This document describes an in vitro study that evaluated the antimicrobial activity and properties of a tissue conditioner containing silver nanoparticles. The study tested the antimicrobial effects of the tissue conditioner with 0-3% silver nanoparticles against common oral microbes like C. albicans, S. mutans, and S. aureus. The results found that 0.1% silver nanoparticles had a minimal bactericidal effect against S. aureus and S. mutans, while 0.5% had an effect against C. albicans. Control samples showed no inhibition. The study concluded the material could be an effective antimicrobial dental material, but further mechanical and toxicity testing is required.

1. NAMITHA AP
2ndYEAR MDS
J Adv Prosthodont 2011;3:20-4
Ki-Young Nam

2.  INTRODUCTION
 AIM
 MATERIALSAND METHODS
 RESULTS
 DISCUSSION
 RELATED ARTICLES
 CONCLUSION
 REFERENCES

3. Silver nano
particles
Antimicrobial
low toxicity
profile
Rapid and
Broad
spectrum
activity
well
tolerated
tissue
response
Maintenance of
tissue conditioner
Mechanical and
chemical methods
Systemic or local
antibiotic agents
Microbial
resistance!!

4. Silver
containing
materials
Central
venous
catheter
Wound
dressing
Vascular graft
Bone
cements
Endotracheal
tubes
Coating in
dental
implants
• Sustained silver cation release
• More effective than microsized

6.  identify in vitro antimicrobial activity of the tissue conditioner
containing silver nanoparticles on microbial strains
• fungal species associated
with denture stomatitisCandida albicans
• oral endogenous bacteriaStreptococcus
mutans
• nosocomial respiratory
infection-causing bacteria
Staphylococcus
aureus

7. Aqueous silver sol was prepared with 10.0 mM
of analytical grade AgNO3 in distilled water
• 2.0% PVP (Polyvinyl Pyrrolidon) was used as stabilizer.
All solutions were deaerated by bubbling with
argon gas for 1 hour
then they were irradiated in the field of 20 KGy
60Co Gamma-ray sources

8. Samples were placed on separate culture plate dish
containing 0.1 - 3.0% (vol)silver nanoparticles
0 0.1 0.5 1 2 3
Experimental disc samples (20.0×3.0 mm) of tissue conditioner (GC
Soft-Liner, GC cooperation,Tokyo, Japan)

10. antimicrobial effects of samples were evaluated as a percentage of
viable cells in withdrawn suspension (100 μL)
Microbial growth was verified
At 24 hours At 72 hours
microbial suspensions (100 μL) of tested strains were inoculated then
incubated at 37℃.

11. • grown in brainheart infusion
(BHI) (Difco, Franklin Lakes,
NJ, USA) broth and onto
Mueller Hinton agar plates
at 37℃
BACTERIAL
STRAINS
• grown in Schaedler broth
(Difco, Franklin Lakes, NJ
,USA) and onto Sabouraud
agar plates (Difco, Franklin
Lakes, NJ, USA) at 30℃.
FUNGAL
STRAINS

12. After incubating microbial cells at 37℃
overnight, optical density (OD) of the
suspension at 600 nm was adjusted to
1.0 using a spectrophotometer (Milton
Roy spectrophotometer 20D+, Milton
Roy, Ivyland, USA).
The suspension was diluted with
phosphate-buffered saline (pH 7.4)
to 1:100 and suspended to final
concentration of 1.0 × 107
cells/mL.14,21

13. Each disc sample of Ag�-tissue conditioner and control were
placed on the flat bottom of the separate 12-well cell culture
plate(Costa�,Corning, NewYork, USA) of 22.1 mm well diameter
100 μL of initial microbial suspensions in 1.0 ml of Sabouraud
broth were inoculated to each well and incubated at 37℃.
After incubation for 24 hrs and 72 hrs for extended contact period,
suspension (100 μL) was withdrawn

14. borderline of the antimicrobial effect was determined at 0.1% viable cells.

15. • 0.1% silver nanoparticles
combined to tissue conditioner
minimal bactericidal effect
against Staphylococcus
aureus and Streptococcus
mutans strains
• 0.5%silver nanoparticles
combined to tissue conditioner
Minimal bactericidal effect
against candida albicans
• Control group
No microbial inhibitory
effect

16.  Optimal concentration of silver?
 Toxic effects of silver?
 Effect of addition of nanoparticles on other
properties of material
 In vivo studies?

17.  Within the limitation of this in vitro study, the
results suggest that the tissue conditioner
containing silver nanoparticles could be an
antimicrobial dental material in denture
plaque control. Further mechanical stability
and toxicity studies are still required.

18. KishoreGinjupalli
TusharShaw
ChaitanyaTellapragada
RamakrishnaAlla
LokendraGupta
RELATEDARTICLES 1
J Dent Mater 2018

19.  to evaluate the antimicrobial
activity and properties of
irreversible hydrocolloid
impression material
incorporated with silver
nanoparticles of varying size at
different concentrations
80-100
nm
50-80
nm
30-50
nm
10-20
nm
.5
1
2
5
Wt
%
E coli
Candida
albicans
Staphylococcus
aureus
Strains used

20. • Kirby Baurs disc diffusion method
Measurement of anti
microbial activity
• Allowed to contact a polished PMMA rod
• Loss of adherence noted
Measurement of
gelation time
• Loaded to disposable syringe injected onto glass slab within 60s
• Another glass plate put on mix and a weight of 14.7 N was placed on top glass
plate for 5s
• Measure min and max diameter of disc formed and expressed in mm
Measurement of flow
• Stressing the specimen at 6 mins from beginning of mixing using universal
testing machine
Measurement of gel
strength
• Subjected to 10% strain for 15 s in universal testing machine
• Load removed and allowed to recover for 30s
Measurement of
permanent
deformation

21. Prepared irreversible hydrocolloid specimens were sliced
into 3 mm thickness using sterile BP blade
placed in lawn cultures prepared on Muller Hinton agar
plates using respective bacterial or yeast suspensions
matching to turbidity of 0.5 Mc Farland’s standerd
Cultureplates incubated for 24 hrs.zones of inhibition in
millimeters were measured

23.  Silver nanoparticles of 80–100 nm size have
imparted superior antimicrobial activity to the
irreversible hydrocolloid in a dose-dependent
manner
 finer nanoparticle size did not exhibit any
antimicrobial activity.
 The addition of silver nanoparticles did not alter
the properties of irreversible hydrocolloid at 0.5
and 1.0 wt% whereas at higher concentrations
significant differences in flow, gelation time and
strength were observed.

24.  The results of the present study indicate that
silver nanoparticles of size range 80–100 nm
are superior in imparting antimicrobial
activity to irreversible hydrocolloid compared
to finer particle size range.

25. Related articles 2
J Prosthet Dent 2015

26.  aim  Materials and methods
 The antimicrobial activity and
properties of 2 commercially
available irreversible hydrocolloid
impression materials were evaluated
after incorporating varying concen-
trations of silver nanoparticles.
Antimicrobial activity was
determined using the disk diffusion
method. The gel strength,
permanent deformation, flow, and
gelation time were measured
according to American Dental
Association specification #18.
 The purpose of this
in vitro study was
to investigate the
antimicrobial activity
and properties of
irreversible
hydrocolloid
impression materials
incorporated with
silver nanoparticles.


27. a dust-free
alginate
(Zelgan
Plus;
Dentsply
India Pvt
Ltd)
color-
changing
alginate
(Tropicalgin;
Zhermack
SpA).

silver nanoparticles
(Nano Labs) of 80
to 100 nm in size
were added to
these irreversible
hydrocolloids, and
their properties
were evaluated.
.5wt%
1wt%
2wt%
5wt%

30.  Adding silver nanoparticles to irreversible hydrocolloid
impression materials resulted in superior antimicrobial activity
without adversely affecting their properties.
 Adding silver nano- particles to Zelgan significantly increased the
gel strength compared with the control group, except at 5 wt%.
However, the gel strength ofTropicalgin was unaffected except at
5 wt%.
 An increase in the permanent deformation was found with the
incorporation of silver nanoparticles in both Zelgan and
Tropicalgin.
 The flow of Zelgan increased with the incorporation of silver
nanoparticles, whereas a decrease in the flow ofTropicalgin was
observed at 1 wt% and 2 wt%. An increase in the gelation time of
both Zelgan and Tropicalgin was observed with the
incorporation of silver nanoparticles.

31. GrzegorzChladek , Anna Mertas , Izabela Barszczewska-
Rybarek ,Teresa Nalewajek , Jarosław Żmudzki ,Wojciech Król
and Jan Łukaszczyk
RELATEDARTICLES 3
Int. J. Mol. Sci. 2011

32.  They presented a method of incorporating
AgNPs into the chemically cured silicone soft
liner material UfiGel SC (UG).The aim of this
work was also to evaluate the antifungal
efficacy of these developed composites.

33.  The modification
process was conducted
by dissolving both
material components
(base and catalyst) in a
colloidal solution of
AgNPs and
evaporating the
solvent.
10 ppm 20 ppm
40 ppm 80 ppm
120 ppm 200 ppm

34. Measurements using dynamic light scattering (DLS) for colloidal solutions of 30
ppmAgNPs showed an average NP size of 22.8 nm.
when the AgNP concentration increased, the color of the samples became darker.
Int. J. Mol. Sci. 2011, 12

35. Scanning electron microscopy measurements show the presence of both individual particles
(Figure 3) and large nanoparticle agglomerates in the modified soft liners. Individual particles
from all specimens usually ranged from 10 to 30 nm. In the case of a higher AgNP
concentration, a greater number of nanoparticle aggregations and larger sized aggregations
were observed. Starting with a concentration of 80 ppm, numerous large agglomerates were
noted. Most of them ranged between 100 and 300 nm, but there were also huge aggregations
that exceeded 1 μm, and individual AgNPs were still observed.

37.  For material specimens without AgNPs, the observed
Candida albicans CFU/mL value increased by 23.4%
compared with the positive control.The introduction
of 10 ppm AgNPs to the polymer led to an antifungal
efficacy (AFE) of 16.4%. Increasing theAgNP
concentration in the composite to 20 ppm resulted in
an additional increase in the AFE of 8%.The average
AFE value for samples with 40 ppm AgNPs was 31.5%.
An additional increase in theAgNP concentration
resulted in a less dynamic, but still visible, AFE
increase. For the highest examinedAgNP
concentration (200 ppm), the maximum composite
AFE value reached was 52.2%.

38.  In this study, they presented a method ofAgNP
incorporation into chemically cured silicone soft
liner materials.
 The AFE of the achieved composites containing
10 to 200 ppm AgPNs was 16.3% to 52.5%.
 This level of AFE should be capable of
preventing colonisation of Candida albicans on
soft denture linings.
 Future research should examine the mechanical
characteristics of the achieved composites and
confirm their microbiological characteristics in in
vivo studies.

39. Wenjuan Liu, Bin LiuˆYuanyuan Qi
RELATEDARTICLES 4
International conference on biomedical engineering and biotechnology-
2012

40.  In this study, they
investigated the
appropriate adding ratio of
the LZB-GC nano silver-
filled antibacterial agent in
the alginate impression
material.
 antibacterial agent may
affect the physical
properties of the
impression material.
PHYSICAL PROPERTIES
 coagulation time
 compressive strength
 compressive strain
 deformation restorability
 fluidity of the alginate
impression material by
adding different content of
LZB-GC antibacterial agent
were characterized by
standards method

41. PROPORTIONS OF LZB GC
ANTIBACTERIAL AGENT ADDED
0.25 .5
1 1.5
2 2.5
STRAINS USED
Staphylococcus
auresus
E coli
Their antibacterial activities were tested
by Film adhesion method
The antibacterial
ratios were
assessed
according to the
national standard
"Antimicrobial
plastics-Test for
antimicrobial
activity and
efficacy"

42. To evaluate the physical
properties measurement
indicators are shown inTable 1
is used

43.  The antibacterial ratios increased as the
content of LZB-GC increased.
 content of LZB-GC increased from 0.125% to
0.5%, the antibacterial ratios of Escherichia
coli and Staphylococcus aureus all increased
 when the content of LZB-GC was 0.5% or
more, the antibacterial ratios could be up to
99%.

44. • coagulation time, deformation restorability
compressive strain, compressive strength
and fluidity of all the experimental groups
compared with control group had no
statistically significant difference
content of
antibacterial agent
was less than 2%
• only compressive strain had statistically
significant differencecontent of
antibacterial agent
was 2%
• coagulation time, compressive strain and
compressive strength had statistically
significant difference
content of
antibacterial agent
was more than 2%

45.  It was indicated that the optimal adding ratio of
the LZB-GC antibacterial agent in the alginate
impression material was 0.5%, which could
provide the experimental evidence and
theoretical basis for its clinical application. In
summary, the self-disinfection method of the
alginate impression material is feasible. Whether
the adding of LZB-GC nano-silver antibacterial
agent having effects on the biocompatibility of
the alginate impression material deserves to be
explored in further study

46. 1. Kaur P, Luthra R. Silver nanoparticles indentistry: An
emerging trend. SRM J Res Dent Sci 2016;7:162-5.
2. Silver nanoparticle incorporation effect on mechanical
and thermal properties of denture base acrylic resins, J
Appl Oral Sci. 2016;2,
3.Ginjupalli K, et al. Does the size matter? Evaluation of
effect of incorporation of silver nanoparticles of varying
particle size on the antimicrobial activity and properties of
irreversible hydrocolloid impression material. Dent Mater
(2018)
4.Ki-Young Nam1, Cheong-Hee Lee2 and Chul-Jae
Lee3.Antifungal and physical characteristics of modified
denture base acrylic incorporated with silver nanoparticles

47. 5.M. Samiei, M. Aghazadeh, M. Lotfi, S. Shakoei, Z.
Aghazadeh,and S. M.V. Pakdel, “Antimicrobial
efficacy of mineral trioxide aggregate with and
without silver nanoparticles,” Iranian Endodontic
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M. Saghiri, andV. Zand, “Antimicrobial efficacy of
nanosilver, sodiumhypochlorite and chlorhexidine
gluconate against Enterococcus faecalis,” African
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conditioner containing silver nanoparticles,” Journal of
Advanced Prosthodontics, vol. 3, no. 1, pp. 20–24,
2011.
8.Wenjuan Liu, Bin LiuYuanyuan Qi :Study on the
properties of the antibacterial alginate impression m
aterial 2012 International Conference on Biomedical
Engineering and Biotechnology