Note: Descriptions are shown in the official language in which they were submitted.
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APPLICATOR AND METHOD OF APPLYING
Background of the Invention
The present invention relates to an applicator, as well as a
method of applying, especially for dental purposes. The applicator
includes an application element having a grip area and a working
end. An application member is disposed at the working end and is
provided with at least one reaction substance, especially with at
least one catalyst.
An applicator of this type is known from D.E.-U1-92 18 949.
With this applicator, an application member is accommodated in a
case having holes on the side via which a fluid can enter that
serves for wetting the application member.
This approach is intended to prevent the fluid from escaping
if the applicator is, for example, tipped over. For this purpose,
sealing surfaces are provided between the case and the
application element.
Such an approach may work with cosmetic products.
However, in the dental area a precise introduction of an application
element is critical. Even if with D.E.-U1-92 18 949 relatively small
holes are provided in the case, with which a certain amount of
protection is intended, this cannot preclude the fluid from
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accidentally penetrating and hence wetting the application element
already prior to the actual process of using the same.
Numerous other applicators are also know. For example, it
has been proposed to maintain an application element immersed
in a liquid, and by pressing down the container for this liquid to
allow a further liquid to flow in the manner of an overflow in order to
prepare the mixture that is to be applied. Since this approach
requires two separate sealing systems, a not inconsiderable
expense is required. In addition a number of sealing bands or the
like means a correspondingly great susceptibility and storage
instability.
In this connection, is as furthermore known to accommodate
the liquids in two chambers that are separated by a membrane that
is precisely destroyed by a spike that can be activated by pressing
an inner housing in. This approach, however, requires a special
configuration of the spike to reliably prevent the spike from colliding
with the application element.
It is furthermore known to mix reactive substances, such as
a composite for tooth fillings, on a base that is coated with a
peroxide, or to mix the composite with a peroxide-coated spatula.
This mixing has the drawback that a homogeneous mixing is not
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- possible since it cannot be recognized when the peroxide has been
completely consumed by the relatively viscous material.
It is therefore an object of the present invention to provide
an applicator of the aforementioned general type that is
economical to produce and that enables an improved handling
relative to the state of the art yet provides a good storage stability,
whereby in particular a homogeneous mixing of a fluid should be
possible and an ease of operation together with a saving in time
should be achieved.
Brief Description of the Drawings
This object, and other objects and advantages of the
present invention, will appear more clearly from the following
specification in conjunction with the accompanying schematic
drawings, in which:
Fig. 1 is a cross-sectional view through one
exemplary embodiment of an inventive
applicator; and
Fig. 2 is a cross-sectional view through a further
exemplary embodiment of an inventive
applicator.
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- Summary of the Invention
The applicator of the present invention is characterized
primarily in that the application member is comprised of a
deformable material, especially a~n elastically deformable material,
wherein the application member serves for receiving the reaction
substance in solid, liquid or semisolid form, with which a low
viscosity fluid can be activated.
Pursuant to the present invention, the application member,
in other words, for example, one and of the application element, is
first provided with one or more reaction substances. For example,
a double catalyst system as a salt can be applied. The inventive
application element is then immersed in a special liquid, which
accompanied by formation of a drop surrounds the application
member.
The inventive application element is then immersed in a
liquid, for example a dental adhesive, that accompanied by the
formation of a drop surrounds the application member. The
application element is then introduced into the mouth of the
patient, and during the actual application process the adhesive is
mixed into a cavity or upon a dentine or enamel surface with the
catalyst. The catalysts that might be present in the adhesive react
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- with the catalysts of the application member, and the entire mass
hardens or sets. It is also conceivable to place only a single
catalyst on the application member that, for example, increases or
reduces the viscosity of the adhesive.
It is particularly expedient pursuant to the present invention
that the application of the adhesive to the application surface
particularly promotes even obviously chemical reactions. Due to
the distribution of the adhesive, even the salt present on the
application member as reaction substance is well released, so that
the self hardening process is enhanced. In this connection,
pursuant to the present invention it is particularly expedient that the
applicator eliminates the necessity for light hardening of the
applied adhesive. Thus an entire process step, for example during
introduction of an inlay or during fastening of a crown, is
eliminated.
Pursuant to the present invention, the application member
comprises a deformable material. In this context, "deformable"
means a material hardness that is suitable for the application.
Thus, for example, the applicator can comprise a polymeric
material, with the application member extending essentially in the
form of a small rod to a working end. At this end, the inventive
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- application member is provided, which is either monolithic, in other
words comprises the same material as the rest of the application
element, or is comprised of some other material. For example, the
material for the application member can be a textile, brush hairs, a
sponge, fibers, polymeric material, hard or laminated paper, or
wood, with the configuration of a micro-brush being preferred. in
addition, it is preferable that the material of the application member
be significantly softer than dentine and tooth enamel in order
during application not to have to worry about any damage to the
tooth.
Pursuant to the present invention it is particularly important
to have the viscosity of the liquid or fluid in the range of 10 to
500,000 mPa, especially 1,000 to 100,000 mPa, and preferably
10,000 to 50,000 mPa. The low viscosity ensures that the reaction
substance will be released entirely to the application member, as
has shown to be the case in tests conducted with an inventive
applicator. The small brush hairs of a micro-brush used pursuant to
one advantageous specific embodiment of the present invention
evidently produce capillary effects so that with an appropriate
viscosity the liquid creeps along the hairs and can directly release
the reaction substance. In addition, as a liquid adhesive it enables
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- a laminar spreading on the application surface, to which
_ contributes the very low surface tension of the liquid.
Pursuant to the present invention, it is particularly expedient
that the application member itself be provided with the reaction
substance that can be activated by the liquid. The reaction can be
activated by pushing in a housing that contains the fluid, or by
immersion into an otherwise suitable container.
If a housing is used, it is merely necessary to provide a
circumferential sealing of the sealing mechanism in order to
maintain storage stability. The inventive application member is
preferably provided with one or more catalyst. For this purpose, it
is immersed into a benzene sulfinic acid solution and/or into an
amine solution, for example diethanol-p-toluidine, and allowed to
dry. The reaction substance is stored as a dry substance and is
hence particularly stable. Therefore, as a reaction substance a
double coating by two catalysts can also be applied, so that with
the activation upon introduction of the sealing mechanism and
overcoming of the sealing function by the fluid, in practice three
components are brought together and react appropriately, whereby
the fluid is used as adhesive for the adhesion of composite
materials upon tooth enamel or dentine.
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In this embodiment, the inventive applicator can be made
available as a single-dose unit. However, in other embodiments it
is also possible to separately prefabricate and package the
application member, for example as an individual brush or brush
comb, and to immerse it into the fluid for use. The single-dose unit
or the individual or multiple brush (brush comb) can preferably be
sealed in foil, for example of aluminum, or coated plastic, in order
to improve the storage stability. If, for example, larger cracks are to
be sealed or tooth enamel is to be applied, an adequate quantity of
material can be made available in this manner.
It is particularly expedient pursuant to the present invention
if the reaction substance is present in solid form. However, this is
by no means absolutely necessary, since it is also possible to
provide the material in semisolid or even liquid form as drops.
Depending upon the type of fluid, not only a light hardening but
also a self hardening adhesive can be made available.
It is particularly advantageous pursuant to the present
invention to provide quite wide slots for the supply of the fluid to the
application member. When the application element, in other words
the seal, is strongly pushed into the housing, the fluid is pressed
upwardly, accompanied by pronounced swirling, through the gap
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between the base of the sealing mechanism and the inner side of
the housing, and flows at a quite high flow velocity into the region
provided with micro hairs. As a consequence, an intensive mixing
results, so that the chemical reaction is very rapidly initiated by the
catalysts, and the finished adhesive is immediately ready for use.
The required reaction time can, for example, be one second; the
time does not generally fall below such a short time span.
To this extent, with surprisingly simple measures an
applicator is made available that on the one hand is stable for a
long time and on the other hand is rapidly usable.
Pursuant to one particularly advantageous specific
embodiment to the present invention, even the sealing mechanism
can be pressed down with the application element. This can be
realized either with the blunt tip of the application member, or with
an appropriate projection of the shaft of the application element.
It is furthermore particularly advantageous pursuant to the
present invention if the application member is embodied as a
micro-brush. Such a micro-brush can be produced by flocking the
tip of the shaft of the application element. Within the context of the
present invention, the application member means any type of
application mechanism produced by applying an absorptive
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- substance onto the shaft tip, so that even a foam type of structure
_ could be provided.
The absorptive capacity of the micro-brush for the fluid can
be adapted to the desired application volume in conformity with the
hair length, in other words the type of flocking, or by other suitable
measures, For example, to wet larger tooth surfaces, which
correspondingly require more adhesive agent, it can be expedient
to provide a micro-brush having a greater drop receiving capacity
for the fluid, with the brush hairs extending to the side supports of
the sealing mechanism.
Pursuant to another particularly expedient embodiment of
the present invention, such an applicator can be bendable in a
particularly advantageous manner. For this purpose, a constriction
or narrowed portion can be provided about the shaft of the
application element to permit a plastic deformation of the
application element such that it can be bent after removal from the
housing.
This bending can, in a particularly expedient manner, be
effected in such a way that the application element is first
withdrawn by a few millimeters from the housing and is then bent.
In this state, the micro-brush is still protected by the housing so
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- that no separate additional bending tool is needed.
_ Pursuant to another particularly advantageous specific
embodiment of the present invention, the constriction can be
disposed just below a widened or thickened portion, the front
abutment shoulder of which at the same time serves for
introduction of the sealing mechanism. The widened portion then
at the same time forms the transition between the grip and the
shaft, and offers to the dentist an ergonomically favorable handling
reliability that prevents him from inadvertently contacting the tip
region of the application element that carries the reaction
substance while he guides the application element.
Pursuant to a further advantageous specific embodiment,
the grip, which is adjacent to the widened portion, can be provided
with grooves or other suitable surface configurations that provide a
favorable grip.
The inventive applicator can be produced decidedly
economically as a single-dose unit, with the micro-brush preferably
being made of polypropylene.
The inventive sealing mechanism fulfills a number of
functions in a particularly expedient manner. On one hand, the
base of the sealing mechanism, prior to use of the applicator,
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- reliably seals against an inner annular bead of a housing. It is
preferably made of a polymeric material that is somewhat softer
than the material of the housing. At the same time, it serves for
guiding the shaft of the application element, in which connection it
is preferred that the friction between the shaft and the sealing
mechanism on the one hand, and between the sealing mechanism
and the housing on the other hand, also be great enough in the
region of the upper overflow ring that the components of the
invehtive applicator do not inadvertently fall apart.
It is to be understood that prior to use the inventive
applicator is accommodated in a suitable, preferably air tight,
package so that also the reaction substance is not subjected to
any environmental influences through the narrow gap, the ring of
the sealing mechanism, and the shaft.
Further specific features of the present invention will be
described in detail subsequently.
Description, of Preferred Ernb4diments
Referring now to the drawings in detail, the applicator 10
illustrated in Fig.1 is provided with a housing 12 in which is guided
an essentially cup-shaped sealing mechanism 12, which in turn
accommodates an application element 16.
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The lower region of the housing 12 is provided with a
_ receiving portion 18 for a fluid or liquid 20. The housing 12 is also
essentially cup-shaped and is provided at its upper end with a
reinforcing rim 22 that is embodied as an outwardly directed collar.
Somewhat less than half way along the housing 12 the latter
is provided with an inwardly directed bead 24 that has an
essentially convex configuration and serves for providing a sealing
against a base 26 of the sealing mechanism 14.
For this purpose the base 26 of the sealing mechanism 14
is slightly oversized relative to the inner diameter of the bead 24.
Pursuant to one particularly advantageous embodiment, the outer
periphery of the base 26 is slightly concave so that a certain
arresting function results for fixing the sealing mechanism 14 in a
direction toward the top and the bottom.
The sealing mechanism 14 is provided above the base 26
and to the side with two rather large recessed areas 28 and 30 that
extend over nearly the entire height of the sealing mechanism 14.
When the sealing mechanism 14 is pushed in, the fluid 20 can
easily and rapidly flow through the recessed areas 28 and 30.
To delimit the recessed areas 28 and 30, the sealing
mechanism 14 is furthermore provided with two rods or supports
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- 32 and 34 that connect the disc or plate-shaped 26 of the sealing
mechanism with a ring 38 that in the shape of a circular ring
extends between the annular gap that exists between the
application element 16 and the upper end of the housing 12.
The connection or termination ring 38 is provided with an
outwardly directed shoulder 40, the amount of projection of which
is somewhat less than the projection of the bead 24 of the housing
12. As a consequence of this construction, the sealing mechanism
14 is axially movably guided in the housing, wherein in order to
overcome the sealing function of the sealing mechanism at the
base 26, a certain amount of force must be applied.
This force can inventively be applied via the application
element 16. The application element has a grip area 42 which in
this embodiment is not illustrated (but see Fig.2). Via a tapered
area, the grip 42 merges with a shaft 44 that ends in a region 46
that is provided with micro hairs. This region forms an inventive
application member 50, which in this embodiment is illustrated in
the form of a micro-brush. In the illustrated embodiment, the micro-
brush 50 is formed by a flocking, so that numerous, irregularly
disposed brush hairs 52 extend outwardly.
The micro-haired region 46 ends in a rather blunt tip 54.
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This enables the transmission of force to the base 26 of the sealing
mechanism 14, and hence the introduction of the sealing
mechanism to activate the applicator 10.
In the embodiment illustrated in Fig.1, the brush hairs 52 are
rather short. The length of the hairs affects the absorption or
receiving capacity not only for the reaction substance, which is
applied there as a deposited salt, but also for the fluid 20. This
embodiment is suitable for applying particularly small quantities of
adhesive.
Fig.2 shows a modified embodiment of the inventive
applicator. Where applicable, the same reference numerals have
been used for the same components and require no further
explanation. In contrast to the embodiment of Fig.1, the shaft 44
of the application element 16 in this embodiment has a conical
shape. In addition, the brush hairs 52 are longer and extend to the
supports 32, 34. Furthermore, in this embodiment the introduction
of the sealing mechanism.14 is effected not via the tip 54 of the
application element 16, but rather via an abutment shoulder 56 that
is formed on a widened portion 58 that in this embodiment
separates the grip 42 from the shaft 44 and is intended for
abutment of the top against the ring 38.
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Somewhat below the abutment shoulder 56 there is
provided in this embodiment a constriction or groove 60 that offers
the possibility of bending the shaft 44 relative to the grip 42. Due to
the configuration of the application element 16, a plastic
deformation is possible, whereby tests have shown that the shaft
44 springs back only somewhat relative to the grip 42 from the bent
position.
The distance between the upper side of the base 26 and the
upper side of the ring 38 is somewhat greater than the distance
between the tip 54 and the abutment shoulder 56. This ensures
that the micro-brush 50 can be entirely accommodated in the
essentially cup-shaped sealing mechanism 14 without the brush
hairs 52 getting bent at the base 26.
In this embodiment, the housing 12 is relatively stable, so
that it can also endure rather rough handling. On the other hand,
the plastic or polymeric material of the sealing mechanism 14 is
much softer, so that the sealing function is ensured. Also with this
embodiment the shoulder 40 is somewhat conical, so that there
results a certain sealing function relative to the housing 12 and
also the reaction substance on the micro-brush 50 is
accommodated in a sealed manner.
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Pursuant to a further modified embodiment, it is provided
that the ring 38 has an inwardly directed bead that somewhat
engages the constriction 60. As a consequence of this
configuration, the application element 16 can be reliably supported
in the sealing mechanism 14.
The following is a list of the process steps that are
necessary for the conventional adhesive restorative dentistry. For
the direct restoration with a composite filler, the following steps are
required;
1. Remove decay.
2. _ Clean, dry and if necessary place an under-filling.
3. Etch dentine and enamel.
4. Apply Syntax-component with a brush.
5. Wait 20 seconds.
6. Blast with air.
7. Twenty second light polymerization.
8. Apply second layer as above.
9. Application of the composite and fight hardening.
With the inventive applicator and the inventive
method, it is possible to eliminate steps 5 to 7, and depending
upon the application also step 8, so that the application process is
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accelerated and simplified, which is also an advantage with regard
_ to failure reliability since each separate process step must be
carried out with great care for a good restoration result.
The specification incorporates by reference the disclosure of
German priority document 199 56 705Ø
The present invention is, of course, in no way restricted to
the specific disclosure of the specification and drawings, but also
encompasses any modifications within the scope of the appended
claims.
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