UNIVERSIDADE ESTADUAL PAULISTA
“JÚLIO DE MESQUITA FILHO”
Instituto de Ciência e Tecnologia
Campus de São José dos Campos
ORIGINAL ARTICLE DOI: https://doi.org/10.4322/bds.2024.e4406
1
Braz Dent Sci 2024 Oct/Dec;27 (4): e4406
This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in
any medium, provided the original work is properly cited.
Bond strength of a three-step adhesive system modified by
beta- TCP particles
Avaliação da resistência de união de um sistema adesivo convencional de três etapas modificado por partículas BETA-TCP
Lucas Rodarte Abreu ARAÚJO1 , Stéphanny Maria MEIRA1 , Monica YAMAUTI2 , Erisandra Rodrigues Alves LOURENÇO3 ,
Ricardo Emílio Ferreira Quevedo NOGUEIRA3 , Alberto Nogueira da Gama ANTUNES1
1 - Pontifícia Universidade Católica de Minas Gerais, Departamento de Odontologia. Belo Horizonte, MG, Brazil.
2 - Universidade Federal de Minas Gerais, Faculdade de Odontologia, Departamento de Odontologia Restauradora. Belo Horizonte, MG, Brazil.
3 - Universidade Federal do Ceará, Departamento de Engenharia Metalúrgica e de Materiais. Fortaleza, CE, Brazil.
How to cite: Araújo LRA, Meira SM, Yamauti M, Lourenço ERA, Nogueira REFQ, Antunes ANG. Bond strength of a three-step adhesive system
modied by beta- TCP particles. Braz Dent Sci. 2024;27(4):e4406. https://doi.org/10.4322/bds.2024.e4406
ABSTRACT
Objective: This study aimed to evaluate the bond strength and fracture pattern of a three-step dentin adhesive system,
Scotch Bond Multipurpose (SBMP) (3M ESPE), with or without beta-tricalcium phosphate (β-TCP) particles added to
the primer solution. Material and Methods: Twelve human molar teeth were used, each sectioned perpendicularly
into dentin discs. These discs were randomly allocated into three groups: G1 (control), G2 (primer modied with
β-TCP 0.5%), and G3 (primer modied with β-TCP 2%). Each group consisted of four discs for testing. The dentin
discs were treated according to the adhesive system protocol. After storage in distilled water, the discs were treated
with 35% phosphoric acid gel, the primer (modied or not), and SBMP adhesive, followed by light-curing (Valo
Ultradent). Twenty-four hours later, each restored dentin disc was sectioned to obtain specimens for tensile strength
testing. Fracture pattern analysis was performed using scanning electron microscopy (SEM). Results: Statistical
analysis of the tensile strength results showed no signicant difference between the control and modied adhesive
systems. The fracture pattern observed using SEM was predominantly mixed. Conclusion: The addition of β-TCP
particles to the adhesive primer solution did not affect bond strength or the fracture pattern.
KEYWORDS
Dentin adhesives; Beta Particles; SEM; Tensile strength; Tooth remineralization.
RESUMO
Objetivo: Este estudo teve como objetivo avaliar a resistência de união e o padrão de fratura de um sistema adesivo
dentinário de três etapas, Scotch Bond Multipurpose (SBMP) (3M ESPE), com ou sem partículas de fosfato de
beta-tricálcio (β-TCP) adicionadas à solução primer. Material e Métodos: Foram utilizados doze dentes molares
humanos, cada um seccionado perpendicularmente em discos de dentina. Esses discos foram aleatoriamente
distribuídos em três grupos: G1 (controle), G2 (primer modicado com β-TCP 0,5%) e G3 (primer modicado
com β-TCP 2%). Cada grupo consistiu de quatro discos para teste. Os discos de dentina foram tratados de
acordo com o protocolo do sistema adesivo. Após armazenamento em água destilada, os discos foram tratados
com gel de ácido fosfórico a 35%, primer (modicado ou não) e adesivo SBMP, seguido de fotopolimerização
(Valo Ultradent). Vinte e quatro horas depois, cada disco restaurado foi seccionado para obter espécimes para
teste de resistência à tração. A análise do padrão de fratura foi realizada utilizando microscopia eletrônica de
varredura (MEV). Resultados: A análise estatística dos resultados de resistência à tração não mostrou diferença
signicativa entre o sistema adesivo controle e os modicados. O padrão de fratura observado por meio da MEV
foi predominantemente misto. Conclusão: A adição de partículas de β-TCP à solução primer adesiva não afetou
a resistência de união nem o padrão de fratura.
PALAVRAS-CHAVE
Adesivos dentinários; Partículas Beta; MEV; Resistência à tracção; Remineralização dentária.
2
Braz Dent Sci 2024 Oct/Dec;27 (4): e4406
Araújo LRA et al.
Evaluation of the bond strength of a three-step conventional adhesive system modified by BETA-TCP particles
Araújo LRA et al. Bond strength of a three-step adhesive system modified by
beta- TCP particles
INTRODUCTION
Composite resins, used in dentistry as
restorative materials, are based on methacrylate
monomers, inorganic ller particles and require
an adhesive system to bond to dental tissues.
Among the factors that can affect adhesive
integrity, the polymerization shrinkage of these
materials, causing microleakage and secondary
caries, are disadvantages that can lead to
restoration failure [1].
The development of composite materials with
antibacterial properties can result in a reduction
of their mechanical properties [2,3]. However,
since antibacterial properties are important,
especially at the interface between the restorative
material and the tooth, it is more effective to
incorporate antibacterial agents into the materials
used as a base for restoration, such as adhesive
systems [4]. Nevertheless, the use of these
antibacterial materials alone does not guarantee
the prevention or treatment of dental caries [5].
Calcium phosphate-based biomaterials
are known for their high biocompatibility [6].
However, the combination of bioactive β-tricalcium
phosphate (β-TCP) particles with water results in
the precipitation of dicalcium phosphate dehydrate.
This process can lead to microinltration, increasing
the risk of dental caries and eventually resulting in
restoration failure [4].
In three-step adhesive systems, dentin tissue
is treated with 35% phosphoric acid to achieve
proper interconnection between the composite
and the tooth structure. This conditioning leaves
a demineralized collagen layer, within which uid
and hydrophilic adhesive systems can penetrate.
However, this penetration occurs with varying
degrees of bonding and sealing. To achieve the
antibacterial action of the adhesives, it would
be benecial for compounds based on calcium
phosphate, for example, to be released, aiding
in the remineralization of dentin tissues when
conditioned [4].
Current adhesive systems are designed
for superior clinical performance in adhesion-
based aesthetic restorations, but they lack
important antibacterial properties. Even
materials that exhibit some antibacterial effects
have not demonstrated the expected clinical
signicance. This is due to the lack of investment
in antimicrobial formulations and the scarce
evidence in the literature regarding their real
benefits in clinical practice, especially in the
prevention of caries recurrence [2].
Remineralization of areas affected by
adhesive conditioning can improve the quality
and longevity of the restorative material-dentin
interface. Thus, developing materials that release
bioactive ions is a goal of dental biomaterials
research [7].
Biocompatibility is a common property of
calcium phosphate-based materials, including
hydroxyapatite, bioactive ceramics, tricalcium
phosphate (α-TCP and β-TCP). The reason for the
biocompatibility of calcium phosphate biomaterials
is that this material is the main inorganic constituent
of hard tissues, and free calcium and phosphorus
ions can be used in metabolism [6].
The current goal in the manufacture of
dental adhesives is to create a durable adhesion
to dentin and protect the collagen brils exposed
after acid action, either alone or using self-etching
adhesives. The incorporation of minerals into
this demineralized dentin is interesting because
the mineral can act to reduce degradation at the
adhesive interface [8].
Studies have shown that various particles have
been incorporated into adhesive systems, aiming to
promote ionic exchange and mineral precipitation
with the hybrid layer. These particles include
bioactive glasses, Portland cement, and calcium
phosphate [9,10] however, the incorporation
of these minerals can significantly reduce the
mechanical properties of these composites [7].
The growing interest in minimally invasive
treatments has led to the development of modalities
that minimize the removal of dentin tissue. For
these interventions, restorative materials with
antibacterial properties would be highly benecial
and would aid in the remineralization process of
these affected dentin tissues. Therefore, the aim of
this study was to evaluate the bond strength and
fracture pattern of a three-step dental adhesive,
with or without the addition of β-TCP particles in
the system’s primer solution.
MATERIAL AND METHODS
For this study, 12 caries-free and/or restora-
tion-free human molars were used, which were
extracted for orthodontic, surgical, or periodontal
reasons. After removal, they were cleaned and
stored at 0°C.
3
Braz Dent Sci 2024 Oct/Dec;27 (4): e4406
Araújo LRA et al.
Evaluation of the bond strength of a three-step conventional adhesive system modified by BETA-TCP particles
Araújo LRA et al. Bond strength of a three-step adhesive system modified by
beta- TCP particles
The study was carried out in accordance
with all the criteria of the Ethics Committee
of the Pontifical Catholic University of Minas
Gerais (PUC Minas) and approved under number
60187016.0.0000.5137.
Experimental groups, application of adhe-
sives, and production of restorations
Four teeth were used for each experimental
condition, as follows: G1, Scotchbond adhesive
system primer without modification (control
group); G2, Scotchbond multipurpose adhesive
system primer (3M ESPE) modied with 0.5% by
weight of β-TCP; and G3, primer modied with
2% by weight of β-TCP.
Before the adhesion and restoration procedure
was performed with a composite resin, each tooth
was xed onto a lightly heated acrylic plate. The
teeth attached to the plate were sectioned in a
precision cutting machine (Isomet 100, Buehler
Ltd., Lake bluuff, IL, USA) equipped with a
diamond impregnated disc (15LC Series Diamond,
Isomet Buehler-Microstructural Analysis Division,
Lake Bluff, Illinois, 60044-USA) with abundant
irrigation and a rotational speed programmed to
300 rpm. Two perpendicular cuts along the long
axis of the tooth were produced. The rst cut
removed the occlusal portion and the second cut
removed the roots of the teeth, approximately 2
mm above the cementoenamel junction. The nal
result was dentin discs approximately 4 mm thick
with enamel on the edges. The pulp chamber area
was lled with Scotchbond Multipurpose adhesive
and Z100 composite resin (3M ESPE) (Table I),
was adapted to close the hole in the pulp region in
all discs and subsequently stored in distilled water.
After the rst described step, each adhesive
from each experimental condition was applied to
the dentin surface according to the procedures
described in Table I. The photopolymerization
of the adhesive systems was carried out using
a light-curing device (Valo, Ultradent) with an
intensity of 1,400 mW/cm2, as reported by the
manufacturer. The increments of composite resin
(Z100, Color A3, 3M ESPE) were applied directly
onto the surface of the restored tooth, being light-
cured for 20 seconds each, so that the nal result
was dentin discs restored with composite resin.
Production of test specimens
After applying the adhesives and preparing
the composite resin restoration, all disks were
stored in distilled water for 24 hours. Each
restored dentin disc was attached to an acrylic
base using a heated blade and secured to a
precision cutter equipped with a diamond disc. A
series of perpendicular cuts along the tooth axis
in the distal-mesial direction were made under
abundant water irrigation. The dentin and resin
plates were then removed from the acrylic base
and repositioned one by one with sticky wax to
make cuts perpendicular to the initial cuts. Thus,
specimens with the geometric shape of a toothpick
and a cross-sectional area of 0.8±0.4 mm2 were
produced. Sticks from the peripheral region were
discarded. Approximately 10 to 15 toothpicks were
obtained from each restored dentin disc. All sticks
produced from each disc were stored in distilled
water at 37°C for 24 hours [11].
Tensile test
For each disc, ve toothpicks were randomly
selected to evaluate tensile strength. For the
execution of the tensile test, each toothpick
was attached to the Geraldelli device with
cyanoacrylate based glue. This device was then
coupled to a universal test machine (Bisco,
Schaumburg, IL, USA) with a 500N load cell
(Static Load Cell, Instron, Norwood, MA, USA).
The tensile test was conducted at a velocity
of 0.5 mm/min until total specimen rupture,
obtaining union strength values in Newtons (N).
The conversion of the values into megapascals
(MPa) was performed after measuring the
cross-sectional area of the specimens using an
electronic digital caliper (Vonder PDV 1500, O.V.D
Table I - Composition and mode of application in dentin of the
three-step adhesive system Scotchbond Multipurpose
Composition Method of
application (dentin)
Primer
2-hydroxyethyl methacrylate
(HEMA) polycarboxylic acid
and water.
Adhesive
2-hydroxyethyl methacrylate
(HEMA), Bis-GMA and
photoactivators.
1. Conditioning with 35%
phosphoric acid for 15 seconds;
2. Rinse for 15 seconds;
3. Dry for 5 seconds;
4. Preparation: apply the
primer to the conditioned
enamel and dentin and dry
gently for 5 seconds;
5. Adhesive application: apply
the adhesive to prepared
dentin and enamel;
6. Light cure for 10 seconds.
4
Braz Dent Sci 2024 Oct/Dec;27 (4): e4406
Araújo LRA et al.
Evaluation of the bond strength of a three-step conventional adhesive system modified by BETA-TCP particles
Araújo LRA et al. Bond strength of a three-step adhesive system modified by
beta- TCP particles
Importadora e Distribuidora LTDA, Curitiba, PR,
Brazil), according to the following formula:
( )
²
Resistance value in Newtons N MPa
Specimen area in mm
= (1)
Each experimental condition consisted of 20
toothpicks, originating from the four discs (each
disc supplied ve toothpicks). Thus, the number
of samples (n) in the present study was 20.
Fracture pattern
The specimens with the highest and lowest
resistance values of each disc were considered
for evaluation of the fracture pattern. Thus, eight
specimens from each experimental condition
were evaluated: four discs for each condition,
and two sticks with the highest and lowest MPa
values were removed. To facilitate classication,
the two fractured sides of the composite resin and
dentin were xed in double-sided carbon tape
stubs and dehydrated for 2 hours inside a silica
gel- containing container. The specimens were
then covered in gold using a metallizer (Denton
Vacuum, DESK V, Standard model, JEOL, USA)
and were observed using a scanning electron
microscope (SEM; JEOL, JSM - IT 300, USA) with
an acceleration of 30 KV, WD of 14 mm, spotsize
of 55 nm, and a high vacuum.
Each selected test body was classified
according to the following denominations:
Type I, adhesive failure at the base of the
hybrid layer; Type II, cohesive failure in dentin;
Type III, cohesive failure in the hybrid layer;
Type IV, cohesive failure in the adhesive layer; and
Type V, cohesive failure in the composite resin.
Production of primer solutions
Two solutions of experimental primer were
produced. The primer base solution was that
of the three-step adhesive system, Scotchbond
Multipurpose. For each solution, 1 ml was
extracted from the primer vial and placed in a 1.5
ml Eppendorff ask. We followed the previous
recommendations of Mehdikhani and Borhani to
synthesize β-TCP nanoparticles. In brief, calcium
nitrate tetrahydrate ((Ca(NO3)2·4H2O) (98%,
Merck, Kenilworth, NJ, USA) and diammonium
hydrogen phosphate ((NH4)2HPO4) (99%,
Merck) were reacted to produce β-TCP
nanoparticles. Initially, a white precipitate was
formed by adding 500 mL of 0.6 mol Ca(NO3)2
(pH = 7.3) dropwise over 2–3 hours into
500 mL of 0.4 mol (NH4)2HPO4 solution (pH =
4) that was vigorously stirred beforehand. During
this reaction, aliquots of 0.1 M sodium hydroxide
(99%, Merck) were used to maintain the pH
of the system. The resultant white precipitate
was stirred for 12 hours and then washed with
distilled water (DW) and ethanol to enhance its
dispersion properties. Using gentle suction, this
mixture was ltered through a lter glass. The
ltration cake was dried at 80°C for one day.
The next day, the dried powders were ground
using a mortar and pestle and calcined in an
alumina crucible at 700°C for 2 hours [11]. These
solutions, as well as the original primer solution
(control) were used to prepare the conditioned
dentin with phosphoric acid.
The results obtained in the tensile tests from
different groups were evaluated statistically:
normality test D’agostino and Pearson, Analysis
of variance (ANOVA) and Tukey test with level
of significance 95%. The analysis of variance
(ANOVA) will compare the bond strength of an
adhesive system modied with the addition of
β-TCP particles at concentrations of 0,5% and
2,0% to the unmodified adhesive system. It
will evaluate whether the observed differences
between the sample means are statistically
signicant, using the F-test to determine if the
effect of the additives is signicant compared to
the system without any β-TCP particle addition.
RESULTS
Tensile test
There was no statistically significant
difference between the groups in the traction
test after 24 hours or storage time. Results of
data analyzed by ANOVA (Table II and Graph 1).
Fracture pattern
The fracture pattern in analyzed specimens
was predominantly mixed, representing adhesive
and cohesive failure.
Table II - Mean values of standard deviation obtained through the
tensile tests in megapascals
Adhesive 24 Hours
SMBP control 35.37 (12.54) A
SBMP + 0.5% β-TCP 30.50 (9.53) A
SBMP + 2% β-TCP 28.51 (11.86) A
SBMP, Scotchbond Multipurpose; β-TCP, beta-tricalcium phosphate;
A, there is no statistical difference.
5
Braz Dent Sci 2024 Oct/Dec;27 (4): e4406
Araújo LRA et al.
Evaluation of the bond strength of a three-step conventional adhesive system modified by BETA-TCP particles
Araújo LRA et al. Bond strength of a three-step adhesive system modified by
beta- TCP particles
SEM analysis of each body showed that
cohesive failure was predominant in relation
to adhesive failure, varying between cohesive
defects in the dentin, cohesive in the hybrid layer,
cohesive in the adhesive layer, and cohesive in
the composite resin (Figures 1, 2 and 3).
The SEM images showed that the majority
of specimens had mixed fracture patterns, and
adhesive defects could be observed at the base of
the hybrid layer in the presence of cohesive faults,
which are located in the dentin, hybrid layer,
adhesive, and composite resin (Figures 2).
Only a purely adhesive failure was found
in a fractured specimen in the control group.
Graph 1 - Mean values and standard deviation obtained through
the tensile tests in megapascals.
Figure 1 - SEM images of the Scotch Bond Multipurpose adhesive system, showing mixed fracture patterns. Two homologous bodies were
observed after the fracture in smaller and larger increase, in the left and right columns (dentin side). CR, composite resin; hl, hybrid layer;
Bhl, base of the hybrid layer; ad, sticker. The semi-transparent blue box in the image (A) represents the largest increase shown in (C). The
semitransparent red image box (B) represents the increase shown in (D).
The other samples presented mixed patterns
(Graph 2).
DISCUSSION
Ensuring the longevity of adhesive restorative
procedures means that efforts were made to
stabilize the dentin region after acid etching
and exposure of collagen fibers. The concept
of remineralization based on the interaction of
bioactive ions was recently developed [12] and the
central objective would shield the demineralized
collagen layer [13] after using phosphoric acid on
dentin. There should be no damage or a decrease
in the region of the union. The incorporation
of bioactive inorganic fillers can enhance the
mechanical properties of dentin adhesives. The
presence of essential remineralization sources,
such as calcium and phosphate, ensures that the
dentin adhesive can remineralize the adhesive-
dentin interface [14,15].
The present study conrmed that β-TCP at
concentrations of 0.5% and 2% did not cause a
decrease in bond strength values with dentin.
The presence of these two ion sources ensures
the remineralization of the adhesive-dentin
junction, extending the lifespan of the composite
restoration [11,16].
6
Braz Dent Sci 2024 Oct/Dec;27 (4): e4406
Araújo LRA et al.
Evaluation of the bond strength of a three-step conventional adhesive system modified by BETA-TCP particles
Araújo LRA et al. Bond strength of a three-step adhesive system modified by
beta- TCP particles
Figure 2 - SEM images of the Scotch Bond Multipurpose adhesive system, modified with 0,5% β-TCP by weight, showing a mixed fracture
pattern. CR, composite resin; hl, hybrid layer; Bhl, base of the hybrid layer; ad, sticker. The semi-transparent blue box in the image (A) represents
the largest increase shown in (C). The semitransparent red image box (B) represents the increase shown in (D). The image (E) represents the
magnification of image (C) and the image (F) represents the magnification of image (D) (x500 increase).
Figure 3 - SEM image of the Scotch Bond Multipurpose adhesive system, modified with 2% β-TCP by weight, showing a mixed fracture pattern.
7
Braz Dent Sci 2024 Oct/Dec;27 (4): e4406
Araújo LRA et al.
Evaluation of the bond strength of a three-step conventional adhesive system modified by BETA-TCP particles
Araújo LRA et al. Bond strength of a three-step adhesive system modified by
beta- TCP particles
The justication for using these concentra-
tions of β-TCP (0.5% and 2%) is that this com-
ponent must dissolve in the primer solutions of
the adhesive systems. When β-TCP is added in
concentrations greater than 2% by weight, the
solutions become very viscous, often making
it impossible to fully dissolve the β-TCP. This
prevents the correct execution of adhesive proce-
dures according to the manufacturer’s recommen-
dations. A previous study suggested that when
incorporating inorganic llers into adhesives, the
weight concentration should not exceed 10%,
as this may compromise bond strength due to a
signicant increase in viscosity [17,18].
In an in vitro study, adhesives capable of
releasing uoride ions were tested to evaluate the
deposition of crystals in gaps between restorative
materials and dental tissues (enamel and dentin).
Positive results were observed over the storage
period, suggesting that such adhesives could repair
aws resulting from these procedures [19,20].
Other studies that have sought modications
in adhesive systems to make them bactericidal
and induce remineralization include Bapna et al.
In 1988 and 1992, studies have been conducted
to evaluate the antibacterial properties of Scotch
Bond adhesive and other adhesive systems, as
well as to assess bond strength [21-23]; other
authors have tried to introduce antibiotics and
bactericidal agents into the adhesive or primer
systems with good results from the biological and
mechanical points of view [24].
Since, adhesion in various parts of the
tooth can be inuenced by different functional
monomers, methacrylates, solvents, the pH of
adhesive systems, in addition to the thickness of
the dentin [25].
Since then, new strategies have been used
to reduce degradation in adhesive restorations.
The current strategy to reduce degradation
at the adhesive interface is called biomimetic
remineralization [26] and it consists of inducing
the formation of apatite crystals in the exposed
collagen regions and in the internal spaces of
the adhesive layer [27]. This process intends to
imitate the natural process of remineralization by
lling the collagen of the demineralized dentin in
the interbrilar and intrabrillary regions [28].
The biomimetic remineralization process
is modulated by non-collagenous analogues of
dentin phosphoproteins [12,28,29]. They are
responsible for maintaining the calcium phosphate
present in the nanometer-sized dentin, sufcient to
penetrate the demineralized collagen brils [12].
Bioactive Portland cement (calcium silicate)
is the most widely used substance for biomimetic
remineralization, with promising laboratory results
regarding remineralization of dentin and union
interface [30,31]. However, when its dissolution
occurs, there is formation of spaces that are lled
by water, leading to degradation [31]. Another
alternative, which was used in the present study, is
using materials based on β-TCP, which may induce
the formation of new hydroxyapatite crystals [4].
The use of calcium phosphate-based
compounds when combined with water leads
to the precipitation reaction of another calcium
phosphate-based product, dicalcium phosphate
Graph 2 - Evaluation of fracture patterns obtained using scanning electron microscopy (SEM). All fracture patterns were present on the analyzed
discs, and the predominant fracture pattern was type V. Type I, adhesive at the base of the hybrid layer; Type II, cohesive failure in dentin; Type
III, cohesive failure in the hybrid layer; Type IV, cohesive failure in the adhesive; Type V, cohesive failure in the composite resin.
8
Braz Dent Sci 2024 Oct/Dec;27 (4): e4406
Araújo LRA et al.
Evaluation of the bond strength of a three-step conventional adhesive system modified by BETA-TCP particles
Araújo LRA et al. Bond strength of a three-step adhesive system modified by
beta- TCP particles
dihydrate [32]. Dentin adhesives when applied
close to the dental pulp can lead to severe pulpal
inammation [33], while calcium phosphate-
based biomaterials are highly biocompatible [6].
Katoh et al. [34] suggested that the develop-
ment of adhesives containing calcium phosphate
powder as a material for direct pulp capping
could lead to the formation of restorative dentin
on the exposed pulp. The present study shows
that, under our experimental conditions, there
was no mechanical damage associated with
both materials in a formulation that maintains
its mechanical properties associated with β-TCP,
a biomaterial highly that is biocompatible and
capable of acting in the direction of biomimetic
remineralization.
Previous studies have evaluated the relation-
ship between the release of bioactive ions, such
as uoride, and the inuence on the mechanical
properties of these materials, and it can be seen
that those materials with the highest uoride
release had the worst mechanical properties [35].
However, Profeta et al. [31] obtained promising
mechanical effects by adding calcium/sodium
phosphosilicate in the adhesive protocol in com-
posite resin restorations. At different storage
times (24 hours and 6 months), the results of the
tensile tests of the test and control groups were
similar. Furthermore, the authors demonstrated
that bioactive additives of calcium phosphate
particles could increase bond strength through
mineral deposition in the region, acting against
the enzymatic degradation of the hybrid layer.
Other authors also obtained satisfactory
results in mechanical tests using β- TCP. One of
the criteria evaluated by Sauro et al. to include
β-TCP particles in photopolymerizable resins
was the microtraction assay. The results were
positive when incorporating bioactive biomaterial
particles into restorative materials [7,36].
The present study conrmed the nature of
the faults using SEM images. Adhesive failures
that result from material or adhesive procedure
failures were uncommon. This suggests that,
from the mechanical point of view, β-TCP did
not negatively affect the results.
Further studies are needed to conrm the
idea of modifying consolidated adhesive systems
to improve the biological remineralization and
protection capabilities of both the pulp dentin
complex and the adhesive interface.
CONCLUSION
The effects of bonding strength with the
addition of β-TCP particles were investigated in
this study, revealing promising results from a
mechanical perspective. The microtraining tests
showed that adhesive failures, predominantly
adhesion failures, occurred in the experimental
groups that used β-TCP. However, no signicant
statistical differences were observed.
Additional laboratory studies are necessary
to better evaluate the β-TCP concentrations
proposed in this study, especially over long
storage periods.
Author’s Contributions
LRAA: Methodology and writing – Original
Draft Preparation.SMM: Methodology and
Writing Review & Editing. MY: Methodology.
ERAL: Data Curation . REFQN: Supervision.
ANGA: Project Administration, supervision and
formal Analysis.
Conict of interests
The authors of this manuscript certify that
there is no nancial or personal interest of any
nature or type in any product, service and/or
business that is presented in this article.
Funding
This study was supported by the Coordenação
de Aperfeiçoamento de Pessoal de NíveL Superior
(CAPES).
Regulatory Statement
This study was conducted according to all
the requirements of the Ethics Committee of the
Pontical Catholic University of Minas Gerais
(PUC Minas) and received approval under
number 60187016.0.0000.5137.
REFERENCES
1. Brunthaler A, König F, Lucas T, Sperr W, Schedle A. Longevity of
direct resin composite restorations in posterior teeth. Clin Oral
Investig. 2003;7(2):63-70. http://doi.org/10.1007/s00784-003-
0206-7. PMid:12768463.
2. Imazato S. Antibacterial properties of resin composites and
dentin bonding systems. Dent Mater. 2003;19(6):449-57. http://
doi.org/10.1016/S0109-5641(02)00102-1. PMid:12837391.
9
Braz Dent Sci 2024 Oct/Dec;27 (4): e4406
Araújo LRA et al.
Evaluation of the bond strength of a three-step conventional adhesive system modified by BETA-TCP particles
Araújo LRA et al. Bond strength of a three-step adhesive system modified by
beta- TCP particles
3. Leung D, Spratt DA, Pratten J, Gulabivala K, Mordan NJ, Young
AM. Chlorhexidine-releasing methacrylate dental composite
materials. Biomaterials. 2005;26(34):7145-53. http://doi.
org/10.1016/j.biomaterials.2005.05.014. PMid:15955557.
4. Mehdawi I, Neel EAA, Valappil SP, Palmer G, Salih V, Pratten
J, et al. Development of remineralizing, antibacterial dental
materials. Acta Biomater. 2009;5(7):2525-39. http://doi.
org/10.1016/j.actbio.2009.03.030. PMid:19410530.
5. Leme AA, Vidal CMP, Hassan LS, Bedran-Russo AK. Potential role
of surface wettability on the long-term stability of dentin bonds
after surface biomodification. J Biomech. 2015;48(10):2067-71.
http://doi.org/10.1016/j.jbiomech.2015.03.016. PMid:25869721.
6. Yuan H, Li Y, de Bruijn JD, de Groot K, Zhang X. Tissue
responses of calcium phosphate cement: a study in dogs.
Biomaterials. 2000;21(12):1283-90. http://doi.org/10.1016/
S0142-9612(00)00016-8. PMid:10811310.
7. Sauro S, Osorio R, Osorio E, Watson TF, Toledano M. Novel light-
curable materials containing experimental bioactive micro-fillers
remineralise mineral- depleted bonded-dentine interfaces. J
Biomater Sci Polym Ed. 2013;24(8):940-56. http://doi.org/10.1
080/09205063.2012.727377. PMid:23647250.
8. Liu Y, Li N, Qi Y, Dai L, Bryan TE, Mao J, et al. Intrafibrillar
collagen mineralization produced by biomimetic hierarchical
nanoapatite assembly. Adv Mater. 2011;23(8):975-80. http://
doi.org/10.1002/adma.201003882. PMid:21341310.
9. Osorio R, Yamauti M, Sauro S, Watson TF, Toledano M.
Experimental resin cements containing bioactive fillers reduce
matrix metalloproteinase-mediated dentin collagen degradation.
J Endod. 2012;38(9):1227-32. http://doi.org/10.1016/j.
joen.2012.05.011. PMid:22892740.
10. Mehdikhani BBG, Borhani GH. Densification and mechanical
behavior of β-tricalcium phosphate bioceramics. Int Lett Chem
Phys Astron. 2014;36:37-49. http://doi.org/10.56431/p-e9cl64.
11. Desai H, Stewart CA, Finer Y. Minimally invasive therapies for
the management of dental caries-a literature review. Dent
J (Basel). 2021;9(12):147. http://doi.org/10.3390/dj9120147.
PMid:34940044.
12. Tay FR, Pashley DH. Guided tissue remineralisation of partially
demineralised human dentine. Biomaterials. 2008;29(8):1127-
37. http://doi.org/10.1016/j.biomaterials.2007.11.001.
PMid:18022228.
13. He G, Gajjeraman S, Schultz D, Cookson D, Qin C, Butler
WT,etal. NIH Public Access. Motor Control. 2005;27:590-609.
14. Farooq I, Ali S, Al-Saleh S, AlHamdan E, AlRefeai M, Abduljabbar
T, et al. Synergistic effect of bioactive inorganic fillers
in enhancing properties of dentin adhesives: a review.
Polymers (Basel). 2021;13(13):2169. http://doi.org/10.3390/
polym13132169. PMid:34209016.
15. Al-Hamdan RS, Almutairi B, Kattan HF, Alsuwailem NA, Farooq
I, Vohra F, et al. Influence of hy-droxyapatite nanospheres in
dentin adhesive on the dentin bond integrity and degree of
conversion: a Scanning Electron Microscopy (SEM), Raman,
Fourier Transform-Infrared (FTIR), and Microtensile Study.
Polymers (Basel). 2020;12(12):2948. http://doi.org/10.3390/
polym12122948. PMid:33321699.
16. AlFawaz YF, Almutairi B, Kattan HF, Zafar MS, Farooq I, Naseem
M, et al. Dentin bond integrity of hydroxyapatite containing
resin adhesive enhanced with graphene oxide nano-particles-An
SEM, EDX, Mi-cro-Raman, and microtensile bond strength study.
Polymers (Basel). 2020;12(12):2978. http://doi.org/10.3390/
polym12122978. PMid:33327410.
17. Perdigão J. Current perspectives on dental adhesion: (1) Dentin
adhesion – not there yet. Jpn Dent Sci Rev. 2020;56(1):190-207.
http://doi.org/10.1016/j.jdsr.2020.08.004. PMid:34188727.
18. Wagner A, Belli R, Stötzel C, Hilpert A, Müller FA, Lohbauer U.
Biomimetically- and hydrothermally-grown HAp nanoparticles
as reinforcing fillers for dental adhesives. J Adhes Dent.
2013;15(5):413-22. PMid:23560259.
19. Hashimoto M, Nakamura K, Kaga M, Yawaka Y. Crystal growth
by fluoridated adhesive resins. Dent Mater. 2008;24(4):457-63.
http://doi.org/10.1016/j.dental.2007.04.014. PMid:17673282.
20. Braga RR. Calcium phosphates as ion releasing fillers in
restorative resin-based materials. Dent Mater. 2019;35(1):3-14.
http://doi.org/10.1016/j.dental.2018.08.288. PMid:30139530.
21. Bapna MS, Murphy R, Mukherjee S. Inhibition of bacterial
colonization by antimicrobial agents incorporated into
dental resins. J Oral Rehabil. 1988;15(5):405-11. http://doi.
org/10.1111/j.1365-2842.1988.tb00176.x. PMid:3072391.
22. Bapna MS, Mukherjee S, Murphy R. The antimicrobial effect of
an iron-binding agent on Streptococcus mutans. J Oral Rehabil.
1992 Mar;19(2):111-3. http://doi.org/10.1111/j.1365-2842.1992.
tb01087.x. PMid: 1517871.
23. AlRefeai MH, AlHamdan EM, Al-Saleh S, Alqahtani AS, Al-Rifaiy
MQ, Alshiddi IF,etal. Application of β-Tricalcium phosphate in
adhesive dentin bonding. Polymers (Basel). 2021;13(17):2855.
http://doi.org/10.3390/polym13172855. PMid:34502894.
24. Kudou O, Kawashima K, Abe E, Komatsu O. Addition of
antibacterial agents to MMA-TBB dentin bonding systems--
influence on tensile bond strength and antibacterial effect. Dent
Mater J. 2000;19(1):65-74. http://doi.org/10.4012/dmj.19.65.
PMid:11219091.
25. Cevik P, Yildirim AZ, Artvin Z, Ozcan M. Microtensile bond
strength and failure type analysis of self etch adhesive systems
on superficial and deep dentin after long-term water storage.
Braz Dent Sci. 2020;4(4):23. http://doi.org/10.14295/bds.2020.
v23i4.2072.
26. Sauro S, Pashley DH. Strategies to stabilise dentine-bonded
interfaces through remineralising operative approaches – State
of The Art International. Int J Adhes Adhes. 2016;69:39-57.
http://doi.org/10.1016/j.ijadhadh.2016.03.014.
27. Brackett MG, Li N, Brackett WW, Sword RJ, Qi YP, Niu LN,etal.
The critical barrier to progress in dentine bonding with the
etch-and-rinse technique. J Dent. 2011;39(3):238-48. http://
doi.org/10.1016/j.jdent.2010.12.009. PMid:21215788.
28. Cao CY, Mei ML, Li QL, Lo ECM, Chu CH. Methods for biomimetic
remineralization of human dentine: a systematic review. Int J Mol
Sci. 2015;16(3):4615-27. http://doi.org/10.3390/ijms16034615.
PMid:25739078.
29. Niu Z, Pashley B, Mao, Chen T. NIH Public Access. Nano.
2008;6:2166-71.
30. Kim YK, Mai S, Mazzoni A, Liu Y, Tezvergil-Mutluay A, Takahashi
K,etal. Biomimetic remineralization as a progressive dehydration
mechanism of collagen matrices - Implications in the aging of
resin- dentin bonds. Acta Biomater. 2010;6(9):3729-39. http://
doi.org/10.1016/j.actbio.2010.03.021. PMid:20304110.
31. Profeta AC, Mannocci F, Foxton RM, Thompson I, Watson TF,
Sauro S. Bioactive effects of a calcium/sodium phosphosilicate
on the resin-dentine interface: A microtensile bond strength,
scanning electron microscopy, and confocal microscopy study.
Eur J Oral Sci. 2012;120(4):353-62. http://doi.org/10.1111/j.1600-
0722.2012.00974.x. PMid:22813227.
32. Hofmann MP, Young AM, Gbureck U, Nazhat SN, Barralet JE.
FTIR- monitoring of a fast setting brushite bone cement: effect
of intermediate phases. J Mater Chem. 2006;16(31):3199. http://
doi.org/10.1039/b603554j.
33. Costa CA, Mesas AN, Hebling J. Pulp response to direct
capping with an adhesive system. Am J Dent. 2000;13(2):81-7.
PMid:11764832.
10
Braz Dent Sci 2024 Oct/Dec;27 (4): e4406
Bond strength of a three-step adhesive system modified by
beta- TCP particles
Araújo LRA et al.
Evaluation of the bond strength of a three-step conventional adhesive system modified by BETA-TCP particles
Araújo LRA et al. Bond strength of a three-step adhesive system modified by
beta- TCP particles
Date submitted: 2024 June 13
Accept submission: 2024 Nov 12
Alberto Nogueira da Gama Antunes
(Corresponding address)
Pontifícia Universidade Católica de Minas Gerais, Departamento de Odontologia,
Belo Horizonte, MG, Brazil.
Email: antunes1978@gmail.com
34. Katoh Y, Suzuki M, Kato C, Shinkai K, Ogawa M, Yamauchi J.
Observation of calcium phosphate powder mixed with an
adhesive monomer experimentally developed for direct pulp
capping and as a bonding agente. Dent Mater J. 2010;29(1):15-
24. http://doi.org/10.4012/dmj.2009-023. PMid:20379007.
35. Xu X, Burgess JO. Compressive strength, fluoride release
and recharge of fluoride-releasing materials. Biomaterials.
2003;24(14):2451-61. http://doi.org/10.1016/S0142-
9612(02)00638-5. PMid:12695072.
36. Al-Qahtani AS, Tulbah HI, Binhasan M, Shabib S, Al-Aali KA,
Alhamdan MM, et al. Influence of Concentration Levels of
β-Tricalcium Phosphate on the Physical Properties of a Dental
Adhesive. Nanomaterials (Basel). 2022;12(5):853. http://doi.
org/10.3390/nano12050853. PMid:35269344.
