Note: Descriptions are shown in the official language in which they were submitted.
TITLE: PROTECTIVE SHIELD FOR DENTAL IMPLANT
FIELD OF THE INVENTION
[1] The present invention relates in general to the dentistry industry and
in specific to
a protective shield for preventing pen-implant diseases in implant patients.
BACKGROUND OF THE INVENTION
[2] Cement-retained dental implant treatment has been successful and
favourable
over screw-retained treatment to restore lost teeth due to an associated
number
of advantages. These include easier control of occlusion, higher esthetic
results,
good passive fitness, fewer complex manufacturing procedures, lower costs, and
similarity to conventional methods of restoration in natural teeth.
Nonetheless,
cement-retained implants carry a problem of leaving excess cement on the
implant or in the surrounding soft tissues, which has been associated with pen-
implant disease and consequent implant failures. "Pen-implant disease" is
"disease that affects the tissues associated with an oral implant and/or
abutment.
Bacteria grow in the soft tissue (mucositis) or progress to the supporting
bone and
induce its destruction (peri-implantitis).
[3] This problem has caused clinicians to choose screw-retained
restorations, despite
their deficiencies, such as lower esthetic results and reduced effective
occlusal
surface. The problem has been proven in several studies. A study involved 20
females and 19 males, ranging in age from 41 to 78 years, who used 34 of 42
test
implants (80.95%) and no control implants (0%). Of the 33 test implants
available
for evaluation at the 1-month interval, the clinical and endoscopic signs of
peri-
implant disease had resolved in 25 implants. The study concluded that excess
dental cement was associated with signs of pen-implant disease in the majority
(81%) of the cases. Clinical and endoscopic signs of pen-implant disease were
absent in 74% of the test implants after the removal of excess cement. All
types
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of excess cement observed were associated with pen-implant disease. The pen-
implant disease was not cement-specific ¨ all types of cement can cause the
disease.
[4] There are some unspecific methods trying to avoid excess cement
during implant
prosthesis cementation such as using a rubber dam or replica technique however
these methods do not specifically address this problem and their efficacy is
controversial."Gcuff" has been designed for multiple purposes such as
impression
making and temporary gingival shaping made from a rigid material and not 3d
designed with cad cam devices which is specific for each implant prosthesis.
[5] The present invention provides a novel method and system to overcome the
commonly occurring problem encountered during the cementation of dental
implant prosthesis, namely excess cement residue on the implant-mucosal
surface.
SUMMARY OF THE INVENTION
[6] The present invention is a device and method to protect the pen-implant
tissue
from excess cement in a cement-retained implant. The present invention is a 3d
meticulously designed protective shield that prevents the penetration of
excess
cement to peri-im plant soft tissues, and it can be used with every implant
system
based on their specific 3d geometry. In addition, it can be customized and can
be
used in mass production as an adjunctive part with different implant systems.
The
solution involves the use of 3D printing technology which simulates and
fabricates
models precisely using a wide variety of materials, ranging from low flexible
to
highly flexible materials.
[7] The protective shield's solution creates a layer that prevents the
penetration of
excess cement to pen-implant soft tissues. The simple, affordable, and
efficient
technique will assist clinicians in combating the issue. The protective
shield's
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application will involve manufacturing a custom flexible and thin protective
shield,
by a 3d printer, upon scanning the abutment and its surrounding tissues and
can
be made specifically for different implant systems with mass production with
any
flexible material with data gathered from 3d specific designs with technology
to
reduce the costs.
[8] The protective shield has a lingual wing facing toward the tongue and a
buccal
wing both having a curvature slightly upward on the distal ends and inverted
ledges on the proximal ends. The shield further has a funnel-shaped circular
opening in the center that extends downwardly to receive the abutment and has
inverted ledges around the funnel which extend circumferentially around the
implant.
[9] The lingual wing and the buccal wing create a shearing part in
connection to each
other so that the shearing part in the funnel and shearing parts on the wings
create a tearing line to guarantee the tearing and removing the excess cement
according to the aspects of the present invention. In addition, the shearing
part
on the wings has V-shaped notches to facilitate the removal of the shield by
tearing that from those areas. In addition, projections are designed to
guarantee
the removal of any remained cement.
[10] The protective shield is easily placed on the abutment from the apical
side to fit
this component intimately. The position of the shield is at least 0.5 mm above
the
switched platform and 0.5 mm below the margin of the abutment, by considering
the oral-facial direction of the shield. Once all these are completed, the
abutment
will be placed into the patient's mouth and tightened on the corresponding
implant. At this point, everything is ready for implementing the cementation
procedure.
[11]After the cementation procedure is completed, any excess cement is pushed
out and any entrapment is prevented as a result of the seal between the
abutment and the shield. When the cementation procedure is complete, the
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Date Recue/Date Received 2022-07-07
shield is pulled out from the oral and facial sides, using a hemostat pliers
to be
torn from the V-shaped notches. It is worth mentioning that the projections on
the weak areas of the shield help in removing any remaining excess cement
from the area.
[12] The protective shield has applications for both bone-level implants and
tissue-
level implants. The main feature involves a funnel-shaped barrier that is
connected to the flat part and made with resilient 3d printed materials to
seal
the area. however, the protective shield will significantly benefit bone-level
implants, due to the subgingival nature of bone-level implants.
[13]Therefore, it is an object of the present invention to provide a system
and
method to prevent dental implant failure due to residual excess cement and
save
money and time for dental implant companies, dentists and patients.
[14] It is another object of the present invention to wave the need for cast
and
abutment itself, as all procedures can be performed on digital data and sent
via
email by a dentist or a dental technician.
[15] It is another object of the present invention to provide the capability
to mass-
produce prefabricated protective shields for different available brands of
implants.
[16] It is another object of the present invention to provide dental
professionals with
an improved prognosis of their patients, for more profitable practices.
[17] it is another object of the present invention that is based on 3d scans
and has
some special features, and it can be made with a resilient material, so the
results
are more accurate than other methods and techniques.
BRIEF DESCRIPTION OF THE DRAWINGS
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[18] Embodiments herein will hereinafter be described in conjunction with the
appended drawings provided to illustrate and not to limit the scope of the
claims,
wherein like designations denote like elements, and in which:
FIG. 1 shows a perspective top view of the bone-level protective shield of the
present invention;
FIG. 2 shows a perspective bottom view of the bone-level protective shield of
the
present invention;
FIG. 3 shows a perspective assembled view of the bone-level protective shield
of the present invention;
FIG. 4 shows a perspective exploded view of the bone-level protective shield
of
the present invention;
FIG. 5 shows a perspective view of the bone-level protective shield of the
present
invention and placement on the abutment;
FIG. 6 shows a perspective view of the protective shield of the present
invention
and the bone level abutment;
FIG. 7 shows a side view of the protective shield of the present invention and
the
bone level abutment;
FIG. 8 shows a diagram of the method of prevention of the penetration of
excess
cement to pen-implant soft tissues for bone-level implants by the bone-level
protective shield of the present invention, and
FIG. 9 shows a diagram of the method of prevention of the penetration of
excess
cement to pen-implant soft tissues for tissue-level implants by the tissue-
level
protective shield of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[19] A protective shield to protect the pen-implant tissue from excess cement
in
cement-retained implants is disclosed. The protective shield has applications
for
both bone-level implants and tissue-level implants, however, it will
significantly
benefit bone-level implants, due to the subgingival nature of bone-level
implants.
Date Recue/Date Received 2022-07-07
[20] According to Figs 1 to 7, a bone level protective shield 10 is
illustrated according
to the present invention. The protective shield 10 comprises a lingual wing 11
facing toward the tongue and a buccal wing 12 facing toward the cheek. The
lingual wing 11 and the buccal wing 12 are placed on an abutment adjacent to
each other building a wing shearing line 16. The protective shield has an
upper
side 10a and a lower side.10b and the wings are curveted slightly upwards on
their distal ends 11a and 12a.
[21] The wings 11 and 12 have a funnel-shaped protrusion 13 on the central
lower
side 10b so that when placed on the abutment 20 adjacent to each other create
a
funnel shape opening to be seated and extended circumferentially around the
abutment 20. The funnel shaped protrusion 13 further has a funnel shearing
line
17 so that the wing shearing line 16 and funnel shearing line 17 are placed
adjacent and build a tearing line.
[22] The wing shearing line 16 has inverted ledges 14a, 14b around the wing
and V-
shaped notches on the mesial and distal ends 18a, 18b. The inverted ledges of
the wing shearing line and the funnel shearing line and the V-shaped notches
on
the mesial and distal end and the funnel shape protrusion create a tearing
line to
tear and remove the excess cement according to the present invention. The
shield
is designed so that the areas ended with V-shaped notches are reduced in
thickness (weak areas) to facilitate the removal of the shield by tearing that
from
those areas. In addition to that, projections are designed above the weak
areas
to guarantee the removal of any remained cement.
[23] According to FIG. 1 again the funnel-shaped part 13 has an inverted ledge
15
around the funnel that extends circumferentially around the implant to remove
excess cement and make it safe to remove without any residue after dental
implant prosthesis cementation procedure.
[24] FIGs. 3 to 7 show the clinical step which involves placement of the
protective
shield 10. The shield 10 is easily placed on abutment 20 from the apical side.
The
placement of the shield 10 is easy and fast due to the funnel shape of the
bone-
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level abutments. The bone-level abutments have a crown margin 22 with an
inverted ledge around the abutment margin 23. The position of the shield 10
must
be at least 0.5 mm below the abutment crown margin 22 so that the funnel part
13 of the protective shield encompasses the abutment cuff 23, and 0.5 mm above
the switched platform 31of the abutment, and by considering the oral-facial
direction of the shield. Once shield 10 is placed on the abutment 20, the
abutment
20 will be placed into the patient's mouth and tightened on the corresponding
implant 30. At this point, everything is ready for implementing the
cementation
procedure. FIG. 3 shows the cement-retained crown 19.
[25] An amount of cement is provided to fix the restoration to an implant
abutment.
Usually, in the cementation procedure, the clinicians place in excess of 20
times
more cement into the crown than is required. This overload of cement means
that
95% is extruded out at the restorative margin, which is frequently found below
the
gum, making cement removal virtually impossible and causing diseases. The
present invention helps the clinician to remove the excess cement and
guarantees
the removal of any remained cement.
[26] Implants have a coronal or gingival end with a threaded bore extending
upwardly.
The coronal end extends downwardly along a cylindrical body to a distal end
and connects to the abutment. The upper part of abutment 21 has a cylindrical
configuration and extends to a bottom part that abuts against the coronal end
of
implant 30. Abutments 20 may be provided with an engaging feature that engages
with the implant 30. The abutment has a crown margin 22 that includes a
shoulder
at the top portion. A corresponding ledge is formed along the exterior surface
adjacent shoulder. The cuff 23 tapers outwardly and upwardly away from the
coronal end of the implant and forms a frusto-conical shape. This tapering
continues to a ledge and then transitions to taper inwardly at the upper
portion of
the cuff. A shoulder is located along the inner surface. This shoulder fits
with the
mating ledge on the exterior of the core. The protective shield is designed to
fit
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Date Recue/Date Received 2022-07-07
tight around the abutment crown margin 22 and seal between abutment 20 and
shield 10.
[27] When the cementation procedure is complete, the shield 10 is pulled out
from the
oral and facial sides, using a hemostat pliers to be torn from the V-shaped
notches
18a, 18b. It is worth mentioning that the projections on the weak areas of the
shield-wing shearing parts 16 and funnel shearing parts 17 help in removing
any
remaining excess cement from the area. The protective shield 10 is made of
flexible material and in various sizes that help the easy removal of the
shield.
[28] Tissue-level implants require the margin of the restoration to be placed
on the
margin of the implant, which is often at the level of the soft tissue. As a
result, it is
less likely for tissue-level implants to have problems with excess cement.
However, if required, the specification of the implant can be used to design
the
apical portion of the protective shield, since the location of the margin is
not
altered. For it to be easily placed, the shield should be manufactured from
more
resilient material to allow for insertion from the top of the implant fixture.
The
height of the apical part should not exceed 1 mm. It is apparent that
producing
prefabricated shields for tissue-level implants is easier than the bone-level
types.
[29] According to FIG. 8 the following steps will be undertaken for bone level
implants
800. In step 801 a scan of the definitive abutment is created. This scan is
performed on the definitive cast while the gingival mask is removed. In step
802
another scan of the definitive abutment is created while the gingival mask is
in
place on the definitive cast. In step 803 the two created scans are
superimposed
on each other. In step 804 the lingual and buccal wings of the protective
shield
are designed from the resulting 3D scans. Then, the other part of the shield
which
is covering the supragingival part of the peripheral soft tissue should now be
designed to create the funnel-shaped part of the protective shield. The amount
of
coverage in the facial and oral sides of the implant should be designed to
surpass
the outline of the crown by 3 millimetres. Additionally, the shield should be
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Date Recue/Date Received 2022-07-07
designed not to interfere with the seating of the restoration. Thus, a
thickness of
0.5 mm is advised for this purpose.
[30] In step 805 the designed protective shield is fabricated from a flexible
material
using a 3D printer. The weak areas (reduced thickness) ended to V-shaped
notches are designed on the mesial and distal parts of the shield to
facilitate
removal of the shield by tearing that from those areas. In addition to that,
projections are designed above the weak areas to guarantee the removal of any
remained cement. When the digital workflow is adopted, the above-mentioned
scanning procedures have often been performed previously, so that the net
invested time for creating the shield would be minimal. Having all the data
from
previously performed scans, the remaining procedures to design the shield
would
be limited to merely determining the periphery of the shield and the place of
the
weak area and related notches.
[31] In step 806 which is the clinical step involves placement of the
protective shield.
It is easily placed on the abutment from the apical side to fit the shield
intimately.
The placement of the shield is easy and fast due to the funnel shape of the
bone-
level abutments. The position of the shield must be in accordance with the
above
specifications - being at least 0.5 mm above the switched platform and 0.5 mm
below the margin of the abutment, and by considering the oral-facial direction
of
the shield. Once all these are completed, the abutment will be placed into the
patient's mouth and tightened on the corresponding implant.
[32] At this point, in step 807, everything is ready for implementing the
cementation
procedure. Any excess cement is pushed out and any entrapment is prevented
as a result of the seal between the abutment and the shield. When the
cementation procedure is complete, in final step 808, the shield is pulled out
from
the oral and facial sides, using hemostat pliers to be torn from the V-shaped
notches. It is worth mentioning that the projections on the weak areas of the
shield
help in removing any remaining excess cement from the area.
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Date Recue/Date Received 2022-07-07
[33] FIG. 9 shows the same procedure for tissue-level Implants. Tissue-level
implants
require the margin of the restoration to be placed on the margin of the
implant,
which is often at the level of the soft tissue. As a result, it is less likely
for tissue-
level implants to have problems with excess cement. However, if required, the
specification of the implant can be used to design the apical portion of the
protective shield, since the location of the margin is not altered. For it to
be easily
placed, the shield should be manufactured from more resilient material to
allow
for insertion from the top of the fixture. The height of the apical part
should not
exceed 1 mm. It is apparent that producing prefabricated shields for tissue-
level
implants is easier than the bone-level types.
[34] The following steps will be undertaken for tissue-level implants 900. In
step 901
a scan of the definitive abutment must be taken. This scan must be performed
on
the definitive cast while the gingival mask is removed. In step 902 another
scan
of the definitive abutment must be created while the gingival mask is in place
on
the definitive cast.
[35] In step 903 the two created scans must be superimposed on each other. The
protective shield is designed from the resulting 3d scans. This shield should
be
designed to cover 1 millimetre below the fixture margin, since it should be
placed
from above so it should be flexible enough to allow a complete seat from
above.
This modelling can be quickly rendered, having the characteristics of each
commercially available fixture. This guides the excess cement out of the
critical
transgingival portion of the implant.
[36] In step 904 the other part of the shield which is covering the
supragingival part of
the peripheral soft tissue should now be designed to create a funnel-shaped
protective shield, extended circumferentially around the implant. The amount
of
coverage in the facial and oral sides of the implant should be designed to
surpass
the outline of the crown by 7 millimetres. Additionally, the shield should be
Date Recue/Date Received 2022-07-07
designed not to interfere with the seating of the restoration. Thus, a
thickness of
0.5 to 1 mm is advised for this purpose.
[37] Shearing areas (reduced thickness) ended with V-shaped shearing notches
designed on the mesial and distal parts of the shield to facilitate removal of
the
shield by tearing that from those areas. In addition to that, inverted ledges
are
designed above the shearing areas to guarantee the removal of any remained
cement.
[38] In step 905 the designed protective shield is fabricated from a flexible
material
using a 3d printer. When the digital workflow is adopted, the above-mentioned
scanning procedures have often been performed previously, so that the net
invested time for creating the shield would be minimal. Having all the data
from
previously performed scans, the remaining procedures to design the shield
would
be limited to merely determining the periphery of the shield and the place of
the
weak area and related notch.
[39] This clinical step 906 involves the placement of a protective shield. It
is easily
placed on the abutment from the corona! (top) side to fit this component
intimately
and it should snap on the fixture collar to place just 0.5 mm below the
margin. The
placement of the shield is easy and fast due to the flexibility of the
protective
shield.
[40] At this point, in step 907 everything is ready for the cementation
procedure. Any
excess cement is pushed out and any entrapment is prevented because of the
seal between the fixture and the shield. When the cementation procedure is
complete, in step 908 the shield is pulled out from the oral and facial sides,
using
hemostat pliers while the patient firmly bites on the cotton roll to be torn
from the
V-shaped notches. It is worth mentioning that the inverted ledges on the
shield's
weak areas help remove any remaining excess cement from the area.
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Date Recue/Date Received 2022-07-07
[41] For mass production, 3d data gathered can be used from previous scans for
each
specific implant system and can be used to make multiple instances of
protective
shields in different sizes. The shields can be customized for each abutment as
a
kit.
[42] The foregoing is considered illustrative only of the principles of the
invention.
Further, since numerous modifications and changes will readily occur to those
skilled in the art, it is not desired to limit the invention to the exact
construction
and operation shown and described, and accordingly, all suitable modifications
and equivalents may be resorted to, falling within the scope of the invention.
[43] With respect to the above description, it is to be realized that the
optimum
relationships for the parts of the invention regarding size, shape, form,
materials,
function and manner of operation, assembly and use are deemed readily apparent
and obvious to those skilled in the art, and all equivalent relationships to
those
illustrated in the drawings and described in the specification are intended to
be
encompassed by the present invention.
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