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Reduction in bacterial contamination of toothbrushes using the Violight ultraviolet light activated toothbrush sanitizer


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This two armed, self-controlled, investigator blinded, clinical study tested the efficacy of an ultraviolet (UV) light toothbrush holder (Violight) to decrease toothbrush bacterial contamination. 25 subjects were randomly assigned to control or experimental groups and received two toothbrushes for home use on either even or odd days. The control group rinsed both toothbrushes after use in cold tap water with no mechanical manipulation. The experimental group rinsed one toothbrush in cold running water while storing the other toothbrush in the Violight toothbrush holder after use. The toothbrushes were returned after 2 weeks use in sealed plastic bags and were analyzed for the number of colony forming units (CFU) of S. mutans, S. salivarius, lactobacilli, E. coli, and other coliforms, and total bacterial counts by culture. An additional analysis of the total bacterial profile was performed using denaturing gradient gel electrophoresis (DGGE). The Violight toothbrush holder reduced total CFU by an average of 86% (ANCOVA, P = 0.037). In addition, a tendency was noted for a reduction in total bacterial population as detected by DGGE.
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Research Article
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Reduction in bacterial contamination of toothbrushes using the Violight
ultraviolet light activated toothbrush sanitizer
ABSTRACT: Purpose: This two armed, self-controlled, investigator blinded, clinical study tested the efficacy of an
ultraviolet (UV) light toothbrush holder (Violight) to decrease toothbrush bacterial contamination. Methods: 25 subjects
were randomly assigned to control or experimental groups and received two toothbrushes for home use on either even or
odd days. The control group rinsed both toothbrushes after use in cold tap water with no mechanical manipulation. The
experimental group rinsed one toothbrush in cold running water while storing the other toothbrush in the Violight
toothbrush holder after use. The toothbrushes were returned after 2 weeks use in sealed plastic bags and were analyzed for
the number of colony forming units (CFU) of S. mutans,S. salivarius, lactobacilli, E. coli, and other coliforms, and total
bacterial counts by culture. An additional analysis of the total bacterial profile was performed using denaturing gradient gel
electrophoresis (DGGE). Results: The Violight toothbrush holder reduced total CFU by an average of 86% (ANCOVA,
P= 0.037). In addition, a tendency was noted for a reduction in total bacterial population as detected by DGGE. (Am J Dent
CLINICAL SIGNIFICANCE: These results suggest that the Violight toothbrush holder can decrease bacterial contamination
of toothbrushes between uses.
: Dr. Jane McCutcheon, Department of Basic Sciences and Craniofacial Biology, New York University College of
Dentistry, Mail Code 9436, 345 East 24th Street, New York, New York 10010-4086, USA. E-:
The uninterrupted accumulation of oral bacterial plaque is
strongly associated with an increased risk for dental caries, the
development of gingivitis and the promotion of oral malodor.1-3
Mechanical disruption of bacterial plaque through the use of
toothbrushes, or a combination of toothbrushing, interproximal
hygiene procedures and use of oral mouth rinses has been
regarded as an optimal means of preventing plaque accumula-
tion and the promotion of overall oral health. However, bacteria
remain on the toothbrush after use and may provide a potential
source for recontamination of the oral cavity on the next use.
One study4 has reported a bacteremia due to a viridans strepto-
cocci (S. oralis) strain that was cultured from the patient’s oral
cavity and from the subject’s toothbrush suggesting that
colonization of toothbrushes with oral microflora may be
associated with bacteremia in some patients. Environmental
enteric bacterial contamination of toothbrushes resulting from
bathroom aerosols has also been reported5,6 which may also
contaminate faucets, combs and hairbrushes.7
Several bactericidal agents have been promoted to reduce
the possibility of toothbrush bacterial contamination between
uses. These include the use of chlorhexidine,8 Brushtox,9 and
several dentifrices.10-12 While all of the above have shown
varying degrees of efficacy, none are widely used as a home
based application. A possible reason for non-compliance with
these methods is they are time consuming and may result in
unwanted product residues.
Ultraviolet (UV) light is bactericidal to a wide array of
bacterial species including antibiotic resistant species13-15 and
has been extensively used in water purification systems.
Violighta (Fig. 1) is a toothbrush holder that uses UV light for
bacterial decontamination. The toothbrush is inserted into the
device and a button is pressed to deliver a 10-minute UV
irradiation dose. The design of the Violight toothbrush holder
prevents exposure to UV light when in use. Due to its ease of
use, Violight may increase compliance in toothbrush bacterial
decontamination. However, the extent of bacterial decon-
tamination using the Violight toothbrush holder has not been
determined in a clinical setting. Therefore, the objective of the
present investigator-blinded, self-controlled, clinical study was
to determine the efficacy of Violight in decreasing toothbrush
bacterial contamination.
Materials and Methods
Subject recruitment and study design - The study design was
reviewed and approved by the New York University School of
Medicine Institutional Board of Research Associates. Subjects
were recruited from the patient pool seeking dental care at the
New York University College of Dentistry and from advertise-
ments in local media. Inclusion criteria included subjects be ≥
18 years of age, in good general health, able to give informed
consent and comply with the study protocol, have at least 10
natural teeth per arch, and brush their teeth twice daily.
Exclusion criteria included the clinical evidence of gross caries
or periodontal disease, the presence of systemic diseases or
conditions that would affect the oral cavity such as uncontrolled
diabetes mellitus, use of any medications associated with
xerostomia or any antibiotic therapy within 7 days prior to the
start of the study protocol.
Subjects were randomly assigned to either the control or the
experimental groups. Each subject was provided with two
toothbrushes of different color (green and silver) for home use
on either odd or even days. The control group was instructed to
rinse both brushes after use in cold running water without any
mechanical manipulation. The experimental group was instruct-
ed to rinse one brush (green) in running water without mechani-
cal manipulation and treat the second toothbrush (silver) with
314 Boylan et al
Fig. 1. Violight toothbrush holder storing toothbrushes. The device can be used
store toothbrushes after the treatment cycle is completed. to
the Violight toothbrush holder (Fig. 1) after every use. The
treated brush was stored in the Violight toothbrush holder
between uses in the subject’s room at home where they
typically brush their teeth (i.e. typically their bathroom).
Subjects were instructed to start the study the evening after
enrollment and to follow their regular oral hygiene regimen.
Subjects returned the first toothbrush in a pre-labeled sealed
plastic bag on day 13 of the study and the second toothbrush in
a pre-labeled sealed plastic bag on day 14 of the study.
Toothbrushes were returned to the Bluestone Center for
Clinical Research within 1 hour after use in the morning. The
toothbrushes were promptly delivered to the laboratory for
bacterial extraction and cultivation (see below). After
xtraction, the toothbrushes were stored at -20 ºC. e
Bacterial culture - Methods used for bacterial culture followed
standard techniques.16 Media used for bacterial culture were
purchased from Difcob unless otherwise noted. Media included
Trypticase Soy Agarc for total counts, Mitis salivarius agarc for
total streptococci, Mitis salivarius agar with 2 IU/ml of
bacitracinc for mutans streptococci, MacConkey agar with 1%
lactosec for E. coli and other coliforms, and Rogosa SL agarc
or lactobacilli. f
For bacterial extraction, the toothbrushes were individually
placed in pre-labeled, sterile 50 ml centrifuge tubes containing 10
ml of trypticase soy brothc (TSB) to immerse the bristles, then
vortexed vigorously for 1 minute, squeezed against the side of
the tube to drain, rinsed with 5 ml TSB and drained again. A
series of undiluted and 10-fold dilutions of each sample were
prepared and plated onto the surface of selective and non-
selective media. A duplicate series of plates was then incubated
aerobically or anaerobically at 37°C for 2-4 days, until colony
formation was visible. The number of colonies, measured as
olony forming units (CFU), was counted using a colony counter. c
Polymerase chain reaction (PCR) and denaturing gradient gel
American Journal of Dentistry, Vol. 21, No . 5, October, 2008
electrophoresis (DGGE) assays - PCR and DGGE assays were
used to identify both cultivable and non-cultivable bacteria
present on four pairs of randomly selected toothbrushes from
the 25 pairs of clinical samples. The toothbrushes were washed
by agitation in 5.0 mL of phosphate-buffered saline (PBS) and
centrifuged at 126,800 x g. for 30 minutes. The supernatant was
discarded and the cell pellet was re-suspended in 0.5 ml TE
buffer (10 mM Tris-Cl, pH 7.5, and 1 mM EDTA). The total
bacterial genomic DNA was isolated by means of a DNA
purification kit (MasterPured) with modifications as previously
A nested-PCR approach was used to first amplify the entire
1500-bp 16S-rRNA locus for all extracted bacterial DNA sam-
ples with a set of universal 16S rRNA PCR primers19 followed
by a second amplification of a hyper-variable region (~300 bp)
of the 16S-rRNA locus.19 In the first PCR, each 50 μL reaction
mixture contained a standardized 100 ng of the total genomic
DNA, 200 μM of each dNTP, 50 pmole of universal primers
16S-8f and 16S-1492r (19), 1.5 mM MgCl2, 5 L of 10X PCR
buffer II, and 2.5 U of Taq DNA polymerase.e In the second
PCR, a specific set of universal bacterial 16S rRNA primers
(prbac1 and prbac2)20 was used with a 40-nucleotide GC-clamp
to facilitate the DGGE analysis.21-23 All PCR procedures were
performed with the GeneAmp PCR System 9700.e PCR condi-
ions and reagents were as described elsewhere.17,18 t
A standardized 20 μL of each PCR-amplified product was
separated on gradient gels as previously described.17,18 A 40% to
60% linear DNA denaturing gradient was formed in an 8%
(w/v) polyacrylamide gel. PCR products were directly loaded in
each lane and were run along with known species-specific
DGGE reference markers.17 After electrophoresis, the gels were
rinsed and stained for 15 minutes in 0.5 g/mL ethidium bro-
mide. The DGGE images were digitally captured and recorded.f
The DNA fingerprints of the DGGE were compared and
analyzed by means of Fingerprinting II Informatixg software as
reviously described.17,18 p
Statistical analysis - Data were entered and checked into a
password-protected data set and analyzed using SPSS for
Windowsh (Version 13). All bacterial counts were log
transformed to normalize their distributions prior to analysis.
An ANCOVA was performed to compare the differences in
bacterial levels between the control and treatment groups using
as a covariate the log of the total bacterial count on the first
(cold water rinsed) toothbrush. The ANCOVA was adjusted for
the individual specific CFU counts in the untreated situation
and compared the second untreated toothbrush in the control
group to the treated (Violight) toothbrush in the treatment
group. The differences in total and each specific bacterial
counts were also expressed as a percent reduction in CFUs
comparing the Violight treated brush to the untreated, cold
water rinse brush. Group characteristics were compared by
Mann-Whitney-Wilcoxon test for continuous variables and
Fisher’s exact test for categorical measures. A value of P< 0.05
as accepted for statistical significance. w
Twenty five subjects (20 females, five males) aged 21-65
years (28 ± 10; mean ± standard deviation of the mean) were en-
rolled in this study consisting of seven Caucasians, 10 African-
American Journal of Dentsitry, Vol. 21, No . 5, October, 2008
Fig. 2. Changes in CFU of bacterial levels on the paired toothbrushes for each
subject. Each pair of circles connected by a line represents one subject. The left
hand group represents the control subjects and the right hand group represents the
treatment subjects whose second day toothbrush received Violight treatment.
Seven of the 10 treatment subjects show reductions in CFU for the toothbrush
eated with the Violight as compared to toothbrushes treated with cold water. tr
Violight & toothbrush bacteria 315
Table 1. Descriptive statistics for log CFU.
Adjusted value
Toothbrush #1 Toothbrush #2 Toothbrush #2
__________________ ___________________ _____________________
Group N Mean SD Mean SD Mean SD
ontrol 12 4.99 1.25 4.88 0.85 4.89 0.75
Treatment 10 5.02 1.18 4.17 0.86 4.17 0.75
Statistics for the two toothbrushes in each treatment group and for toothbrush 2
adjusted for the log CFU values on Toothbrush 1 based on an ANCOVA.
Toothbrush 1 was always a cold water rinse brush (regardless of group).
Toothbrush 2 was cold water rinsed in the control group and Violight treated in the
treatment group. The data are for log transformed CFU’s. Visually looking at the
difference in mean values, there was little difference in brush 1 and 2 in the control
roup but a reduction in the treatment group. g
Table 2. ANCOVA. Total CFU.
Type III sum Mean
Source of squares df square F P value
Baseline 4.008 1 4.008 7.155 0.015
roup 2.822 1 2.822 5.038 0.037
Error 10.643 19 0.560
The dependent variable was the log CFU on Toothbrush 2. The independent factor
oup and the covariate was the log CFU on Toothbrush 1 (a baseline value). was gr
Fig. 3. Comparison of DGGE profiles between the controls (A) and experimental toothbrushes (B). The pair-
wise similarity was 95% for the controls, suggesting no changes in bacterial population between the two
samples. The similarity was 60.0% for the experimental pair, indicating a 40% reduction in the bacterial
population after Violight treatment.
Americans, four Hispanics, two Asians and one other ethnic
group. One subject failed to return and was excluded from the
final data analysis. The control and treatment groups were
balanced for age (P= 0.295), ethnicity (P= 0.805), and gender
(P= 0.332).
Twenty-four of the 25 subjects were able to return their
toothbrushes on day 13 and 14 in sealed labeled bags as
instructed. Bacteria were extracted from the toothbrushes and
used to determine CFU or for DGGE analysis. Streptococcus
mutans was cultured from only two subject’s toothbrushes and
lactobacilli were cultured from only one subject’s toothbrush,
therefore no further analyses were performed for these two
species. Log transformation of E. coli and S. salivarius and
subsequent ANCOVA analysis revealed no statistically
significant differences between the experimental and control
groups (F= 1.05, df= 1, P= 0.32). However, an 86% reduction
in the CFU of the total bacterial counts was observed between
the Violight and control groups. An approximate 10-fold mean
reduction from 104,713 to 14,791 CFU was observed in the
Violight treated group (Table 1). ANCOVA was used to adjust
for the individual specific CFU counts in the untreated situation
compared between the second untreated toothbrush in the
control group to the treated (Violight) toothbrush in the experi-
mental group. As reported in Table 2, there was a statistically
significant difference (F= 5.04, df= 1, P= 0.037) in the log CFU
of the total bacterial counts between the control and experi-
316 Boylan et al
mental groups. Finally, a comparison of the difference between
the toothbrushes for both the control and experimental groups
was determined for each individual. The results in Fig. 2 show
that the number of bacterial counts on the treated toothbrushes
decreased in the experimental group compared to that in the
control group.
To further determine the efficiency of the above bacterial
extraction method and the Violight treatment, a pair of
toothbrushes were analyzed using DGGE. No bacterial DNA
samples were detectable by PCR after extraction for culture,
suggesting the extraction procedure was highly efficient. A
second two pairs of toothbrushes from two subjects in the
control group were directly examined for bacterial population
profile using DGGE without cultivation. The comparison was
conducted between the toothbrushes before and after regular
water rinsing, and the two bacterial profiles obtained were
found to be highly similar (94.6% concordance) (Fig. 3). A
third pair of toothbrushes was obtained from a subject in the
experimental group. The bacterial profile analysis showed that
the similarity was only 60% (Fig. 3) suggesting a reduction in
bacterial contamination may occur after using the Violight
toothbrush holder.
The paired toothbrush design used in this study was
developed to determine if the Violight toothbrush holder can
reduce the bacterial load remaining on toothbrushes after use.
This study, using both conventional bacterial culture methods
and more sensitive PCR-based non-culture methods, demon-
strates that the Violight group had an average reduction of 86%
in the bacterial load (Fig. 2, left side, Fig. 3 bottom). This
finding was further supported by an approximate 40% decrease
n bacterial population by the DGGE analysis. i
Decreasing the total bacterial load in the oral cavity, as well
as decreasing specific bacterial species, is a fundamental
therapeutic approach designed to decrease the incidence and
severity of gingival inflammation, caries and oral malodor.
Although few studies have examined whether bacteria trans-
ferred to a toothbrush can be a source for oral re-colonization,
studies have shown that bacteria from the oral cavity and other
sources can be found on toothbrushes and use of various
chemical products can decrease the bacterial load on the
toothbrush.9-12 Despite evidence demonstrating that chemical
rinses and dentifrices can reduce the total bacteria load on a
toothbrush, these methods are not widely in use. Possible
reasons for poor compliance include ease of use, the need for
additional procedures after brushing or unwanted product
residues. The results of this study suggest that a UV light
toothbrush holder can effectively reduce by an average of 86%
total cultivatable bacteria on a toothbrush. This result was
supported by the DNA-based DGGE technique. Since the
device requires no additional input from the subject other than
pushing a button to activate the device, it is possible that the
ease of use of the Violight toothbrush holder will increase
patient compliance while reducing between use bacterial load
n toothbrushes. o
It is important to note the limitations of the present study.
First, bacterial culture demonstrated that one subject had an
American Journal of Dentsitry, Vol. 21, No . 5, October, 2008
increase in the total cultivatable bacteria with the Violight
treated toothbrush compared to the untreated toothbrush (Fig.
2). One possibility for this anomalous result could be that the
subject had poor compliance in treating the toothbrush with
Violight toothbrush holder prior to delivering it to the
laboratory. Although subjects were asked if there were any
problems using the Violight toothbrush holder, the study design
did not include a questionnaire or any other means to evaluate
that the treated toothbrush was indeed treated before being
returned for bacterial analysis. Second, as S. mutans and
lactobacilli are associated with caries initiation and progression,
we were interested to determine the effect of the Violight
toothbrush holder on these species. However, this study
observed low detection rates for both S. mutans and lactobacilli.
However, both species are known to have low retention rates on
oothbrushes.24,25 t
E. coli is not generally considered to be a common resident
of the oral cavity, yet it and other common enteric bacteria have
been found in the oral cavity by other studies.26,27 The presence
of E. coli is more common in patients with periodontal disease,
but not exclusively so.26 E. coli and other enteric bacteria are
found as pathogens in elderly subjects with hospital acquired
pneumonia.27 Despite some association with disease, it is
important to remember that many strains of E. coli are
avirulent, so that the mere presence of these bacteria may not
ecessarily be an indicator of disease. n
Finally, reducing the bacterial load and population in the
oral cavity is generally thought to be beneficial to oral health
by reducing caries, gingivitis and oral malodor, as well as
promoting general health. Yet, data in support of this
contention are limited.4 While this study demonstrates that the
Violight toothbrush holder reduces both the bacterial load and
overall population on toothbrushes, this result should not be
extrapolated to conclusions about the effect of the Violight
toothbrush holder on oral or general health. Further clinical
studies will be required to determine the effect of reduction of
toothbrush bacterial load and diversity on oral and general
a. Violight Inc., Elmsford, NY, USA.
b. Difco, Detroit, Michigan, USA.
c. Sigma, St. Louis, MO, USA.
d. Epicenter, Madison, WI, USA.
e. PE Applied Biosystems, Foster, CA, USA.
f. Alpha Innotech Corporation, San Leandro, CA, USA.
g. Bio-Rad Laboratories Inc., Hercules, CA, USA.
h. SPSS, Chicago, IL, USA.
Acknowledgements: To Dr. Robert Norman (Director of Biostatistics and Data
Management, Bluestone Center for Clinical Research, NYU) for
statistical analysis, Dr. Zhou Chen for technical support, the research
coordinators of the Bluestone Center for Clinical Research and the research
subjects, all of whom helped make this study possible. This study was funded in
part by Violight Inc., Elmsford, NY, USA.
Dr. Boylan is Associate Professor, and Dr. Li is Associate Professor,
Department of Basic Sciences and Craniofacial Biology, Dr. Simeonova is
researcher/trainer, Department of Reconstructive and Comprehensive Care, and
Dr. Sherwin is Clinical Assistant Professor, Department of Cariology and
Comprehensive Care; Ms. Kreismann is Clinical Associate Professor, Dental
Hygiene Program, Dr. Craig is Associate Professor, Department of Basic
Sciences and Craniofacial Biology and Department of Periodontology and
Implant Dentistry, Dr. Ship (deceased) was Professor, Department of Oral &
Maxillofacial Pathology, Radiology, and Medicine and Director, Bluestone
American Journal of Dentsitry, Vol. 21, No . 5, October, 2008
Center for Clinical Research; Dr. McCutcheon is Associate Professor,
Department of Basic Sciences and Craniofacial Biology and Bluestone Center
for Clinical Research, New York University College of Dentistry, New York,
ew York, USA. N
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... Shows characteristics of all the included studies. The number of RCTs included for this review 2,17,[22][23][24][25][26][27] were carried out between the year 2007 and 2016. Amongst the included studies, five were conducted in India, two in Turkey and one from New York. ...
... Sanitization was carried out by placing the brush in the receptacle and the head of the toothbrush was exposed for 12 minutes to UV radiation. Toothbrushes in the microwave group were sanitized by placing the brush in a microwave oven (2450MHz) for 5 minutes. 2 Other study carried out by Boylan et al., 22 showed sanitization via the use of UV light holder. Meta-analysis illustrated that the use of both ultra-violet rays and microwave had significant effect on reduction of the microbial count of the used toothbrush with a mean difference of -2.61 and CI (-4.66,-0.76) ...
Full-text available
Toothbrushes play an essential role in personal oral hygiene by effective plaque removal.However, they get heavily contaminated by bacteria, viruses, yeasts, and fungi which may originate from the oral cavity after every use as well as from the environment where they are stored. This systematic review was conducted to identify various decontamination interventions attempted scientifically and it summarizes the efficacy of each. Meta-analysis illustrated that the use of Ultra-violet rays and Microwave had a significant effect on reduction of the microbial count of a used toothbrush with a mean difference of -2.61 and CI (-4.66,-0.76) with I2=98%. When compared with non-active treatment group, the natural agents (garlic, green tree and tea-tree oil) proved to sterilize the toothbrushes effectively with mean difference of -483.34, CI (-914.79, -51.88) and I2=100%.In contrast, chlorhexidine showed the insignificant result with a mean difference of -347.55 and CI (-951.90, 256.80) with I2=100%. The evidence from this review suggests that decontaminating toothbrush reduces bacterial load. Toothbrushes exposed to radiation and natural agents proved to sanitize them effectively but chlorhexidine rendered insignificant results. Keywords: Chemical agent; disinfection; radiation; microbial load; natural agent; toothbrus
... [11] In a meta-analysis with eight randomized controlled trials, natural agents were found to be effective in decreasing the microbial colonization of toothbrush bristles. [7,9,10,[12][13][14][15][16][17] Polyphenolic compounds in herbal products are accountable for their anti-Streptococcus mutans property, which inhibits the glucosyltransferase enzyme activity of S. mutans. [12,18,19] With due consideration to available evidence pertaining to side effects and emergence of uncommon infections with the usage of synthetic antimicrobial agents and the fact that resistance to currently used chemotherapeutics is the major factor that necessitates the search for alternative safe, efficacious, and cost-effective treatment options, particularly in developing countries. ...
Aims: The aim of this study was to evaluate the efficacy of 0.2% chlorhexidine and 4% tulsi extract as toothbrush decontaminants. Materials and methods: Of 100 children, who attended the outpatient unit of Department of Pediatric dentistry, 81 children, who satisfied all the inclusion criteria were subjected to systematic sampling, after arranging them in the alphabetical order and were grouped into three. The first child came under Group I, second under Group II, third under Group III, fourth one again under Group I, and so on till the 81st child. In the baseline phase, the children were provided precoded toothbrushes and toothpastes and instructed to place those brushes to be put after use, in single-use glasses. After obtaining the baseline value of Streptococcus mutans colony count, the participants of Group I was given 0.2% chlorhexidine, Group II was given 4% tulsi extract, and distilled water for Group III, to be used as toothbrush decontaminants for 5 days. The toothbrushes were then collected back, and were subjected to microbial analysis. Statistical analysis was performed by using Kruskal-Wallis one-way analysis of variance (ANOVA) and Mann-Whitney U test with P < 0.05. Results: All test solutions, 0.2% chlorhexidine and 4% tulsi extract, except for distilled water, showed a statistically significant reduction of S. mutans count. There was no statistical difference between the efficacies of 4% tulsi extract and 0.2% chlorhexidine, although the latter showed a better reduction. Conclusion: Tulsi extract may well be a perfect replacement to chlorhexidine for reducing the S. mutans count in the child toothbrushes.
... bacteremia can be induced by tooth brushing, increasing the potential risk of transmission, which may be exacerbated in people with gingivitis and periodontitis (6) .The colonization of these pathogenic micro-organisms on toothbrush while being stored in unsanitary conditions represents a potential cause of recontamination of the oral cavity (7) .The tooth brush may get contaminated by Streptococcus, Staphylococcus, and lactobacilli (8) . These bacteria are implicated in the causation of many life threatening diseases such as infective endocarditis besides influencing the occurrence of oral diseases such as dental caries and gingivitis (7)(8)(9) . The toothbrushes are often preserved in bathrooms which are a good place to harbor millions of different pathogenic micro-organisms. ...
... [19] In our study, the toothbrushes were collected from study participants after 14 days. Many studies have chosen different study intervals such as 48 h, [20] 5 days, [21,22] 7 days, [23,24] and 3 months. [25] In our study, we have taken 14 days because a study conducted by Sogi et al. [20,22] states that maximum microbial contamination was found in toothbrushes after 14 and 28 days. ...
Introduction: A toothbrush is the most common oral hygiene aid used, but maintaining and storing the toothbrush hygienically is commonly neglected. In India, people are not aware of the contamination of toothbrushes. Contaminated toothbrushes can act as a vector for the transmission or reinfection of various bacteria, viruses, and fungi. The herbs, which have pharmaceutical properties, can be used as an alternative. The study aimed to compare the antimicrobial efficacy of 3% neem and 3% garlic on Streptococcus mutans and to compare with 0.2% chlorhexidine mouthwash as toothbrush decontaminants. Materials and Methods: A triple-blinded randomized controlled trial was done on 120 subjects. The subjects were divided into four groups: Group I (distilled water), i.e., control, three study groups having 3% neem (Group II), 3% garlic extract (Group III), and 0.2% chlorhexidine gluconate (Group IV). Subjects were provided toothbrushes and toothpaste for both baseline and intervention phases. The toothbrushes were collected after 14 and 28 days for microbial analysis in both phases. The data were analyzed and compared using appropriate t-test and analysis of variance. The level of significance was set at P < 0.05. Results: Garlic (Group III) was most effective at 98%, followed by chlorhexidine (Group IV) 96% and neem (Group II) 88% in reducing the level of S. mutans. Distilled water (Group I) showed only a 3% reduction. Conclusion: Neem and garlic proved to be as effective as chlorhexidine, and these herbal products can be used as an alternative to chlorhexidine as disinfectants for toothbrushes. These are the common ingredients that can be easily found in Indian households. It is herbal, cost-effective, and has no side effects so it can be easily used by every individual as a toothbrush decontaminant.
... Soaking toothbrushes in an antibacterial mouth rinse (chlorhexidine [5], HiOra (The Himalaya Drug Company, Bangalore, India), or 3% neem) after use has also been studied and a significant decrease in bacterial contamination was observed [6][7]. Recent advancements, such as an ultraviolet (UV) light toothbrush holder (Violight, VIOlight Inc., NY, US), reduce the total colony-forming units by an average of 86% [8], soaking brushes in an ozone-saturated phosphate-buffered saline (PBS) solution was shown to be an effective alternative after a 30-minute exposure [9]. Mouthwash contains active ingredients that act as a decontaminant for toothbrushes, thereby serving as an economical and accessible solution for toothbrush decontamination. ...
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Background Toothbrushes are the most commonly used mechanical plaque control methods, and they are said to harbor microorganisms if not stored properly following usage. Objective An assessment of the influence of a decontaminating agent (sterile water (control)/chlorhexidine mouthwash/herbal mouthwash) on the properties of toothbrush bristles following storage for 24 hrs by means of scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Methodology The study involves a total of 24 slim soft toothbrushes (six samples per group) with different decontaminating agents: Group 1: Vented container, Group 2: Sterile water, Group 3: 0.2% Chlorhexidine mouthwash, and Group 4: Herbal mouthwash. The toothbrushes were stored in their respective containers for 24 hours, following which, snippets of toothbrush bristles were collected and tested for the evaluation of wear using SEM and the biochemical alteration occurring in the bristles was assessed using FTIR. Results and conclusion The Group 2 and Group 3 samples showed significant wear (Score 2) under SEM evaluation, and FTIR spectroscopy evaluation revealed that changes occur in the fingerprint region of infrared spectroscopy owing to chemical bond alteration following decontamination. Considering the benefits we acquire in terms of microbial load reduction, decontamination is recommended, though it might necessitate frequent changing of toothbrushes.
... Грибы рода Can- dida, коринебактерии, псевдомонады и энтеробактерии были идентифиированы в 70, 60, 50 и 30% случаев со- ответственно. Авторами ранее не было установлено за- висимости количества и состава микробной контами- нации зубных щеток от условий их хранения [7]. ...
AIM: To evaluate microbial contamination of toothbrushes and the efficacy of different oral disinfectant agents in their decontamination METHODS: The heads of 98 used toothbrushes derived from patients who needed oral hygiene treatment were included in the study. In the laboratory, microorganisms on toothbrush heads were identified using standard microbiological methods. Toothbrush heads with microorganisms were then randomly divided into four groups of 19 and disinfected with Brushtox, Andolex C, Listerine® and water (control), followed by microbiological analysis RESULTS: Seventy eight percent of toothbrushes were contaminated with different microorganisms. Coagulase-negative staphylococci (CoNS) were found in a high number of toothbrushes (49%), followed by Pseudomonas spp (37%), Staphylococcus aureus (32%), Streptococcus mutans (14%), coliforms (9%) and Candida albicans (3%). Decontamination of toothbrushes with Andolex C and Listerine® reduced the number of contaminated toothbrushes by 74% each, Brushtox by 90% and water by 0.0% CONCLUSION: Toothbrushes were contaminated with various types of microorganisms, but predominantly with CoNS. Although Brushtox is a toothbrush spray, soaking toothbrushes in this solution was the most effective method, reducing the number of disinfected toothbrushes by 90%. Oral health practitioners should raise awareness to their patients regarding the need to disinfect toothbrushes
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Schwannoma is a benign nerve sheath tumour that origi- nates from schwann cells of the peripheral nerve. In spite of constituting 25-40% of head and neck tumours its in- traoral presentation is rare which accounts for only 1%. The purpose of this case report is to highlight the rarity of this lesion, to emphasize the significance of an accurate diagnosis and to include tumours of nerve sheath origin in the differential diagnosis of facial asymmetry.
Background Charcoal toothbrushes have been marketed widely claiming lesser bacterial contamination owing to the presence of activated charcoal. Aim and Objective The aim of this study was to evaluate the bacterial contamination and antimicrobial efficacy of charcoal bristles compared to noncharcoal bristles in used toothbrushes. Materials and Methods A total of 50 patients met inclusion criteria which were given standard brushing instructions on the use of a charcoal toothbrush and were asked to return the used brushes after 1 week of usage. After a washout period of 1-week, the participants were then provided with noncharcoal toothbrush and given similar brushing instructions to both groups and were instructed to return the brush after another week of usage. Bristles of the used toothbrushes were sectioned and placed in a 5 ml of saline, and 0.1 ml was inoculated on blood agar plates, which were then placed in a gas pack jar for anaerobic culture. Colony forming units (CFU) were measured after 48 h of incubation. To evaluate the antibacterial efficacy of charcoal bristles, the zone of inhibition was evaluated for charcoal versus noncharcoal after 24 h of incubation. Data collected were analyzed using a paired sample t-test. Results The mean CFU count for noncharcoal bristles was almost double that of charcoal bristles. About 10 mm of the zone of inhibition was found around charcoal bristles as compared to 3 mm for noncharcoal bristles. Conclusion This study shows the statistically significant difference in bacterial counts between bristle types and lower CFUs in the charcoal bristles compared with noncharcoal bristles, after 1 week of use. The zone of inhibition that was found around charcoal tooth bristles supported the antimicrobial properties of the charcoal toothbrush.
The transmission of bacteria in biofilms from donor to receiver surfaces precedes the formation of biofilms in many applications. Biofilm transmission is different from bacterial adhesion, because it involves biofilm compression in between two surfaces, followed by a separation force leading to the detachment of the biofilm from the donor surface and subsequent adhesion to the receiver surface. Therewith, the transmission depends on a balance between donor and receiver surface properties and the cohesiveness of the biofilm itself. Here, we compare bacterial transmission from biofilms of an extracellular-polymeric-substance (EPS)-producing and a non-EPS-producing staphylococcal strain and a dual-species oral biofilm from smooth silicon (Si) donor surfaces to smooth and nanopillared Si receiver surfaces. Biofilms were fully covering the donor surface before transmission. However, after transmission, the biofilms only partly covered the donor and receiver surfaces regardless of nanopillaring, indicating bacterial transmission through adhesive failure at the interface between biofilms and donor surfaces as well as through cohesive failure in the biofilms. The numbers of bacteria per unit volume in EPS-producing staphylococcal biofilms before transmission were 2-fold smaller than in biofilms of the non-EPS-producing strain and of dual species. This difference increased after transmission in the biofilm left behind on the donor surfaces due to an increased bacterial density for the non-EPS-producing strain and a dual-species biofilm. This suggests that biofilms of the non-EPS-producing strain and dual species remained compressed after transmission, while biofilms of the EPS-producing strain were induced to produce more EPS during transmission and relaxed toward their initial state after transmission due to the viscoelasticity conferred to the biofilm by its EPS.
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Poor dental hygiene has been linked to respiratory pathogen colonization in residents of long-term care facilities. We sought to investigate the association between dental plaque (DP) colonization and lower respiratory tract infection in hospitalized institutionalized elders using molecular genotyping. We assessed the dental status of 49 critically ill residents of long-term care facilities requiring intensive care treatment. Plaque index scores and quantitative cultures of DPs were obtained on ICU admission. Protected BAL (PBAL) was performed on 14 patients who developed hospital-acquired pneumonia (HAP). Respiratory pathogens recovered from the PBAL fluid were compared genetically to those isolated from DPs by pulsed-field gel electrophoresis. Twenty-eight subjects (57%) had colonization of their DPs with aerobic pathogens. Staphylococcus aureus (45%) accounted for the majority of the isolates, followed by enteric Gram-negative bacilli (42%) and Pseudomonas aeruginosa (13%). The etiology of HAP was documented in 10 patients. Of the 13 isolates recovered from PBAL fluid, nine respiratory pathogens matched genetically those recovered from the corresponding DPs of eight patients. These findings suggest that aerobic respiratory pathogens colonizing DPs may be an important reservoir for HAP in institutionalized elders. Future studies are needed to delineate whether daily oral hygiene in hospitalized elderly would reduce the risk of nosocomial pneumonia in this frail population.
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We describe a new molecular approach to analyzing the genetic diversity of complex microbial populations. This technique is based on the separation of polymerase chain reaction-amplified fragments of genes coding for 16S rRNA, all the same length, by denaturing gradient gel electrophoresis (DGGE). DGGE analysis of different microbial communities demonstrated the presence of up to 10 distinguishable bands in the separation pattern, which were most likely derived from as many different species constituting these populations, and thereby generated a DGGE profile of the populations. We showed that it is possible to identify constituents which represent only 1% of the total population. With an oligonucleotide probe specific for the V3 region of 16S rRNA of sulfate-reducing bacteria, particular DNA fragments from some of the microbial populations could be identified by hybridization analysis. Analysis of the genomic DNA from a bacterial biofilm grown under aerobic conditions suggests that sulfate-reducing bacteria, despite their anaerobicity, were present in this environment. The results we obtained demonstrate that this technique will contribute to our understanding of the genetic diversity of uncharacterized microbial populations.
Background, aims: Previous studies indicated that oral hygiene aids can play a rôle in the intra-oral translocation of pathogens. The survival rate of cariogenic and periodontopathogenic species on toothbrushes, with and without toothpaste, and interdental brushes was presently investigated.Material and methods: 12 periodontitis patients had their interdental spaces professionally cleaned with interdental brushes and their teeth with new toothbrushes with or without different dentifrices. Each time brushes were rinsed with tap water and stored dry at room temperature. At different time intervals an interdental brush or 4 tufts from a toothbrush were processed for vitality staining and selective and non-selective culturing procedures.Results: Immediately after rinsing, a toothbrush without toothpaste harboured 107, 108 and 107 colony forming units (CFU) of respectively aerobic, anaerobic and black pigmented species. An insignificant decrease occurred the first 24 hours and after 48 hours still 104 CFU of aerobic and anaerobic species could be cultured. No periodontopathogen remained detectable at 8 hours, except for Fusobacterium nucleatum. The proportion of vital bacteria decreased in 48 hours from 50% to 30%. Comparable results were obtained for interdental brushes. The bacterial survival rate on toothbrushes was significantly reduced by the use of a detergent containing toothpaste by 2 log at baseline, another 2 log at 4 hours and an extra log more at 8 hours for aerobic and anaerobic species. A toothpaste without detergent only had an insignificant bactericidal effect.Conclusion: Toothpaste detergents decrease the survival rate of pathogenic species on a toothbrush and can thus limit the risk for bacterial translocation.ZusammenfassungGrundlagen, Ziele: Frühere Studien haben gezeigt, dass Mundhygienehilfsmittel auch eine Rolle bei der intraoralen Übertragung von Pathogenen spielen können. Die Überlebensrate von kariogenen und parodontalpathogenen Spezies auf Zahnbürsten, mit oder ohne Zahnpasta, und Interdentalbürsten wurde gegenwrtig untersucht.Material und Methoden: Bei zwölf Patienten mit Parodontitis wurden ihre Interdentalrume professionell mit Interdentalbürsten und ihre Zhne mit neuen Zahnbürsten unter Verwendung von Zahnpasta oder ohne Zahnpasta gereinigt. Jedes mal wurden die Bürsten unter Leitungswasser gespült und bei Trocknen bei Raumtemperatur aufbewahrt. Zu unterschiedlichen Zeitintervallen wurde eine Interdentalbürste oder 4 Borsten einer Zahnbürste zur Vitalfrbung sowie der selektiven und nichtselektiven Kultivierung weiterverarbeitet.Ergebnisse: Direkt nach den Spülen weißt eine Zahnbürste ohne Zahnpasta 107, 108 und 107 Koloniebildende Einheiten (CFU) von aeroben, anaeroben bzw. schwarzpigmentierten Spezies auf. In den ersten 24 Stunden ergab sich eine nicht-signifikante Abnahme und nach 48 Stunden konnten immer noch 104 CFU von aeroben und anaeroben Spezies kultiviert werden. Kein Parodontalpathogen, außer Fusobacterium nucleatum war nach 8 Stunden noch nachweisbar. Der Anteil an lebenden Bakterien nahm in 48 Stunden von 50% auf 30% ab. Mit den Interdentalbürsten wurden vergleichbare Ergebnisse erzielt. Die Uberlebensrate von Bakterien auf Zahnbürsten wurde durch die Verwendung einer Zahnpasta, die ein Detergenz enthlt, signikant reduziert. Direkt nach dem Putzen wurden die aeroben und anaeroben Spezies mit 2 log, nach 4 Stunden abermals 2 log und eine weiterer log nach 8 Stunden reduziert. Eine Zahnpasta ohne Detergenz hatte nur einen nicht-signifikanten bakteriziden Effekt.Schlussfolgerung: Detergenzien der Zahnpasta vermindern die Überlebensrate von pathogenen Spezies auf einer Zahnbürste und können daher das Risiko für eine Übertragung von Bakterien begrenzen.RésuméOrigine, but: Des études préalables indiquent que les accessoires d’hygiène orale pourraient jouer un rôle dans la translocation intra-orale des pathogènes. Le taux de survie des espèces cariogènes et parodontopathogénes sur les brosses à dents, avec ou sans dentifrice, et sur les brossettes interdentaires a été recherché dans cette étude.Matériaux et méthodes: Chez 12 patients atteints de parodontite, les espaces interdentaires ont été nettoyés de façon professionnelle avec des brossettes interdentaires et les dents ont été brossées aved une brosse neuve avec ou sans dentifrice. A chaque fois, les brosses étaient rincées avec l’eau du robinet et séchées à température ambiante. A différents intervals, une brossette ou 4 touffes d’une brosse étaient examinées par coloration de la vitalité et des méthodes de culture sélectives et non sélectives.Résultats: Immédiatement après le rinçage, une brosse à dents sans dentifrice présentait respectivement 107, 108, et 107 unités formant colonie (CFU) d’espèces aérobiques, anaérobiques et à pigmentation noire. Une diminution insignifiante survenait dans les premières 24 h, et après 48 h, il était encore possible de cultiver 104 CFU d’espèces aérobiques et anaérobiques. Aucun pathogène parodontal n’était détectable à 8 h, sauf Fusobacterium nucleatum. La proportion de bactéries vivantes diminuait de 50 à 30% en 48 h. Des résultats comparables étaient obtenus avec les brossettes interdentaires. Le taux de survie des bactéries sur les brosses était significativement réduit par l’utilisation d’un dentifrice contenant un détergent, de l’ordre de 2 log initialement, à nouveau 2 log à 4 h et encore un log supplémentaire à 8 h pour les espèces aérobiques et anaérobiques. Un dentifrice sans détergent n’avait qu’un effet bactéricide insignifiant.Conclusions: Les détergents des dentifrices diminuent le taux de survie des espèces pathogènes sur les brosses à dents et peuvent ainsi limiter les risques de tranlocation bactérienne.
Large numbers of bacteria and viruses when seeded into household toilets were shown to remain in the bowl after flushing, and even continual flushing could not remove a persistent fraction. This was found to be due to the adsorption of the organsims to the porcelain surfaces of the bowl, with gradual elution occuring after each flush. Droplets produced by flushing toilets were found to harbor both bacteria and viruses which had been seeded. The detection of bacteria and firuses falling out onto surfaces in bathrooms after flushing indicated that they remain airborne long enough to settle on surfaces throughout the bathroom. Thus, there is a possibility that a person may acquire an infection from an aerosol produced by a toilet.
Studies were designed to evaluate the effectiveness of pulsed modulated UV light waveforms for killing bacteria. Exposure of five strains of bacteria to the modulated information encoded in the light decreased the colony population from a confluent lawn to less than 20 colonies. However, approximately 2,000 colonies survived treatment with the same intensity and time of exposure to UV light lacking the modulated information.
Denaturing gradient gel electrophoresis (DGGE) can be used to distinguish two DNA molecules that differ by as little as a single-base substitution. This method detects approximately 50% of all possible single-base changes in DNA fragments ranging from 50 to approximately 1000 base pairs. To increase the number of single-base changes that can be distinguished by DGGE, we used the polymerase chain reaction to attach a 40-base-pair G + C-rich sequence, designated a GC-clamp, to one end of amplified DNA fragments that encompass regions of the mouse and human beta-globin genes. We show that this GC-clamp allows the detection of mutations, including the hemoglobin sickle (HbS) and hemoglobin C (HbC) mutations within the human beta-globin gene, that were previously indistinguishable by DGGE. In addition to providing an easy way to attach a GC-clamp to genomic DNA fragments, the polymerase chain reaction technique greatly increases the sensitivity of DGGE. With this approach, DNA fragments derived from less than 5 ng of human genomic DNA can be detected by ethidium bromide staining of the gel, obviating the need for radioactive probes. These improvements extend the applicability of DGGE for the detection of polymorphisms and mutations in genomic and cloned DNA.
Group A streptococcal strains of some serotypes can be cultured repeatedly from normal human skin for days or weeks and subsequently produce pyoderma, but strains of other serotypes that cause pharyngitis are rarely recovered from normal human skin or skin lesions. In an attempt to understand the biological differences between "skin" and "throat" strains of group A streptococci, we studied their susceptibility to two bactericidal agents operative at the skin surface--oleic acid and UV light. No consistent differences were found between skin and throat strains; all streptococcal strains were exquisitely sensitive to both oleic acid (10 microgram/ml) and UV light (60 microW/cm2).