U.S. patent application number 13/231301 was filed with the patent office on 2012-01-05 for multifunctional acrylates used as cross-linkers in dental and biomedical self-etching bonding adhesives.
Invention is credited to David G. Charlton, James C. Ragain, JR., Amer Tiba.
Application Number | 20120003611 13/231301 |
Document ID | / |
Family ID | 42398231 |
Filed Date | 2012-01-05 |
United States Patent
Application |
20120003611 |
Kind Code |
A1 |
Ragain, JR.; James C. ; et
al. |
January 5, 2012 |
MULTIFUNCTIONAL ACRYLATES USED AS CROSS-LINKERS IN DENTAL AND
BIOMEDICAL SELF-ETCHING BONDING ADHESIVES
Abstract
This invention describes an adhesive used for bonding dental and
medical biomaterials to hard tissues via a molecular bridge formed
from calcium-reactive amines and acrylic or methacrylic ester
monomers to hard tissues such as enamel, dentin, and bone. This
formulation consists of an acid-stable polymerizable compound with
multi-functional acrylate cross-linkers. This formula provides good
self-adherence without prior preparation of the hard tissue
substrates. The formulation can contain chemical- and/or
light-activated free-radical initiators.
Inventors: |
Ragain, JR.; James C.;
(US) ; Tiba; Amer; (Lake Bluff, IL) ;
Charlton; David G.; (Gurnee, IL) |
Family ID: |
42398231 |
Appl. No.: |
13/231301 |
Filed: |
September 13, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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12362622 |
Jan 30, 2009 |
8053487 |
|
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13231301 |
|
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Current U.S.
Class: |
433/228.1 ;
523/118 |
Current CPC
Class: |
A61K 6/30 20200101; A61K
6/887 20200101; A61K 6/887 20200101; A61K 6/30 20200101; C08L 33/00
20130101; C08L 33/00 20130101; C08L 33/00 20130101; A61K 6/30
20200101; C08L 33/00 20130101; A61K 6/887 20200101 |
Class at
Publication: |
433/228.1 ;
523/118 |
International
Class: |
A61C 5/04 20060101
A61C005/04; A61K 6/00 20060101 A61K006/00 |
Claims
1. An adhesive composition comprising a mixture of: a. one or more
polymerizable acrylic or methacrylate compounds; b. one or more
hydrophilic acrylate or methacrylate compounds; c. one or more
calcium reactive amines; d. one or more acrylic or methacrylic
esters, wherein said esters form a multifunctional acrylic
cross-link between said polymerizable acrylic or methacrylic
compounds; e. one or more polymerization initiators; and f. filler
materials, wherein said filler materials contain glass powder and
fluoride-containing compounds.
2. The adhesive composition of claim 1, wherein said polymerizable
acrylic compounds are: ethyl acrylate, propyl acrylate, isopropyl
acrylate, 2-hydroxyethyl acrylate, hydroxypropyl acrylate,
tetrahydrofurfuryl acrylate, glycidyl acrylate, glycerol mono- and
di-acrylate, ethyleneglycol diacrylate, polyethyleneglycol
diacrylate, neopentyl glycol diacrylate, trimethylolpropane
triacrylate, mono-, di-, tri-acrylate, mono-, di-, tri-, and
tetra-acrylates of pentacrythritol and dipentaerythritol,
1,3-butanediol diacrylate, 1,4-butanedioldiacrylate, 1,6-hexane
diol diacrylate,
2,2'-bis[3(4-phenoxy)-2-hydroxypropane-1-acrylate]propane, 2,2'
bis(4-acryloxyphenyl)propane,
2,2'-bis[3(4-phenoxy)-2-hydroxypropane-1-acrylate]propane,
dipentaerthritol pentaacrylate esters (SR 399) and dipentaerthritol
pentaacrylate esters (SR 399 LV).
3. The adhesive composition of claim 1, wherein said polymerizable
methacrylate compounds include: methacrylates, ethyl methacrylate,
propyl methacrylate, isopropyl methacrylate, tetrahydrofurfuryl
methacrylate, glycidyl methacrylate, the diglycidyl methacrylate of
bis-phenol A
(2,2-Bis[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]propane)
(BisGMA), glycerol mono- and di-methacrylate, ethyleneglycol
dimethacrylate, polyethyleneglycol dimethacrylate, triethylene
glycol dimethacrylate (TEGDMA), neopentylglycol dimethacrylate,
trimethylol propane trimethacrylate, mono-, di-, tri-, and
tetra-methacrylates of pentacrythritol and dipentaerythritol,
1,3-butanediol dimethacrylate, 1,4-butanediol dimethacrylate,
Bis[2-(methacryloyloxy)ethyl]phosphate (BisMEP),1,6-hexanediol
dimethacrylate, 2-2'-bis(4-methacryloxyphenyl)propane,
2,2'-bis[4(2-hydroxy-3-methacryloxy-phenyl)]propane, 2,2'
bis[4(2-hydroxy-3acryloxyphyenyl)propane,
2,2'-bis(4-methacryloxyethoxyphenyl)propane,
2,2'-bis(4-acryloxyethoxyphenyl)propane,
2,2'-bis(4-methacryloxypropoxyphenyl)propane,
2,2'-bis(4-acryloxypropoxyphenyl)propane,
2,2'-bis(4-methacryloxydiethoxyphenyl)propane,
2,2'-bis(4-acryloxydiethoxyphenyl)propane,
2,2'-bis[3(4-phenoxy)-2-dydroxypropane-1-methacrylate]propane.
4. The adhesive composition of claim 1, wherein said hydrophilic
acrylate compounds are 2-hydroxyethyl acrylate, and hydroxypropyl
acrylate.
5. The adhesive composition of claim 1, wherein said methacrylate
compound is hydroxyethylmethacrylate (HEMA).
6. The adhesive composition of claim 1, wherein said calcium
reactive amines are ethyl-4-Dimethylaminobenzoate (EDMAB) and
4-(dimethylamino) benzoic acid (DMABA).
7. The adhesive composition of claim 1, wherein said acrylic ester
is SR 399 LV.
8. The adhesive composition of claim 1, wherein said methacrylic
ester is bis[2-(methacryloyloxy)ethyl]phosphate (BisMEP).
9. The adhesive composition of claim 1, wherein said polymerization
initiator is chemical initiator, photo-initiator, or combination
thereof.
10. The adhesive composition of claim 9, wherein said chemical
initiator is BPO.
11. The adhesive composition of claim 9, wherein said
photo-initiator are selected from the group consisting of diphenyl
(2,4,6-trimethylbenzoyl)phosphine oxide and camphorquinone
(CQ).
12. The adhesive composition of claim 1, wherein said glass powder
is a mixture of glass particles 0.02 to 40 microns in size.
13. The adhesive composition of claim 1, wherein said adhesive is a
bonding agent between a substrate and a hard tissue.
14. The composition of claim 13, wherein said hard tissue is
selected from the group consisting of enamel, bone, and dentin.
15. The adhesive composition of claim 13, wherein said substrate is
selected from the group consisting of acrylates, composite resins,
ceramics, and metals.
16. The adhesive composition of claim 1, wherein said adhesive is a
bonding agent that can be used for the stabilization of avulsed,
inverted, or luxated teeth to adjacent unaffected teeth.
17. The adhesive composition of claim 1, wherein a. said
polymerizable methacrylate compound is TEGDMA; b. said hydrophilic
methacrylate compound is HEMA; c. said calcium reactive amine is
EDMAB; d. said acrylic or methacrylic ester are BisMEP and SR399LV;
e. said polymerization initiator are CQ and BPO; f. said glass
powder is Ba Glass. g. said filler materials are GI SP2034, Ba
Glass, Aerosil 200; and h. and fluoride-containing compound is GI
SP 2034.
18. A method of dental restoration using the adhesive composition
of claim 1, comprising a. blending said mixture thoroughly at a
powder to liquid ratio of 3:1 by weight; b. applying said mixture
to a dental substrate; c. allowing said mixture to harden; d.
repeating steps a-c until said mixtures resembles the physiological
shape of the missing teeth.
19. The adhesive composition of claim 1, wherein said filler
materials comprise Barium, Aerosil 200, Pigments, Calcium
Fluoroaluminosilicate glass, Silica, Alumina, Aluminum Fluoride,
Calcium Fluoride, Sodium Fluoride, Aluminum Phosphate, Calcium,
Strontium, Zinc, Sodium, Potassium, Lanthanum, and
Alumino-silicates or any combination thereof.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. patent application
Ser. No. 12/362,622 filed Jan. 30, 2009, which claims priority to
U.S. Patent Application No. 60/025,045 filed Jan. 31, 2008.
BACKGROUND OF INVENTION
[0002] 1. Field of Invention
[0003] This invention relates to a biomaterial and more
specifically a high molecular weight, multifunctional acrylate
cross-linking composition that, when formulated with other
compounds will self-etch and self-adhere to hard tissues, such as
enamel, dentin, and bone.
[0004] 2. Description of the Related Art
[0005] The use of synthetic materials to expedite healing is
becoming more widespread. A burgeoning area of growth is the use of
relatively inert hardening agents for use as adhesives or as a
substitute for hard tissue. Hard tissue typically means tissues
that have become mineralized, or tissue having a firm intercellular
substance, such as enamel, dentin, cartilage, and bone. Bone and
tooth structure, such as enamel, dentin and cementum, have certain
compositional and morphologic similarities. Like enamel and dentin,
bone consists primarily of inorganic material, which is almost
exclusively in the form of an apatite of calcium and phosphate that
resembles hydroxylapatite, and a lesser amount of organic material,
which is 90% collagen. Morphologic similarities also exist. Enamel
and dentin both contain tubules which meet their respective
surfaces at a perpendicular angle, while bone contains tube-like
Haversian Canals. The Haversian Canals run parallel to the bone's
surface, but Volkmann's Canals, which run from them meet the bone
surface at a perpendicular angle.
[0006] Teeth that are fractured or have lost dental restorations
often involve exposed dentin. These exposed teeth are prone to
tooth decay, and patients usually experience pain. For treatment
purposes, the exposed teeth are usually restored with permanent
dental restorations. However, definitive dental restorations often
are not performed in a timely fashion. In these cases, temporary
dental restorations (fillings) are usually placed onto the exposed
teeth. There are a variety of restorative dental materials that can
be used as temporary fillings.
[0007] The materials most commonly chosen as temporary fillings are
zinc oxide-eugenol (ZOE) compounds, glass-ionomer materials, and
resin-based dental materials. These filling materials are retained
in teeth through mechanical retention and/or chemical bonding with
the tooth structure.
[0008] ZOE fillings require mechanical retention. These materials
are relatively weak compared to the other types of temporary
filling materials.
[0009] Glass-ionomer dental filling materials can bond to tooth
structure without the need of a separately applied bonding agent.
In addition, glass-ionomer materials release fluoride, which
strengthens the surface of the tooth. A disadvantage of
glass-ionomer dental filling materials is their relatively long
setting time and concomitant sensitivity to moisture. Moisture
exposure can result in premature disintegration of the
glass-ionomer material and reduce bond strength. Furthermore, the
chemical bond formed between glass-ionomers and tooth structure is
relatively weak.
[0010] Resin-based filling materials can be bond to teeth using
both mechanical and chemical retentions. Bonding of resin-based
dental materials to tooth structure is currently achieved through a
multi-step process. A dentin-enamel bonding agent must be applied
to the tooth prior to placing the dental material. Applying this
bonding agent often requires multiple steps and a significant
amount of clinical time. Misapplication of the bonding material may
also occur.
[0011] In general, retention of temporary fillings through chemical
bonding is quicker, requires less preparation of the tooth, and is
usually stronger. Often teeth can be temporarily restored with
dental materials using only chemical bonding. Acid etching of the
tooth surface are often performed to improve adhesion of
resin-based filling materials by promoting mechanical retention.
However, many acid-etching agents must be removed prior to
application of the bonding agents, which further increases clinical
time. Acid etching can also cause dental sensitivity in some
patients.
[0012] There are dental restorative materials on the market that
are self-etching adhesives. These compositions generally use water
and/or organic solvents and take a liquid form. Consequently, these
self-etching adhesives have a short shelf-life, which may pose
additional problems for storage. For example, these materials may
experience a premature setting in extreme conditions such as those
presented in a desert battlefield. Furthermore, many of these
formulations require multiple applications of a single component or
application of several separate components. Therefore, they require
more clinical time to apply than the inventive formulation.
[0013] U.S. Pub. No. 2007/0244215 A1 by Junjie Sang, describes a
one-component self-etching dental adhesive, which requires a simple
one-coat application, without the need of separate acid-etching,
priming or bonding step. This is achieved through the employment of
a hydrolytically stable, acidic, high-strength adhesive monomer
(such as PENTA) with a stable, bifunctional, hydrophilic monomer
(such as AHPMA) that yields greater cross-linking. However, this
material lacks filler content and does not provide a fluoride
source.
[0014] U.S. Pub. No. 2007/0155853 A1 by Chen et al., is another
one-component self-etching self-priming dental adhesive
composition. The formulation contains BisGMA
(2,2-bis[4-(2-hydroxy-3-methacryloylpropoxy)-phenyl]-propane), DPPA
(dipentaerythrytol pentaacrylate), GDM (glycerol dimethacrylate),
GPDM (glycerol phosphate dimethacrylate), and PMGDM (pyromellitic
glycerol dimethacrylate). The formulation contains both water and
an organic solvent such as acetone or ethanol. Additional clinical
steps and resin materials are required to bond composite resins to
dentin or enamel.
[0015] U.S. Pub. No. 2006/0069181 by Thalaker et al. presents a
liquid self-etch adhesive that is composed of a carboxylic acid
functional polymer and water. This dental adhesive composition
consists of two liquid components and contains no fluoride
releasing agents or glass fillers. Additional clinical steps and
resin materials are required to bond composite resins to dentin or
enamel.
[0016] U.S. Pub. No. 2007/0248927 A1 by Luchterhandt et al. is a
self-adhesive composition based on polyacrylate, Kayamer, MH-P
(Methacryloxyhexyl phosphate), MO-P (8-Methacryloxyoctyl
phosphate), and MD-P (10-Methacryloxydecyl phosphate) polymerizable
compounds. This formula is only photo-curable and requires
additional priming step and curing equipment.
[0017] U.S. Pub. No. 2007/0203257 A1 by Xuejun Qian, describes a
two-part paste/paste self-etch adhering dental composition based on
UDMA (reaction product of 2-hydroxyethyl methacrylate with
2,4,4-trimethylhexane diisocyanate), BisGMA, GDM-P
(glyceryldimethacrylate phosphate), and GDM
(glyceryidimethacrylate). It also contains a solvent, which may
increase the oxidation rate of the formula. The formula does not
contain any fluoride releasing agent.
[0018] U.S. Pub. No. 2005/0277706 A1 by Han et al., describes a
highly functional dental adhesive that is based on multifunctional
pre-polymer mixture of BisGMA, Tri-GMA, 4-MBTA
(4-methacryloxybutyltrimellitic anhydride), MDP, HPMA and water.
This adhesive is only photo-curable, which requires additional
curing equipment. In addition, this formula contains a maximum of
five percent filer material and does not include a fluoride
releasing agent.
SUMMARY OF THE INVENTION
[0019] The current invention aims to improve existing technology.
The inventive formulation has multiple advantages over the prior
art. It is a self-etching material, which can be applied to tooth
in a single step without the need of a primer. The inventive
formulation is also dual-curable, which means it can be photo-cured
or chemically hardened. Chemical setting allows for curing in deep
areas where light is not effective and eliminates the need of
additional equipment in situations where such equipment are not
readily available. Furthermore, the inventive formula contains
fluoride releasing materials and up to 75% of glass fillers in a
combination of different particle sizes. The inclusion of fluoride
releasing agent and high percentage of glass particles of varying
sizes improve physical and mechanical properties of the final set
material. Additionally, the inventive formula is a power and liquid
combination format and contains no solvent, which may increase
shelf-life and prevents premature setting.
[0020] An object of this invention is an acid-stable polymerizable
composition with multi-functional acrylate cross-linkers suitable
as a dental/biomedical self-adhesive bonding material.
[0021] Another object of the invention is a self-etching,
acid-stable polymerizable composition with multifunctional acrylate
cross-linkers, which provides good self-adherence without prior
preparation of the hard tissue or the substrates.
[0022] An additional object of the invention is a self-etching,
acid-stable polymerizable adhesive material, which contains
chemical and/or light-activated free-radical initiators that allows
the final material to set within a relatively short time,
approximately 4-4.5 minutes at 37.degree. C.
[0023] A further object of the invention is a fluoride-releasing
composition that can be used as a self-etching, self-adhesive
bonding agent between hard tissues (enamel, dentin, or bone) and
dental and biomedical substrates.
[0024] Another object of this invention is a method of bonding
dental and medical biomaterials via a molecular bridge formed from
calcium reactive amines and acrylic or methacrylic ester monomers
to hard tissues such as enamel, dentin, and bone.
DETAIL DESCRIPTION OF THE INVENTION
[0025] This invention is directed to an adhesive composition that
can be used in bonding dental and medical biomaterials to hard
tissues via a molecular bridge formed from calcium reactive amines
and acrylic or methacrylic ester monomers contained in the
biomaterials and enamel, dentin, and bone. The adhesive composition
may be used as: (i) temporary dental restorative or dressing
material, (ii) long-term dental restorative (filling) material
through the incorporation of various inorganic filler materials,
(iii) luting cement, for bonding fixed dental prosthetic devices,
such as crowns and bridges, to dentin and enamel, or (iv) luting
cement for bonding orthodontic brackets to enamel; (v) stint for
stabilizing avulsed, inverted, or luxated teeth; (vi) bone cement,
for bonding implant prostheses and skull implants to bone; (vii)
liner or base under amalgam dental restorations.
[0026] This adhesive composition comprises of an acid-stable
polymerizable compound with multi-functional acrylate cross-linkers
and provides good self-etching and self-adherence without prior
preparation of the hard tissue substrates, such as separate acid
etching or priming steps. In general, the adhesive composition
comprises a mixture of one or more polymerizable acrylic or
methacrylate compounds, one or more hydrophilic acrylate or
methacrylate compounds, one or more calcium reactive amines, one or
more acrylic or methacrylic esters, one or more polymerization
initiators, glass powder, fluoride-containing compounds, and other
filter materials. The esters functions both as an acrylic or
methacrylate compound that polymerizes with the other a acrylic or
methacrylate compounds and as a cross-linker, which forms a salt
bridge with calcium in the dentin or enamel. The preferred
composition could vary slightly for different dental and biomedical
applications. Considerations would include varying the formula to
affect properties such as viscosity, flowability, working time,
setting time, film thickness, and bond strength. Standard
mechanical and material testing may be performed to assess these
formulations for their designed application. In general, the
laboratory tests that may be performed to measure the physical and
mechanical properties of the inventive compound, which include
compressive strength, DTS, flexural strength, shear bond strength,
and film thickness. One of skill in the art will appropriate that
the above material properties can be adjusted as appropriate for
each dental/biomedical application.
[0027] In a preferred embodiment, the composition contains two
components: a liquid component and a powder component. The liquid
component contains at least one polymerizable acrylic or
methacrylate compound, and one or more hydrophilic acrylate or
methacrylate compounds. Examples of suitable hydrophilic acrylates
are 2-hydroxyethyl acrylate and hydroxypropyl acrylate. An example
of a hydrophilic methacrylate compound is hydroxyethylmethacrylate
(HEMA). Examples of polymerizable acrylates are: ethyl acrylate,
propyl acrylate, isopropyl acrylate, 2-hydroxyethyl acrylate,
hydroxypropyl acrylate, tetrahydrofurfuryl acrylate, glycidyl
acrylate, glycerol mono- and di-acrylate, ethyleneglycol
diacrylate, polyethyleneglycol diacrylate, neopentyl glycol
diacrylate, trimethylolpropane triacrylate, mono-, di-,
tri-acrylate, mono-, di-, tri-, and tetra-acrylates of
pentacrythritol and dipentaerythritol, 1,3-butanediol diacrylate,
1,4-butanedioldiacrylate, 1,6-hexane diol diacrylate, 2,2%
bis[3(4-phenoxy)-2-hydroxypropane-1-acrylate]propane,
2,2'bis(4-acryloxyphenyl)propane,
2,2'-bis[3(4-phenoxy)-2-hydroxypropane-1-acrylate]propane,
dipentaerthritol pentaacrylate esters (SR 399) and dipentaerthritol
pentaacrylate esters (SR 399 LV).
[0028] Polymerizable methacrylate compounds may be: methacrylates,
ethyl methacrylate, propyl methacrylate, isopropyl methacrylate,
tetrahydrofurfuryl methacrylate, glycidyl methacrylate, the
diglycidyl methacrylate of bis-phenol A
(2,2-Bis[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]propane)
(BisGMA), glycerol mono- and di-methacrylate, ethyleneglycol
dimethacrylate, polyethyleneglycol dimethacrylate, triethylene
glycol dimethacrylate (TEGDMA), neopentylglycol dimethacrylate,
trimethylol propane trimethacrylate, mono-, di-, tri-, and
tetra-methacrylates of pentacrythritol and dipentaerythritol,
1,3-butanediol dimethacrylate, 1,4-butanediol dimethacrylate,
Bis[2-(methacryloyloxy)ethyl]phosphate (BisMEP),1,6-hexanediol
dimethacrylate, 2-2'-bis(4-methacryloxyphenyl)propane,
2,2'-bis[4(2-hydroxy-3-methacryloxy-phenyl)]propane, 2,2'
bis[4(2-hydroxy-3acryloxyphyenyl)propane,
2,2'-bis(4-methacryloxyethoxyphenyl)propane,
2,2'-bis(4-acryloxyethoxyphenyl)propane,
2,2'-bis(4-methacryloxypropoxyphenyl)propane,
2,2'-bis(4-acryloxypropoxyphenyl)propane,
2,2'-bis(4-methacryloxydiethoxyphenyl)propane,
2,2'-bis(4-acryloxydiethoxyphenyl)propane,
2,2'-bis[3(4-phenoxy)-2-dydroxypropane-1-methacrylate]propane.
[0029] The liquid component also contains an amine that is capable
of forming a salt bridge between the calcium ions in the dentin and
acrylic or methacrylic esters. An example of a methacrylate ester
is Bis[2-(methacryloyloxy)ethyl]phosphate (BisMEP). The preferred
amines include but are not limited to aromatic amines such as
4-(dimethylamino)benzoic acid (DMABA) and ethyl
4-dimethylaminobenzoate (EDMAB). The selection of the appropriate
amine is critical. Unlike other amines found in other dual-cure
(chemical- and visible-light photo-curing functions together in one
formulation) and photo-cure dental and biomedical adhesive
materials, the amine used in the preferred embodiment (EDMAB) is
stable in an acidic environment.
[0030] Furthermore, although some aromatic amines, such as DMABA
and EDMAB, have been experimentally determined to be effective at
permitting adherence of the polymerizable acrylate to dentin,
others, such as 2,2'-(p-tolylimino)diethanol (P-TID) is not
effective.
[0031] In addition to the acrylates and amines, the liquid
component of the inventive formulation contains one or more acrylic
ester or methacrylic ester. The esters function as an ester and as
an acrylic or methacrylate compound and form a cross-link between
the polymerizable acrylic or methacrylate compounds. In the
preferred embodiment, dipentaerthritol pentaacrylate esters (SR 399
LV) are used as this cross-linker. SR 399 LV is stable in an
acid-polymerizable formula that contains an acid such as
Bis[2-(methacryloyloxy)ethyl]phosphate (BisMEP) and an amine base
such as ethyl-4-dimethylaminobenzoate (EDMAB). SR 399 LV is easily
blended and co-polymerized with other methacrylates, such as
2,2-Bis[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]propane (BisGMA),
hydroxyethylmethacrylate (HEMA) and triethyleneglycol
dimethacrylate (TEGDMA), in the polymerizable formula. The
incorporation of dipentaerthritol pentaacrylate esters (SR 399 LV)
would self-etch hard tissues (such as enamel, dentin, and bone) and
crosslink the resin matrix upon setting, which enhances the resin
matrix upon polymerization (setting).
[0032] The powder component of the inventive composition contains
many filler materials, which include glass powder of various
particles sizes and one or more fluoride releasing agents. The
glass particles not only improve the physical and mechanical
properties of the composition but also serve as the base for the
acid-base reaction. The powder component may also contain other
filler materials such as Barium, Aerosil 200, Pigments, Silica,
Alumina, Aluminum Fluoride, Calcium Fluoride, Sodium Fluoride,
Aluminum Phosphate, Calcium, Strontium, Zinc, Sodium, Potassium,
Lanthanum, Alumino-silicates, other metal oxides, metal fluorides
and metal phosphates
[0033] The adhesive composition also uses at least one initiator to
permit photo or chemical initiation of curing, which could be
incorporated into either the liquid component or the powder
component. The formulation may, additionally, contain a
co-initiator to accelerate the curing process. In the preferred
embodiment, both a light-curing initiator camphorquinone (CQ) and a
self-curing initiator (BPO) are used. A curing inhibitor, such as
BHT, may also be included in the adhesive composition in order to
have a more controlled setting time.
[0034] Despite the chemicals identified in the preferred
embodiments, the inventive formulation also contemplates that other
chemicals, with similar characteristics, can be used. For example,
in place of BisMEP, 4 methacryloxyethyltrimellitic anhydride,
biphenyldimethacrylate, ethylene glycol methacrylate phosphate or
other esters of methacrylate can be used. Similarly, other
photo-initiators or chemical initiators, other than CQ can be used,
such as diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide. Also, in
place of DMABA, other amines could be substituted, such as ethyl
4-dimethylaminobezoate (EDMAB). Similarly, urethanedimethacrylate
can be substituted for BisGMA. Other dimethacrylate or
multimethacrylate diluents can be used instead of TEGDMA, such as
trimethylpropane trimethacrylate.
[0035] For either dental or biomedical applications, each compound
of the preferred formulation will fall within the following ranges
by weight.
Liquid Part
TABLE-US-00001 [0036] Chemical Formulation weight range (%) HEMA
(20-50) TEGDMA (10-30) BisMEP (5-25) SR 399 LV (5-25) BisGMA (5-30)
EDMAB (1-8) CQ (0.1-0.8) BHT(inhibitor) (0.01-0.06)
Powder Part:
TABLE-US-00002 [0037] Chemical Formulation weight range (%) GI
SP2034 (70-95) BPO (1-5) Ba Glass (1-5) Aerosil 200 (1-5) Pigment
(0.001-0.01)
Paste:
[0038] The powder and liquid were mixed in a powder: liquid ratio
of 3:1 by weight to form a paste and chemically hardened (set) 4 to
4.5 minutes later at 37.degree. C. Although, the inventive adhesive
composition may be used for many dental and medical applications,
for illustrative purposes, the following examples shows the
inventive adhesive material being used as a dental restoration
materials and as luting cement. A preferred formulation of the
invention composition for use as a dental restorative and luting
cement includes the following in the liquid and powder
components:
Liquid Component
TABLE-US-00003 [0039] Preferred Percentage Acronym Full Chemical
Name Source by Weight HEMA Hydroxyethylmethacrylate Aldrich .RTM.
33.68% TEGDMA Triethyleneglycol dimethacrylate Aldrich .RTM. 20.00%
BisMEP Bis[2- Aldrich .RTM. 20.00% (methacryloyloxy)ethyl]-
phosphate SR 399 LV Dipentaerthritol pentaacrylate Sartomer .TM.
10.00% esters BisGMA 2,2-Bis[4-(2-hydroxy-3- Aldrich .RTM. 10.00%
methacryloxypropoxy)phenyl- ]propane EDMAB
Ethyl-4-Dimethylaminobenzoate Aldrich .RTM. 6.00% BHT
2,6-Di-tert-butyl-4-methylphenol Aldrich .RTM. 0.02% CQ
Camphorquinone Aldrich .RTM. 0.30% Total = 100%
Powder Component
TABLE-US-00004 [0040] Preferred Percentage by Acronym Full Chemical
Name Source Weight GI SP2034 Glass powder TF grind Specialty
93.998% Glass Products Inc. Pigment Phthalocyanine green 7
Ultradent 0.002% Products Inc. BPO Dipentaerthritol Aldrich .RTM.
2.00% pentaacrylate esters Ba Glass 7% silanated 0.7 .mu.m Ba
Esstech, Inc. 2.00% glass Aerosil 200 Aerosil A200 Degussa 2.00%
Total = 100%
[0041] It is relatively easy to prepare compounds from this
formula. The powder and liquid were mixed in a powder:liquid ratio
of 3:1 by weight. Mixing requires thorough incorporation and
blending of the separate powder and liquid components. After
mixing, the paste sets (hardens) by way of an acid/base reaction
and a free-radical polymerization reaction in 4 to 4.5 minutes at
37.degree. C.
[0042] When used as dental restorative, the liquid and powder
components may be mixed and applied to the tooth structure
immediately in one step and simply wait for the restorative to set.
Alternatively, the liquid and powder components may be mixed and
placed onto the tooth in an incremental fashion. For example,
mixing a small amount of power and liquid components in the same
3:1 ratio by weight and apply the paste to the tooth surface. Once
the layer of paste hardens, a subsequent coat of adhesive may be
mixed and applied to the tooth. This incremental build-up of
adhesive materials allows the tooth to be restored its
physiological shape.
Example 1
Properties of the Adhesive Composition as Dental Restorative
Materials
[0043] The preferred inventive formulation is tested in the lab as
a dental restorative material. Laboratory tests shows that the
incorporation of the multi-functional acrylate cross-linking
compound dramatically enhanced the physical and mechanical
properties of the final set in the prototype dental material. When
using this formula as a bonding agent, the clinical pre-treatment
techniques of acid etching and priming the tooth structure are not
necessary. The material was tested against other classes of dental
materials commonly used as temporary fillings. Those materials were
FUJI IX.TM. GP fast (GC America, IL), KETAC-MOLAR.TM. (3M.TM. ESPE,
MN), and IRM (Dentsply Caulk, DE). The tests used were hardness
(Knoop), compressive strength, diametral tensile strength (DTS),
flexural strength, and dentin shear bond strength. Table 1 below
provides the results of those tests.
TABLE-US-00005 TABLE 1 Physical property tests of inventive
formulation as applied to a dental dressing. Shear Dentin
Compressive Flexural Bond Dental Hardness Strength DTS Strength
Strength Material (KHN) (MPa) (MPa) (MPa) (MPa) Inventive 36.6
(3.3) 162.9 (19.2) 27.67 (2.3) 82.1 12.2 formulation (5.3) (4.2)
FUJI IX .TM. 51.9 (2.3) 167.8 (29.4) 18.8 (3.8) 18.2 6.0 GP (3.2)
(2.0) IRM .RTM. 11.4 (1.6) 57.8 (10.9) 7.9 (0.9) 15.9 Not (1.7)
tested KETAC- 45.1 (9.4) 149.1 (40.8) 24.8 (4.3) 17.3 3.9 MOLAR
.TM. (6.7) (1.2)
[0044] The inventive formulation proved to have properties that
were comparable or better than those of the materials tested.
Placement of the inventive formulation on teeth requires minimal
surface preparation and fewer steps for application, such as acid
etching, priming, or use of bonding agents, resulting in less
clinical time. In addition, the inventive formulation releases
fluoride. Table 2 presents the results of fluoride-release
tests.
TABLE-US-00006 TABLE 2 Cumulative fluoride release after 385 hours.
Dental Material Fluoride (ppm) Inventive Formulation 159.10 FUJI IX
.TM. GP 176.05 Ketac-Bond 201.29 IRM .RTM. 0
Method of Use as Luting Cement for Bonding Fixed Dental Prosthetic
Devices:
[0045] The inventive formulation may also be used as luting cement,
for bonding fixed dental prosthetic devices, such as inlays,
onlays, laminate veneers, bridges and crowns (including porcelain
and porcelain fused to metal restorations), to dentin and
enamel.
Example 2
Properties as Luting Cement for Bonding Ceramic Dental Prosthetic
Devices
[0046] The preferred formulation of the inventive composition
previously stated was also tested as luting cement for bonding
fixed dental prosthetic devices.
[0047] Shear bond strengths (SBS) of DENTSTAT.TM. (the preferred
inventive formulation) and five commercially available luting
cements to three types of ceramic substrates were determined (Table
3). Ten specimens of each material were tested.
TABLE-US-00007 TABLE 3 Luting cements and ceramic materials used in
this study. Manufacturers Luting cements DENTSTAT .TM. Ultradent
Products, Inc, South Jordan, UT MultiLink Automix Ivoclar/Vivadent,
Schaan, Liechtenstein Aegis C&B BOSWORTH .RTM. Co., Skokie, IL
PANAVIA 21 .RTM. Kuraray America Inc, New York, NY Maxcem Kerr Co,
Orange, CA NX3 Kerr Co, Orange, CA Ceramic materials IPS Empress
CAD Ivoclar/Vivadent, Schaan, Liechtenstein Vitablocs Mark III
Vident, Brea, CA Paradigm C 3M .TM./ESPE Corporation, St. Paul,
MN
[0048] Ceramic blocks provided by the manufacturers were used
without mechanical modification. All ceramic surfaces were treated
using porcelain etching gel (Pulpdent Co. Watertown, Mass.) and
silanated following the manufacturers' instructions.
[0049] A #4 gelatin capsule (Torpac, Inc., Fairfield, N.J.) was
half-filled with a resin composite (P60, 3M.TM. ESPE, St. Paul,
Minn.) and light activated for 40 seconds using a curing light
(Spectrum 800, Dentsply/Caulk, Milford, Del.). The remainder of the
capsule was filled with the dental luting cement being tested,
placed against the ceramic test surface, and stabilized with finger
pressure. Excess material was removed from the base of the capsule,
and the luting cement was allowed to set at room temperature
(23.+-.1.degree. C.) for 10 minutes. The specimens were stored in
37.+-.1.degree. C. deionized water for 24 hours.
[0050] The specimens were tested to failure in shear with a testing
machine (MTS, Alliance RT/5, MTS Corporation, Eden Prairie, Minn.)
using a crosshead speed of 0.5 mm/min. Mean shear bond strengths
(SBS) and standard deviations were calculated, and means were
analyzed statistically using one-way ANOVA and Tukey's Test. The
mode of failure was determined for each specimen by visual
examination.
[0051] The results are presented in the Table 4. Failures occurred
all within the ceramic materials. The mean SBS for DENTSTAT.TM. was
not significantly higher than the SBS for MultiLink Automix when
bonding to IPS Empress CAD and Paradigm C. However, the SBS of
DENTSTAT.TM. was significantly higher than other luting cements
when bonding to Vitablocs Mark III. Therefore, the SBS of
DENTSTAT.TM. to all three ceramic substrates were comparable to or
greater than the other luting cements tested.
TABLE-US-00008 TABLE 4 Shear bond strength, means (st. dev.), MPa,
n = 10. The SBS of materials with the same letter within a column
are not significantly different (p > 0.05) IPS Vitablocs Empress
CAD Mark III Paradigm C DENTSTAT .TM. 25.3 (3.72) A 20.2 (4.59) A
22.2 (3.90) A MultiLink 21.5 (4.98) A 11.8 (3.76) B 18.8 (4.34) A,
B Automix Aegis C&B 12.8 (2.88) B, C 12.7 (2.35) B 14.2 (3.01)
B, C PANAVIA 21 .RTM. 12.3 (2.18) B, C 13.0 (2.80) B 14.0 (4.12) B,
C Maxcem 12.5 (4.21) B, C 11.6 (2.79) B 13.2 (3.50) C NX3 12.0
(1.99) B, C 12.4 (4.28) B 12.1 (2.68) C
Example 3
Properties as Luting Cement for bonding Fixed Metal Dental
Prosthetic Devices
[0052] The shear bond strengths (SBS) of DENTSTAT.TM. and five
commercially available luting cements to three metal substrates
were determined (Table 5). Metal alloy specimens (approximately 8
mm long, 8 mm wide and 4 mm thick) were fabricated per
manufacturers' instructions using the lost wax technique. The metal
specimens were mounted in autopolymerizing acrylic resin using
cylindrical polytetrafluoroethylene molds with the test surface of
the specimens flush with the surface of the acrylic. The test
surfaces were sandblasted.
TABLE-US-00009 TABLE 5 Luting cements and metal alloys used in this
study. Manufacturers Luting cements DENTSTAT .TM. Ultradent
Products, Inc, South Jordan, UT PANAVIA 21 .RTM. Kuraray Medical
Inc., New York, NY GC Fuji Plus GC America, Inc, Alsip, IL KETAC
CEM .TM. 3M/ESPE Corporation, St. Paul, MN ACP C&B Harry J.
Bosworth, Skokie, IL Durelon 3M/ESPE Corporation, St. Paul, MN
Metal alloys FIRMILAY .RTM. Jelenko, San Diego, CA REX4 .TM.
Pentron Alloys, LLC, San Diego, CA OLYMPIA .RTM. Jelenko, San
Diego, CA
[0053] A #4 gelatin capsule (Torpac, Inc., Fairfield, N.J.) was
half-filled with a resin composite (P60, 3M.TM./ESPE Corporation,
St. Paul, Minn.) and light activated for 20 seconds using a curing
light (Spectrum 800, Dentsply/Caulk, Milford, Del.). The remainder
of the capsule was filled with the dental luting cement being
tested, placed against the metal test surface, and stabilized with
finger pressure. Excess material was removed from around the base
of the capsule, and the luting cement was allowed to set at room
temperature (23.+-.1.degree. C.) for 10 minutes. The specimens were
stored in 37.+-.1.degree. C. deionized water for 24 hours before
testing.
[0054] The specimens were tested to failure in shear with a testing
machine (MTS, Alliance RT/5, MTS Corporation, Eden Prairie, Minn.)
using a crosshead speed of 0.5 mm/min. Mean shear bond strengths
(SBS) and standard deviations were calculated, and means were
analyzed statistically using one-way ANOVA and Tukey's Test. The
results are presented in the Table 6. The shear bond strengths of
DENTSTAT.TM. to REX4.TM. and OLYMPIA.RTM. were comparable to or
greater than those of the other products. Its bond strength to
Firmilay was comparable to those of three other cements.
TABLE-US-00010 TABLE 6 Shear bond strength means and standard
deviations, (MPa), n = 10. Firmilay .RTM. Rex4 .TM. Olympia .RTM.
DentStat .TM. 4.0 (0.75) C, D 15.0 (3.65) A 12.9 (1.33) A Panavia
21 .RTM. 9.4 (2.70) A 13.2 (2.60) A 12.5 (1.63) A GC Fuji Plus 6.7
(1.91) B 14.6 (2.17) A 13.3 (2.00) A Ketac Cem .TM. 4.7 (1.87) B, C
5.9 (2.13) B 5.6 (2.10) B ACP C&B 9.1 (0.94) A 7.3 (0.45) B 7.5
(0.40) B Durelon 5.5 (1.50) B, C 4.9 (1.13) B, C 5.7 (1.20) B
ZnPO.sub.4 2.1 (0.68) D 2.8 (0.51) C 2.6 (0.41) C The SBS of the
materials with the same letter within a column are not
significantly different (p > 0.05)
Method of Use as Luting Cement for Bonding Orthodontic Brackets to
Enamel:
[0055] The inventive formulation may also be used as a luting
cement for bonding orthodontic brackets to enamel.
Example 8
Inventive Formulation Used as a Luting Cement for Bonding
Orthodontic Brackets to Enamel
[0056] The shear bond strengths (SBS) to tooth enamel of
DENTSTAT.TM. and five commercially available orthodontic luting
cements were determined. Each brand (Table 7) was designated as an
experimental group with ten specimens in each group.
TABLE-US-00011 TABLE 7 Orthodontic luting cements used in this
study. Luting cements Manufacturers DENTSTAT .TM. Ultradent
Products, Inc, South Jordan, UT Transbond XT 3M/Unitek Monrovia, CA
Heliosit Ivoclar/Vivadent, Schaan, Liechtenstein Aegis Ortho
BOSWORTH .RTM. Co., Skokie, IL GC Fuji LC GC America Inc, Alsip, IL
Ortho Choice Pulpdent Co. Watertown, MA
[0057] Sixty extracted, noncarious human molar teeth were used for
the bond strength test. Surface debris was manually removed from
the teeth, and the teeth were stored in a 0.5 percent aqueous
solution of Chloramine-T (Sigma-Aldrich, St. Louis, Mo. 63178)
prior to specimen preparation. During specimen fabrication, the
enamel surfaces of the teeth were treated following manufacturers'
instructions for luting orthodontic brackets. An orthodontic
bracket (SYNERGY.RTM., RMO.RTM. Roth straight wire, Rocky Mountain
Orthodontics, Denver, Colo.) was positioned on the prepared enamel
surface with one of the luting cements and photo-cured for 40
seconds (ten seconds on each side of the bracket) using a dental
curing light (Spectrum 800, Dentsply/Caulk). The specimens were
stored in 37.+-.1.degree. C. deionized water for 24 hours before
testing.
[0058] The specimens were tested to failure in shear with a testing
machine (MTS, Alliance RT/5) using a crosshead speed of 0.5 mm/min.
Following shear bond strength testing, all specimens were examined
at 8.times. magnification using a stereomicroscope to determine the
mode of failure between the luting cement and enamel. Mean SBS and
standard deviations were calculated, and means were analyzed
statistically using one-way ANOVA and Tukey's Test.
[0059] The results are presented in the Table 8. The shear bond
strength of DENTSTAT.TM. to enamel was significantly higher than
those of the other luting cements. All failures were at the
cement/enamel interface.
TABLE-US-00012 TABLE 8 Shear bond strength to enamel, means (st
dev), n = 10. SBS (MPa) DentStat .TM. 12.7 (2.13) A Transbond XT
11.8 (2.25) B Heliosit 10.7 (2.88) B Aegis Ortho 10.6 (1.72) B GC
Fugi LC 9.59 (1.21) B Ortho Choice 9.39 (1.29) B Materials with the
same letter are not significantly different (p > 0.05).
[0060] Because its superior mechanical properties, the inventive
composition may be used in many other dental or biomedical
applications, such as stint for stabilizing avulsed, inverted, or
luxated teeth, or as bone cement, for bonding implant prostheses
and skull implants to bone, or liner and base under amalgam dental
restorations.
[0061] Obviously, many modifications and variations of the present
invention are possible in light of the above teaching. It is
therefore to be understood that, within the scope of the appended
claims, the invention may be practiced otherwise than as
specifically described. The principles described above can be
readily modified or adapted for various applications without
departing from the generic concept, and therefore such adaptations
and modifications are intended to be comprehended within the
meaning and range of equivalents of the enclosed embodiments. It is
to be understood that the terminology and phraseology herein is for
the purpose of description and not of limitation.
* * * * *