VoxLim

HA - UNILEVER Travel Award (Hatton)
HA001 Immunolocalization of stem cell markers in the pulp of human
permanent teeth
Machado CV*, Passos ST, Campos TMC, Nör JE, Nascimento ILO,
Telles PDS
Odontologia Social e Pediátrica - UNIVERSIDADE FEDERAL DA BAHIA.
E-mail: cintiamachado@hotmail.com
Niches are special microenvironments in tissues where stem cells reside. At this sites, complex
molecular interactions occur, which maintain the essential properties of these cells, like self
renewal and plasticity. Some adult stem cell niches had already been described, but most of
them remain unclear, including the dental pulp stem cells niches. Understanding how stem cells
behave in the niche is strongly important to extract these cells from the naturalhabitat, expand
them in vitro and transplant the stem cells back to the patient, to repair and/or regenerate
tissues and organs, with no risks to the individual integrity. Therefore, the aim of this study was
to detect, by immunohistochemistry, cells expressing STRO-1 and CD90, as well as ALDH1
(aldehyde dehydrogenase1), an enzyme that has been used to identify hematopoietic and cancer
stem cells, in the pulp of human permanent teeth. Likewise, we intended to isolate, grow and
evaluate pulp cells from these teeth for stem cells parameters. ALDH1, CD90 and STRO-1
positive cells were detected in the perivascular areas and nerve fibers of the dental pulp by
immunohistochemistry. Cells on fifth passage showed high expression for CD44, CD73 and
CD90, whereas moderate labeling was observed for STRO-1 and ALDH1 in flow cytometry
analysis. On the same passages, cells were able to differentiate into osteogenic, adipogenic and
chondrogenic lineages.
Our results suggest that pulp stem cells reside in the vicinity of blood vessels and nerve fibers,
as indicate the possible existence of more than one stem cell niche in the dental pulp. Likewise,
the isolated pulp cells can be considered stem cells. (Apoio: FAPESB - BOL0541/2010)
HA002 Host defense peptides in endodontics: antimicrobial, immune response
and osteoclastogenesis analysisin vitro
Lima SMF*, Sousa MGC, Freire MS, Cantuária APC, Almeida JA, Dias SC,
Franco OL, Rezende TMB
Ciências Genômicas e Biotecnologia - UNIVERSIDADE CATÓLICA DE BRASÍLIA.
E-mail: stellalimaf@gmail.com
Microbial resistance has stimulated the development of novel therapies in endodontics. In
this regard, this study aimed to evaluate thein vitro role of host-defense peptides (HDPs)
clavanins A, MO and LL-37 as well Ca(OH)2 in an infection model. Firstly, antimicrobial
assays were conducted against Enterococcus faecalis and Candida albicans. Moreover, RAW
264.7 cells were also incubated with HDPs and Ca(OH)2 in the presence or absence of heat
killed (HK) antigens and IFN-γ . Cell viability was performed by MTT assay and immune
response was determined by cytokine (TNF-α, MCP-1, IL-1α, IL-6, IL-10 and IL-12) and
nitric oxide (NO) production. Detection of receptor activator of nuclear factor kappa B ligand
(RANKL)-mediated osteoclastogenesis was analyzed. Data here obtained demonstrated that
minimum inhibitory concentrations were 1728 µM to C. albicans (Ca(OH)2) and 13820 µM
and 57 µM to E. faecalis (Ca(OH)2 and LL-37 respectively). Otherwise, only clavanin MO
reduced cell viability. Additionally, immune-response studies were performed in RAW cells
showed that Ca(OH)2 up-regulated MCP-1, TNF-α, IL-12 and IL-6 and down-regulate IL-1α,
IL-10 and NO production. HDPs up-regulated TNF-α and down-regulated IL-10 and NO
synthesis. HDPs and Ca(OH)2 reduced the osteoclast differentiated cells number.
In conclusion, HDPs demonstrated an anti-inflammatory activity while Ca(OH)2 exhibit
a pro-inflammatory effect, despite the similar effects over osteoclastogenesis and microbial
growth, showing HDPs abilities for infection control and for inducing tissue repair in
endodontics. (Apoio: CNPq - 470477/2012-1)
HA003 Efectiveness of photodynamic therapy without extrinsic photosensitizers
on Streptococcus mutans biofilm
Sousa DL*, Lima RA, Duarte S
Odontologia Restauradora - UNIVERSIDADE FEDERAL DO CEARÁ.
E-mail: lins.denise@yahoo.com.br
The aim of this study was to evaluate the efficacy of phototherapy without extrinsic
photosensitizer on theStreptococcus mutans biofilm. Biofilms of S. mutans UA159 were formed
on saliva-coated hydroxyapatite discs for 5 days and were exposed twice daily to noncoherent
blue light (420 nm), red light (570 - 690 nm) and white light (400 - 700 nm).
The energy density was 72 J/cm2. Positive and negative controls were 0.12% chlorhexidine
and 0.89% NaCl, respectively. Biofilms were analyzed for bacterial viability, dry-weight,
extracellular polysaccharides (EPS-insoluble and EPS-soluble) and intracellular polysaccharide
(IPS). Variable pressure scanning electron microscopy and confocal laser scanning microscopy
were performed. Daily exposure of biofilm to blue, red and white lights showed a reduction
in bacterial viability but they weren’t statistically different from the negative control (p>0.05).
Red and white lights increased the levels of EPS-soluble and EPS-insoluble when compared to
negative control (p > 0.05). Blue light showed a significant reduction in dry weight and in the
levels of EPS-soluble and EPS-insoluble when compared to positive control (p0.05). Different morphology and higher proportion of dead
cells were also visible when the biofilms were treated with blue light.
We conclude that the daily treatment with blue light is a promising mechanism for the
inhibition of matrix-rich biofilm formation.
HA004 Atmospheric pressure cold plasma: a tissue-tolerable approach against
oral biofilms
Delben JA*, Zago CE, Tyhovych N, Vergani CE, Duarte S
Materiais Odontológicos e Prótese - UNIVERSIDADE ESTADUAL PAULISTA - ARARAQUARA.
E-mail: ju.del@ig.com.br
This study determined the effect of atmospheric pressure cold plasma (ACP) on reconstituted
oral epithelium and single- and dual-specie biofilms ofCandida albicans and Staphylococcus
aureus. Single- and dual-specie biofilms of C. albicans (SC5314) and S. aureus (ATCC25923)
were cultured on sterilized acrylic resin discs with RPMI medium at 37°C for 48 hours. ACP
treatment by ionization of argon gas was conducted at plasma tip-to-sample distance of 10
mm during 60 seconds under gas flow set to 5 slm. The biofilms were assessed for microbial
viability by confocal laser scanning microscopy and CFU/ml counting. Biofilm morphology
was analyzed by scanning electron microscopy. For the effects of ACP on oral tissue, an in
vitro reconstituted oral epithelium model based on primary oral keratinocytes cultured on a
collagen-based matrix was submitted to similar ACP treatment. The epithelium was evaluated
by histology, cytotoxicity analysis based on lactate dehydrogenase release, cell viability by
MTT assay, and immunohistochemistry for caspase 3 and Ki-67. ACP treatment affected the
viability of both single- and dual-specie biofilms. ACP-treated biofilms also showed significant
morphology alterations. Similar percent cytotoxicity and epithelial cell viability were observed
for negative control and ACP group. Histology and immunohistochemistry showed no sign of
necrosis or significant alteration in ACP-treated tissue
We concluded that ACP is a promissing effective approach against single- and dual-specie
biofilms with no significant damage to oral tissue. (Apoio: FAPESP - 2012/20699-6)
HA005 Photodynamic antimicrobial chemotherapy against formingS.mutans
biofilms
Lima RA*, Zanin ICJ, Sousa DL, Duarte S
Clínica Odontológica - UNIVERSIDADE FEDERAL DO CEARÁ.
E-mail: ramillelima@yahoo.com.br
The study investigated the effect of photodynamic antimicrobial chemotherapy (PACT)
performed with the red light source LumaCare LC122® (630nm) and 1% orto-toluidine
blue (TBO) on the microbial viability, weight, polysaccharide formation and morphology of
formingS. mutans UA 159 biofilms. The biofilms were formed on saliva-coated hydroxyapatite
discs in batch culture at 37oC, 5% CO2. Tryptone-yeast extract broth containing 1% sucrose
was changed daily. From 1st to 5th day, the biofilms were treated with an association of 1%
TBO and LumaCare® (LC) as follow: TBO+LC149J/cm2 (L+S+ 1min); TBO + LC317.05J/
cm2 (L+S+ 2min); without TBO and light (L-S-); with TBO and without light (L-S+); without
TBO+LC149J/cm2 (L+S- 1min); without TBO+ LC317.05J/cm2 (L+S- 2min); 0.12%
Chlorhexidine digluconate (CHX). At 5th day, biofilms were collected, disrupted, diluted and
plated for counting (CFU/mg). The biofilm morphology was determined by variable-pressure
scanning electron microscopy. L+S+ 2min achieved the best microbial viability reduction,
statistically different to all other groups (p0.05), but different from others. Dry weight of L+S+1min (2.4mg), L+S+2 min
(1.18mg) and CHX (4.39mg) was statistically similar (p>0.05), but different from negative
control groups (p