Art-1_Taraboanta
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Original Articles
EVALUATION OF THE SALIVARY PARAMETERS IN
FACIAL MASK WEARERS DURING COVID-19 PANDEMIC
1a 1b 1c 1d 1e
Ionuț Tărăboanță , Simona Stoleriu , Gianina Iovan , Angela Cristina Ghiorghe , Irina Nica ,
1f 1g
Andra Claudia Tărăboanță-Gamen , Sorin Andrian
¹Department of Odontology, Periodontology and Fixed Prosthodontics, Faculty of Dental Medicine, "Grigore T. Popa" University of Medicine and Pharmacy
of Jassy, Jassy, Romania
aDDS, PhD Student; e-mail: ionut-taraboanta@umfiasi.ro; ORCIDiD: https://orcid.org/0000-0001-5452-916X
bDDS, PhD, Associate Professor; e-mail: stoleriu_simona@yahoo.com; ORCIDiD: https://orcid.org/0000-0001-5427-6027
cDDS, PhD, Professor; e-mail: gianina.iovan@umfiasi.ro; ORCIDiD: https://orcid.org/0000-0001-7255-4406
dDDS, PhD, Associate Professor; e-mail: cristina.ghiorghe@umfiasi.ro; ORCIDiD: https://orcid.org/0000-0002-1636-6686
eDDS, PhD, Assistant Professor: irina.nica@umfiasi.ro; ORCIDiD: https://orcid.org/0000-0003-1189-0785
fDDS, PhD Student; e-mail: andra-claudia.gamen@umfiasi.ro; ORCIDiD: https://orcid.org/0000-0003-0510-6149
gDDS, PhD, Professor: sorin.andrian@umfiasi.ro; ORCIDiD: https://orcid.org/0000-0002-9271-6123
ABSTRACT https://doi.org/10.25241/stomaeduj.2021.8(4).art.1
Introduction The COVID-19 pandemic situation forced governments to impose various measures to reduce
the spread of the virus. The most used method is to wear facial masks, which can be found under several
commercial forms. Wearing facial masks has caused a lot of controversy and rumors. Among them, many
patients and practitioners have complained of a dry mouth after wearing different types of facial masks for
a variable period of time. The aim of this study was to analyze the quantitative (un-/stimulated salivary flow
rate) and qualitative (pH and buffer capacity) changes in saliva in mask wearers.
Methodology Forty subjects were selected for this study. All of them wore alternatively no mask, a surgical
mask for 2 hours, and FFP2 mask for 2 hours (groups 1, 2, and 3). Saliva samples were collected from all the
subjects in the groups and analyzed to determine the values of un-/stimulated salivary flow rate, the pH, and
buffer capacity using GC Saliva-Check Buffer (GC Corporation, Japan). Descriptive and analytical statistics
were performed using ANOVA and Bonferroni post-hoc test.
Results For unstimulated saliva samples, between groups 1 and 3, statistically significant differences were
recorded, with a significance level of 0,02<p=0,05. For stimulated saliva, salivary pH or buffer samples, no
significant differences were found between groups.
Conclusion Wearing FFP2 masks for two hours showed a reduction in salivary flow rate compared to subjects
who did not wear facial masks. Wearing surgical masks did not produce changes in salivary flow rates, pH or
buffer capacity.
KEYWORDS
Mask; COVID-19; Saliva; pH; Buffer Capacity.
1. INTRODUCTION methods to reduce the spread of the disease. The
lack of effective treatments against the virus, as
The first cases of the novel coronavirus 2019 well as its rapid and uncontrollable evolution,
(COVID-19) appeared in Wuhan, China, in December forced the authorities to impose a series of non-
2019. The rapid spread of severe acute respiratory pharmacological measures to limit the spread of the
syndrome coronavirus 2 (SARS-CoV-2) forced the virus, such as maintaining hand hygiene, keeping
World Health Organization (WHO) on March 11,
social distance and wearing facial masks [1,2]. The
2020 to announce a global pandemic situation [1],
disrupting and creating difficulties for governments existence of solid evidence that the SARS-CoV-2
and national health systems in managing it [2]. virus would be transmitted by air has strengthened
Throughout this period, the scientific communities the belief that the use of face masks would be an
around the world have been looking for some effective way to reduce the spread of the virus [2,3,4].
OPEN ACCESS This is an Open Access article under the CC BY-NC 4.0 license.
Peer-Reviewed Article
Citation: Tărăboanță I, Stoleriu S, Iovan G, Ghiorghe AC, Nica I, Tărăboanță-Gamen AC, Andrian S. Evaluation of the salivary parameters in facial mask
wearers during COVID-19 pandemic. Stoma Edu J. 2021;8(4):233-238
Received: December 01, 2021; Revised: December 11, 2021; Accepted: December 16, 2021; Published: December 20, 2021
*Corresponding author: Dr. Simona Stoleriu, 16, Universității Str., RO-700115 Jassy, Romania
Tel.: +40745106066; Fax: +40.232.211.820; e-mail: stoleriu_simona@yahoo.com
Copyright: © 2021 the Editorial Council for the Stomatology Edu Journal.
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Tărăboanță I, et al.
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Since the beginning of the pandemic, protective 26.05.2021) approved by the Ethics Committee of
Original Articles masks have been recommended as protective “Grigore T. Popa” University of Jassy, Jassy Romania.
measures due to the fact that the transmission of The selection of subjects was made in accordance
the virus is mainly respiratory. Countries have issued with the inclusion and exclusion criteria presented in
instructions and guidelines on the use of protective Table 1.
masks. In Romania, they must comply with the Table 1. Selection of the subjects: inclusion and exclusion criteria.
Personal Protective Equipment Regulation and
with the relevant European standard EN 149. If they Inclusion criteria Exclusion criteria
are manufactured in accordance with the current - Patients aged between 20 and - Patients with general
standards wearing a facial mask was considered one 30 years pathologies that affect salivary
- Patients without associated activity
of the most effective ways to stop the spread of the
general pathologies - Patients with chronic
virus. - Adult female / male volunteer alcoholism
Facial masks are devices that completely or partially - Agreement signed and dated - Patients with viral infections -
cover the face with the role of protection against for participation in the study C / B virus, HIV / AIDS
pollutants or pathogenic microorganisms. Surgical - Ability to understand the - Patients who have an
masks also known as medical mouth-nose protection purpose and type of the study uncooperative attitude
- Willingness to cooperate with
(MNP) are devices that partially cover the face and the doctor and to comply with
act as protection against pathogenic microorganisms the requirements of the study
reducing the risk of spreading drops during
expiration. Surgical masks are not watertight and 2.2. Study design
cannot provide complete protection to the wearer For each subject, salivary parameters: unstimulated
[5].
salivary flow rate, stimulated salivary flow rate, pH
FFP2 face masks (Filtering Face Piece) also known
and buffer capacity were determined using GC Saliva
as N95 masks, provide 95% protection against
Check Buffer test kit, GC Corporation, Japan, (LOT
pathogenic microorganisms. FFP2 masks may or
no. 2003102) at the same time of day (between 11-
may not be equipped with a valve. Masks without
valves ensure effective protection of the external 12 AM), in three different days. On the first day of
environment while masks with valves allow the testing, salivary parameters were evaluated in all
exhaled air to escape without being filtered [4,5]. subjects without wearing any mask (group 1), on the
A number of studies have shown harmful effects second day of testing after wearing a surgical mask
of wearing a face mask on the cardio-respiratory for 2 hours (group 2) and on the third day of testing
system or on the neurological system [1,6], but no after wearing a FFP 2 mask for 2 hours (group 3). The
studies have yet been conducted to evaluate the individuals were recommended to follow the same
effects of wearing a face mask on saliva parameters. schedule, to consume the same food and the same
Saliva has a multitude of functions that maintain the amount of liquids and use the same dental hygiene
body homeostasis, but among them we focused on products and methods on each day of three testing
functions in the oral cavity. Saliva is very important in days. The subjects were asked to avoid eating two
protecting dentition by salivary mucin or proline-rich hours before the salivary tests. Unstimulated salivary
glycoproteins pellicle, has a remineralizing role due to flow rate was initially assessed. From the collected
the content of calcium, phosphate and fluoride ions, saliva, the evaluations of the buffer capacity and
buffering capacity due to bicarbonate and phosphate salivary pH were performed, and finally the stimulated
and antibacterial role due to the presence of IgA, IgG, salivary flow was evaluated, after the subject chewed
IgM or some enzymes [7]. Therefore, any quantitative a piece of paraffin.
or qualitative change in saliva could impair the
protective capacity of saliva on the dentition. 2.3. Salivary tests
Therefore, the aim of this study is to evaluate the The quantitative determination of stimulated and
quantitative and qualitative parameters of saliva in
unstimulated salivary flow rate, buffer capacity and
surgical mask and FFP2 wearers during the COVID-19
salivary pH were performed using the methodology
pandemic.
presented in table 2.
2. MATERIALS AND METHODS
2.4. Facial masks
2.1. Subjects The study participants wore two different types of
The present study was conducted between June facial masks:
1st, 2021 - September 30th, 2021, on a number of 1. surgical masks (AVE, Romania) with three layers:
40 subjects aged between 20 and 30 years old (18 Outer layer-non-woven synthetic material - 20 g/sq;
females and 22 males) all of them being students Middle layer-fused synthetic material, white; Inner
of the Faculty of Dental Medicine, "Grigore T. Popa" layer-non-woven synthetic material, white - 20 g/
University of Iasi. The subjects were informed about sqm
the procedures, they agreed to voluntarily participate 2. FFP 2 masks (3M Aura 9320+, MN, USA) with four
in the study and signed an ethical agreement (no. 84/ layers.
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Original Articles
Table 2. Description of the saliva testing methodology.
Parameters Methodology
to evaluate
Stimulated The assessment was performed using a
salivary flow sialometer in which the patient eliminated
the accumulated saliva at every minute, for
a total period of 5 minutes. Stimulation of
salivary secretion was done with a paraffin
gum. The gum was by chewed by the
subjects for 5 minutes during the whole
period of stimulated saliva collection,
Figure 1. Boxplot presentation of the distribution of the values recorded
according to the manufacturer’s instructions.
in groups 1, 2 and 3 for unstimulated saliva samples.
The measurement was made by three
investigators. The values are expressed in ml/ For stimulated saliva samples, the mean values and
min. standard deviation of group 1 was 10.95 (SD ±2,58),
Unstimulated The assessment was made using a sialometer for group 2 it was 10.93 (SD ±2,31) and for group 3 it
salivary flow in which the patient eliminated the was 10.92 (SD ±1,95). Analyzing the mean variation,
accumulated saliva at every minute, for a total we can see that the values obtained in group 1
period of 5 minutes. The measurement was decrease in group 2 and the values recorded in group
made by three investigators. The values are 2 decrease in group 3 (Fig. 2). Between groups 1, 2
expressed in ml/min. and 3 no statistically significant differences were
Buffer The assessment was made using an indicator recorded for a significance level of p=0.05.
capacity strip for buffer capacity on which a drop of
unstimulated saliva was placed. The color
modification was optically assessed by three
investigators. green – 4 points
green/blue – 3 points
blue – 2 points
red/blue – 1 point
red – 0 points.
The points were counted and the result
determined the buffering capacity score:
0 – 5 points as very low buffering ability
6 – 9 points as low Figure 2. Boxplot presentation of the distribution of the values recorded
10 – 12 points as normal/high in groups 1, 2 and 3 for unstimulated saliva samples.
Salivary pH The assessment was performed using
a pH indicator strip on which a drop of For salivary pH, the mean values and standard
unstimulated saliva was placed. The color deviation of group 1 was 6.72 (SD ±0,19), for group
modification was optically assessed by three 2 it was 6.81 (SD ±0.24) and for group 3 it was 6.83
investigators. (SD ±0.23). Analyzing the mean variation, we can see
that the values obtained in group 1 increase in group
2 and the values recgroups 1, 2 and 3 no statistically
2.5. Statistical analysis significant differences were recorded for a significance
The data were stored in the Office Excel program and level of p=0.05.
the statistical analysis was performed using IBM SPSS For salivary pH, the mean values and standard devia-
26 program. To determine the differences between tion of group 1 was 6.72 (SD ±0,19), for group 2 it was
6.81 (SD ±0.24) and for group 3 it was 6.83 (SD ±0.23).
the study groups we used the repeated measures
Analyzing the mean variation, we can see that the
ANOVA statistical test and the Bonferroni post-hoc values obtained in group 1 increase in group 2 and the
test. values recorded in group 2 increase in group 3 (Fig. 3).
Between groups 1, 2 and 3 no statistically significant
3. RESULTS differences were recorded for a significance level of
For unstimulated saliva samples, the mean values p=0.05.
and standard deviation (SD) of group 1 was 3.53 (SD
±0,68), for group 2 was 3.19 (SD ±0,58) and for group
3 was 3.06 (SD ±0,52). Analyzing the mean variation,
we can see that the values obtained in group 1
decrease in group 2 and the values recorded in group
2 decrease in group 3 (Fig. 1). Between groups 1 and
3, statistically significant differences were recorded,
with a significance level of 0,02<p=0.05. Between
groups 1 and 2, and groups 2 and 3, no significant Figure 3. Boxplot presentation of the distribution of the values recorded
differences were recorded. in groups 1, 2 and 3 for salivary pH.
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caries risk did not find significant correlations between
Original Articles
them [7,16]. This conclusion is explained by the fact
that bicarbonate and other buffering components do
not come into direct contact with the surface of the
teeth as they are covered by a layer of bacterial film
or biofilm [7,17].
Another symptom of mask wearers is halitosis,
also called “mask breath” caused by volatile
sulfur compounds in the oral environment or by
Figure 4. Boxplot presentation of the distribution of the values recorded the remaining fermentable food residues on the
in groups 1, 2 and 3 for buffer capacity. dorsum of the tongue or on the dental surfaces and
accentuated by oral dryness [8,18].
4. DISCUSSION
Wearing the facial mask not only produces
In this study we evaluated the rate of unstimulated imbalances in the oral environment, but also affects
and stimulated salivary flow, buffer capacity and the perioral teguments, causing their dehydration and
salivary pH in subjects wearing or not a surgical mask potentiating the bacterial action that will cause cracks
and a FFP2 mask. The results indicate a reduction or ulcerations of the tegument or angular cheilitis
in the resting salivary flow in FFP2 mask wearers [8,19].
compared to subjects that did not wore any type of Some recent studies have described a number
mask, and these findings are supported by a recent of recommendations to combat oral imbalances.
review study conducted by Muley-Itke that described
Therefore, in addition to a rigorous oral hygiene that
the phenomenon of "Mask mouth" as being a
result of prolonged wearing of the facial mask. This must include 2-3 toothbrushes, the use of mouthwash
condition can be a consequence of hyposalivation due and dental floss to combat the phenomenon of "mask
to oral breathing that is a common behavior in facial mouth", the surgical masks must be changed after
mask wearers and is associated with an increased 3 hours of wearing because the humidity expired
incidence of oral disorders, such as periodontal degrades them. Oral breathing should be avoided
disorders, halitosis or an increased carious risk. as much as possible when the mask is applied. The
Another justification may be poor hydration while mask must be applied correctly, as tightly as possible
wearing a mask that may be associated with general and used only once. To avoid perioral skin lesions, it
dehydration. Dental or periodontal diseases have an
increased incidence in oral respiratory patients, as is recommended to use creams with moisturizing and
the mouth has a very high exposure to air flow, which emollient effect [20-22].
decreases the rate of salivary flow [8,9].
A number of studies have shown a significant increase 5. CONCLUSION
in the amount of acidogenic and aciduric bacteria such
as Streptococcus mutans and Lactobacilli in patients Unstimulated salivary flow rate decreases in persons
with oral breathing or those with xerostomia. [8,10]. wearing FFP2 mask when comparing to the persons
Other authors have described in patients with who wear no mask, but it remains unaffected by
hyposalivation or oral respiration, an increase in
surgical mask wearing.
bacterial plaque indices as well as a reduction in
the buffer capacity of saliva and an increase in Stimulated salivary flow rate, salivary pH or buffer
susceptibility to gingival inflammation or periodontal capacity are not influenced by any type of face masks.
disease [8,10,11].
The decrease of the salivary flow rate will AUTHOR CONTRIBUTIONS
consequently decrease the antibacterial components
increasing the potential for the development of IT: conception and design of the study, acquisition of data,
bacterial or fungal infections, such as candidiasis. statistical analysis and interpretation of data, drafting the article,
Decreasing the concentration of lysozyme, lactoferrin,
final approval of the version to be submitted. SS: drafting the
lactoperoxidase or histatin will weaken the saliva's
defense capacity [8,12,13,14]. article, revising the article critically for important intellectual
Saliva has multiple roles: to ensure surface cleaning, content. GI: acquisition of data, analysis and interpretation of
substance clearance and an optimal pH by buffer data. AG: acquisition of data, analysis and interpretation of
capacity. In buffering effect, an important role is data. IN: acquisition of data, analysis and interpretation of data.
played by the bicarbonate-carbonic acid system, ACTG: acquisition of data, analysis and interpretation of data. SA:
salivary phosphate and proteins [7,15]. conception and design of the study, revising the article critically
Maldupa et al. described a different composition of for important intellectual content, final approval of the version to
unstimulated saliva when comparing to the stimulated
be submitted.
one. Increased saliva production will decrease the
concentration of potassium and phosphate and
will increase the values of sodium, chloride and ACKNOWLEDGMENTS
bicarbonate [7]. Most studies that evaluated the links The authors would like to thank all the participants in the study
between the saliva buffer capacity and the patient's who demonstrated their availability to collaborate in this study.
236 Stoma Edu J. 2021;8(4):233-238 pISSN 2360-2406; eISSN 2502-0285
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Ionuț TĂRĂBOANȚĂ
DDS, PhD student
Discipline of Cariology and Restorative Dentistry
Faculty of Dental Medicine “Grigore T. Popa”
University of Medicine and Pharmacy of Jassy Jassy, Romania
CV
Ionuț Tărăboanță graduated from the Faculty of Dental Medicine, “Grigore T. Popa” University of Medicine and Pharmacy Jassy,
Jassy, Romania in 2016. Since 2016 he has been a PhD student at the Discipline of Cariology and Restorative Dentistry. Since 2018
he has been working as Assistant Lecturer at the same discipline. His fields of interest are the study of saliva and dental materials.
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Questions
Original Articles
1. What is the recommended time to wear a mask before it is necessary to change it?
qa. 1 hour;
qb. 5 hours;
qc. 3 hours;
qd. 30 minutes.
2. What is the meaning of FFP2?
qa. Frontal Filtering Piece;
qb. Filtering Face Piece;
qc. Face Filtering Product;
qd. Free Filtering Piece.
3. The decrease of the salivary flow rate will consequently:
qa. Decrease the antibacterial components;
qb. Decrease the growing potential of the bacteria;
qc. Increase the concentration of lysozyme;
qd. Increase the concentration of lactoferrin.
4. The most important role in buffering capacity is played by:
qa. Lactoperoxidase;
qb Bicarbonate;
qc. Lactobacilli;
qd. Histatin.
https://www.gnydm.com/
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