Note: Descriptions are shown in the official language in which they were submitted.
COMPOSITION AND METHOD FOR ENDODONTIC DEBRIDEMENT
[0001] [Intentionally left blank].
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] Provided herein are composition, methods, and kits for endodontic
debridement.
[0003] More particularly, provided herein are compositions and kits including
trichloroacetic
acid, and methods of using the same for performing debridement and/or
pulpectomies associated
with endodontic treatment.
Description of Related Art
[0004] It is well-established that the most challenging aspect of root canal
treatment is complete
debridement and clearing of debris and tissue from the root canal system
following endodontic
access. Known solutions are replete with shortcomings.
[0005] Sodium hypochlorite is the current "gold standard" solution for use in
debridement
during endodontic treatment. Sodium hypochlorite digests soft tissue and
disinfects the
surrounding area. However, the mechanism of action of sodium hypochlorite is
incredibly slow,
taking 10 or more minutes to dissolve dental pulp, even at a strength of
6.25%. In addition, sodium
hypochlorite is viscous, limiting its ability to access fins, anastomoses, and
accessory canals.
Further, sodium hypochlorite is unable to dissolve exogenous materials from
prior treatments that
may be present within the root canal.
[0006] Like sodium hypochlorite, EDTA, chlorhexidine, and alcohol are
similarly lacking in
strength and ability to access all areas of the root canal to be effective.
[0007] Accordingly, there is a need in the art for an effective, yet safe,
composition for use in
debridement during endodontic treatment.
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Date Recue/Date Received 2021-09-29
SUMMARY OF THE INVENTION
[0008] Provided herein is a method of dehydrating root canal pulp including
the step of
administering, to dental pulp within the mouth of a patient, a composition
including trichloroacetic
acid, the composition optionally including one or more buffers or excipients.
[0009] Also provided herein is a method of performing endodontic treatment,
including the
steps of performing endodontic access, performing coronal flaring, thereby
opening one or more
root canals and exposing dental pulp within the one or more canals, applying a
composition
comprising trichloroacetic acid to the exposed dental pulp, the composition
optionally including
one or more buffers or excipients, cleaning and shaping the one or more root
canals, applying a
composition including trichloroacetic acid, the composition optionally
including one or more
buffers or excipients, to the one or more cleaned and shaped root canals,
flushing the one or more
root canals with a first flushing solution, and drying the one or more root
canals.
[0010] Also provided herein is a kit including a syringe having a barrel with
a proximal end, a
distal end, and a sidewall therebetween defining a reservoir and a
longitudinal axis, a plunger
received at least partially within the reservoir, and a metal needle tip
attached to the distal end of
the syringe barrel, wherein at least a portion of the needle tip is disposed
at an angle relative to the
longitudinal axis of the barrel, and a composition including trichloroacetic
acid received within
the reservoir.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. I is a schematic view of a device for holding and delivering a
composition for
endodontic debridement according to one non-limiting aspect of the present
invention;
[0012] FIG. 2 is a perspective view of a device for holding and delivering a
composition for
endodontic debridement according to one non-limiting aspect of the present
invention;
[0013] FIG. 3 is a perspective view of a device for holding and delivering a
composition for
endodontic debridement according to one non-limiting aspect of the present
invention;
[0014] FIG. 4 is a side view of a device for holding and delivering a
composition for endodontic
debridement according to one non-limiting aspect of the present invention;
[0015] FIG. 5 is a side view of a device for holding and delivering a
composition for endodontic
debridement according to one non-limiting aspect of the present invention;
[0016] FIG. 6 is perspective view of a needle assembly of a device for holding
and delivering a
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composition for endodontic debridement according to one non-limiting aspect of
the present
invention;
[0017] FIG. 7 is a radiograph of a tooth on which endodontic treatment was
performed without
a composition according to one non-limiting aspect of the present invention;
and
[0018] FIG. 8 is a radiograph of a tooth on which endodontic treatment was
performed with a
composition according to one non-limiting aspect of the present invention.
DESCRIPTION OF THE INVENTION
[0019] The following description is merely exemplary in nature and is in no
way intended to
limit the invention, its application, or uses. While the description is
designed to permit one of
ordinary skill in the art to make and use the invention, and specific examples
are provided to that
end, they should in no way be considered limiting. It will be apparent to one
of ordinary skill in
the art that various modifications to the following will fall within the scope
of the appended claims.
The present invention should not be considered limited to the presently
disclosed aspects, whether
provided in the examples or elsewhere herein.
[0020] The use of numerical values in the various ranges specified in this
application, unless
expressly indicated otherwise, are stated as approximations as though the
minimum and maximum
values within the stated ranges are both preceded by the word "about". In this
manner, slight
variations above and below the stated ranges (e.g., 10%, 9%, 8%, 7%, 6%, 5%,
4%, 3%, 2%,
1%, or 0.5%) can be used to achieve substantially the same results as values
within the ranges.
Also, unless indicated otherwise, the disclosure of ranges is intended as a
continuous range
including every value between the minimum and maximum values. As used herein
"a" and "an"
refer to one or more.
[0021] As used herein, the term "patient" or "subject" refers to members of
the animal kingdom
including but not limited to, human beings and "mammal" refers to all mammals
including, but
not limited, to human beings.
[0022] As used herein, the "treatment" or "treating" of a wound or defect
means administration
to a patient by any suitable dosage regimen, procedure, and/or administration
route an amount of
a composition, device or structure effective to, and with the object of
achieving a desirable
clinical/medical end-point, including attracting progenitor cells, healing a
wound, correcting a
defect, etc.
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[0023] As used herein, the terms "comprising," "comprise" or "comprised," and
variations
thereof, are open ended and do not exclude the presence of other elements not
identified. In
contrast, the term "consisting of' and variations thereof is intended to be
closed and excludes
additional elements in anything but trace amounts.
[0024] As used herein, "endodontic treatment", or "endodontic therapy", refers
to the procedure
commonly known as "root canal therapy." As used herein, "endodontic treatment-
refers to one
or more steps of removing pulp from the space inside of a tooth, cleaning,
disinfecting, and shaping
the root canal, and filling the space.
[0025] Provided herein are compositions and kits including trichloroacetic
acid (TCA), and
methods of using the same in endodontic treatment. The following disclosure
will exemplify TCA,
and, in particular, 90% TCA. However, those of skill in the art will
appreciate that acids of a
similar mass (e.g., a molar mass of ¨ 160 g-m01-1) and strength (e.g., a pKa
of ¨ 0.6) will be useful
for debridement during endodontic treatment as described herein. In
particular, as TCA is a
derivative of acetic acid, other derivatives of acetic acid (e.g.,
chloroacetic acid, dichloroacetic
acid, trifluoroacetic acid, and tribromoacetic acid) are expected to be
similarly useful, as are other
simple carboxylic acids (e.g., C 1 -C4 carboxylic acids). In some aspects, a
composition as
described herein can optionally, in non-limiting aspects, include one or more
excipients or carriers.
An excipient is an inactive substance used as a carrier for the active
ingredients of a composition.
Although "inactive," excipients may facilitate and aid in increasing the
delivery, stability, or
bioavailability of an active ingredient in a composition. Excipients include
antiadherents, binders,
rheology modifiers, coatings, emulsifiers, oils, buffers, salts, acids, bases,
fillers, diluents,
solvents, colorants, glidants, lubricants, preservatives, antioxidants,
sorbents, vitamins, etc., as are
available in the pharmaceutical/compounding arts (see, generally, Troy, DB,
Editor, Remington:
The Science and Practice of Pharmacy, 21st Ed., Lippincott Williams & Wilkins
(2005) for a
discussion of pharmaceutically-acceptable carriers and excipients). However,
in other aspects, the
composition consists essentially of, or consists only of, trichloracetic acid.
[0026] A composition as described herein can include, in some aspects, about
90% trichloracetic
acid, including in some aspects 90% trichloracetic acid. However, in other
aspects, the TCA is
about 50%, about 60%, about 70%, about 80%, or about 100% TCA, all percentages
and subranges
therebetween inclusive.
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[0027] Also, provided herein are kits including TCA and a mechanism or device
for delivering
TCA during endodontic treatment. In some aspects, the mechanism or device is a
syringe, as is
known in the art. Useful syringes can be formed of a glass or plastic barrel
having a proximal end,
a distal end, and a sidewall therebetween defining a reservoir for holding a
composition (e.g., TCA
as described herein). A mechanism or device useful for delivering TCA or other
suitable acid, for
example and without limitation a syringe, can be sized as appropriate. In non-
limiting aspects, the
device is of a similar size as an endodontic hand file (e.g., 21 mm ¨ 31 mm in
length, all lengths
and sub-ranges therebetween inclusive). As known in the art, syringes also
include plungers for
delivering a composition held within the reservoir through a needle arranged
(via either permanent
or reversible connections) at the distal end of the syringe. As is known in
the art, plungers can be
formed of any useful material, including plastic. Needles of any suitable
gauge and length can be
used in the kit of the present invention. In some aspects, the needle is a 30-
gauge needle. In some
aspects, the needle is about 10 mm to about 15 mm in length.
[0028] A device suitable for delivering TCA during endodontic treatment can be
of any suitable
shape or configuration to allow for precise delivery while minimizing
accidental or extraneous
delivery of TCA to tissues other than the target. For example, and without
limitation, suitable
devices can be angled (e.g., the barrel and/or the needle) to allow for
precision delivery, to improve
comfort, and/or to minimize fatigue during use. In such aspects, the syringe
barrel can be suitably
angled, the syringe needle can be suitably angled, or both. In other aspects,
the syringe (barrel
and/or needle) can be straight. In further non-limiting aspects, the syringe
needle includes one or
more side vents to control delivery and, for example and without limitation,
to prevent gross apical
extrusion, that is, extrusion of TCA beyond the area of treatment to a vital
structure, such as, for
example and without limitation, the mandibular nerve.
[0029] Because of the strength of TCA (or other suitable acids useful in the
methods described
herein), it is advantageous, in some aspects, that the mechanism or device
(e.g., syringe) not
include components that are susceptible to being dissolved by TCA (or acids
having a similar or
higher pKa as compared to TCA). Thus, in some aspects, a device included in a
kit as described
herein does not include any rubber components that would be in contact with
the reservoir (and
the acid compositions held within the reservoir). In further aspects, the
device does not include
plastic in any component that would come in contact with TCA, or includes only
suitable plastics
that are known to not degrade, or to degrade only minimally, when in contact
with acids having a
Application.DOCX
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similar pKa to TCA. In some non-limiting aspects, the barrel of the device is
at least partially
formed from glass, which will not degrade during prolonged contact with TCA.
[0030] In some aspects, the syringe and plunger are arranged or configured
such that discrete,
known aliquots of the composition held within the reservoir can be dispensed.
In some non-
limiting aspects, stops arranged on the syringe barrel and/or the plunger
shaft are provided to allow
for the precise delivery of only the desired aliquot. Technology for allowing
for repeated delivery
of known aliquots is known, for example, repeating dispensers sold
commercially by Hamilton
Robotics (Reno NV), Restek (Bellefonte PA), as well as self-refilling syringes
from DWK Life
Sciences (Millville NJ). In some aspects, the syringe and/or plunger are
configured such that
aliquots of about 0.3 ml, about 0.4 ml, about 0.5 ml, about 0.6 ml, about 0.7
ml, or about 0.8 ml
(all volumes and sub-ranges therebetween inclusive) of TCA can be delivered
during endodontic
treatment. Those of skill in the art will appreciate that syringes/plungers
can be configured to
deliver other desired aliquots that would be useful in various aspects of
endodontic treatment, and
that such configurations fall within the scope of the invention described
herein.
[0031]
FIG. 1 shows a non-limiting aspect of a mechanism or device 100 suitable for
delivery
of TCA, or other suitable acid, during endodontic treatment as described
herein. In the illustrated
non-limiting aspect, the device is a syringe-like device 100 capable of
holding one or more aliquots
of TCA or other suitable acid. In the illustrated embodiment, device 100
includes a barrel having
two portions 110, 120, a plunger 130, and a needle 140. Device 100 includes in
the interior of
barrel, in reservoir 150, one or more aliquots of TCA 160. As described above,
the aliquots can
be of any useful volume for endodontic treatment. The illustrated aspect
includes a syringe barrel
having an angle between portions 110 and 120 to increase access and precise
delivery to the target
area during endodontic treatment. As described above, in aspects the barrel
can be formed of two
different materials. For example, and without limitation, barrel portion 110
can be formed of
plastic, or other material that is cost-effective, and that would degrade with
prolonged contact with
TCA 160, and barrel portion 120 can be formed of glass or other material that
will not degrade, or
will degrade only inconsequentially, when placed in contact with TCA 160 for
extended periods
of time. Similarly, needle 140 can be formed of a material that does not
degrade when in contact
with TCA 160. While needle 140 is shown with a blunted tip, those of skill in
the art will
appreciate that any useful shape could be adopted. The illustrated aspect
further includes side
vents 170 in the syringe needle 140 to improve delivery control.
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[0032] Turning to FIGS. 2-5, shown is another non-limiting aspect of a
mechanism or
device 200 suitable for delivery of TCA, or other suitable acid, during
endodontic treatment as
described herein. In the illustrated non-limiting aspect, the device 200 is a
syringe-like device
capable of holding one or more aliquots of TCA or other suitable acid. While
the embodiment
illustrated in FIGS. 2-5 show a device with a removable or replaceable ampule
230, those of
ordinary skill in the art will appreciate that a device suitable for delivery
of TCA or other suitable
acid can be a single use, pre-filled device. Device 200 includes a barrel 210
and, in embodiments
in which the device is reusable, an opening or window 220 to allow for the
insertion and removal
of an ampule 230. A useful ampule 230 can include a stopper 235 on which a
proximal
portion 252 of plunger rod 250 can act to expel TCA or other suitable acid
from the ampule 230
and through the syringe needle 270. Ampule 230, including stopper 235, can be
formed of any
useful material that does not corrode with prolonged contact with TCA or other
acid(s) of similar
strength. Device 200 includes a gripping arrangement 240, shown in FIGS. 2-5
as finger grips, to
allow for the device to be manipulated for delivery of TCA to regions within a
patient's mouth.
Plunger 250 can include at a proximal end thereof 254 a thumb pad for
actuation.
[0033] Device 200 also includes a needle 270 to allow the TCA, or other
suitable acid, to be
delivered to target area(s) within a patient's mouth. In the embodiment
illustrated in FIGS. 2-6,
needle 270 is angled with respect to a longitudinal axis of the syringe barrel
210. Those of skill in
the art will appreciate that the location at which the needle is angled can
vary. For example, as
shown in FIGS. 2-6, needle is angled substantially at a point of connection to
needle hub 265.
However, in other aspects, needle 270 can be coaxial with the longitudinal
axis of syringe
barrel 210 for a substantial, e.g., 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or
90% (all ranges
and values therebetween inclusive), of the length of the needle 270, and that
the angle can be
implemented at various regions to account for different targets within the
mouth. In non-limiting
aspects (not shown with respect to the aspect of FIG. 2), the needle can be
straight or substantially
straight, that is, coaxial with the syringe barrel 210. With continuing
reference to FIGS. 2-6,
device 100 includes needle 270, which can be affixed to syringe barrel 210 or
can be a removable
and replaceable needle assembly 260. In either aspect, a needle assembly 260
can include a needle
hub 265 and needle 270. Needle hub 265 can, as described above, be permanently
affixed to
syringe barrel 210 or removable therefrom. Removable needle hubs can include
those with luer
connections to enable connection to a syringe barrel, or any other useful
connection known to those
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of skill in the art. In non-limiting aspects, needle 270 can include one or
more vents 275 in a
sidewall thereof, to control delivery and, for example and without limitation,
to prevent gross
apical extrusion. While the vent 275 in FIGS. 2-6 is shown at a distal end of
the needle (further
from the syringe barrel), those of skill in the art will appreciate that the
location and number of the
vent(s) can be modified similar to the manner that the overall
arrangement/shape of the needle can
be modified, in order to, for example, accommodate different anatomies.
[0034] Also provided herein are methods of digesting root canal pulp,
performing pulpectomies,
and debriding wounds during endodontic treatment. The methods include
delivering,
administering, or otherwise contacting dental pulp with a composition
including TCA, as described
herein. As described above, in aspects the composition can include suitable
excipient(s) or
carrier(s), or, in other aspects, can consist essentially of or consist only
of TCA (e.g., 90% TCA).
In some aspects, the TCA is aqueous TCA.
[0035] In some aspects of methods as described herein, the TCA is aqueous and
is delivered to
the root canal, in some aspects the pulp chamber floor of a tooth, as an
irrigation fluid. In some
aspects, a syringe or other fluid-dispensing device (as described herein) is
used to deliver the fluid.
In other aspects, a solution including TCA (and, optionally, one or more
excipient(s) or carrier(s)
as described herein) is absorbed into, adsorbed on, or impregnated into a
solid or semi-solid carrier
as is known in the dental arts. In some aspects, the carrier is an absorbent
paper, gauze, or the like
that allows for placement into a desired area (e.g., the root canal, in
contact with the pulp chamber
floor, etc.) and simple removal from the same area.
[0036] As noted above, a shortcoming of known debridement methods is the
relatively
prolonged amount of time that the treatment must be used. In contrast to, for
example, sodium
hypochlorite (10 minutes), methods as described herein require contact between
the pulp and the
composition including TCA for much shorter periods of time. In some aspects,
the composition
described herein is placed in contact with the pulp to dehydrate and render
the pulp more
susceptible to dissolution by another composition, for example and without
limitation, sodium
hypochlorite. Without wishing to be bound by the theory, a mechanism of action
of TCA in
endodontic treatment is believed to include dehydration of pulp, which results
in a shrinking of
pulp volume, resulting in a "pulling back" of pulp from dentin walls. This
change in the
volume/configuration of the pulp is believed to allow for more thorough access
of sodium
hypochlorite to the pulp, increasing dissolution of pulp by the sodium
hypochlorite. Again,
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without wishing to be bound by the theory, addition of sodium hypochlorite to
TCA at the site of
endodontic treatment is believed to produce chlorine gas and water, which
results in
bubbling/foaming. The chlorine gas is believed to play an antibiotic role at
the site of treatment,
and the water that is produced is a harmless end product of the chemical
reaction. In some aspects,
the TCA is maintained in contact with the pulp for five minutes or fewer, four
minutes or fewer,
three minutes or fewer, two minutes or fewer, or one minute or fewer (though
more than zero
seconds), all times and subranges therebetween inclusive.
[0037] Also provided herein is a method of performing endodontic treatment,
using a
composition and, optionally, a kit as described herein. In aspects, the method
includes the step of
performing endodontic access to access the pulp chamber. Following access, in
some aspects,
coronal flaring is performed to open up at least one of the root canals. In
some aspects, at this
point TCA is applied to the pulp chamber floor and/or one or more of the root
canals. In some
aspects, with one or more appropriate dental or endodontic tools, the
composition is dispersed
toward the apex to promote/maintain apical patency. In some aspects, the
application of TCA is
followed by optional flushing or washing, optionally with sodium hypochlorite,
and, optionally,
additional application of sodium hypochlorite. As noted above, without wishing
to be bound by
the theory, it is believed that application of TCA dehydrates pulp, rendering
the pulp more
susceptible to thorough dissolution by sodium hypochlorite. Further, as the
reaction of TCA and
sodium hypochlorite results in production of water, in some aspects it is not
necessary to perform
a separate flushing/washing step (however, in aspects, the water that is
produced through the
reaction of TCA and sodium hypochlorite is washed/flushed from the site of
treatment, and fresh
sodium hypochlorite is applied). In some aspects, these steps (applying TCA
and, optionally,
dispersing the same) are performed one or more times. In some aspects, the
steps of applying TCA
and washing/flushing, optionally with sodium hypochlorite, followed by
optional additional
application of sodium hypochlorite) are repeated one or more times until the
pulp has been
dissolved. In some aspects, as described above, the composition including TCA
is maintained in
contact with the pulp for five minutes or fewer, four minutes or fewer, three
minutes or fewer, two
minutes or fewer, or one minute or fewer (though more than zero seconds) per
application, all
times and subranges therebetween inclusive
[0038] Thereafter, the root canals are cleaned and shaped according to methods
known to those
of skill in the art. Following root canal cleaning/shaping, in some aspects, a
composition including
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TCA is introduced to the root canal, in some aspects, with a solid or semi-
solid carrier, such as an
absorbent paper or gauze, to further dehydrate any possible remaining unwanted
tissue, followed
by application of sodium hypochlorite. Thereafter, the root canal is flushed
to remove the TCA
and/or sodium hypochlorite and prepare the root for filling. As noted above,
as the reaction of
TCA and sodium hypochlorite results in production of water, in some aspects it
is not necessary
to perform a washing step. In some aspects the root canal is flushed with one,
two, three, four, or
more different flushing solutions. Flushing solutions are known to those of
skill in the art, and
include, without limitations, sodium hypochlorite, EDTA, chlorhexidine,
alcohol, and chloroform.
In some aspects, the flushing solutions are one or more of sodium
hypochlorite, EDTA (e.g., 17%
EDTA), and one or more alcohols. In some aspects, the flushing solutions are
introduced (and
removed) in a specific order: sodium hypochlorite, alcohol, EDTA, and alcohol.
In non-limiting
aspects, the alcohol utilized for a final flush is isopropanol, ethyl alcohol,
and/or absolute alcohol.
Thereafter, the root canal is dried, optionally with paper points, and filled
as is known in the art
(e.g., with gutta-percha).
100391 In non-limiting aspects, a protocol for performing endodontic access
includes
performing endodontic access to access the pulp chamber. Following access, in
some aspects,
coronal flaring is performed to open up at least one of the root canals. In
some aspects, at this
point TCA is applied to the pulp chamber floor and/or one or more of the root
canals. In some
aspects, with one or more appropriate dental or endodontic tools, the
composition is dispersed
toward the apex to promote/maintain apical patency. In some aspects, the
application of TCA is
followed by flushing with sodium hypochlorite. In embodiments or aspects in
which endodontic
treatment requires or would benefit from more than one visit (e.g., in the
case of necrotic pulp), a
temporary sealing material and/or temporary filling material, for example
those described below,
for example calcium hydroxide, can be applied to the canal. Then, at a
subsequent visit, TCA can
be used to dissolve and/or remove the temporary sealing material and/or
temporary filling material.
Thereafter, in aspects, the root canals are optionally flushed and are then
cleaned and shaped
according to methods known to those of skill in the art. Following root canal
cleaning/shaping,
the root canal is flushed with EDTA to prepare the root for filling. In
aspects, following flushing
with EDTA, the root canal is flushed with an alcohol (isopropanol, ethyl
alcohol, and/or absolute
alcohol). Thereafter, the root canal is dried, optionally with paper points,
and filled as is known
in the art
Application.DOCX
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[0040] Experiments with TCA show that the use of such compositions provides
improved access
of a debridement composition to microscopic root canal branches, fins, and
anastomoses. More
specifically, use of TCA in endodontic treatment including sodium hypchlorite
results in a cleaner
apex, lessened bleeding or elimination of bleeding altogether, reduced pain
(for example as shown
below in the Example), particularly in lower molar cases, and less
inflammation (again,
particularly in lower molar cases). These features, for example increased
access and a cleaner
apex, result in a far cleaner root canal, removal of smaller amounts of dentin
during the endodontic
treatment, and superior healing and success of the endodontic treatment. FIGS.
2 and 3 show
radiographic images from prior to (FIG. 2) and following (FIG. 3) endodontic
treatment with a
TCA composition as described herein. The image in FIG. 2 is of a tooth that
had previously
undergone endodontic treatment, but without TCA as a debridement solution. As
can be seen, the
tooth in FIG. 2 shows a poorly-cleaned root with low density and an absence of
irregular
deformation (also known as corkage). In contrast, as shown in FIG. 3, after
endodontic treatment
with TCA, the retreated root shows a thicker irregular deformed material that
fully fills the root
tip.
[0041] Another notable effect of treatment with TCA is improved removal of
debris, such as
dentin debris, as well as material from prior endodontic treatment, either
during retreatment cases,
or temporary sealing and/or filling material from prior preparatory visits,
for example where
endodontic treatment may require several visits to complete (e.g., in the case
of necrotic pulp).
FIGS. 7 and 8 show radiographic images from prior to (FIG. 7) and following
(FIG. 8)
endodontic treatment with a TCA composition as described herein. The image of
FIG. 7 is of a
tooth that had previously undergone endodontic treatment, but without TCA as a
debridement
solution. As can be seen, the tooth in FIG. 7 shows a poorly-cleaned root with
low density and an
absence of irregular deformation (also known as corkage). In contrast, as
shown in FIG. 8 after
endodontic treatment with TCA, the retreated root shows a thicker irregular
deformed material that
fully fills the root tip.
[0042] For example, when endodontic treatment may require several visits, an
approach can be
to fill the canal with an intracanal medicament, a sealing material, and/or a
filling material, such
as calcium hydroxide, mineral trioxide aggregate, zinc oxide eugenol, glass
ionomers, various
plastics (e.g., thermoplastic polyesters), rubbers (natural and/or synthetic),
dentin (e.g.,
hydroxyapatite crystalline debris), resins (e.g., methacrylate-based resins),
tricalcium silicate, and
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ceramics (e.g., bioceramics including those containing alumina, zirconia,
bioactive glass, glass
ceramics, hydroxyapatite, and/or calcium phosphates). In non-limiting
embodiments or aspects,
the intracanal medicament, sealing material, and/or filling material is sodium
hydroxide, which is
a bacteriostatic material that alters the pH of the environment into which it
is placed to deter
bacterial growth. In non-limiting embodiments or aspects, the intracanal
medicament, sealing
material, and/or filling material is softened, removed, and/or dissolved by
application of TCA, as
described herein, to the medicament and/or material. In non-limiting
embodiments or aspects, the
TCA is applied to the medicament and/or material for not more than five
minutes, preferably not
more than four minutes, preferably not more than three minutes, most
preferably not more than
two minutes.
[0043] In addition, in terms of retreatment, typically the standard in the
field is to use chloroform
to remove prior materials, such as gutta-percha, various plastics (e.g.,
thermoplastic polyesters),
mineral trioxide aggregate, calcium hydroxide, zinc oxide eugenol, glass
ionomers, rubbers
(natural and/or synthetic), dentin (e.g., hydroxyapatite crystalline debris),
resins (such as those
described above), tricalcium silicate, and ceramics (such as those described
above). However,
chloroform use can be associated with undesirable side effects, such as
necrosis at the site of
treatment. Trichloroacetic acid represents an optional approach during
retreatment cases.
Accordingly, in non-limiting embodiments or aspects, provided herein is a
method of performing
endodontic retreatment, including the steps of performing endodontic
retreatment to access the
prior sealing and/or filling material, such as those described above.
Following access, in some
aspects, coronal flaring is performed to open up at least one of the root
canals. In some aspects,
TCA is applied to the prior filling material. In other aspects, TCA is applied
after treatment of the
prior filling material with chloroform. In some aspects, these steps (applying
TCA (optionally
after application of chloroform) and dispersing the same) are repeated one or
more times until the
prior material has been dissolved. In some aspects, after access, chloroform
is applied to the prior
filling material, followed by a washing/drying with alcohol (useful alcohols
are described herein),
then application of TCA.
[0044] Thereafter, the root canal(s), if present, can be cleaned and shaped
according to methods
known to those of skill in the art. Following root canal cleaning/shaping, in
some aspects, a
composition including TCA is introduced to the root canal, in some aspects,
with a solid or semi-
solid carrier, such as an absorbent paper or gauze, to further dissolve any
possible remaining
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unwanted tissue or material. Thereafter, the root canal is flushed to remove
the TCA and prepare
the root for filling. In some aspects the root canal is flushed with one, two,
three, four, or more
different flushing solutions. Flushing solutions are known to those of skill
in the art, and include,
without limitations, sodium hypochlorite, EDTA, chlorhexidine, alcohol, and
chloroform. In some
aspects, the flushing solutions are one or more of sodium hypochlorite, EDTA
(e.g., 17% EDTA),
and one or more alcohols, as described above. In some aspects, the flushing
solutions are
introduced (and removed) in a specific order: sodium hypochlorite, alcohol,
EDTA, and alcohol.
Thereafter, the root canal is dried and filled as described above.
Example
[0045] Use of TCA during endodontic treatment is associated with decreased
incidence of pain
following endodontic treatment. Without wishing to be bound by the theory, it
is believed that the
TCA composition eliminates unmyelinated C fibers in the apical pulp,
particularly in mandibular
molars. To assess the decreased pain, individuals were asked to provide a self-
assessment, on a
scale of 1-10, of pain prior to endodontic treatment, and 6, 24, 48, and 120
hours following
endodontic treatment. Patients were divided into two groups, one group
(Control, N=9) receiving
standard endodontic treatment including sodium hypochlorite as the primary
irrigant, with
occasional (as necessary) flushes with 17% EDTA, and one group (Experimental,
N=10) receiving
endodontic treatment including the composition described herein as a pre-
treatment applied to pulp
to facilitate navigating calcified canals and after initial shaping with
patency. The experimental
group received sodium hypochlorite irrigation and, as necessary, EDTA
flushing, as in the control
group. Results are shown in Table 1 below.
Table 1
Before 6 hours 24 hours 48 hours 120 hours
Control 2.67 1 0.89 1.44 0.56
Experimental 3.1 0.7 0.5 0.4 0.2
[0046] As can be seen, use of the composition described herein reduced
subjective levels of pain
following endodontic treatment compared to the current "gold standard"
control, sodium
hypochlorite.
[0047] A more granular review of the data shows that the composition described
herein is
particularly useful in reducing pain in patients presenting with necrosis at
the time of treatment.
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Patients presenting with necrosis self-reported a pain level of 4.5 before
treatment, and pain levels
of 0.5, 0.25, 0, and 0 at 6, 24, 48, and 120 hours following treatment,
respectively.
[0048] The following clauses are illustrative of the various aspects of the
present invention:
[0049] Clause 1: A method of dehydrating root canal pulp comprising
administering, to dental
pulp within the mouth of a patient, a composition comprising trichloroacetic
acid (TCA), the
composition optionally including one or more buffers or excipients.
[0050] Clause 2: The method of clause 1, wherein the composition consists
essentially of TCA.
[0051] Clause 3: The method of clause 1, wherein the composition consists of
TCA.
[0052] Clause 4: The method of clause 1, wherein the composition consists of
90% TCA.
[0053] Clause 5: The method of any of clauses 1-4, further comprising a step
of administering
sodium hypochlorite to the pulp until all the pulp has been dissolved, wherein
the TCA is applied
for not more than five minutes, preferably not more than four minutes,
preferably not more than
three minutes, most preferably not more than two minutes.
[0054] Clause 6: The method of any of clauses 1-5, wherein the composition
comprising TCA
is applied as an irrigation fluid.
[0055] Clause 7: The method of any of clauses 1-5, wherein the composition
comprising TCA
is absorbed or impregnated in a carrier, and the carrier is applied to the
dental pulp.
[0056] Clause 8: The method of clause 7, wherein the carrier is an absorbent
paper, gauze, or
other absorbent material that can hold the composition.
[0057] Clause 9: A method of debriding a wound during endodontic treatment,
comprising
applying TCA to the pulp chamber floor within a root canal within the mouth of
a patient.
[0058] Clause 10: The method of clause 9, wherein the composition consists
essentially of TCA.
[0059] Clause 11: The method of clause 9, wherein the composition consists of
TCA.
[0060] Clause 12: The method of clause 9, wherein the composition consists of
90% aqueous
TCA.
[0061] Clause 13: The method of any of clauses 9-12, further comprising a step
of administering
sodium hypochlorite to the pulp chamber floor until all pulp has been
dissolved, wherein the TCA
is applied for not more than five minutes, preferably not more than four
minutes, preferably not
more than three minutes, most preferably not more than two minutes.
[0062] Clause 14: The method of any of clauses 9-13, wherein the composition
comprising TCA
is applied as an irrigation fluid.
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[0063] Clause 15: The method of any of clauses 9-13, wherein the composition
comprising TCA
is absorbed or impregnated in a carrier, and the carrier is applied to the
pulp chamber floor.
[0064] Clause 16: The method of clause 15, wherein the carrier is an absorbent
paper, gauze, or
other absorbent material that can hold the composition.
[0065] Clause 17: A method of performing endodontic treatment, comprising: a.
performing
endodontic access; b. performing coronal flaring, thereby opening one or more
root canals and
exposing dental pulp within the one or more canals; c. applying a composition
comprising TCA to
the exposed dental pulp, the composition optionally including one or more
buffers or excipients;
d. applying a composition comprising sodium hypochlorite to the exposed dental
pulp; e. cleaning
and shaping the one or more root canals; f. optionally applying a composition
comprising TCA,
the composition optionally including one or more buffers or excipients, to the
one or more cleaned
and shaped root canals; g. flushing the one or more root canals with a first
flushing solution; and
h. drying the one or more root canals, optionally with one or more paper
points.
[0066] Clause 18: The method of clause 17, further comprising, after applying
the composition
comprising TCA to the exposed dental pulp, a step of dispersing the
composition toward an apex
of the one or more root canals.
[0067] Clause 19: The method of clause 17 or clause 18, further comprising
repeating the steps
of applying the composition comprising TCA to the exposed dental pulp and
dispersing the
composition one or more times, preferably until apical patency is established.
[0068] Clause 20: The method of any of clauses 17-19, further comprising,
after flushing the
one or more root canals with a first flushing solution, flushing the one or
more root canals with a
second flushing solution.
[0069] Clause 21: The method of clause 20, further comprising, after flushing
the one or more
root canals with a second flushing solution, flushing the one or more root
canals with a third
flushing solution.
[0070] Clause 22: The method of clause 21, further comprising, after flushing
the one or more
root canals with a third flushing solution, flushing the one or more root
canals with a fourth
flushing solution.
[0071] Clause 23: The method of any of clauses 17-22, wherein the first
flushing solution
comprises sodium hypochlorite.
[0072] Clause 24: The method of any of clauses 20-23, wherein the second
flushing solution
Application.DOCX
Date Recue/Date Received 2021-09-29
comprises an alcohol.
[0073] Clause 25: The method of any of clauses 21-24, wherein the third
flushing solution
comprises EDTA, preferably 17% EDTA.
[0074] Clause 26: The method of any of clauses 22-25, wherein the fourth
flushing solution
comprises an alcohol, optionally isopropyl alcohol, ethyl alcohol, and/or
absolute alcohol.
[0075] Clause 27: The method of any of clauses 17-26, wherein the composition
comprising
TCA consists essentially of TCA
[0076] Clause 28: The method of any of clauses 17-26, wherein the composition
comprising
TCA consists of 90% TCA.
[0077] Clause 29: The method of any of clauses 17-28, wherein step c. is
performed for more
than five minutes, preferably not more than four minutes, preferably not more
than three minutes,
most preferably not more than two minutes for at least one minute.
[0078] Clause 30: The method of any of clauses 17-29, wherein in step c. the
composition
comprising TCA is applied to the dental pulp as an irrigation fluid.
[0079] Clause 31: The method of any of clauses 17-30, wherein in step f. the
composition
comprising TCA is applied to the cleaned and shaped one or more root canals
with a carrier.
[0080] Clause 32: The method of clause 31, wherein the carrier is an absorbent
paper, gauze, or
other absorbent material that is configured to hold a quantity of the
composition.
[0081] Clause 33: A kit comprising: a syringe comprising: a barrel comprising
a proximal end,
a distal end, and a sidewall therebetween defining a reservoir; a plunger
received at least partially
within the reservoir; and a metal needle tip attached to the distal end of the
syringe barrel, and a
composition comprising TCA, optionally provided in an ampule, and optionally
including one or
more buffers or excipients, received within the reservoir.
[0082] Clause 34: The kit of clause 33, wherein the barrel is configured such
that no rubber
material and/or no corrosion-susceptible plastic material contacts the
composition held within the
reservoir.
[0083] Clause 35: The kit of clause 33 or clause 34, wherein the composition
consists essentially
of TCA.
[0084] Clause 36: The kit of clause 33 or clause 34, wherein the composition
consists of 90%
TCA.
[0085] Clause 37: The kit of any of clauses 33-36, wherein the needle is a 30-
gauge needle.
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[0086] Clause 38: The kit of any of clauses 33-37, wherein the syringe barrel
and/or are
configured to deliver aliquots of the composition when the plunger is
depressed.
[0087] Clause 39: The kit of clause 38, wherein the volume of the aliquot is
approximately
0.5 ml.
[0088] Clause 40: The kit of any of clauses 33-39, wherein the syringe barrel
or ampule is
formed of glass or a corrosion-resistant plastic.
[0089] Clause 41: The kit of any of clauses 33-40, wherein the syringe is
angled.
[0090] Clause 42: The kit of any of clauses 33-41, wherein the needle is
angled.
[0091] Clause 43: The kit of any of clauses 33-42, wherein the needle is about
10 mm to about
15 mm in length.
[0092] Clause 44: The kit of any of clauses 33-43, wherein the kit further
comprises sodium
hypochlorite, optionally in an ampule, and, optionally, EDTA and an alcohol,
optionally
isopropanol, ethyl alcohol, and/or absolute alcohol, optionally wherein the
EDTA and/or the
alcohol are provided in ampules configured to be used with the syringe.
[0093] Clause 45: A method of performing a dental pulpectomy comprising
applying a
composition comprising TCA, and optionally one or more buffers or excipients,
to dental pulp
within a root canal within the mouth of a patient.
[0094] Clause 46: The method of clause 45, wherein the composition consists
essentially of
TCA.
[0095] Clause 47: The method of clause 45, wherein the composition consists of
TCA.
[0096] Clause 48: The method of clause 45, wherein the composition consists of
90% aqueous
TCA.
[0097] Clause 49: The method of any of clauses 45-48, wherein the composition
is applied to
the dental pulp t for not more than five minutes, preferably not more than
four minutes, preferably
not more than three minutes, most preferably not more than two minutes.
[0098] Clause 50: The method of any of clauses 45-49, wherein the composition
is applied as
an irrigation fluid.
[0099] Clause 51: The method of any of clauses 45-49, wherein the composition
is absorbed or
impregnated in a carrier, and the carrier is applied to the dental pulp.
[00100] Clause 52: The method of clause 51, wherein the carrier is an
absorbent paper, gauze,
or other absorbent material that can hold the composition.
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[00101] Clause 53: The method of any of clauses 45-52, wherein the method
further comprises
applying sodium hypochlorite, optionally after washing or flushing the
composition comprising
TCA.
[00102] Although the invention has been described in detail for the purpose of
illustration based
on what is currently considered to be the most practical aspects, it is to be
understood that such
detail is solely for that purpose and that the invention is not limited to the
disclosed embodiments,
but, on the contrary, is intended to cover modifications and equivalent
arrangements that are within
the spirit and scope of the appended claims. For example, it is to be
understood that the present
invention contemplates that, to the extent possible, one or more features of
any embodiment can
be combined with one or more features of any other embodiment.
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