A two part study comparing the antimicrobial effectiveness of ACT© fluoride and
Crest© mouthwash using samples from human subjects and a laboratory analysis of
their inhibition of Streptococcus mutans growth
Amber Bridges-Brock
Abstract:
The purpose of this study was to examine the effectiveness of mouth rinses containing
sodium fluoride (0.05%) and/or cetylpyridinium chloride (0.07%). The participants in
this study consisted of 45 Saint Martin’s University students who were divided into three
groups. Each group was given a different mouth rinse to use for 14 days. On day 1 and
day 14 oral samples were taken from the subjects and incubated for 72 hours, with optical
density readings at 24, 48, and 72 hours. Optical density tests were analyzed using an
Analysis of Variance (ANOVA) and indicated all rinses significantly reduced bacteria
levels: ACT (F= 8.73, d.f. =1, p=0.006), Crest (F= 13.26, d.f. =1, p=0.001), and control
(F= 6.57, d.f. =1, p= 0.016). Though, there was no significant difference in reduction
across the rinses (F= 0.22, d.f. = 2, p= 0.801). Even though all three rinses, including the
control, decreased in bacterial levels, there was no significant difference between the
three.
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Introduction:
Many species of microorganisms thrive in the warm and nourishing environment
of the mouth. Due to the millions of bacteria that inhabit the mouth, it is no surprise that
if teeth and gums are not properly cared for, dental caries may arise. Accumulated plaque
and tooth decay, which will later lead to deterioration of the gums and tooth enamel, is
known as dental caries (Scherp, 1971). In order to prevent dental caries, individuals can
brush and floss on a regular basis to slow the deterioration of the teeth and gums.
However, preventing deterioration can be difficult. Some bacteria are necessary to have
in the oral cavity and others are not. The most common type of bacteria found in the oral
cavity is Streptococcus mutans (Menendez et al., 2005). Various studies, including
Menendez et al. (2005), Fine et al. (2000), and others have tested the effects of different
types of mouth rinses on levels of S. mutans in the mouth.
Arweiler et al. (2003) examined the antibacterial and plaque-reducing properties
of mouth rinses by testing mouth rinses that contained triclosan, amine fluoride, a
combination of the two, as well as a placebo and a 0.2% chlorohexidine solution for
negative and positive controls. Initially, 15 people volunteered for the study and had their
teeth professionally cleaned. The subjects were asked to refrain from using any oral
hygiene products and procedures during the study. Instead, they rinsed twice daily for 1
minute with 10 mL of one of the five randomly assigned solutions (Arweiler et al., 2003).
The study used clinical parameters that included the plaque index, which analyzes the
levels of plaque within the mouth, at 24 and 96 hour intervals. The area of plaque on the
top and bottom incisors was measured using this index (Arweiler et al., 2003). At each
time interval, a plaque sample was collected to be analyzed and evaluated (Arweiler et al.,
2003). The study concluded that the chlorohexidine solution showed the greatest decrease
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in oral microbial growth at each time interval in comparison to the placebo solution.
Arweiler et al. (2003) also showed that the amine fluoride solution and the combination
of it with triclosan had similar effects on decreasing oral microbial growth. This study
explained the amounts, types, and concentrations of different mouth rinses, as well as
what time intervals should be used. The variables that I chose to include in my study
were to use 10 mL of ACT® fluoride with active ingredients of sodium fluoride (0.05%)
and cetylpyridinium chloride (0.07%). The other mouth rinse that I used was 30 mL of
Crest® mouthwash, with an active ingredient of cetylpyridinium chloride (0.07%). The
participants in the study rinsed for 30 seconds once a day, as recommended by the
manufacturers. Also, Arweiler et al.’s (2003) study showed that an average incubation
time off 24 to 72 hours, is adequate for S. mutans bacteria growth after being exposed to
the mouth rinses.
In order to analyze how certain mouth rinses decrease oral microbial growth, the
optimal rinsing time was investigated. Paraskevas et al. (2005) conducted a study using
erythrosine mouthwash. They used erythrosine as a disclosing agent within the mouth
rinse because, where plaque is present, the plaque becomes visible by this staining agent.
Thirty subjects were randomly divided into two groups. Group 1 rinsed with 10 mL of
erythrosine for two consecutive periods of 15 seconds and one period of 30 seconds, for a
total of 60 seconds. Group 2 rinsed for three consecutive periods of 30 seconds, for a total
of 90 seconds (Paraskevas et al., 2005). After each rinse cycle, new plaque measurements
were taken from teeth surfaces within the mouth. Paraskevas et al. (2005) concluded that
rinsing for 30 seconds was an optimal amount of time for the mouthwash to come in
contact with all the plaque-covering surfaces. I used a rinsing time of 30 seconds for all
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treatments within my study due to Paraskevas et al.’s (2005) findings and the dosages on
the mouth rinse package labels that recommended 30 second rinse times.
In these and other studies, researchers have explored the role of chlorohexidine as
a key element in eliminating oral bacteria. Menendez et al. (2005) tested chlorohexidine
mouthwash as an antimicrobial agent against S. mutans. In the study, 16 healthy adult
subjects were randomly assigned to one of four rinse groups. Each group rinsed twice a
day for 7 days with a chlorohexidine solution, a hydrogen peroxide solution, a
combination of both, or water as a control (Menendez et al., 2005). A new rinse cycle
started every 5 weeks. Saline wash samples were collected on days 7 and 21 for assessing
the levels of S. mutans in the mouth. Their results showed no differences in the S. mutans
levels among the groups. However, the total levels of S. mutans on day 7 were lower than
in the two groups that contained chlorohexidine in the mouth rinse (Menendez et al.,
2005). The types of methods used in their study related to my study. One method they
used was to have participants’ record how they rinsed and what other types of oral
hygiene they performed during the study. I asked my subjects to keep track of their oral
hygiene activities during my experiment. Menendez et al.’s (2005) methods also assisted
in evaluating types of error that may occur during the study by being able to see if a
variable besides the mouthwash was affecting the levels of oral bacteria.
Fine et al. (2000) demonstrated that antimicrobial agents can have anti-plaque
activities. If proper daily oral hygiene is not performed, oral bacteria can lead to
gingivitis, the inflammation of the gums (Brown, 2005). Fine et al. (2000) determined the
effect of rinsing twice daily with an essential oil-containing antiseptic mouth rinse,
Listerine®, on the levels of recoverable S. mutans in the saliva. Twenty-nine subjects
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were randomly assigned to use either oil-containing rinse or water as a control. The
subjects rinsed with 20 mL for 30 seconds twice daily for 11 days and once on the 12th
day, in addition to using their normal daily hygiene tools (Fine et al., 2000). On the 12th
day, Fine et al. (2000) collected and analyzed saliva and plaque samples. This procedure
was then repeated on day 19 after the subjects had not used any rinsing products for one
week. The authors reported that Listerine® reduced S. mutans levels in plaque by 69.9%
on day 12, 75.4% on day 19, 50.8% on day 12, 39.2% on day 19 in saliva (Fine et al.,
2000). Therefore, they recommend that patients, whose mechanical oral hygiene
techniques were not adequate, should use an antimicrobial mouth rinse to reduce plaque
levels (Fine et al., 2000). The methods used by the Fine et al. (2000) study recommended
how many times subjects should rinse each day and how many times subjects’ plaque and
saliva samples should be recorded. This helped me to decide when and how many times I
would need to collect samples from my subjects, which I did on day 1 and on day 14.
My study examined the effect of different oral rinses on oral bacteria. I tested
whether individuals who rinse with 10 mL of ACT® fluoride once a day for fourteen
days will have less bacteria levels in their mouth than those who rinse with 30 mL of
Crest® mouthwash or a water control, for the same duration. These volumes were chosen
because they are the recommended dosages specified on the labels. These particular
rinses were chosen because ACT® is the most commonly used fluoride rinse and Crest®
is a commonly used alcohol free rinse (Arweiler et al., 2003). My subjects were
randomly divided into three equal groups of 15 subjects per group, one group for each
rinse. I used a sterile swab to sample each person’s mouth to determine the beginning
levels of bacteria. A swab consisted of a right and a left swab, three swipes on each side,
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making sure to wipe the same part of the cheek cells inside the mouth on every person.
The subjects were instructed to rinse twice daily for 30 seconds with the specified rinse
for 14 days. I took a final oral swab on day 14 to determine whether oral bacteria levels
had decreased. I measured optical density as an indirect measure of bacterial levels and
used an Analysis of Variance test (ANOVA) to analyze the data. After conducting an
ANOVA test, I compared the mean bacterial levels with a Tukey multiple comparisons
test. I also measured the zones of inhibition that resulted from a water control, Crest®
mouthwash, and ACT® fluoride on S. mutans grown on the surface of nutrient agar. The
zone of inhibition data were analyzed with a two-factor Analysis of Variance (ANOVA)
test using mouth rinse and incubation time. Based on findings from these literature
reviews, I hypothesized that rinsing once a day for 30 seconds with 10 mL of ACT®
fluoride for fourteen days will reduce more oral microbial growth than rinsing with 30
mL of Crest® mouthwash.
Methods:
The level of antimicrobial properties of different mouth rinses was measured in
two ways: with human subjects and in the laboratory. I measured the subjects’ oral
bacteria samples with a spectrophotometer and analyzed the effectiveness of the mouth
rinses on prepared S. mutans by testing the zone of inhibition in the laboratory.
Recruiting participants:
I recruited 45 Saint Martin’s University students who signed an Institutional
Review Board (IRB) form to consent to participate in this study. Previous studies such as
Menendez et al. (2005) and Arweiler et al. (2003) had their subjects have a professional
tooth cleaning prior to their studies. I did not require this of my subjects, due to financial
constraints. There were also no requirements for selection to participate in this study;
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therefore no one was excluded based on gender, race, or particular oral hygiene. The 45
individuals were randomly divided into three equal groups, 15 people per group: using
either ACT© fluoride rinse, Crest© mouthwash, or a control (blue, mint flavored water).
A similar study by Brecx et al., (1990) divided their study groups in the same fashion.
My subjects were instructed to carry on their daily oral hygiene activities during the study.
Optical Density Experiment of Oral Bacteria:
Preparing tryptic soy broth:
I prepared Ward’s Natural Science tryptic soy broth by using 8g of nutrient
powder for every 1 L of distilled water. I produced a solution by mixing 1.5 grams of
broth powder with 50 mL of distilled water. The mixture was slightly stirred, heated, put
into test tubes, and then the mixture was placed in a Tuttnauer 2540E autoclave machine
at 121º C and 15 pounds per square inch (psi) for 15 minutes. Once it was autoclaved, the
test tubes were capped tightly and placed into the refrigerator until the following day
when the tubes were inoculated with S. mutans. A second set of 100 test tubes were
made on February 15, 2007 that were used to incubate the oral samples taken from the
participants. The oral swab samples were placed in the test tubes filled with tryptic soy
broth and incubated at 37º C for a total of 48 hours. Observations were recorded at 24 and
48 hours, by taking the human oral samples and processing those through a
spectrophotometer to get measurements based on the amount of light that is passed
through the sample producing an absorbance reading on the machine.
Inoculating Streptococcus mutans:
From a previously made stock culture of S. mutans purchased from Ward’s
Natural Science, I inoculated my own culture to work from. According to Brown (2005),
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I heated an inoculating loop to sterilize and then let it cool prior to inserting it into the
stock culture. Then I shook the stock culture with the bacteria, flamed the opening of the
tube, and took a loop full of organisms from the tube and inserted it into a tube of sterile
broth. Then I removed the loop from the broth, flamed the mouth of the tube, and capped
the tube. I finally inserted my cultured bacteria into an incubator at 37º C and for
approximately 72 hours to cultivate the bacteria.
Organizing oral rinses for participants:
In my study I focused on two active ingredients. They were sodium fluoride
(0.05%) and cetylpyridinium chloride (0.07%). Both of these active ingredients are in the
ACT® fluoride rinse, however only the cetylpyridinium chloride (0.07%) is in the
Crest® mouthwash. I took 45 plastic bottles and prepared them to hand out to my
subjects. In the first 15 bottles I added a total of 330 mL of Crest© mouthwash to each
bottle, in the second set of 15 bottles I added 180 mL of ACT© fluoride rinse, and in the
final set of 15 bottles I used 180 mL of mint tasting, blue water for a control. To mix the
control, I added approximately 3-4 drops of blue food dye per 0.5 L of water. Along with
the dye, I also added 5-7 drops of mint extract per 1 L of the control. The water control
had mint extract and blue dye in order to run a blind study, so my subjects did not know
what rinse they were using. Finally, each bottle was labeled with an alpha-numerical code
and distributed to a participant.
Samples taken from human subjects:
Within the three groups of mouth rinses, I took an initial swab of each mouth
using a sterilized cotton swab. While I took samples from my participants, I wore safety
equipment that included protective goggles and plastic gloves. A sample consisted of a
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right and a left swab, three swipes on each side, making sure to wipe the same part of the
cheek cells inside the mouth on every person. The swabs were placed into the prepared
tubes filled with Ward’s Natural Science tryptic soy broth and were incubated at 37º C
and for 24 hours. Following the incubation, the samples were placed into a
Spectronic20D+ spectrophotometer to be analyzed. Then, the subjects were instructed to
continue their daily hygiene activities including rinsing with 10 or 20 mL of the specified
rinse once daily for 30 seconds. The amounts that the participants were told to use was
based on the daily recommended dosages provided on the mouth rinse bottle labels. The
participants were given a calibrated rinse cup with the specified rinse amount marked.
Every subject was given a chart for them to record their daily hygiene activities and
directions on how to use their specific rinse. Subjects were instructed to bring their rinse
back to me on the final day, Day 14. I wanted my subjects to bring their rinse back to me
to see if they were actually rinsing during the 14 day testing period and I recorded how
much of the rinse each subject used during the experiment. On Day 14, following sterile
procedures, I took another swab of the subject’s cheek cells and placed the swab into a
test tube with nutrient broth to be incubated at 37º C and for 24 hours, and bacterial
growth was then measured by a spectrophotometer.
Optical density tests:
Optical density was measured using a Spectronic20D+ spectrophotometer. As
light passes through a culture within the spectrophotometer, light will be absorbed by the
cells. The amount of light absorbed is proportional to the concentration of cells (Brown,
2005). I measured the amount of light that was absorbed by the cells. To do this, I
transferred tryptic soy broth with the bacteria culture to disposable cuvettes, which were
9
then placed into the spectrophotometer. First, a blank of the control, which was
autoclaved tryptic soy broth with no sample, was used to calibrate the machine. Finally, I
recorded the optical density of the individual oral samples to determine the specific
mouth rinses’ ability to inhibit oral bacteria.
Zone of Inhibition Experiment of Oral Bacteria:
Preparing nutrient agar:
Agar plates were used in the zone of inhibition studies. The type of agar that was
used in my study was Ward’s tryptic soy agar. Ward (1993) recommended using this agar
to ensure optimal growth of S. mutans flourishes best on this agar. According to Brown
(2005), to prepare an agar plate, 2g of agar powder to 25mL of distilled water solution
was needed to be mixed. I mixed a total of 600 mL of liquid agar into a beaker. The
mixture was boiled for 1 minute, cooled to 55º C, and then placed into an autoclave. Once
it was autoclaved, at 121º C and 15 psi for approximately 15 minutes, I poured the
autoclaved agar into 50 sterilized Petri plates and the plates were left to cool and solidify
for approximately two hours. After the plates had solidified, I placed them in the
refrigerator, upside down to keep moisture from contaminating the agar.
Re-hydration of cultures:
According to Ward’s Natural Science (1993), I grew the S. mutans first by
removing the inner cryovial and added 0.5 mL of liquid media with a sterile pipette. Once
the bacteria pellet had softened, I mixed the media up and down 8-10 times using a sterile
pipette. Then I dipped a sterile cotton swab once into the bacteria, soaked it, and streaked
it onto an agar slant (Ward’s Natural Science, 1993). The remaining bacteria was pipetted
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into a broth tube and put into an incubator at 37º C for approximately 72 hours to develop
and was used for zone of inhibition testing.
Zone of inhibition test:
The zone of inhibition on the growth of the agar plates was defined by where the
location of the visible growth had been inhibited (Brown, 2005). First, the agar was
inoculated with S. mutans by streaking the bacteria across the agar plate. A semisaturated disk that had been dipped half way with sterilized tweezers into one of the three
mouth rinse treatments, including the water control, was placed into a quadrant of the
agar plate. The disks were 5 mm in diameter and were soaked in the specified rinse for 30
seconds. This time period was chosen because that is the length of time the human
subjects will be rinsing. I placed four filter paper disks on each Petri plate and there were
a total of 14 plates per treatment, for a total of 56 filters per treatment. The plates were
left to incubate for 48 hours at 37º C. Observations were recorded throughout incubation
at 24 and 48 hours and the zone of inhibition was measured and recorded at each
observation interval. The diameter of the zone of inhibition was recorded in millimeters
(mm). Due to the zones of inhibition being oblong shaped, I took three different
diameters of each zone and averaged them, in order to get an accurate measurement.
Table 1 illustrates the numerical components of this experiment.
Table 1. Data concerning the number of replicates per treatment for each corresponding mouth rinse, as
well as the total number for the entire study. Each plate contained four filters.
ACT Fluoride
Crest Mouthwash
Control Rinse
Total
24 hours
14
14
14
42
48 hours
14
14
14
42
11
Total
28
28
28
84
Total: 168
Statistical tests: ANOVA/ multiple comparisons test
An Analysis of Variance (ANOVA) test was used to determine whether
the observed differences among the sample means was due to chance, or was it
supporting evidence for a difference among the means (Mobre and McCabe, 1993). The
treatments for the ANOVA from the optical density test were the three different mouth
rinses. However, the factors for the two-factor ANOVA from the zone of inhibition test
were the three different rinses and incubation times. If significant differences between the
treatments were found using the ANOVA tests, I conducted Tukey multiple comparisons
tests to compare individual treatments to one another. The ANOVA and Tukey multiple
comparisons test were calculated and analyzed using Minitab, Inc (2005).
Results:
Results were obtained from two kinds of tests: with optical density and zones of
inhibition. Optical density readings were taken prior to the subjects using the rinse (prerinse) at 24 and 48 hour intervals and after the subjects used the rinse (post-rinse) at 24
and 48 hour intervals. I used an ANOVA test to compare the optical density values of
samples from the three rinse groups and found no significant difference among
antibacterial effectiveness of ACT©, Crest©, or the control at 24 hours pre-rinse (F= 0.65,
d.f.= 2, p= 0.527) and 24 hour post-rinse (F= 0.22, d.f.= 2, p= 0.801). At the 48 hours
pre-rinse (F=0.35, d.f.= 2, p= 0.708) and post-rinse (F= 0.32, d.f= 2, p= 0.726) there was
also no significant difference among the treatments. However, after testing the oral
samples within each rinse, there was a significant difference in the pre and posttreatments for each mouth rinse ACT (F= 8.73, d.f.=1, p=0.006), Crest (F= 13.26, d.f.=1,
p=0.001), and the control (F= 6.57, d.f.=1, p= 0.016). The ACT© mouth rinse had a
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larger average decrease in bacteria than the Crest© and control when comparing the pre
and post-treatments and is shown in Figure 1. The results from the Tukey comparison test,
with an individual confidence level (ICL) of 95%, indicated that ACT© and Crest© were
Absorbance
not significantly different from the control.
2.00
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0.00
ACT
Crest
Control
Mouthrinses
Pre-treatment @ 24 hours
Post-treatment @ 24 hours
Figure 1. Absorbance of cultures after 24 hour incubation at 37°C. Forty-five individuals were randomly
divided into three equal groups, 15 people per group: using either ACT© fluoride rinse, Crest© mouthwash,
or a control (blue, mint flavored water). This figure shows the three types of mouth rinses and their mean
absorbance measured at 686 nm at the pretreatment 24 hour observations and the post treatment 24 hour
observations. Pre-treatment is a sample taken prior to using a mouth rinse and post-treatment is a sample
taken 14 days after using a mouth rinse. The error bars represent one standard error about the mean.
The optical density values were also measured after incubation at 48 hours for
both the pretreatment and post treatment within each mouth rinse (Figure 2). Pretreatment is a sample taken prior to using a mouth rinse and post-treatment is a sample
taken 14 days after using a mouth rinse.
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Absorbance
2.00
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0.00
ACT
Crest
Control
Mouthrinses
Pre-treatment @ 48 hours
Post-treatment @ 48 hours
Figure 2. Absorbance of cultures after 24 hour incubation at 37°C. Forty-five individuals were randomly
divided into three equal groups, 15 people per group: using either ACT© fluoride rinse, Crest© mouthwash,
or a control (blue, mint flavored water). This figure shows the three types of mouth rinses and their mean
absorbance measured at 686 nm at the pretreatment 48 hour observations and the post treatment 48 hour
observations. Pre-treatment is a sample taken prior to using a mouth rinse and post-treatment is a sample
taken 14 days after using a mouth rinse. The error bars represent one standard error about the mean.
For the zones of inhibition, I tested a total of 14 plates per treatment, and each
plate had 4 quadrants each with one filter disc. After 24 hours, each plate was measured
using a metric ruler and the average zone of inhibition around each quadrant’s filter of
each plate was recorded (Table 2).
The data were analyzed using an ANOVA test, which showed no statistical
difference between the two mouth rinses (F=0.00, d.f.=1, p=0.961). However, when the
control’s results were compared with the ACT© and Crest© mouth rinses, there was a
significant difference between each rinse and the control (F= 291.12, d.f. = 2, p= 0.0005).
The results from a Tukey multiple comparisons test, with an individual confidence level
(ICL) of 95%, indicated that ACT© and Crest© were significantly different from the
control. The Crest© mouth rinse resulted in a greater zone of bacteria inhibition than the
ACT© mouth rinse with an average of 12.39 mm (Figure 3).
14
Millimeters (mm)
19.0
17.0
15.0
13.0
11.0
9.0
7.0
5.0
3.0
1.0
ACT @ 24 hours
Crest @ 24 hours
Zone observations @ 24 hours
Figure 3. The average zones of inhibitions, measured in millimeters, for each mouth rinse. Filter discs were
dipped and applied to a plate on which S. mutans had been previously spread. Plates were then incubated at
37°C for 24 and 48 hours. Data concerning the average diameter in millimeters (mm) for each treatment for
each corresponding mouth rinse at 24 and 48 hour intervals. The ACT fluoride had an average zone
diameter of 12.36 mm and the Crest mouthwash had an average zone diameter of 12.39 mm after 24 hours.
There was no change in the average diameter after 24 hours. The control rinse was also tested and had a
value of 0 mm within each zone. The plates were also analyzed at 48 hours and there was no change from
the 24 hour observations. The error bars represent one standard error about the mean.
Discussion:
The current short term research examined the antibacterial effectiveness of ACT©
fluoride rinse, Crest© mouthwash, and a control. The results obtained in this study failed
to show a difference among the mouth rinses. Each test comparing the absorbance levels
of oral bacteria before and after the rinse treatment showed no significant difference
(p=0.801) for the oral samples that were incubated for 24 hours or the oral samples that
were incubated for 48 hours among the three mouth rinses (p=0.726) (Figures 1& 2).
However, after comparing absorbance values within each individual mouth rinse, the
absorbance levels suggested there was a decrease among the bacterial levels after using
the rinses. The reason for this could be attributed to the active ingredients within the
ACT© and Crest© mouth rinses. Also, the bacterial levels of the group using the control
rinse decreased. This could be credited to the mint extract that was added for flavor
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purposes to the control rinse. The mint extract has a small concentration of alcohol,
which is found in some mouth rinses and could be a reason for the decrease in bacterial
levels. A reason for not seeing a significant difference among the rinses could also be
accredited to an insufficient sample size. Further tests specifically analyzing these mouth
rinses could be more effective if the sample size was increased to the hundreds.
Within the zone of inhibition tests, there was no significant difference (p=0.961)
when comparing the inhibited growth on the ACT© and Crest© Petri plates (Figure 3).
However, when each individual rinse was compared to the control plates, both the ACT©
and Crest© mouth rinses had a significant difference for ACT© (p= 0.0005) and Crest©
(p= 0.0005) among the inhibited growth. The smallest zone of inhibition achieved by
either rinse was 6 mm by both the ACT© and Crest© mouth rinse and the largest zone of
inhibition achieved by either rinse was 28 mm by the Crest© mouth rinse. This difference
between the zones of inhibitions suggests that the tested mouth rinses illustrate signs of a
wide range of antibacterial effectiveness. The reason for this could be attributed to the
different active ingredients in each mouth rinse and the variability of bacterial levels in
people’s mouths. For future testing, one could focus on a specific active ingredient and
test how sufficiently the active ingredients inhibit the bacterial growth.
The specific difference between the ACT© and Crest© mouth rinses was the
sodium fluoride active ingredient found in ACT©. Sodium fluoride has demonstrated
antimicrobial effectiveness suggested by Moran and Addy (1988). Even though the
ACT© mouth rinse contained this active ingredient, the results obtained by my study
failed to support Lee’s (2004) hypothesis that fluoride is an essential ingredient in mouth
rinses, which is also common in some toothpastes. Arguments made by Moran and Addy
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(1988) supporting the existence of fluoride in mouth rinse would benefit future studies by
specifically looking at particular mouth rinses that contained sodium fluoride as its active
ingredient and then comparing it to other active ingredients such as alcohol, glycerin, or
cetylpyridinium chloride.
This study only included one of the many bacteria present in the oral cavity, S.
mutans. Further studies of mouth rinses could also include other common types of oral
bacteria such as Lactobacillus and Staphylococcus aureus (Leyster, 2006). Future tests
could include a variety of oral bacteria, as well as various active ingredients such as
chlorhexidine, hydrogen peroxide, amine fluoride, and triclosan.
Furthermore, a collection of factors, including participants using different oral
hygiene procedures, or even the participants not following the instructions they were
given regarding the usage of the rinses, could attribute to the discrepancies that were
displayed in this study. Even though the mouth rinses demonstrated affirmative inhibition,
other factors as described by Leyster (2006) include the oral cavity’s environment,
practiced oral care, and the composition of a diet, and how they ultimately play a role
with the outcome of antibacterial effectiveness.
Many individuals use a mouth rinse for various reasons: reducing bacteria, bad
breath, etc. A mouthwash is a solution used as an addition to regular oral hygiene
methods, like brushing and flossing. It helps to prevent plaque formation as well as to
treat certain specific conditions like gum infections, bad breath, and ulcers. However,
brushing your teeth is necessary and not replaceable by mouthwashes. Physical plaque
control remains the most important goal in the prevention of dental diseases and
maintenance of oral health. Therefore, dental health is an important aspect of general
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health care. A regular visit to the dentist is vital for maintaining a good oral health.
Brushing your teeth twice daily, flossing, using mouthwash and eating a balanced diet are
some of the essentials for having the perfect dental health.
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Acknowledgements:
I would like to take this opportunity to express my gratitude towards Saint
Martin's University Professors Mary Jo Hartman and Margaret Olney for their assistance
during my research. They provided problem solving techniques in regards to my research
performed at the University. In addition, I would like to thank Cheryl Guglielmo for her
assistance with the materials that were necessary for my research. I would like to show
appreciation to Chelsi Claussen and my fellow Senior Seminar classmates for their
support throughout the year. Finally, I would like to thank the SMU community for
participating in my research
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Meridol®, and chlorohexidine mouth rinses on plaque, gingivitis and plaque
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Brown, A.E. 2005.Benson’s Microbiological Applications, ninth ed. McGraw Hill Ed.,
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Fine, D.H., Furgang, D., Barnett, M.L., Drew, C., Charles, C.H., Vincent, J.W. 2000.
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