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.e4159
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Braz Dent Sci 2024 Apr/June;27 (2): e4159
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.
Effect of saliva contamination and different decontamination
protocols on microshear bond strength of a universal adhesive to
dentin
Efeito da contaminação por saliva e de diferentes protocolos de descontaminação na resistência de união ao
microcisalhamento de um adesivo universal à dentina
Mohamed Motaz Mohamed EL-SAFTY1 , Khaled Aly NOUR2 , Dena Safwat MUSTAFA2
1 - Badr University in Cairo, Department of Conservative Dentistry. Cairo, Egypt.
2 - Ain Shams University, Department of Operative Dentistry. Cairo, Egypt.
How to cite: El-Safty MMM, Nour KA, Mustafa DS. Effect of saliva contamination and different decontamination protocols on microshear
bond strength of a universal adhesive to dentin. Braz Dent Sci. 2024;27(2):e4159. https://doi.org/10.4322/bds.2024.e4159
ABSTRACT
Objective: To evaluate the effect of saliva contamination and different decontamination protocols on the microshear
bond strength of a universal adhesive to dentin. Material and Methods: 84 bovine teeth were divided into three
groups according to bonding stage at which salivary contamination occurred; before curing of the adhesive, after
curing of the adhesive, and a control group with no salivary contamination. Each group was further subdivided into
four subgroups according to the decontamination protocol used (n=7): no decontamination protocol, rinsing then
reapplication of the adhesive, grinding with sandpaper silicon carbide grit 600 then reapplication of the adhesive
and nally ethanol application then reapplication of the adhesive. Specimens were tested in micro-shear mode.
Results: All the decontamination protocols used in this study to reverse effect of salivary contamination before
curing signicantly improved the bond strength to contaminated dentin (
p
<0.001). Meanwhile, after curing,
ethanol decontamination protocol recorded highest bond strength followed by rinsing and grinding compared to
no decontamination (
p
<0.001). Conclusion: Saliva contamination led to signicant deterioration in the bond
strength regardless of the bonding stage at which saliva contamination occurred. All decontamination protocols
improved the immediate microshear bond strength when contamination occurred before curing of the adhesive,
while ethanol seemed to be the most effective both before curing and after curing.
KEYWORDS
Bond strength; Decontamination; Ethanol; Saliva; Universal adhesives.
RESUMO
Objetivo: Avaliar o efeito da contaminação por saliva e de diferentes protocolos de descontaminação na
resistência de união ao microcisalhamento de um adesivo universal à dentina. Material e Métodos: 84 dentes
bovinos foram divididos em três grupos de acordo com o passo operatório do protocolo adesivo em que ocorreu
a contaminação por saliva: antes da polimerização do adesivo, ou após a polimerização do adesivo e um grupo
controle sem contaminação por saliva. Cada grupo foi subdividido em quatro subgrupos de acordo com o protocolo
de descontaminação utilizado (n=7): sem protocolo de descontaminação; lavagem seguida da reaplicação do
adesivo; lixar a região com lixa de carbeto de silício de granulação 600 e reaplicar o adesivo; aplicar etanol
e reaplicar o adesivo. Os espécimes foram testados no modo de micro-cisalhamento. Resultados: Todos os
protocolos de descontaminação utilizados neste estudo em busca de reverter o efeito da contaminação do adesivo
por saliva melhoraram signicativamente a resistência de união à dentina contaminada (p<0,001). Enquanto
isso, após a polimerização, o protocolo de descontaminação com etanol resultou na maior resistência de união,
seguido pela lavagem, e depois pelo lixamento, em comparação com nenhum protocolo de descontaminação
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El-Safty MMM et al.
Effect of saliva contamination and different decontamination protocols on microshear bond strength of a universal adhesive to dentin
El-Safty MMM et al. Effect of saliva contamination and different decontamination
protocols on microshear bond strength of a universal adhesive
to dentin
INTRODUCTION
Saliva contamination is one of the most
serious challenges facing any dental operator
during restorative procedures. In addition to its
water content, saliva contains macromolecule
proteins and glycoproteins, alongside particles
like calcium, sodium, and aminoacids [1]. Both
constituents of saliva can adversely affect bond
strength. Literature has extensively reviewed
the effect of saliva contamination on adhesive
restorations. The adverse effects of this persistent
clinical challenge includes microleakage at the
tooth-restoration interface with subsequent
postoperative sensitivity, discoloration and
recurrent caries [2].
In light of that, clinicians use all resources
available to ensure proper isolation of the dental
field and simplify the restorative procedure.
Rubber dam placement, as the standard protocol
intended for isolation is successful. However,
its placement can be at times inapplicable, or
difcult like with severely fractured tooth, newly
erupted crowns or with an uncooperative child
or asthmatic patients [3,4].
Additionally, adhesive formulations are
constantly improved to achieve clinically
acceptable bond strengths and simplified
procedures. For that reason, universal adhesives
have become more and more popular [5,6]. Even
with the inevitability of salivary contamination
during multiple restorative procedures, there
is little information on the adverse effects of
saliva contamination on the bond strength
of universal adhesives and how to handle
such a clinical mishap [7-9]. Moreover, no
clear recommendation exists for a clinically
applicable decontamination protocol that takes
into consideration when exactly contamination
has occurred.
Therefore, the aim of this study was to
evaluate the effect of saliva contamination
at different bonding stages and different
decontamination protocols on the immediate
microshear bond strength of a universal adhesive
to dentin. The null hypotheses to be tested was
as follows: the decontamination protocols used
in this study would have no effect on the bond
strength to dentin after saliva contamination
with no difference regarding the bonding stage
at which saliva contamination occurred.
MATERIAL AND METHODS
An adaptation of the CONSORT reporting
guidelines and checklist was used relevant to the
in vitro
setting of the study [10,11].
A research study involving paired sets of
subjects, focusing on a continuous response
variable was conducted. Previous data [12]
showed that the disparity in response within
these matched pairs follows a normal distribution
with a standard deviation of 4.6. In order to
have a 95% probability of correctly rejecting the
null hypothesis, which assumed no difference
between the different decontamination protocols,
given that the actual difference in mean response
was 10.8, sample size was determined to be
5 specimens per group. The signicance level for
this hypothesis test was set at 0.05. To account
for a potential 30% decrease due to pretest
failure, the sample size had been increased to
7 specimens per group. The power analysis
was performed using IBM SPSS Statistics for
Windows, Version 20.0. (Armonk, NY: IBM Corp).
A total of 84 bovine anterior teeth were used
for microshear bond strength testing. In addition
to the comparable histology and structural
changes to human teeth, bovine teeth provide
large sound surfaces [13,14]. The roots were
scraped with a scaler to remove any attached
soft tissue then rinsed under running water.
Teeth were stored in 0.1% thymol solution (El
Gomhouria Company for Trading Chemicals and
Medical Appliances, Cairo, Egypt) at 4 °C for a
maximum period of one month until prepared
(p<0,001). Conclusão: A contaminação por saliva levou a uma deterioração signicativa na resistência de união,
independentemente do passo operatório do protocolo adesivo em que ocorreu a contaminação por saliva. Todos
os protocolos de descontaminação melhoraram a resistência de união ao microcisalhamento imediato quando a
contaminação ocorreu antes da polimerização do adesivo, enquanto o etanol pareceu ser o protocolo mais ecaz
nos dois tipos de contaminação (antes e depois da polimerização).
PALAVRAS-CHAVE
Adesivos universais; Descontaminação; Etanol; Saliva; Resistência ao cisalhamento.
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El-Safty MMM et al.
Effect of saliva contamination and different decontamination protocols on microshear bond strength of a universal adhesive to dentin
El-Safty MMM et al. Effect of saliva contamination and different decontamination
protocols on microshear bond strength of a universal adhesive
to dentin
to avoid dehydration and bacterial growth.
The teeth were thoroughly rinsed under running
water for ve minutes to remove thymol solution
remnants.
The labial surfaces of the teeth were
subjected to mechanical grinding with wet 180-
grit silicon carbide (SiC) (Egyptian Abrasives Co.,
Egypt) paper to create a at dentin surface for
microshear bond strength testing. Then, teeth
were inspected using a magnifying lens (5x)
under good illumination to ensure the absence
of enamel islands within the at dentin surface,
recognized by its distinguishable color. Finally,
roots were cut off using a low-speed, diamond,
abrasive disc (Superdiaex H 365F 190 Horico
Dental, Berlin, Germany) under copious air-
water spray. The pulps were then pulled out
using tweezers (Carl Martin, GmbH, Germany)
and H-les (Mani, Inc, Tochigi, Japan) and pulp
chambers were thoroughly cleaned using distilled
water to remove any remaining pulp tissue.
The pulp chamber of each tooth was lled with
cotton to avoid penetration of the embedding
material into the tooth.
Afterwards, at dentin surfaces were placed
downwards on a clean glass slab and secured
using large double-faced adhesive tape. Polyvinyl
chloride (PVC) rings of ¾ inches in diameter and
2 cm in height were placed around each dentin
slab to serve as molds. Self-cure acrylic resin
(Acrostone, Dent Product, Egypt) was poured to
ll the molds completely embedding each tooth
section. The glass slab was immersed in tap water
to reduce the effect of the exothermic reaction
of acrylic resin during setting. After complete
setting, the double-faced adhesive tape was
removed and each specimen was wet ground on
600-grit silicon carbide paper (SiC) (Egyptian
Abrasives Co., Egypt) for 30 seconds in order
to produce a clinically relevant, uniform smear
layer. Each specimen was then washed with a
three-way syringe for 10 seconds after which the
bonding procedures were immediately carried
out [15].
Specimens were randomly divided out into
three groups according to bonding stage at which
salivary contamination occurred:
Group Cb: saliva contamination before
curing of the adhesive;
Group Ca: saliva contamination after curing
of the adhesive; and
Group C0: control group with no salivary
contamination.
Each group was further subdivided into four
subgroups according to the decontamination
protocol used (n=7):
Group D0: no decontamination protocol
applied;
Group Dr: rinsing for 10s, drying for 5s then
reapplication of the adhesive;
Group Dg: grinding with sandpaper SiC
grit 600 for 10s, then rinsing for 5s and
drying for 5s followed by reapplication of
the adhesive [16,17]; and
Group De: application of ethanol with a
microbrush for 15 seconds then rinsing for 5s
and drying for 5s followed by reapplication
of the adhesive, as shown in Figure 1.
To best simulate natural salivary composition,
fresh unstimulated saliva was collected in a plastic
cup from the principal investigator. The principal
investigator was medically free and did not take
any medication throughout the study. All the
procedures were done in the morning. Oral
hygiene measures (tooth brushing with 1450 ppm
uoridated toothpaste) were done twice per day
(one time in the morning and the other before
sleeping). The procedures were done one hour
after cessation of any salivary stimulation (no
intake of any food, beverage, smoking or chewing
gum, tooth brushing) [18] to ensure less variation
in pH, electrolyte, enzyme and protein levels.
One coat of saliva was applied on the at dentin
surface with a microbrush and left undisturbed
for 10 seconds. Salivary contamination was
performed according to the stage of bonding
whether before curing of the adhesive or after
curing of the adhesive. Each of these groups was
then subjected to one of the decontamination
protocols investigated.
For microshear testing, each specimen
received four polyethylene tubes (0.8 mm
diameter and 1 mm length) positioned over
the uncured adhesive [19] and the All-
Bond Universal adhesive (Bisco, Inc.,
Schaumburg,IL,USA) was light cured for
10 seconds according to the manufacturer’s
instructions. Light curing was performed using
LED light curing unit 3M™
Elipar
™
DeepCure
-S
with an output of 1200 mW/cm2. The owable
resin composite material
Aeliteflo
(Bisco,
Inc., Schaumburg,IL,USA) was injected into
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El-Safty MMM et al.
Effect of saliva contamination and different decontamination protocols on microshear bond strength of a universal adhesive to dentin
El-Safty MMM et al. Effect of saliva contamination and different decontamination
protocols on microshear bond strength of a universal adhesive
to dentin
the polyethylene tube and excess material
was carefully removed. Resin composite was
light cured over the polyester strip. Then, the
polyethylene tube was removed using blade
no.11 (Bard Parker, Xinda Surgical Blades,
Wuxi Xinda Medical Device Co., Ltd., China) by
placing two vertical incisions along the length
of the tube and removing each half separately.
Excess adhesive around each resin composite
cylinder was carefully scraped using the same
blade. Specimens were placed in distilled water
at room temperature for 24 hours until testing.
Samples were labeled to avoid any possible
bias during testing and recording values by the
independent investigator. It is worth noting that
the use of flowable composite ensured fully
compact, well-adapted composite cylinders.
Each specimen containing four resin
composite specimens was tested in shear mode
and the mean for each specimen was calculated.
Shear mode was tested using a wire fixed to
the upper jig of a universal testing machine
(3365 series, Instron, IL, USA). The attachment
was applied as close as possible to the resin/
dentin interface while the specimen was xed
to the lower jig of the testing machine. The load
was applied at a crosshead speed of 0.5mm/min
until failure [20]. At the end, data was collected,
tabulated and transferred to a biostatistician for
analysis.
RESULTS
Results of Two-way ANOVA showed that
bonding stage during which contamination occurs
was found to have a signicant effect (
p
= 0.004)
on immediate microshear bond strength to dentin.
Also, decontamination protocols had a signicant
effect (
p
< 0.001), as well as the interaction
between bonding stage and decontamination
protocol (
p
< 0.001).
A comparison of the simple main effects
presented in Table I and Figures 2 and 3,
showed that saliva contamination signicantly
reduced the bond strength at both bonding
stages compared to the control group C0-D0.
The adhesive recorded its highest bond strength
in the control group (no contamination C0-D0).
There was no signicant difference between the
effect of contamination on the bond strength
values when performed before curing and after
curing of the adhesive (p < 0.001). Alone, all the
decontamination protocols showed a reduction
in the microshear bond strength values for the
no saliva contamination groups compared to
the control group C0-D0. Furthermore, all the
decontamination protocols used in this study to
reverse effect of salivary contamination before
curing signicantly improved the bond strength to
contaminated dentin (CbDr=CbDg=CbDe>CbD0)
(p<0.001). Meanwhile, after curing, ethanol
Figure 1 - Saliva contamination at different bonding stages and decontamination protocols.
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El-Safty MMM et al.
Effect of saliva contamination and different decontamination protocols on microshear bond strength of a universal adhesive to dentin
El-Safty MMM et al. Effect of saliva contamination and different decontamination
protocols on microshear bond strength of a universal adhesive
to dentin
decontamination protocol (CaDe) recorded
highest bond strength followed by rinsing and
grinding (CaDr and CaDg) compared to no
decontamination (CaD0) (p <0.001).
Different superscript small letters indicate a
statistically signicant difference within the same
vertical column, Different superscript capital
letters indicate a statistically signicant difference
within the same horizontal row *significant
(p<0.05).
DISCUSSION
As a general rule for good adhesion, intimate
contact between the adhesive and the adherent is
required [21]. Dentin bonding is considered more
difcult than that of enamel, as the water content
is higher, which can prevent proper wetting by the
hydrophobic dental adhesives [22]. Contaminants
like saliva, blood and gingival uid are still considered
major risk factors that could further negatively
affect the bonding quality to dental substrates [23].
Table I - Comparisons of simple main effects
Decontamination
Protocols
Microshear bond strength (MPa) (Mean±SD)
p-value
C0Cb Ca
D0 19.72±0.68Aa 2.72±0.44Bb 3.79±0.19Bc <0.001*
Dr 11.68±1.23Bb 18.07±3.67Aa 11.44±0.80Bb <0.001*
Dg 10.22±2.42Bb 16.44±2.78Aa 11.17±2.39Bb <0.001*
De 13.01±1.70Bb 18.47±4.88Aa 21.42±1.84Aa <0.001*
p-value <0.001* <0.001* <0.001*
Different superscript small letters indicate a statistically significant difference within the same vertical column; Different superscript capital
letters indicate a statistically significant difference within the same horizontal row; *significant (p<0.05).
Figure 2 - Bar chart showing average microshear bond strength (MPa) values in different bonding stages.
Figure 3 - Bar chart showing average microshear bond strength (MPa) values in different decontamination protocols.
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El-Safty MMM et al.
Effect of saliva contamination and different decontamination protocols on microshear bond strength of a universal adhesive to dentin
El-Safty MMM et al. Effect of saliva contamination and different decontamination
protocols on microshear bond strength of a universal adhesive
to dentin
The effect of saliva contamination to different
substrates was discussed in the literature [24-26],
and the need for decontamination protocols to
restore bond strength was highly recommended due
to its high clinical signicance. Up to this point, it
is hard to say we have enough information about
the ideal decontamination protocol to overcome
the negative effect of saliva contamination on bond
strength to dentin of universal adhesives during
different bonding stages.
Universal adhesives became more commonly
used by dental clinicians due to their versatility
and ease of use. All-Bond Universal (ABU) is a
popular adhesive containing 10-MDP, crucial for
durability of dentin bond strength of universal
adhesives [27]. ABU was used in self-etch
mode as previous studies showed no signicant
difference between bond strength values when
used in self-etch and etch-and-rinse modes and it
was also recorded that self-etch mode improved
bond durability after water storage [28].
Saliva contamination before curing of the
adhesive may have led to retention of additional
water molecules within the adhesive layer
decreasing the degree of monomer conversion
resulting in weak adhesive and reduced bond
strength [29]. On the other hand, when saliva
contamination occurred after curing of the
adhesive, the adherence of salivary proteins to
the oxygen inhibited layer of the adhesive could
prevent the proper tallying and copolymerization
of the following resin layer and thus similarly
decreasing the bond strength [30]. Hence, for
decontamination, rinsing, grinding with SiC
grit 600, were used to attempt to mechanically
remove the saliva contaminated surface
and regain the bond strength. Alternatively,
ethanol as a proven organic solvent may be
able to dissolve the salivary glycoproteins from
the contaminated surface, as well as excess
moisture [31]. This is in correspondence to
literature using ethanol for multiple reasons with
regards to adhesive dentistry [32-34]. All the
decontamination methods used in this study
aimed to remove the salivary contaminated layer
either chemically or mechanically. The variation
in the decontamination protocols chosen in this
study was specifically aimed at showing the
potential effect of both method of removal and
resultant smear layer on adhesive layer formed.
The results of our study for microshear
testing after 24 hours showed that the three
decontamination protocols used in this study were
effective in improving the bond strength levels
compared to Cb D0 when saliva contamination
occurred before light curing of the adhesive.
Distinctively, when saliva contamination occurred
after light curing of the adhesive, ethanol
recorded the highest bond strength values
followed by rinsing and grinding then CaD0.
Therefore, the null hypotheses could be rejected.
Our results for contamination occurring
before curing of the adhesive
are in agreement
with the results of other studies. Brauchli et al.
[35], and Tuncer et al. [36] similarly concluded
that just water rinsing, simple drying and
reapplication of the bonding agent was enough
to achieve good bond strength after salivary
contamination. They also suggested that the
acidic monomer component of self-etch adhesives
may be able to degrade and denature the
salivary proteins thus overcoming the effect
of salivary contamination and providing good
bonding. The acidity of universal adhesives is
determined according to the concentration of
10-MDP functional monomer [37]. Therefore,
the results of our study may be attributed to
the MDP- containing universal ABU that may
have overcome the barrier effect of salivary
glycoproteins, increasing the stability of the
adhesive, reducing its hydrolytic degradation
and forming strong and stable ionic bonds with
hydroxyapatite crystals. All Bond Universal is also
known for its low water content that contributes
to more moisture resistance [38].
Therefore, the results of our study may be
attributed to the MDP- containing universal ABU
that may have overcome the barrier effect of
salivary glycoproteins, increasing the stability of
the adhesive, reducing its hydrolytic degradation,
and forming strong and stable ionic bonds with
hydroxyapatite crystals. All Bond Universal is also
known for its low water content that contributes
to more moisture resistance.
Moreover, reapplication of the adhesive
could aid in recovering the bond strength.
ABU contains ethanol and water as solvents.
While water is effective in re-expanding collapsed
collagen network if excessive drying was used,
ethanol has the ability to remove the organic
molecules of saliva that were attached to the
bonded surface [39]. This is in harmony with
Cobanoglu et al. [40] who reported that repriming
of the contaminated surface recovered the bond
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Effect of saliva contamination and different decontamination protocols on microshear bond strength of a universal adhesive to dentin
El-Safty MMM et al. Effect of saliva contamination and different decontamination
protocols on microshear bond strength of a universal adhesive
to dentin
strength in one of the adhesives tested (Optibond
Solo Plus SE, ph=1.4) [30,41]. Afshar et al. [42]
conducted a similar study but using a two-step
total etch adhesive (Single Bond). In the same
way, they reported that decontamination of
uncured adhesive layer with water rinsing
then reapplication of the adhesive could result
in bond strength values close to that of the
uncontaminated control group.
In our study, a SiC grit 600 (equivalent to
the yellow-coded nishing stone) [43] was used
for 10s. This simulated the mechanical action
of the drill as a decontamination protocol and
was able to bring the bond strength values of
the contaminated group closer to those of the
control group (C0D0). Grinding is believed to
mechanically remove the saliva contaminated
surface and regain the bond strength. On the
contrary to our results, Ghavam [44] reported
that decontamination with water rinsing or
mechanical removal of the contaminated layer
using a bur resulted in no signicant difference
when compared to the control uncontaminated
group. However, Ghavam did not mention further
details regarding bur type, pressure or time of
application.
Ethanol solvent in ABU has a water chasing
ability allowing better removal of excess water
from saliva without affecting the bonding
agent [45,46]. This may suggest that ethanol
component in ABU (30-60%) [47] was not
autonomously enough to overcome the effect of
saliva contamination. However, when used as a
decontamination protocol, surplus amounts of
ethanol were able to remove the residual amount
of water from the contaminated surface. This may
explain the observed effectiveness of ethanol as
a decontamination protocol in recovering the
bond strength values in our study when salivary
contamination occurred before curing.
Regarding saliva contamination after curing
of the adhesive, decontamination by ethanol
was effective in significantly improving the
bond strength values followed by rinsing and
grinding compared to Ca D0. It is believed that
the contaminated adhesive layer should be
removed in order to not interfere with surface
energy, cleanliness and interfacial adaptation.
The salivary glycoproteins were assumed to
act as a barrier and prevent copolymerization
with the following layer [36]. Ethanol as an
organic solvent, may be able to better remove
the salivary glycoproteins from the bonded
surface as well as decreasing the surface tension
of water present in saliva causing more water
dispersion leading to better adhesion [29]. This
result was similar to the work of Tahlan and
Garg [48] where ethanol showed higher shear
bond strength values than water rinsing or
phosphoric acid etching when used with another
ethanol-based self-etch adhesive Tetric N-Bond
(Ivoclar Vivadent). Conversely, Chasqueira et al.
[49] found no differences between water and
ethanol as decontamination protocols after saliva
contamination after curing of the adhesive.
In previous studies, grinding has not been
used for decontamination except for two instances
with conicting results [44,50]. Grinding with
SiC may account for embedding of the salivary
glycoproteins into the dentinal tubules and
interfere with proper adhesive inltration and
thus reducing the bond strength. Our results
when saliva contamination occurred after
curing of the adhesive were in disagreement
with Furuse et al. [50] where decontamination
through abrasion with nishing disks enhanced
the resin-resin bonding after saliva contamination
while decontamination by water rinsing and
drying did not establish a good bond strength.
This may be attributed to Furuse adding an
etching step following grinding which may alter
surface topography. Independent phosphoric acid
etching may have effectively removed the salivary
glycoproteins, much more effectively than ABU in
self-etch mode. Meanwhile, smear layer density
and thickness created during grinding may
interfere with complete monomer inltration or
buffer capacity [51].
Water rinsing failed to recover bond
strength values of the control group and also
recorded multiple pre-test failures, not evident
in uncontaminated bonding. Anjum et al. [52]
condemned water rinsing as a method for salivary
decontamination and considered water rinsing
be worse than the salivary contamination itself.
Generally, the presence of excess remaining water
may negatively affect results. Conversely in our
study, water rinsing yielded better microshear
bond strength values than Ca-D0. This is in
alignment to Kim et al. [53] who reported that
with ABU, simple rinsing (5s) and drying could
be effective in restoring the bond strength after
saliva contamination. In addition, reapplication of
the adhesive could lead to further improvement
of the bond strength.
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El-Safty MMM et al.
Effect of saliva contamination and different decontamination protocols on microshear bond strength of a universal adhesive to dentin
El-Safty MMM et al. Effect of saliva contamination and different decontamination
protocols on microshear bond strength of a universal adhesive
to dentin
CONCLUSIONS
Using a simplied, single step, self-etch adhesive
does not make it immune to salivary contamination.
It is worth noting that decontamination protocols
when applied without saliva contamination led to
signicant reduction in the bond strength values.
From a clinical point of view, this may highlight that
decontamination protocols could have their own
compound negative side effects on bond strength,
thus must be chosen carefully. Nevertheless, when
decontamination is overlooked, clinical performance
and durability of both adhesive and restoration are
compromised. Finally, decontamination protocols
have varying efciency in restoring bond strength.
All decontamination protocols were dependable
before curing, and ethanol appears to be most
effective both before and after curing.
Author’s Contributions
MMMES: Conceptualization, Methodology,
Formal Analysis, Investigation, Resources, Data
Curation, Writing – Original Draft Preparation,
Writing – Review & Editing, Visualization,
Supervision. KAN: Methodology, Visualization,
Supervision. DSM: Methodology, Writing –
Original Draft Preparation, Writing – Review &
Editing, Visualization, Supervision.
Conict of Interest
The authors have no proprietary, nancial,
or other personal interest of any nature or kind
in any product, service, and/or company that is
presented in this article.
Funding
This research did not receive any specic
grant from funding agencies in the public,
commercial, or not-for-prot sectors.
Regulatory Statement
Research proposal approved by the Research
Ethics Committee at the Faculty of Dentistry Ain
Shams University, Cairo, Egypt (FDASU-Rec
D031822).
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Mohamed Motaz Mohamed El-Safty
(Corresponding address)
Badr University in Cairo, Department of Conservative Dentistry, Cairo, Egypt.
Email: mohamed.moataz@buc.edu.eg
Date submitted: 2023 Nov 18
Accept submission: 2024 Apr 02
