the various
organs which they severally represent viz. upper and lower left and right central
incisors lateral incisors cuspids bicuspids and molars but also by the names of the
several classes into which they are subdivided under the classification generally
adopted by dental manufacturers and dental surgeons. This is necessary because
the name of any particular organ would not explain whether its intended substitute
was a pin tooth, a tube tooth, or a diatoric tooth.
That surface of a front tooth which- when the tooth is in its proper position
in the month comes in contact with the lips is called the labial surface or front.
That surface which is towards the tongue is called the lingual surface or back.
That surface which rests upon the natural gum or its artificial covering is called
the "gingival surface." "the basal extremity," or the neck, whilst its other
extremity, viz. the masticator edge is commonly called the cutting edge of the tooth.
All artificial teeth are furnished with some provision for securing their
attatchment to the plate or foundation of the artificial jaw such as pin, tubes, strips,
projections, or recesses. Hence the typical names pin teeth, tube teeth, & diatoric
teeth. Now a pin tooth is a tooth furnished with one or more pins projecting
either from its lingual or else from its gingival surface. but pin teeth are very
frequently called flatbacks because of the flatness of their lingual surface.
Tube teeth are furnished with a metallic tube running in the direction of their
length from the masticatory to the gingival surface. These pins, tubes, and other
metallic contrivances are called metallic adjuncts and teeth made without mettalic
adjuncts are called diatoric teeth. All the diatoric teeth heretofore made have
been fashioned with easily mouldable cavities or projections and possibly the
difficulties of moulding have contributed to their distinct unfitness to fulfil the
requirements of partial cases and also those of entire cases, where absorbtion of
the alveolar ridge has not occured. This too may be the main reason why all
diatoric frontals have that characteristic but detrimental feature called the lingual
or occluding bevel; it is detrimental because it limits the range of the tooth's
adaptability.
The device which characterize the different makes of diatoric teeth heretofore
supplied we hereinafter enumerate for the purpose of contradistinguishing our own
nvention.
Firstly. Frontals have been made of tubular form having a vertical parallel
sided round hole running up the tooth to almost its lingual bevel and there
entering a transverse smaller but otherwise similar hole running across and right
through the tooth from side to side thus forming a T shaped throughway or
anchorage.
Secondly. Frontals have been made with a dovetail parallel sided groove running
cross and through the tooth from side to side.

page_text: Thirdly. There has also been maderfroutals having a projection on, and covering
a large proportion of the toothsilingual surface running in the direction of its
length but shaped so as to form an external marginal groove on each of its two
sides.
Our teeth differ therefrom as well as from all other diatoric teeth in being
shaped or furnished with an undercut cavity which widens as it proceeds from the
basal extremity towards, the cutting edge of the tooth whilst a transverse section
shows that the cavity in that direction widens as it proceeds from the lingual
towards the labial surface of, the tooth.
A longitudinal section shows that the floor of the cavity approximately
describes a section of a circle corresponding more or less to the outline of the
labial surface of the tooth and a perspective view of the gingival surface of the
tooth shows that the slot although open at its contracted gingival end is closed
at the masticatory end its boundary there forming, a buttment for, resisting the
forces of mastication.
Now be it known that we do not herein petition for the sole right to use any
particular formula or formulas for, the compounding of artificial, teeth.
Our object is a Patent, investing, us with the sole right to make, use, and sell
diatoric flatbacks and, to furnish them.and other, teeth with one or more undercut
cavities, whose walls, may.be either.smooth or serrated and either continuously,,open
on the lingual surface, as herein before described or perforated with suitable
.openings.
.
We apply the same auchorage to all the teeth representing the different..organs
of the mouth, to sectional gum: blocks, and to adaptable dentures. Diatoric flat-
backs, and. diatoric sectional gum blocks have never. heretofore been, supplied to
..the dental profession.
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ROBERT MARSTON.
JAMES PARR.
1
Improvements in the Manufacture of Artificial´Teeth.
ROBERT MARSTON Vectis Villas, Wigston Road Dental Surgeon,, and
Manufacturer of Mineral Teeth, and JAMES PARR Cycle Manufacturer and
*Manufacturer of Mineral Teeth 63 Friar Lane both of Leicester in the 'County
of Leicester do hereby declare the nature of this invention and in what manner
the same is to be performed; to be particularly described and ascertained in and
by the following statement:-
65
In order to. describe more distinctly the nature of our invention, it may be
expedient to explain that artificial teeth are not only distinguished by the
anatomical names of the various organs which they severally represent namely
"upper" and "lower"."left" and "right" ".central-incisors "lateral. incisors
cuspids" "bi-cuspids" and "molars" but also by the names of the several
classes into which, they, are subdivided under the classification generally adopted
by dental manufacturers and their coustomers dental surgeons; this is necessary
because the name of any particular organ would not explain whether its, intended
substitute was a "pin-tooth" a tube-tooth or a diatoric tooth.
Again, teeth are individually particularized for the purposes of describing their
external peculiarities and elucidating various instructions concerning their use
bence that surface of any front tooth which when the tooth is in its proper
position in the mouth comes in contact with the lips is called the "labial-surface
or "front" that surface which is toward the tongue is called the "lingual-
surface" or "back" that surface which rests upon the gum or its artificial

page_text: the
the
basal-surface
covering is called the "
gum surface
gingival surtace
or "neck" whilst its other extremity namely the masticatory-edge is called the
'cutting-edge" of the tooth.
"
"
The same terms are used for individually describing the "molars" and
'bi-cuspids" except that their front" which comes into contact with the wearer's
cheek is called the "buccal-surface" and their masticatory end or crown is called
the masticatory-surface.
A pin tooth is a tooth furnished with one or more pins projecting from its lingual
or else from its "gingival surface."
Pin teeth are divided into two distinct classes namely, "vulcanite pin teeth " and
"plate-teeth" the former are characterized by a projecting occlusion surface called
the "lingual-bevel."
"
"Plate-teeth are intended for metal plate work although sometimes applied to
other uses and they are sometimes called "flatbacks because of the Hatness of
their lingual surface.
Tube teeth are teeth furnished with a metallic tube running through them in the
direction of their length from the masticatory to the gingival surface. The above
mentioned pins, tubes and other metallic contrivances are called "metallic adjuncts"
and all teeth made without metallic adjuncts are called diatoric teeth. All the diatoric
teeth heretofore made have been fashioned with easily mouldable cavities or
projections and it is possible that the difficulty of moulding a suitable cavity may
have created that universal and detrimental characteristic of all diatoric front teeth
namely their protruding lingual bevel besides otherwise contributing to their
distinct unfitness to fulfil the requirements of "partial" as well as "entire cases
where absorption of the "alveolar ridge" has not occurred.
"
For the purpose of more clearly contra distinguishing our own invention we will
now proceed to enumerate the several devices adopted by makers of the diatoric
teeth heretofore supplied.
1st. Diatoric frontals have been made with a parallel sided round hole running
up the tooth almost to its lingual-bevel and there entering a transverse, smaller,
but otherwise similar hole running right through the tooth from side to side :
these had the "lingual bevel."
2nd. Diatoric frontals have been made with a straight-sided triangular groove
running across straight through the tooth from side to side: these had the
"lingual-bevel."
"
3rd. There has also been made diatoric frontals having a projection on, and
covering a large portion of the tooth's " lingual-surface and running in the
direction of its length but shaped so as to form an external marginal groove up
each side of the tooth: these teeth had the lingual-bevel.
4th. Diatoric molars and bicuspids have been made with a central parallel sided
vertical round hole running up the tooth almost to its masticatory surface and there
entering a transverse smaller hole which runs right through the tooth, from side
to side.
5th. Diatoric molars and bi-cuspids have been made with a central vertical hole
one end of which opens on the gingival surface of the tooth whilst the other end
opens on its crown or masticatory surface and there its external orifice is widened
or countersunk to prevent withdrawal.
Now be it known that our diatoric teeth differ from all others in several
important particulars. Our front teeth are fashioned with an undercut chamber
which, generally, as it proceeds up the tooth from its "gingival surface" towards
its "cutting edge" describes a section of a circle approximating the outline of the
labial surface of the tooth more or less, whilst its other end merges into or
forms a buttment for resisting masticatory force.
(Plate 1. Fig. 1, C. Fig. 2, A. Fig. 3, A.) is open
length in the form of a narrow slot (Plate 1 Fig. 1, D.
up the lingual surface of the tooth (Fig. 1, B. Fig. 2, B. Fig. 3, C.
this slot in wide teeth generally widens as it proceeds (Fig. 1) from
This undercut chamber
nearly the whole of its
Fig. 2, A. Fig. 3, D.)
Fig. 3, G.)
the gingival

page_text: surface (Fig. 1, A. Fig. 3, E.) towards its cutting edge (Fig. 1, E. Fig. 2, D.
Fig. 3, F.) but in very narrow teeth we sometimes either run the slot (Fig. 1, D.
Fig. 2, A. Fig. 3, D.) straight or give it a slight lateral curvature or else a
zigzag, serrated, or serpentine form. Our anchorage being admirably applicable
to flatbacks we preferably make "diatoric flatbacks for the front of the month.
We do not however restrict ourselves to this use of our anchorage for we embody
it in teeth of every other pattern whenever special requirements indicate the
advisability or necessity of doing so.
"
It now appears from what has been said that a perspective view of the gingival
(Fig. 1, A. Fig. 2, E. Fig. 3, E.) and lingual (Fig. 1, B. Fig. 2, B. Fig. 3, G.)
surfaces of a front tooth shews that in wide teeth the under cut chamber (Fig. 1, C.
Fig. 2, A. Fig. 3, A.) and its contracted slot (Fig. 1, D. Fig. 2, A. Fig. 3, C.)
widen as it proceeds up the tooth from its gingival surface (Fig. 1, A. Fig. 3, E.)
towards its cutting-edge (Fig. 1, E.) and that although the slot. (Fig. 1, D.
Fig. 2, A. Fig. 3, C., is open at its gingival end it is closed at the masticatory
end there forming the buttment (Fig. 1, F. Fig. 3, H.). A transverse section
(Fig. 2) shews that the cavity widens as it proceeds from the lingual (Fig. 2, 'B.)
surface towards the labial surface (Fig. 2, C.) and a longitudinal section (Fig. 3)
shews that the chamber (Fig. 3, A.) approximately describes the outline of the
labial surface (Fig. 3, B.) of the tooth. It will also appear on referring to
(Plate 1. Fig. 3.) that the labial surface of a very short front tooth is practically
straight and their are many types of long teeth that are perfectly straight too.
Therefore in describing the labial outline of such teeth it follows that the chamber
must also be straight and the anchorage becomes thereby diminished so far as it
relates to withdrawal of the tooth from any dental appliance. In such cases the
utility of the shaped, the 'T shaped, the lateral-curviform-shaped, the zig zag
shaped, and the serpentine form of the lingual slot (Fig. 1, D. Fig. 1, F.
Fig. 2. A. Fig. 3, C. Fig. 3, D.) becomes self evident. Either of these
marginal lateral distortions of the chamber (Fig. 1, C.
Fig. 3, A.)
and its lingual contracted inlet; the slot: (Fig. 1, D.
Fig. 3, C.)
effectually prevents withdrawal of the tooth.
a
Fig. 2, A.
Fig. 2, A.
Instead however of resorting to these forms of obstruction to withdrawal we
sometimes mould the teeth of such a shape that their gradually diverging labial
and lingual surfaces in a longitudinal section look something like the two sides of
long narrow cone whose base is the gingival surface; and its apex is the cutting
edge. All front teeth are more or less of this shape but for the purpose of
increasing the anchorage of teeth of this class we sometimes thus exaggerate the
natural deflection of the labial and lingual surfaces and thereby cause the pro-
portionately thickened walls of the slot (Fig. 3, D. Fig. 3, C.) to become
narrower as they proceed up the tooth. From the gingival surface (Fig. 3, E.)
towards its cutting-edge (Fig. 3. F.) this affords a grip which effectually prevents
withdrawal, but whenever teeth having a straight labial surface can be made thick
enough to allow it we prefer to make the chamber describe the section of a circle
although by doing so it does not approximately describe the outline of the labial
surface of the tooth.
In very thin front teeth having straight labial surfaces, withdrawal is sometimes
prevented by forming prominences or depression on the 'lingual surface.
Prominences on the tooth produce corresponding depressions in the surrounding
coaptated vulcanite or other basal substance; whilst depressions in the tooths'
lingual-surface produce corresponding prominences in the surrounding mouldable
vulcanite or other material composing the plate" and thus this interlocking of the
contact surfaces of the tooth and base effectually prevents intentional, or accidental,
separation by withdrawal.
We apply the same anchorage to all teeth representing the different organs of
the mouth, also to "sectional-gum-blocks " and to adaptable porcelain entire
dentures."
Whatever class of tooth we apply our anchorage to, whenever it is possible, we

page_text: prefer to make it approximately describe the shape of the tooth's labial. surface
(Fig. 3, A. Fig. 3, B. Fig. 4, 2. Fig. 7, 2.) and have it open on both the
lingual (Fig. 1. B. Fig. 2, B. Fig. 3, C. Fig. 3, H. Fig. 4, 1. Fig. 5, 1.
Fig. 8, 1.) and gingival (Fig. 1, C. Fig. 3, E.
Fig. 7, 2. Fig. 8, 2.) surfaces.
Fig. 6, 1. Fig. 7, 1.
Fig. 5, 2. Fig. 6, 2.
I
'
"
Fig. 4; 2.
The sectional drawing (Fig. 4) shews that half of an inverted molar which is
.circumscribed by the lingual (1), gingival (2), buccal (3), and the masticatory (4)
surfaces and describes its anchorage.
Fig. 5 shews a perspective view of the gingival surface of a molar and its
contracted slot of the anchorage chamber (Fig. 5, 2. Fig. 5, 3.).
Fig. 6. shews both the lingual (1) and gingival (2) surfaces of an inverted.
molar.
Fig. 7 shews how the anchorage chamber approximately describes the shape of a
large molar.
Fig. 8 shews the approximal surface (5)-namely the side-of an inverted
molar, circumscribed by the lingual (1), gingival (2), buccal (3), and masti-
catory (4) boundaries.
Although the anchorage chambers (Fig. 1, C. Fig. 4, 1. Fig. 4, 2. Fig. 6, 1.
Fig. 6, 2.) are mostly oblong or conical we do not restrict ourselves to these
shapes, we sometimes use square, oval, round, half-round, and other shapes, but
whatever shape we use our principle of anchorage always remains the same
namely An undercut cavity which as much as is practicable approximately
describes the shape of the tooth and opens on both its lingual and gingival
surfaces.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is.
1st. The sole right to make use and sell "diatorie-flatback" front teeth.
2nd. The sole right to make use and sell diatoric frontals (front teeth) of every
shape, fashioned with a cavity having a contracted opening or slot on the lingual
surface and running up in the direction of the length of the tooth from its gingival
surface towards its cutting-edge the cavity being open on both the gingival and
lingual surfaces.
3rd. The sole right to make use and sell diatoric front teeth having a straight, a
V shaped, a T shaped, a lateral-curviform shaped, a zigzag shaped, a serpentine
shaped, or other shaped, undercut slot, running up the tooth, in the direction of its
length namely from its gingival surface towards its cutting-edge and open on both
its gingival and lingual surfaces.
4th. The sole right to make use and sell diatoric frontals having an anchorage-
chamber which as it proceeds up the tooth from its gingival surface towards its
cutting edge describes an undercut section of a circle.
5th. The sole right to make use and sell diatoric frontals having an undercut
cavity which as it proceeds up the tooth from its gingival surface towards its
cutting-edge approximately describes the outline of the labial surface of the
tooth.
6th. The sole right to make use and sell diatoric molars and bi-cuspids having
an undercut cavity whien in longitudinal section approximately describes the
outline of the masticatory and buccal surfaces and is open on both the gingival
and lingual surfaces of the tooth.
7th. The sole right to make use and sell diatoric molars and bicuspids having au
undercut cavity which widens as it proceeds from the lingual, towards the buccal
surface of the tooth, being open on both the lingual and gingival surfaces.
8th. The sole right to make use and sell diatoric front and back teeth having two
cavities shaped as herein before described.
9th. The sole right to apply our invention to every lawful use and exercise
namely the construction of artificial dentures and other dental appliances and if we

page_text: think fit-also to furnish the aforesaid diatoric teeth with pins, strips, and loops,
by surrounding such metallic contrivances placed endwise in the anchorage cavity
with cement, metal or any other suitable element or compound capable of securely
affixing the same.
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1002
ROBERT MARSTON.
JAMES PARR.