Reducing Aerosol And Bioaerosol Using Different Oral Suctions In Dental Clinic, Randomized Clinical Trial
Phase: NA
Conditions: Infections, Oral Infection
Sponsor: King Abdulaziz University

EffectivenessofExtra- oralSuction
Comparing to Other Suction in Reducing
Particles MatterandBioaerosol in Dental
Clinic, RandomizedClinical Trial.
NCT05848245
September 15, 2022
Abraar Bannan
Supervised by
Prof. Iman Kamel, Dr. Zuhair Natto, Dr. Naif Almakishah
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Content table
.1
.2
Abstract in English .......................................................................................... 3
Introduction ..................................................................................................... 4
Background 3.1 ................................................................................................................................... 4
Rational of research 3.2....................................................................................................................... 5
Objective 3.3 ....................................................................................................................................... 5
MATERIAL AND METHODS .4 ...................................................................................................... 5
Study design 4.1.................................................................................................................................. 5
Intervention devices 4.2....................................................................................................................... 5
Intervention groups 4.3........................................................................................................................ 6
Study area and setting 4.4.................................................................................................................... 6
Assessment 4.5.................................................................................................................................... 6
Study participants 4.6.......................................................................................................................... 7
Sample size 4.7.................................................................................................................................... 7
Sampling technique 4.8....................................................................................................................... 7
Inclusion and exclusion criteria 4.9..................................................................................................... 7
Variables and Data collection 4.10...................................................................................................... 7
Statistical consideration 4.11............................................................................................................... 9
Ethical consideration 4.12................................................................................................................... 9
Limitation and strength 4.13................................................................................................................9
Devices and setting figure .5............................................................................................................. 10
.6
References ..................................................................................................... 12
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1. Abstract in English
Aerosol particles generated when using dental instrument such as ultrasonic and high air
driven handpieces, this aerosol is mixture of blood, saliva, infectious agents, and dental
materials. Inhaler dust that range between PM2.5 to PM10 could transferred to the human
lung’s terminal bronchioles and alveoli that cause a harm effect.
The aim of this study to assess the effectiveness of different dental suction devices that could
be contributed to decrease risk of particles count, Bacterial and fungal that arising from
patient mouth to indoor air dental clinic
This is a randomized clinical trial will be conducted in three different places: educational
hospital, public hospital, and private clinic. In each place 40 subject will be recruited.
Measurement including particles count and microorganism will be taken before 15 minutes
and during of scaling and prophylaxis procedure to measure particles count, oral bacteria,
fungus, and microbial air. In this study will be compared between four intervention groups;
Group A with high and low suction only, Group B using dry shield suction and low section,
Group C using extra-oral suction with high and low suction, and Group D using dry shield
suction and extra-oral suction and low section. Difference between each categorical groups
and particle, oral bacterial, fungus, and microbial air concentration will be tested using two-
way ANOVA test or one way ANOVA test. Statistical analysis will be carried using STATA
version 13.
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2. Introduction
2.1 Background
Aerosols described as any fluid and solid particles dropped in the air. Any particles less than
50 micrometer in diameter could be suspended into air for extended period before rest on
environmental surfaces or enter respiratory tract(1). Bioaerosol Are a complex mixture of
airborne particles of biological origin such as bacteria, viruses, and fungus.
In dental clinic, dental team are exposed to infectious droplet through a direct contact with
body fluid of patient, contact with environmental surfaces or instrument(2). Dental aerosol
might be not easily to measure. However, many studies assess the amount of bacteria using
bacteria growth media such as blood agar culture(1). In addition, particle number
concentrations are considered to more closely indicate the health exposure risk to characterize
cleanroom. Particles in the range of 0.5–10 µm diameter can be inhaled and held on the
human lung’s terminal bronchioles and alveoli(3). Dental instruments and procedure generate
varies air-borne contamination amount, the highest bacterial growth was produced by ultra-
sonic scaler, followed by the air-driven high-speed handpiece, the air polisher and various
other instruments such as the airwater syringe and prophylaxis angles(4-6). In addition, one
of study in vitro was found the high amount of aerosol and spatter generated from ultrasonic
scalar if used without cooling and presence of small amounts of liquid placed at the operative
site to mimic blood and saliva (7)
Using personal protective barrier would be prevented spatter droplets but particles which is
less than 50 micrometer that consist of infectious agent has the potential to enter the
respiratory tract through leaks in masks (8). The exact hazard effects of dental aerosol not
possible to recognize currently however the probable spread of infection should be minimized
and eliminated (1).
Nowadays in the market we have new devices might reduce the amount of particles in air
such as extra-oral suction (EOS). There is some study evaluate the influence of EOS, they
found EOS is effective in reducing droplets (9-15). However, most of these study(9-11, 14-
16) was perform in vitro on Manikin head and measure particles concentration, that give us
some indication of effectiveness of EOS but still it is not precise due to different factors that
present in patient mouth such as saliva, blood and infectious agent.
Other study that were done in vitro using Zirc suction -that work as dryshield suction- show
efficiency of reduction in aerosol by 88% comparing to other groups(17).
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The aim of this study to assess the effectiveness of different dental suction devices that could
be contributed to decrease risk of particles count, Bacterial and fungal that arising from
patient mouth to indoor air dental clinic
2.2 Rational of research
Most of the previous studies used a low numbers of sample size and the majority of them
were conducted in vitro. In addition, they assessed either amount of bacteria or particles
comparing EOS to baseline.
In this study, we will analyze particles count and microorganisms comparing EOS to
dryshield, combined group and standard group.
2.3 Objective
1. Measure particles, bacteria and fungus that arising from patient's mouth in each group.
2. Evaluate health exposure risk for each group to baseline reading (pre-test).
3. Compare health exposure risk for each group to standard group ( Group A)
4. Compare health exposure risk between each of the following groups A, B , C and D.
3. MATERIAL AND METHODS
3.1 Study design
Randomize clinical trial
3.2 Intervention devices
1. Extra oral suction
EOS is used to remove aerosol and droplet that arising from patient mouth and filtering the
air.
2. All in one system (dryshield suction)
Dryshied suction is unites of high volume suction and saliva ejection with a bite block,
tongue, and oral pathway protection.
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3.3 Intervention groups
Group A with high and low suction only ( standard care),
Group B using dry shield suction and low section
Group C using extra-oral suction with high and low suction
Group D using dry shield suction and extra-oral suction and low section.
3.4 Study area and setting
1. This study will be conducted in close rooms at educational hospital, public hospital and
private dental clinic. Humidity and temperature will be recorded at the beginning,
measuring particles oral bacteria and fungus will be performed 15 minutes before and
approximately 15 minutes during scaling and prophylaxes procedure in two opposite
quadrants in left side. Additionally 5 minutes will require between two interval to allow
cleaning process of filter in Digital dust monitor. Microbial sampler devices will be
distributed at several locations in room, three microbial air sampler devices around
patient, at 8 o'clock position, 1 o'clock position and 4 o'clock. Another device that will be
placed near to air condition and one agar media on the floor to control another microbial
agents that could be arising from A.C.. Intervention devices that will be used is EOS
where being place on left side of patent to allow comfortable movement of hygienist and
suction cone will be away from patient mouth from 10 -15 cm based on manufacture
instruction.
3.5 Assessment
Risk
Noise that will be caused by dental suction and other measurement devices.
patient could spend additional time in dental clinic before procedure starting
Benefit
Experience more comfortable treatment setting than routine setting
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Alternative
Subjects have all rights to withdraw from study at any time for any reasons. In addition,
scaling and prophylaxis treatment will be completed as usual.
3.6 Study participants
Patients from King Abdulaziz dental hospital, dental private office, and King Fahad hospital
3.7 Sample size
Total sample will be 120 subjects.
3.8 Sampling technique
Multiple stage stratified random sampling at place level then subject randomly assign from
schedule appointment using simple random sampling. Last stage, Simple random sampling of
40 subject at each 4 groups using computer-generated random numbers.
3.9 Inclusion and exclusion criteria
Inclusion criteria
Adult patient above 18 years of age, who has schedule appointment in dental hygienist clinic
for scaling and prophylaxis procedure.
Exclusion criteria
Any room have additional mechanical ventilation rather than air conditioner and orthodontic
patient will be excluded.
3.10 Variables and Data collection
Measurement devices
2. Digital dust monitor
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Particles matter will be measured using Digital dust monitor (model 3443, KANOMAX.USA
INC., made in Japan). This device measure particle size that range from 0.1 to 10 Mm using
light scattering method (semiconductor laser radiation light source ) with flow rate 1 L/min.
air is collect through a filter which is built-in in order to eliminate coarse particles. Filter is
reusable and it needs approximately 5 minutes cleaning time depending on environment.
Minimum, maximum, and average concentration result show among measurement time.
Calibration of device will be performed according to manufacture instruction.
3. Microbial air sampler device (sampl’air ASE)
Is considered as active air sampler method which used to collect microorganism onto solid
media with flow rate 100 L/ min. Positive hole conversion table should be used in order to
counting colony; colony forming units per volume of air (CFU m−3).
In this study a specific agar media will be used to collect oral bacteria and fungus.
Outcome variable
Particle count level (difference in PN count[ ΔPN ;post-test – pre-test , counts/ m3])
(continuous variable)
Average of oral bacterial concentration before and during procedure
Average of fungus concentration before and during procedure
Microbial air concentration including bacteria and fungus before and during procedure (floor
and near to A.C)
Explanatory variable
Categorical variable
Place ,intervention groups, order of patient ,gender and supragingival calculus (mild,
moderate, heavy) ,
Continuous variable
time of procedure that staring from the beginning of scaling until finishing of scaling (in
minutes), time on day (morning, afternoon), age, year experience of hygienist, distance of
room, humidity, and room temperature.
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3.11 Statistical consideration
All continuous variables will be express as mean and stander deviation
All categorical variables will be described as frequency and percentage
Difference between baseline and during of procedure measurement intended for particle, oral
bacteria, fungus and microbial air concentration will be calculating using pairwise t test.
Difference between each categorical groups and particle, oral bacterial, fungus, and microbial
air concentration will be tested using two way ANOVA test or one way ANOVA test
Strength and direction of association between particle count levels and time of procedure will
be tested using correlation test
Multiple linear regression model will be built to predict particles count level with entrance
value of 0.01 and exit value 0.101. Confidence level of 95% will be computed and p-value
less than 0.05 will be considered as significant.
3.12 Ethical consideration
Ethical approval will be provided from institutional ethics review. Consent form would be
presented by investigator for each subject before experimental trial. Subject will require
reading and signing.
To confirm confidentiality of participant information, each participant will get a unique
alphanumeric code. The information will only be shared between the researchers.
There is no payment and transportation provide to participants.
3.13 Limitation and strength
Randomly involved of subject into intervention groups is one of strength in our study. One of
limitation is subject and observer could not be blind.
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4. Devices and setting figure
Name
Picture
a) High volume suction
b) Low volume suction
a
b
All in one system (dry-shield)
Extra oral suction
Microbial air sampler device (sampl’air
ASE)
10

Digital dust monitor , KANOMAX , model
3443,
Circles represent location of microbial air
sampler device
Square represents digital dust monitor
device
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5. References
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