U.S. patent application number 11/805672 was filed with the patent office on 2008-04-10 for methods for making provisional and long-term dental crowns and bridges.
Invention is credited to Andrew M. Lichkus, Benjamin Jiemin Sun, Andrew Mathias Young.
Application Number | 20080085493 11/805672 |
Document ID | / |
Family ID | 38917393 |
Filed Date | 2008-04-10 |
United States Patent
Application |
20080085493 |
Kind Code |
A1 |
Sun; Benjamin Jiemin ; et
al. |
April 10, 2008 |
Methods for making provisional and long-term dental crowns and
bridges
Abstract
The invention provides methods of making provisional and
long-term dental restorations, particularly dental veneers, crowns
and bridges. In one embodiment, the restoration can be fabricated
indirectly by a dental laboratory. In another version, a dental
practitioner can make the restoration chairside for a patient in a
dental office. A polymerizable dental composite material, which is
dimensionally shape-stable in its uncured state, is used to make
the restoration. The material includes a polymerizable acrylic
compound, polymerization initiator system capable of being
activated by light or heat, and a filler material. The resulting
dental restoration has good aesthetics, mechanical strength, and
margins and contacts.
Inventors: |
Sun; Benjamin Jiemin; (York,
PA) ; Young; Andrew Mathias; (Dallastown, PA)
; Lichkus; Andrew M.; (York, PA) |
Correspondence
Address: |
DENTSPLY INTERNATIONAL INC
570 WEST COLLEGE AVENUE
YORK
PA
17404
US
|
Family ID: |
38917393 |
Appl. No.: |
11/805672 |
Filed: |
May 24, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60848117 |
Sep 29, 2006 |
|
|
|
Current U.S.
Class: |
433/223 ;
29/896.1; 425/2 |
Current CPC
Class: |
A61C 5/77 20170201; A61C
19/003 20130101; A61C 13/0003 20130101; Y10T 29/49567 20150115;
A61C 13/20 20130101 |
Class at
Publication: |
433/223 ;
029/896.1; 425/002 |
International
Class: |
A61C 5/10 20060101
A61C005/10 |
Claims
1. A method of forming a dental restoration, comprising the steps
of: dispensing a heated polymerizable composite material into a
matrix; positioning the matrix over an area of a pre-formed dental
model that will receive the restoration and allowing the composite
material to set on the model; allowing the composite material to
cool and form a dimensionally shape-stable, uncured restoration on
the model; removing the matrix from the model; irradiating the
composite material with light so that it cures and forms a hardened
restoration on the model; and removing the restoration from the
model.
2. The method of claim 1, wherein the composite material comprises:
polymerizable acrylic compound; polymerization initiation system
capable of being activated by light or heat, for polymerizing the
composition; and filler material.
3. The method of claim 2, wherein the polymerizable acrylic
compound of the composition is a semi-crystalline material.
4. The method of claim 2, wherein the polymerization initiation
system of the composition comprises a photoactive agent.
5. The method of claim 4, wherein the polymerization initiation
system of the composition comprises camphorquinone.
6. The method of claim 4, wherein the polymerization initiation
system of the composition comprises
2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide.
7. The method of claim 2, wherein the composition further comprises
a filler material selected from the group of inorganic and organic
materials and mixtures thereof.
8. A method of forming a dental restoration, comprising the steps
of: dispensing a heated polymerizable composite material into a
hardened dental impression of a patient; positioning the impression
containing the composite material in the mouth of a patient so that
the composite material is molded over a targeted area that will
receive the restoration; allowing the material to cool and form a
dimensionally shape-stable, uncured restoration; removing the
impression containing the composite material from the mouth;
irradiating the restoration with light so that it cures and forms a
hardened restoration.
9. The method of claim 8, wherein the restoration is maintained
within the impression material prior to being irradiated with
light.
10. The method of claim 8, wherein the restoration is removed from
the impression material prior to being irradiated with the
light.
11. The method of claim 10, wherein the restoration is placed back
inside of the mouth after it has been removed from the impression
material and prior to irradiation with light so that the patient
can bite down upon the restoration and the fit of the restoration
can be checked.
12. A method of forming a dental restoration, comprising the steps
of: dispensing a heated polymerizable composite material into a
hardened dental impression of a patient; placing the impression
containing the composite material in the mouth of a patient so that
the composite material is molded over a targeted area that will
receive the restoration; allowing the material to cool and form a
dimensionally shape-stable, uncured restoration; removing the
impression from the mouth while leaving the shape-stable, uncured
restoration over the targeted area inside of the mouth so that the
restoration can be fitted; removing the restoration from the mouth
and irradiating it with light so that it cures and forms a hardened
restoration.
13. The method of claim 12, wherein the patient bites down upon the
restoration prior to removing the restoration from the mouth so
that the fit of the restoration can be checked.
14. The method of claim 8 or 12, wherein the uncured restoration is
irradiated with light while it is positioned inside of the mouth so
that it partially cures.
15. The method of claim 8 or 12, wherein the composite material
comprises: polymerizable acrylic compound; polymerization
initiation system capable of being activated by light or heat, for
polymerizing the composition; and filler material.
16. The method of claim 15, wherein the polymerizable acrylic
compound of the composition is a semi-crystalline material.
17. The method of claim 15, wherein the polymerization initiation
system of the composition comprises a photoactive agent.
18. The method of claim 17, wherein the polymerization initiation
system of the composition comprises camphorquinone.
19. The method of claim 17, wherein the polymerization initiation
system of the composition comprises
2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide.
20. The method of claim 15, wherein the composition further
comprises a filler material selected from the group of inorganic
and organic materials and mixtures thereof.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Patent Application 60/848,117 having a filing date of Sep. 29,
2006, the entire contents of which are hereby incorporated by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to methods for
making provisional and long-term dental crowns, bridges, inlays,
onlays, veneers, and other dental restorations. A polymerizable
composite resin having good dimensional shape-stability is used to
make the dental restoration. In one method, the restoration can be
fabricated indirectly by a dental laboratory and sent to a dentist
for placing in the mouth of a patient. In another version, the
dentist can make the restoration in the dental office directly. The
restoration can be made at the side of the dental chair where the
patient is seated.
[0004] 2. Brief Description of the Related Art
[0005] Dental restorations, such as crowns and bridges, are used to
restore or replace lost tooth structure, teeth, or oral tissue.
Provisional (or temporary) restorations are intended to be used for
a relatively short time. For example, a dentist will often use a
provisional crown, until a permanent crown is ready to be placed in
the mouth of a patient. Following one conventional procedure, the
dentist makes the provisional crown for the patient at the dental
office and a dental laboratory makes the permanent crown. The
dentist mounts the provisional crown to protect the tooth while the
permanent crown is being made. Later, the dentist removes the
provisional crown and replaces it with the permanent crown.
[0006] The provisional crown typically is made from a polymeric
material such as an acrylic. In one method used to prepare a
provisional crown, a polymerizable material is placed in a
pre-formed impression which then is inserted into the patient's
mouth. The polymerizable material is molded over the prepared tooth
structure by pressing the impression thereon. Then, the impression
containing the molded material, which may only be partially-cured
at this point, is removed from the patient's mouth. The material is
fully cured by a self (chemical)-curing, light-curing, or
heat-curing mechanism, which may occur outside of the mouth, to
form the ultimate provisional crown. Finally, the dental
practitioner places the provisional crown over the prepared tooth
and bonds the crown to the tooth using temporary dental cement. The
provisional crown helps maintain the health and function of the
tooth while the dental laboratory manufactures the permanent crown.
At a subsequent office visit, the dentist removes the provisional
crown and checks the color, occlusion, and fit of the permanent
crown. If satisfactory, the dentist affixes the permanent crown to
the tooth using permanent dental cement.
[0007] Dental compositions containing polymerizable resins and
filler particles often are used to prepare provisional crowns,
bridges, and other restorations. Such dental compositions can be
self (chemically)-curable, light-curable, or dual-curable. The
dental compositions are cured and hardened by different chemical
mechanisms to form a strong and durable material. In one example, a
dentist uses a self-curing composition, which is prepared from two
paste components. One component used to make the composition is a
base paste and the other component is a catalyst paste. The base
paste typically contains polymerizable monomers such as
methacrylate or acrylate monomers; a free-radical polymerization
accelerator such as a tertiary amine; and fillers such as silica,
glasses, or alumina. Meanwhile, the catalyst paste typically
includes a polymerizable monomer, a free-radical polymerization
initiator such as dibenzoyl peroxide, and fillers.
[0008] To prepare the composition, the amine-containing base and
peroxide-containing catalyst pastes are combined and mixed
together. Typically, the respective pastes are stored separately in
side-by-side auto-mix cartridges. When a dentist is ready to
prepare the composition, the pastes are extruded through a
dispensing tip attached to the cartridges. The dispensing tip
normally contains a static mixing element. As the pastes are mixed
together, the catalyst system (amine and peroxide) react with each
other and initiate polymerization and hardening of the composition.
The polymerization process involves a reaction between the reducing
agent (amine) and oxidizing agent (peroxide). This mechanism is
commonly referred to as a redox mechanism.
[0009] Compositions that can be used to make temporary crown and
bridges are described generally in the patent literature. For
example, May et al., U.S. Pat. No. 5,376,691 discloses dental
cement for making temporary crowns and bridges. The dental cement
is prepared from a first paste comprising a difunctional acrylate
such as urethane diacrylate, an activator such as a tertiary amine,
and radiopaque filler such as barium and/or strontium glasses. The
second paste includes no substance having active double bonds, a
catalyst such as dibenzoyl peroxide, a silicon dioxide material,
and a softener that cannot be polymerized along with the other
components but is sufficiently insoluble in the mouth. The
softeners can be selected from such compounds as liquid paraffins,
long-chain glycols, and inert alkylphthalates.
[0010] Tateosian et al., U.S. Pat. No. 5,554,665 discloses a dental
composition that is formed by the static mixing of two
complementary pastes. A catalyst paste includes a polymerizable
methacrylate, a peroxide, and a stabilizer such as butylated
hydroxytoluene. The stabilizer is effective at preventing
polymerization for at least 180 days at 23.degree. C. A
complementary accelerator and radiation-cure initiator paste
includes a polymerizable methacrylate and a reducing agent for the
peroxide such as dihydroxyethyl-p-toluidine. According to the '665
patent, the paste compositions preferably have substantially the
same viscosity and are mixed in a volume ratio between 1:1 and
1:5.
[0011] Xie, U.S. Pat. No. 5,977,199 discloses a delivery system for
delivering dental cement material for making temporary crowns and
bridges. A catalyst paste and base paste are dispensed from a dual
cartridge and mixed in a static mixer to form a polymerizing
material. The catalyst paste comprises at least one polymerizable
monomer, polymerization initiator, polymerization inhibitor, and
filler. The base paste comprises at least one polymerizable
monomer, at least one polymerization accelerator, polymerization
inhibitor, and filler. According to the '199 patent, the viscosity
of the catalyst paste must be substantially greater than the
viscosity of the base paste in order for the mixture to cure
effectively.
[0012] Conventional temporary dental restorations, such as
provisional crowns and bridges, are used by patients for a
relatively short period of time. As discussed above, the
provisional crown is used by the patient while a permanent crown is
made. Today, provisional crowns and bridges typically are used by a
patient for a period of about three to six months. In general, such
provisional restorations are effective, but there is a need in the
dental field for restorations that can be used for longer
periods.
[0013] The present invention provides methods for making such
dental restorations. A dental practitioner can use the resulting
dental restoration as a provisional expecting that it will remain
in the patient's mouth for a time period of about 1 to about 12
months. On the other hand, if the dental practitioner wishes to use
the dental restoration as a long-term product, expecting that it
will remain in the patient's mouth for a period of time longer than
about 12 months, he or she can do so. The dental restorations of
this invention can be used as either provisional or long-term
dental products because of their advantageous properties.
Particularly, the restorations are strong and durable and do not
break or fracture easily. Because of their mechanical strength, the
restorations can withstand hard occlusion forces. In addition, the
restorations have pleasing aesthetics matching the shade of natural
teeth. Moreover, the restorations have good margins and contacts,
providing the patient with comfort while promoting dental health.
The restoration covers and supports the tooth structure
sufficiently so that it protects the tooth's pulpal portion.
[0014] One object of the present invention is to provide a method
that a dental laboratory can use to make dental crowns, bridges,
inlays, onlays, veneers, and other dental restorations having good
mechanical strength, aesthetics, and occlusal fit.
[0015] Another object of this invention is to provide a method that
a dental practitioner can use to design and fabricate the crown,
bridge, or other dental restoration "chairside." This would help
make the crown manufacturing and fitting process less
time-consuming and costly. The dentist may be able to mount the
crown on the patient's tooth in a single office visit.
[0016] These and other objects, features, and advantages of this
invention are evident from the following description and
illustrated embodiments.
SUMMARY OF THE INVENTION
[0017] This invention provides methods for making provisional and
long-term dental crowns, bridges, inlays, onlays, veneers, and
other dental restorations. In one version, a dental laboratory can
make the restoration. This method involves dispensing a heated
polymerizable composite material into a matrix and positioning the
matrix over an area of a pre-formed dental model that will receive
the restoration. The composite material may comprise polymerizable
acrylic compound, polymerization system capable of being activated
by light or heat for polymerizing the composition, and filler
material.
[0018] The composite material is allowed to set and cool and form a
dimensionally shape-stable uncured restoration on the dental model.
The matrix is then removed, while the composite material, in the
shape of the restoration, remains seated on the model. Light is
used to irradiate the composite material so that it cures and forms
a hardened restoration directly on the model. Finally, the
restoration is removed, finished, and polished. A visible
light-curing sealant can be applied to provide a stain-resistant
and glossy surface finish to the restoration if desired. The
restoration is now ready to be mounted on a patient's tooth.
[0019] In another embodiment, a dental practitioner can make the
dental restoration at the patient's chair in the dental office.
This method involves dispensing a heated polymerizable composite
material into a hardened dental impression. The same composite
material as described above can be used in this method. The
practitioner positions the impression containing the composite
material in the mouth of a patient so that the material is molded
over the targeted area that will receive the restoration. The
material is allowed to cool and form a dimensionally shape-stable,
uncured restoration. The impression containing the composite
material is removed from the mouth. Then, the restoration is
irradiated with light so that it cures and hardens. The restoration
can be maintained within the impression material while it is being
light-cured. Alternatively, the restoration can be removed from the
impression material before it is light-cured.
[0020] Another chairside method involves removing the impression
from the mouth, while leaving the shape-stable, uncured restoration
over the targeted area inside of the mouth so that the restoration
can be fitted. Then, the restoration is removed from the mouth and
irradiated with light so that it cures and hardens. If desired, the
uncured restoration can be irradiated with light while it is
positioned in the mouth so that it partially cures.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] The present invention relates to methods of making dental
crowns, bridges, inlays, onlays, veneers, and other dental
restorations using polymerizable dental composite material having
good dimensional stability. In one embodiment, the restoration can
be fabricated indirectly by a dental laboratory and sent to a
dentist for placing in the mouth of a patient. In another version,
the dentist can make the restoration at the chair of the dental
patient in the dental office.
[0022] The polymerizable dental composite material used in
accordance with this invention comprises a polymerizable acrylic
compound; a polymerization initiation system, capable of being
activated by light or heat for polymerizing the composition; and a
filler material. The material can be prepared using the following
components.
Dental Composite Material
Polymerizable Acrylic Compounds
[0023] Polymerizable acrylic compounds that can be used in the
composition of this invention, include, but are not limited to,
mono-, di- or poly-acrylates and methacrylates such as methyl
acrylate, methyl methacrylate, ethyl acrylate, isopropyl
methacrylate, n-hexyl acrylate, stearyl acrylate, allyl acrylate,
glycerol diacrylate, glycerol triacrylate, ethyleneglycol
diacrylate, diethyleneglycol diacrylate, triethyleneglycol
dimethacrylate, tetraethylene glycol di(meth)acrylate,
1,3-propanediol diacrylate, 1,3-propanediol dimethacrylate,
trimethylolpropane tri(meth)acrylate, 1,2,4-butanetriol
trimethacrylate, 1,4-cyclohexanediol diacrylate,
1,4-cyclohexanediol dimethacrylate, 1,6-hexanediol
di(meth)acrylate, pentaerythritol triacrylate, pentaerythritol
tetraacrylate, pentaerythritol tetramethacrylate, sorbitol
hexacrylate,
2,2-bis[4-(2-hydroxy-3-acryloyloxypropoxy)phenyl]propane;
2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane
(Bis-GMA); 2,2-bis[4-(acryloyloxy-ethoxy)phenyl]propane;
2,2-bis[4-(methacryloyloxy-ethoxy)phenyl]propane (or ethoxylated
bisphenol A-dimethacrylate) (EBPADMA); urethane di(meth)acrylate
(UDMA), diurethane dimethacrylate (DUDMA), polyurethane
dimethacrylate (PUDMA); 4,13-dioxo-3,14
dioxa-5,12-diazahexadecane-1,16-diol diacrylate; 4,13-dioxo-3,14
dioxa-5,12-diazahexadecane-1,16-diol dimethacrylate; the reaction
product of trimethyl 1,6-diisocyanatohexane and bisphenol A
propoxylate and 2-hydroxyethyl methacrylate (TBDMA); the reaction
product of 1,6 diisocyanatohexane and 2-hydroxyethyl methacrylate
modified with water (HDIDMA); the reaction product of 1,6
diisocyanatohexane and 2-hydroxyethyl acrylate modified with water
(HDIDA); alkoxylated pentacrythritol tetraacrylate; polycarbonate
dimethacrylate (PCDMA); the bis-acrylates and bis-methacrylates of
polyethylene glycols; and copolymerizable mixtures of acrylated
monomers and acrylated oligomers.
[0024] In addition to the foregoing polymerizable acrylic
compounds, the composition may contain acidic monomers such as
dipentaerythritol pentacrylate phosphoric acid ester (PENTA);
bis[2-(methacryloxyloxy)-ethyl]phosphate; and vinyl compounds such
as styrene, diallyl phthalate, divinyl succinate, divinyl adipate
and divinylphthalate. Diluent polymerizable monomers also may be
added to the composition. For example, hydroxy alkyl methacrylates,
ethylene glycol methacrylates, and diol methacrylates such as
tri(ethylene glycol) dimethacrylate (TEGDMA) may be added to reduce
viscosity and make the composition more suitable for application. A
polymerizable acrylic compound can be used alone in the composition
or mixtures of the compounds can be used.
Polymerization System
[0025] A polymerization system can be used in the composition of
this invention, which initiates polymerization (hardening) of the
composition by a light-curable or heat-curable reaction. In one
embodiment, a photoactive agent such as, for example, benzophenone,
benzoin and their derivatives, or alpha-diketones and their
derivatives is added to the composition in order to make it
light-curable. A preferred photopolymerization initiator is
camphorquinone (CQ). Photopolymerization can be initiated by
irradiating the composition with blue, visible light preferably
having a wavelength in the range of about 380 to about 500 nm. A
standard dental blue light-curing unit can be used to irradiate the
composition. The camphorquinone (CQ) compounds have a light
absorbency maximum of between about 400 to about 500 nm and
generate free radicals for polymerization when irradiated with
light having a wavelength in this range. Photoinitiators selected
from the class of acylphosphine oxides can also be used. These
compounds include, for example, monoacyl phosphine oxide
derivatives, bisacyl phosphine oxide derivatives, and triacyl
phosphine oxide derivatives. For example,
2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (TPO) can be used
as the photopolymerization initiator. In one embodiment, a material
referred to as "ALF" comprising camphorquinone (CQ); butylated
hydroxytoluene (BHT); N,N-dimethylaminoneopentyl acrylate, and
methacrylic acid can be used in the composition.
[0026] In another embodiment, heat-activated polymerization
initiators, such as peroxides, can be added to make the composition
heat-curable. The peroxides generate free radicals to initiate
polymerization and hardening of the composition at elevated
temperature. Peroxides such as dibenzoyl peroxide (BPO),
di-p-chlorobenzoyl peroxide, di-2,4-dichlorobenzoyl peroxide,
tertiary butyl peroxybenzoate, methyl ethyl ketone peroxide,
ditertiary butyl peroxide, dicumyl peroxide and cumene
hydroperoxide, and the like can be used.
[0027] In addition to the photoactive and heat activated agents,
the composition may include a polymerization inhibitor such as, for
example, butylated hydroxytoluene (BHT); hydroquinone; hydroquinone
monomethyl ether; benzoquinone; chloranil; phenol; butyl
hydroxyanaline (BHT); tertiary butyl hydroquinone (TBHQ);
tocopherol (Vitamin E); and the like. Preferably, butylated
hydroxytoluene (BHT) is used as the polymerization inhibitor. The
polymerization inhibitors act as scavengers to trap free radicals
in the composition and to extend the composition's shelf life.
Fillers
[0028] Conventional filler materials, including reactive and
non-reactive fillers, may be added to the composition. Reactive
fillers include metal oxides and hydroxides, metal salts, and
glasses that are acid-reactive. Such fillers are commonly used in
dental ionomer cements. Examples of metal oxides include, but are
not limited to, barium oxide, calcium oxide, magnesium oxide, and
zinc oxide can be used. Examples of metal salts include, but are
not limited to, aluminum acetate, aluminum chloride, calcium
chloride, magnesium chloride, zinc chloride, aluminum nitrate,
barium nitrate, calcium nitrate, magnesium nitrate, and strontium
nitrate. Suitable glasses include, but are not limited to, borate
glasses, phosphate glasses, and fluoroaluminate glasses. The
glasses may or may not have fluoride-releasing properties. The
benefits of using fluoride-releasing glasses are well known. Such
materials are capable of releasing fluoride into the oral cavity
over the long term. Fluoride generally provides added protection
against acid attack that can cause tooth decay. Although, such
fluoride-releasing glasses are generally not used in temporary
dental restorations, since such restorations are intended for
short-term use only. Organic particles such as poly(methyl
methacrylate), poly(methyl/ethyl methacrylate), crosslinked
polyacrylates, polyurethanes, polyethylene, polypropylene,
polycarbonates and polyepoxides, and the like also can be used as
fillers.
[0029] A wide variety of non-acid reactive filler materials also
can be added to the composition. Inorganic fillers, which can be
naturally-occurring or synthetic, can be added. Such materials
include, but are not limited to, silica, titanium dioxide, iron
oxides, silicon nitrides, glasses such as calcium, lead, lithium,
cerium, tin, zirconium, strontium, barium, and aluminum-based
glasses, borosilicate glasses, strontium borosilicate, barium
silicate, lithium silicate, lithium alumina silicate, kaolin,
quartz, and talc. Preferably, the silica is in the form of
silanized fumed silica. A preferred glass filler is silanized
barium boron aluminosilicate.
[0030] The average particle size of the particles comprising the
filler material is normally in the range of about 0.1 to about 10
microns and more preferably in the range of about 0.1 to about 5
microns. If a fumed silica filler material is used, the silica
particles are preferably nanometer-sized. The silica particles
preferably have an average diameter of less than 200 nm. The filler
particles can be surface-treated with a silane compound or other
coupling agent to improve bonding between the particles and resin
matrix. Suitable silane compounds include, but are not limited to,
gamma-methacryloxypropyltrimethoxysilane,
gamma-mercaptopropyltriethoxysilane,
gamma-aminopropyltrimethoxysilane, and combinations thereof.
[0031] In one preferred embodiment, the composition comprises about
5 to about 15 wt. % TBDMA; about 3 to about 10 wt. % HDIDMA; about
1.5 to about 5 wt. % HDIDA; about 5 to about 10 wt. % UDMA; about 5
to about 10 wt. % EBPADMA; about 0 to about 0.5 wt. % TPO; about
0.1 to about 1.0 wt. % ALF and about 50 to about 80 wt. % filler
material (silicon dioxide/glass). In another embodiment, the
composition is substantially free of the ALF activator.
[0032] TBDMA is added to the composition in the form of semi-solid
high molecular weight oligomers. The addition of TBDMA provides the
composite with good toughness and strength, good handling
properties and adjusts the reflective index of the composite
material to provide the desired translucency. HDIDMA and HDIDA are
added as solid, semi-crystalline monomers. The H.sub.2O modified
HDIDMA and HDIDA also provides a reduced crystallization time. UDMA
and EBPADMA are added as liquids in order to impart flowability to
the composite material at elevated temperatures, while assisting in
decreasing the cure time, Lucrin-TPO and ALF are photoinitiators
that initiate the polymerization of the monomers and oligomers and
provide a relatively short cure time. Pigments are used to adjust
the shade of the composite. The filler materials added to the
composition to provide the composition with beneficial mechanical
properties.
[0033] As described further below, the composite material used in
the method of this invention is dimensionally stable when it is in
its uncured state. The composite material, with its
semi-crystalline components as described above, forms a hard,
non-sticky surface layer upon being crystallized. The
semi-crystalline components are partially recrystallizable and help
the material to rapidly solidify. When polymerized, the
crystallized phase melts effectively resulting in volume expansion,
which offsets polymerization shrinkage somewhat. The resulting
material has low shrinkage and stress.
[0034] The above-described composition can be used to fabricate
dental crowns, bridges, inlays, onlays, veneers, and other dental
restorations. Although the method of this invention is described
primarily below as a method for making a dental crown, it should be
understood that the method can be used to make any desired dental
restoration.
Methods
Indirect Dental Laboratory Method
[0035] In one method for making the dental crown, which can be
referred to as an indirect dental laboratory method, the dentist
first takes an initial impression of the patient's entire dental
anatomy including the tooth that will receive the crown using
conventional techniques.
[0036] The impression material is normally prepared from two paste
components. At least one of the paste components contain an
elastomeric material such as vinyl terminated polysiloxanes capable
of undergoing addition polymerization. Once the pastes are mixed
together, they start to harden and form a rubbery material. The
dentist dispenses the impression material into a bite tray and
inserts the tray into a patient's mouth. The patient bites down on
the impression material in the tray. Then, the tray is removed from
the mouth and the impression material is allowed to cure and
harden. A negative impression of the teeth, including the
unprepared tooth that will receive the crown, and surrounding gum
tissue is formed.
[0037] In some cases, the dentist will prepare the tooth that will
receive the crown during this office visit. The dentist performs
"crown prep" work on the tooth by filing and grinding it to a
"core" or "stump." A high-speed or low-speed handpiece equipped
with a diamond bur is used to grind the tooth. The dentist then
takes an impression of the prepared tooth following the same
techniques as described above. Following this procedure means that
two hardened impressions are formed, a first impression of the
patient's full dental anatomy containing the unprepared tooth and a
second impression containing the crown-prepped tooth that will
eventually receive the crown. At this point, a conventional
provisional crown can be mounted over the prepared tooth structure
to protect it while the permanent crown is being made.
[0038] The hardened impressions are sent to a dental laboratory
that will fabricate the crown. The dental technician, at the
laboratory, prepares a cast (or model) by pouring dental plaster or
stone into the first hardened impression. This results in a
finished plaster model having a shaped surface closely matching the
patient's complete dental anatomy. In other cases, the dentist will
prepare the finished plaster models and send them directly to the
laboratory.
[0039] Next, the laboratory technician prepares a matrix using a
matrix putty made from silicone or other moldable material. The
matrix putty has good handling properties. The technician can mold
and shape the matrix over the area of the model requiring the
crown.
[0040] To make the matrix, the technician may need to fill in
edentulous areas on the dental model with a denture tooth, shape
and contour the tooth anatomy using wax or resin, and make other
modifications to the model. The model teeth should be clean and
free of any foreign debris. Then the matrix putty is molded over
the shaped teeth. The matrix should be molded over the teeth so
that it extends beyond the margins of the teeth. Particularly, it
should extend at least 2 mm beyond the tooth margins.
[0041] The technician presses the matrix putty on the surface of
the teeth to form the impression. The matrix putty is allowed to
harden. Then, the hardened matrix is removed from the model. The
resulting impression in the hardened matrix is an accurate negative
likeness of the patient's tooth anatomy. Now, the crown is ready to
be fabricated using the composite material of this invention.
[0042] It can be difficult to apply the composite material to the
dental model if there are jagged edges or irregular formations
present on the model. Thus, the dental model should first be
prepared eliminate any unnecessary protrusions. The crown portion
of the teeth of the model can be reduced using a bur or other sharp
instrument. Typically, the crown portion is reduced by a depth of
approximately 1.0 mm. Also, adjacent teeth on the model may be
inadvertently fused together, and the interproximal contacts of the
fused teeth should be removed using a saw instrument. Once the
model has been adequately reduced and prepared, a thin coating of a
separating agent (for example, oxygen barrier coating available
from Dentsply) is applied to the surface of the model.
[0043] As discussed above, if the dentist has prepared the tooth
for receiving the crown in the office visit and taken an impression
of the prepared tooth, a second dental model of the patient's
dental anatomy including the crown-prepped tooth is fabricated. The
dental laboratory may make this model, or the dentist may make this
model at his/her office and send it to the laboratory. In such
cases, the oxygen barrier coating or other separating agent is
applied to the surface of this model to prepare it.
[0044] Next, the dental practitioner or laboratory technician
dispenses layers of the dental composite material of this invention
into the hardened matrix putty. The composite material is heated to
a temperature generally above 40.degree. C. and preferably to a
temperature in the range of about 50.degree. C. to about
100.degree. C. If the temperature is too low, the material will not
flow sufficiently. On the other hand, if the temperature is too
high, the material will take a substantially long time to cool. The
practitioner places layers of the composite material into the
matrix beginning with the enamel layer. The heated enamel layer is
carefully smoothed out using a spatula, preferably a heated
spatula, or other applicator. Then, the practitioner applies more
composite material to the matrix to form the dentin layer. Care
should be taken that the correct amount of composite material is
placed into the matrix. If a sufficient amount of composite
material is not introduced, gaps will form in the resulting crown,
and there will be occlusion problems. On the other hand, if too
much composite material is introduced, the occlusion of the crown
may be too high. This can occur even though the highly flowable
nature of the heated composite material allows excess material to
squeeze out easily. The shade of the composite material is
carefully selected so that it matches the color of the patient's
natural teeth.
[0045] Once the hardened matrix has been filled sufficiently with
the composite material, it is placed over the area of the dental
model that includes the tooth to receive the crown. If only one
model of the teeth containing the unprepared tooth has been made,
as described above, then the composite material is applied to this
model. In cases where two dental models have been made, a first
model containing the unprepared tooth and a second model containing
the crown-prepped tooth, then the composite material is applied to
the second model.
[0046] Once seated, the composite material is allowed to set for
approximately one to three minutes to form a shape-stable, uncured
provisional crown. The hardened matrix is then removed from the
model leaving the composite material in the shape of a dental crown
seated on the model. Although the composite material is uncured at
this point, it is dimensionally stable, and it remains
substantially fixed in place. The composite material has wax-like
characteristics, good viscosity, and handling properties. The
material does not slump or substantially change shape. Contoured
and molded to form a crown on the targeted area of the dental
model, the composite material does not expand or shrink
substantially from that site. By contrast, conventional materials
may have poor viscosity and handling characteristics. Such
materials may be too thin so that they lose their shape or too
thick so that they are difficult to mold.
[0047] If necessary, additional composite material can be added to
touch-up the provisional crown as it is seated on the model. Any
excess composite material on the model should be removed. A knife
or other sharp instrument can be used to scrape off the excess
material. Then, a thin layer of a visible light curing (VLC) sealer
is applied to the surface of the provisional crown. Now, the model,
which is seated with the composite material in a crown shape, is
placed in a light-curing oven and irradiated with curing light and
heated in accordance with a pre-determined curing cycle. The curing
time will depend upon many different factors including the
light-curing oven used. In general, the materials of this invention
completely set and harden in the range of about one (1) to about
fifteen (15) minutes.
[0048] After the cured dental crown and supporting model are
removed from the oven, the assembly is cooled. Then, the crown is
removed from the model using fingers, a crown remover, or other
suitable instrument. The crown is finished and polished using
conventional techniques. The crown can be polished using buffing
wheels. Aluminum oxide can be used to steam clean the provisional
crown. If needed, the provisional crown also can be mechanically
polished using buffing wheels and abrasives. Lastly, if the
practitioner or technician wishes, a VLC sealant which provides a
stain-resistant and glossy surface finish may be applied to the
surface of the crown and the crown may be cured again in a
light-curing oven.
[0049] The dental laboratory sends the finished crown back to the
dentist. Once the dentist receives the crown, he or she can prepare
the tooth that will receive the crown, if this has not already been
done, by filing the tooth structure to a core or stump as described
above. Then, the finished crown is affixed to the prepared tooth in
the mouth of the patient using a suitable reline material and
dental cement. Conventional dental cements, as are known in the
dental field, may be used in this step. In cases where a temporary
crown has been mounted over the tooth structure, it is first
removed and then the crown of this invention is affixed to the
tooth using a dental cement.
Dental Practitioner's Chairside Method
[0050] Following this method, a dental practitioner first takes an
impression of the patient's teeth including the unprepared tooth
that will receive the crown. The dentist takes this impression
using the same techniques as described above. A plastic tray that
is filled with polyvinyl siloxane (PVS), alginate, or other
suitable impression material is used. The dentist presses the tray
containing the silicone material on the surface of the teeth to
form the impression. After the impression has been formed in the
silicone material, the dentist removes the tray from the mouth. The
impression is allowed to harden. The resulting hardened impression
is an accurate negative likeness of the patient's tooth
anatomy.
[0051] Then, the dentist places multiple layers of the
above-described composite material into the hardened impression
beginning with the enamel layer. The composite material is heated
and carefully placed into desired incisal areas of the impression
to form the enamel layer. Next, the dentin layer is injected into
the impression. As discussed above, it is important that the
correct amount of composite material be placed into the impression.
The shade of the composite material is also carefully selected and
customized so that it matches the color of the patient's natural
teeth. Alternatively, the dentist may wish to inject only a single
layer of the shaded composite material into the hardened
impression.
[0052] After filling the impression with the composite material, it
is inserted into the patient's mouth. It is positioned in the mouth
in such a way that the composite material is molded and shaped over
the previously prepared tooth that will receive the restoration. As
the impression is fitted in the mouth, excess composite material is
allowed to escape around the margins and adjacent teeth.
[0053] Alternatively, the dentist can prepare a model and work
outside of the mouth. In this case, the dentist takes an impression
of the prepared tooth using conventional impression material. A
model including a core or stump tooth structure is then made by
pouring or injecting a low viscosity and suitably rigid die
material, such as die silicone, plaster, dental stone, or the like
into the hardened impression. Then, the impression which contains
the composite material as described above can be fitted over the
dental model and a crown can be prepared. Following this method,
the dentist can work extraorally to prepare the crown.
[0054] Turning back to the chairside method described above, the
composite material is allowed to cool and form a dimensionally
stable, uncured crown structure within the impression inside of the
mouth. The impression containing the composite material is then
removed from the mouth. If needed, the dentist trims excess
composite material away from the margins and adjacent teeth. Next,
the uncured, shaped crown structure is placed back inside of the
mouth so that the crown is positioned over the prepared tooth
structure. The patient can bite down on the crown so that margins,
contacts, and occlusion can be checked by the practitioner and
adjusted accordingly. The fitted crown is then removed from the
mouth.
[0055] Next, the crown is irradiated with light so that it cures
and forms a fully hardened crown product. A standard handheld
dental curing light or light-curing oven may be used to fully cure
the crown structure. Suitable light-curing ovens are available from
Dentsply including, for example, the Eclipse.RTM. processing unit,
Enterra.RTM. visible light-curing (VLC) unit, and Triad.RTM. 2000
VLC unit. Suitable handheld light units include halogen, plasma arc
(PAC), and light-emitting diode (LED) dental curing lights. These
include, for example, those sold under the brand names: QHL75.RTM.
Lite (Dentsply); Spectrum.RTM. 800 curing unit (Dentsply); Sapphire
(DenMat); SmartLite iQ2.TM. (Dentsply); Elipar.RTM. (3M Espe); and
L.E. Demetron II.TM. (Kerr).
[0056] The crown can be finished with burs and polished using
customary finishing techniques as needed. In addition, a VLC
sealant, which provides a stain-resistant and glossy surface finish
may be applied to the crown.
[0057] The finished crown is now ready to be permanently affixed to
the tooth. Conventional permanent cements, as known in the dental
field, may be used in this step.
[0058] In a second embodiment of this method, the composite
material cools and forms a stable, uncured crown structure inside
of the mouth. But, in the next step, only the impression is removed
from the mouth. The shape-stable uncured crown structure remains in
the mouth. The dentist can then trim excess composite material away
from the margins of the crown and adjacent teeth. As the patient
bites down on the crown, the margins, contacts, and occlusion can
be checked by the practitioner and adjusted accordingly. Next, the
shaped crown structure is partially cured in the mouth using a
handheld dental curing light as described above. The partially
cured crown is then removed from the mouth. It may be finished with
a bur as needed. In addition, a sealant, which provides a
stain-resistant and glossy surface finish, may be applied to the
crown. A dental curing light or light-curing oven may be used to
fully cure the crown structure.
[0059] A third version of this method is similar to the method
described above, except there is no partial curing step. The
composite material is completely cured outside of the mouth.
Particularly, this method involves first cooling the composite
material to form a stable, uncured crown structure within the
mouth. In the next step, only the impression material is removed
from the mouth. This leaves the uncured crown structure in place.
The practitioner can check the crown fit and make any needed
adjustments. Then, the shaped crown structure is removed and fully
cured by exposing it to light radiation outside of the mouth using
dental curing lights or ovens.
[0060] Following a fourth method also allows the dentist a chance
to work outside of the mouth. First, the impression containing the
composite material is placed over a dental model. The impression is
then removed from the model, but the composite material remains.
This leaves an uncured, shape stable crown structure positioned on
the model. The crown structure can be partially light-cured on the
model if the dentist wishes to perform this step. Then, the
partially-cured crown can be removed and finished with burs and
polished to its final desired shape. After applying a sealant to
the crown's surface, it is ready to be fully cured and
hardened.
[0061] In yet another embodiment, the uncured, shaped crown
structure is removed from the impression material and only the
crown, by itself, is placed back inside of the mouth. The crown is
mounted over the prepared tooth structure and margins, contacts,
and occlusion are checked. The crown is then removed from the
mouth. As described above, the crown can be finished and a sealant
can be applied to its surface before the crown is placed in a
light-curing oven and fully cured.
[0062] One advantage of composite material of this invention is
that it can be shaped and molded to form stable crown structures
that can be partially light-cured inside of the mouth. This
partial-curing step normally occurs after the margins, contacts,
and occlusion have been checked and adjusted accordingly. The
above-mentioned dental curing lights may be used to partially cure
the material. Then, the partially-cured crown is removed from the
mouth and finished with burs and polishers to its final desired
shape. After applying a sealant to the crown's surface, it is ready
to be fully cured and hardened. The crown may be placed in a
standard light-curing oven, as mentioned above, and fully cured via
light irradiation.
[0063] The dental restorations produced by each of the methods of
this invention have excellent properties and can be used as
provisional or long-term restorations. A dental practitioner can
use the dental restoration as a provisional expecting that it will
remain in the patient's mouth for a time period of about 1 to about
12 months. Moreover, if there is a need, the dental practitioner
can use the restoration long-term, expecting that it will remain in
the patient's mouth for a period of time longer than about 12
months. The properties and other features of the restorations are
such that they can be used for either short term or long term
periods. The restorations have high mechanical strength, pleasing
aesthetics, a hard and smooth surface finish, and good margins and
contacts making them ideal products for protecting the dental
health of a patient.
[0064] The present invention is further illustrated by the
following examples, but these examples should not be construed as
limiting the scope of the invention.
EXAMPLES
Example 1
Preparation of Oligomer
[0065] A reactor was charged with 1176 grams of
trimethyl-1,6-diisocyanatohexane (5.59 mol) and 1064 grams of
bisphenol A propoxylate (3.09 mol) under dry nitrogen flow and
heated to about 65.degree. C. under positive nitrogen pressure. To
this reaction mixture, 10 drops of catalyst dibutyltin dilaurate
were added. The temperature of the reaction mixture was maintained
between 65.degree. C. and 140.degree. C. for about 70 minutes and
followed by additional 10 drops of catalyst dibutyltin dilaurate. A
viscous paste-like isocyanate end-capped intermediate product was
formed and stirred for 100 minutes. To this intermediate product,
662 grams (5.09 mol) of 2-hydroxyethyl methacrylate and 7.0 grams
of BHT as an inhibitor were added over a period of 70 minutes while
the reaction temperature was maintained between 68.degree. C. and
90.degree. C. After about five hours stirring under 70.degree. C.,
the heat was turned off, and oligomer was collected from the
reactor as semi-translucent flexible solid and stored in a dry
atmosphere.
Example 2
Preparation of Monomer
[0066] A reaction flask was charged with 700 grams of
1,6-diisocyanatohexane and heated to about 70.degree. C. under a
positive nitrogen pressure. To this reactor were added 1027 grams
of 2-hydroxyethyl methacrylate, 0.75 gram of catalyst dibutyltin
dilaurate and 4.5 grams of butylated hydroxy toluene (BHT). The
addition was slow and under dry nitrogen flow over a period of two
hours. The temperature of the reaction mixture was maintained
between 70.degree. C. and 90.degree. C. for another two hours and
followed by the addition of 8.5 grams of purified water. One hour
later, the reaction product was discharged as clear liquid into
plastic containers and cooled to form a white solid and stored in a
dry atmosphere.
Example 3
Preparation of Monomer
[0067] A reaction flask was charged with 168 grams of
1,6-diisocyanatohexane and heated to about 70.degree. C. under a
positive nitrogen pressure. To this reactor were added 228 grams of
2-hydroxyethyl acrylate, 0.12 gram of catalyst dibutyltin dilaurate
and 0.86 grams of butylated hydroxy toluene (BHT). The addition was
slow and under dry nitrogen flow over a period of two hours. The
temperature of the reaction mixture was maintained between
70.degree. C. and 85.degree. C. for another three hours and
followed by the addition of 0.9 grams of purified water. One hour
later, the reaction product was discharged as clear liquid into
plastic containers and cooled to form a white solid and stored in a
dry atmosphere.
Examples 4A-4D
Preparation of Polymerizable Composite Materials
[0068] In the following Examples 4A-4D, different polymerizable
composite materials were prepared as described further below.
TABLE-US-00001 TABLE 1 Formulations of Composite Resins Example
Example Example Example Components 4A (wt %) 4B (wt %) 4C (wt %) 4D
(wt %) Oligomer of Example 1 8.072 8.033 8.072 8.033 Monomer of
Example 2 5.24 5.24 5.24 5.24 Monomer of Example 3 3.50 3.50 3.50
3.50 (HEMA-UDMA) 5.83 5.83 5.83 5.83 Branched aliphatic urethane
dimethacry- late (7,7,9-trimethyl- 4,13-dioxo-3,14
dioxa-5,12-diazahexa- decane-1,16-diol dimethacrylate) Ethoxylated
bisphenol 6.99 6.99 6.99 6.99 A dimethacrylate* (Lucirin TPO) 0.10
0.10 2,4,6-Trimethyl- benzoyldiphenyl phosphine oxide Methacrylic
acid 0.085 0.085 0.06 0.06 Butylated 0.004 0.004 0.003 0.003
hydroxytoluene N,N-dimethylamino- 0.163 0.163 0.117 0.117 neopentyl
acrylate gamma-methacryloxy- 0.050 0.050 0.036 0.036 propyl
trimethoxy silane (Camphorquinone) 0.048 0.048 0.034 0.034
bicyclo[2,2,1] heptane-2,3-dione- 1,1,7-trimethyl-(IS) Amorphous
Silica 0.50 0.50 (silaned) Barium fluoro 69.50 70.00 69.50 70.00
alumino boro- silicate glass*** Titanium Dioxide** 0.017 0.050
0.017 0.050 Yellow Iron Oxide 0.005 0.005 7055 Cromophtal Red-BRN
0.0003 0.0003 2-napthalenecarbox- amide, N,N'-(2-chloro-
1,4-phenylene) bis{4- {(2,5-dichlorophenyl) azo}-3-hydroxy-} Black
Iron Oxide 0.001 0.001 7053 Lumilux Blue LZ 0.001 0.001 0.001 0.001
fluorescing agent (di- hydroxy terepthalate acid ester) Total % 100
100 100 100 *SR348 - purchased from Sartomer Company, Inc.
**Titanium Dioxide is one of three different types of TiO.sub.2:
Titanox 328, 3328, 325 ***Particles have one or more different
average particle sizes and are selected from average particles
sizes range from 0.1 micrometer to 10 micrometers.
Example 5
Laboratory Fabricated Crown Requiring Reline to Mount
[0069] A silicone matrix putty was molded and shaped over a
targeted tooth and area on a dental model requiring a crown. The
putty was molded over the targeted tooth so that it extended about
2 mm beyond the tooth's margins. The matrix putty was allowed to
harden. Then, the hardened putty was removed from the model. After
the dental model was adequately reduced, a thin coat of model
separator (oxygen barrier coating available from Dentsply
International) was applied to the prepared areas.
[0070] Then, a small amount of heated enamel resin (prepared in
above Example 4A) was applied into the incisal area of the hardened
matrix putty. A hot spatula was used to spread out the resin and
remove any excess material from the matrix. Then, a sufficient
amount of the dentin resin (prepared in above Example 4B) was
extruded from a heated syringe to fill the matrix. Thus, the matrix
was filled with a composite resin material. Immediately thereafter,
the filled matrix was placed over the prepared dental model and
excess material was allowed to escape around the margins. Once
seated, the composite material was allowed to set for approximately
one (1) to three (3) minutes to form the crown. The matrix was then
removed from the model leaving the resulting crown in place. After
the matrix was removed, excess composite material around the
margins and adjacent teeth on the model was carefully removed. At
this point, the crown can be easily shaped, contoured, occluded and
adjusted as needed since it is shape-stable and in an uncured
state.
[0071] The model with the mounted crown was then placed inside of a
light-curing oven and irradiated with curing light and heated in
accordance with a pre-determined curing cycle. The crown was then
removed from the model and shaped and contoured as needed. Finally,
a thin layer of a visible light curing sealer was applied to the
surface of the crown and the crown was cured for about two minutes.
The finished crown was relined and cemented on a crown-prepped
tooth in a patient's mouth.
Example 6
Laboratory Fabricated Crown Mounted Using Dental Cement
[0072] In this example, two dental models were made, a first model
containing the unprepared tooth and a second model containing the
crown-prepped tooth. A silicone matrix putty was molded and shaped
over the targeted area of the first dental model. The putty was
molded over the targeted tooth so that it extended about 2 mm
beyond the tooth's margins. The matrix putty was allowed to harden.
Then, the hardened putty was removed from the model. A thin layer
of oxygen barrier coating was applied to the second dental
model.
[0073] Then, a small amount of heated enamel resin (prepared in
above Example 4C) was applied into the incisal area of the hardened
matrix putty. A hot spatula was used to spread out the resin and
remove any excess material from the matrix. Then, a sufficient
amount of the dentin resin (prepared in above Example 4D) was
extruded from a heated syringe to fill the matrix. Thus, the matrix
was filled with a composite resin material. Immediately thereafter,
the filled matrix was placed over the second dental model
(containing the crown-prepped tooth) and excess material was
allowed to escape around the margins. Once seated, the composite
material was allowed to set for approximately one (1) to three (3)
minutes to form the crown. The matrix was then removed from the
model leaving the resulting crown in place. After the matrix was
removed, excess composite material around the margins and adjacent
teeth was carefully removed. The resulting crown can be easily
shaped, contoured, occluded and adjusted as needed since it is
shape-stable and in an uncured state.
[0074] A thin layer of a visible light curing sealer was applied to
the surface of the crown. The model with the mounted crown was then
placed inside of a light-curing oven and irradiated with curing
light and heated in accordance with a pre-determined curing cycle.
The resulting crown was finished and polished as needed. Then, the
crown was cemented on a crown-prepped tooth in a patient's
mouth.
Example 7
Laboratory Fabricated Bridge Requiring Reline
[0075] A silicone matrix putty was molded and shaped over the area
of a dental model requiring a dental bridge. The matrix putty was
allowed to harden. Then, the hardened putty was removed from the
model. After the dental model was adequately reduced, a thin layer
of oxygen barrier coating was applied to the prepared areas of the
model.
[0076] Then, a small amount of heated enamel resin (prepared in
above Example 4C) was applied into the incisal area of the hardened
matrix putty. A hot spatula was used to spread out the resin and
remove any excess material from the matrix. Then, a sufficient
amount of the dentin resin (prepared in above Example 4D) was
extruded from a heated syringe to fill the matrix. Thus, the matrix
was filled with a composite resin material. Immediately thereafter,
the filled matrix was placed over the dental model and excess
material was allowed to escape around the margins. Once seated, the
composite material was allowed to set for approximately two (2) to
five (5) minutes to form the bridge. The matrix was then removed
from the model leaving the resulting bridge. After the matrix was
removed, excess composite material around the margins and adjacent
teeth was carefully removed. The resulting bridge can be easily
shaped, contoured, occluded and adjusted as needed.
[0077] The model with the mounted bridge was then placed inside of
a light-curing oven and irradiated with curing light and heated in
accordance with a pre-determined curing cycle. The bridge was then
removed from the model and shaped and contoured as needed. Finally,
a thin layer of a visible light curing sealer was applied to the
surface of the bridge and the bridge was cured for about two
minutes. The finished bridge was relined and cemented on the
prepared teeth in a patient's mouth.
Example 8
Laboratory Fabricated Bridge Mounted Using Dental Cement
[0078] In this example, two dental models were made, a first model
containing the unprepared tooth and a second model containing the
bridge-prepped teeth.
[0079] A silicone matrix putty was molded and shaped over the
targeted area of the first dental model. The matrix putty was
allowed to harden. Then, the hardened putty was removed from the
model. A thin layer of oxygen barrier coating was applied to the
second dental model.
[0080] Then, a small amount of heated enamel resin (prepared in
above Example 4C) was applied into the incisal area of the hardened
matrix putty. A hot spatula was used to spread out the resin and
remove any excess material from the matrix. Then, a sufficient
amount of the dentin resin (prepared in above Example 4D) was
extruded from a heated syringe to fill the matrix. Thus, the matrix
was filled with a composite resin material. Immediately, the filled
matrix was placed over the second dental model (containing the
bridge-prepped teeth) and excess material was allowed to escape
around the margins. Once seated, the composite material was allowed
to set for approximately two (2) to five (5) minutes to form the
provisional or long term bridge. The matrix was then removed from
the model leaving the resulting bridge. After the matrix was
removed, excess composite material around the margins and adjacent
teeth was carefully removed. The resulting bridge can be easily
shaped, contoured, occluded and adjusted as needed. Then, a thin
layer of visible light curing sealer was applied to the surface of
the bridge. The model was placed in a light-curing oven and
irradiated with curing light and heated in accordance with a
pre-determined curing cycle. The resulting bridge was finished and
polished as needed. The bridge was then cemented on the prepared
teeth in the patient's mouth.
Example 9
Chairside Crown Mounted Using Dental Cement
[0081] A quadrant impression of the area for receiving a crown in a
patient's mouth was taken prior to preparation of the tooth. The
margin areas of the impression were trimmed to within 2 mm of the
tooth margin areas to allow easy escape of excess material. The
tooth for receiving the crown was dry prepared and lightly
lubricated with Vaseline or a similar separating medium (including
light-curable separating medium). A small amount of the heated
enamel resin of Example 4A was applied into the incisal area of the
impression. A spatula was used to spread out the resin and remove
any excess in the impression. A desired amount of the dentin resin
of Example 4B was extruded from a heated compule or syringe to fill
the impression. The impression was placed immediately onto the
prepared tooth and excess material was allowed to escape around the
margins. After the impression was removed, excess material around
the margins and adjacent teeth was carefully removed. The crown can
be bitten, shaped, contoured, occluded and adjusted as needed.
Then, the crown was removed from the prepared tooth. Die silicone
was injected into the cavity of the crown to form a die. After a
sealer was applied, the crown was cured in an Eclipse.RTM.
light-curing unit (available from Dentsply International) for 10
minutes. The crown was finished and polished. It was then cemented
on a crown-prepped tooth in the patient's mouth.
Example 10
Chairside Crown Mounted Using Dental Cement
[0082] A quadrant impression of the area for receiving a crown in a
patient's mouth was taken prior to the preparation of the tooth.
The margin areas of the impression were trimmed to within 2 mm of
the tooth margin areas to allow easy escape of excess material. The
tooth for receiving crown was dry prepared and lightly lubricated
with Vaseline. A small amount of the enamel resin of Example 4C was
applied into the incisal area of the impression. A hot spatula was
used to spread out the resin and remove any excess in the
impression. A desired amount of the dentin resin of Example 4D was
extruded from a heated compule or syringe to fill the impression.
The impression was immediately placed onto the prepared tooth and
excess material was allowed to escape around the margins. After the
impression was removed, excess material around the margins and
adjacent was carefully removed. The crown was removed from the
prepared tooth. After a sealer was applied, the crown was cured in
an Eclipse.RTM. light-curing unit (Dentsply) for 10 minutes. The
crown was finished and polished. It was then cemented on a
crown-prepped tooth in the patient's mouth.
Example 11
Chairside Crown Made Using a Partial Light-Curing Process
[0083] A quadrant impression of the area for receiving a crown in a
patient's mouth was taken prior to the preparation of a tooth. The
margin areas of the impression were trimmed to within 2 mm of the
tooth margin areas to allow easy escape of excess material. The
tooth for receiving crown was dry prepared and lightly lubricated
with Vaseline. A small amount of the enamel resin of Example 4A was
applied into the incisal area of the impression. A hot spatula was
used to spread out the resin and remove any excess in the
impression. A desired amount of the dentin resin of Example 4B was
extruded from a heated compule or syringe to fill the impression.
Immediately, the impression was placed onto the prepared tooth and
excess material was allowed to escape around the margins. The
impression was removed. Then, the crown was partially cured with a
handheld light for 20 seconds. A QHL75 curing light (Dentsply) was
used. (Alternatively, other suitable dental curing lights also may
be used.) The crown was then removed from the mouth and the margins
were finished to desired shape. After a sealer was applied, the
crown was fully cured in an Eclipse.RTM. light-curing unit
(Denstply) for 10 minutes. The crown was then cemented on the
crown-prepped tooth in the patient's mouth.
Example 12
Chairside 3 Unit Bridge Mounted Using Dental Cement
[0084] A quadrant impression of the area for receiving a dental
bridge in a patient's mouth was taken prior to the preparation and
extraction of teeth. The margin areas of the impression were
trimmed to within 2 mm of the tooth margin areas to allow easy
escape of excess material. Teeth were extracted and the teeth for
receiving the bridge were dry prepared and lightly lubricated with
Vaseline. A small amount of the enamel resin of Example 4C was
applied into the incisal areas of the impression. A spatula was
used to spread out the resin and remove any excess in the
impression. A desired amount of the dentin resin of Example 4D was
extruded from a heated syringe to fill the impression. Immediately,
the impression was placed onto the prepared teeth and tooth
extracted area and excess material was allowed to escape around the
margins. After the impression was removed, the excess material
around the margins and adjacent teeth was carefully removed. The
resulting bridge can be bitten, shaped, contoured, occluded and
adjusted as needed. The bridge was removed and die silicone was
injected into the cavities of the crowns and under the pontic to
form a supporting model. After a sealer was applied, the bridge was
cured in and Eclipse.RTM. light unit (Dentsply) for 10 minutes. The
bridge was finished and polished. It was then cemented on the
prepared teeth in the patient's mouth.
Example 13
Chairside 3 Unit Bridge Made Using a Partial Light-Curing
Process
[0085] A quadrant impression of the area for receiving a dental
bridge in a patient's mouth was taken prior to the preparation and
extraction of teeth. The margin areas of the impression were
trimmed to within 2 mm of the tooth margin areas to allow the easy
escape of excess material. Teeth were extracted and the teeth for
receiving the bridge were dry prepared and lightly lubricated with
Vaseline. A small amount of the enamel resin of Example 4A was
applied into the incisal areas of the impression. A hot spatula was
used to spread out the resin and remove any excess in the
impression. A desired amount of the dentin resin of Example 4B was
extruded from a heated syringe to fill the impression. Then, the
impression was immediately placed onto the prepared teeth and tooth
extracted area and excess material was allowed to escape around the
margins. After the impression was removed, excess material around
the margins and adjacent teeth carefully removed. The resulting
bridge can be bitten, shaped, contoured, occluded and adjusted as
needed. The bridge was partially cured with a handheld light for 60
seconds. (QHL75 curing light from Dentsply) The bridge was removed
from the prepared teeth and the margins were finished to desired
shapes. Die silicone was injected into the cavities of the crowns
and under the pontic to form a supporting model (Optionally, the
partially cured bridge might can be cured in a light-curing unit
without using die silicone). After a sealer was applied, the bridge
was cured in an Eclipse.RTM. light-curing unit (Dentsply) for 10
minutes. The bridge was finished and locally polished. It was then
cemented on the prepared teeth in the patient's mouth.
[0086] Workers skilled in the art will appreciate that various
modifications can be made to the embodiments and description herein
without departing from the spirit and scope of the present
invention. It is intended that all such modifications be covered by
the appended claims.
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