KR-12-a5 is a non-cytotoxic agent with potent antimicrobial effects against oral pathogens.

This study evaluated the cytotoxicity and antimicrobial activity of analogs of cationic peptides against microorganisms associated with endodontic infections. L-929 fibroblasts were exposed to LL-37, KR-12-a5 and hBD-3-1CV and chlorhexidine (CHX, control), and cell metabolism was evaluated with MTT. The minimal inhibitory concentration (MIC) and the minimal bactericidal/fungicidal concentration (MBC/MFC) of the peptides and CHX were determined against oral pathogens associated with endodontic infections. Enterococcus faecalis and Streptococcus mutans biofilms were cultivated in bovine dentin blocks, exposed to different concentrations of the most efficient antimicrobial peptide and analyzed by confocal laser scanning microscopy. CHX and peptides affected the metabolism of L-929 at concentrations > 31.25 and 500 µg ml-1, respectively. Among the peptides, KR-12-a5 inhibited growth of both the microorganisms tested with the lowest MIC/MBC/MFC values. In addition, KR-12-a5 significantly reduced E. faecalis and S. mutans biofilms inside dentin tubules. In conclusion, KR-12-a5 is a non-cytotoxic agent with potent antimicrobial and anti-biofilm activity against oral pathogens associated with endodontic infections.

Comparison of two different methods for detecting periodontal pathogenic bacteria

Aim: To perform a comparative analysis between two methods for detecting Porphyromonas gingivalis, Tannerella forsythia and Porphyromonas endodontalis in periodontal plaque samples. Methods: The study sample consisted of twenty systemically healthy patients showing generalized chronic periodontitis. The subgingival samples for microbiological analysis were collected before (baseline) and 60 days after a basic periodontal therapy from 30 non-adjacent affected sites (Probing Depth (PD): 5-7 mm, Clinical Attachment Loss (CAL) ≥ 5 mm, positive for Bleeding on Probing (BOP)). Microbiological analysis was performed by PCR and qPCR. To allow a comparative analysis between both methods, qPCR was divided in three different scores (score 2: presence of more than 100 bacteria; score 1: presence of 10-100 bacteria, and score 0: absence of bacteria), in accordance to DNA quantity, while for PCR two scores were assigned: presence or absence of bacteria. Results: qPCR demonstrated higher sensitivity in the detection of these pathogens compared with PCR when scores 1 and 2 were considered positive. However, when only score 2 was considered positive, PCR and qPCR showed better agreement. Conclusions: qPCR demonstrated higher sensitivity than conventional PCR for detection of low numbers of microorganisms and can be useful for the quantification of periodontopathogens. (AU)

Cytotoxicity and the effect of cationic peptide fragments against cariogenic bacteria under planktonic and biofilm conditions.

This study evaluated the cytotoxicity and effect of fragments derived from three oral cationic peptides (CP): LL-37, D6-17 and D1-23 against cariogenic bacteria under planktonic and biofilm conditions. For cytotoxicity analysis, two epithelial cell lines were used. The minimum inhibitory concentration and the minimal bactericidal concentration were determined for the CP fragments and the control (chlorhexidine-CHX) against cariogenic bacteria. The fractional inhibitory concentration was obtained for the combinations of CP fragments on Streptococcus mutans. Biofilm assays were conducted with the best antimicrobial CP fragment against S. mutans. The results indicated that D6-17 was not cytotoxic. D1-23, LL-37 and CHX were not cytotoxic in low concentrations. D1-23 presented the best bactericidal activity against S. mutans, S. mitis and S. salivarius. Combinations of CP fragments did not show a synergic effect. D1-23 presented a higher activity against S. mutans biofilm than CHX. It was concluded that D1-23 showed a substantial effect against cariogenic bacteria and low cytotoxicity.

Black Tea Extract and Its Theaflavin Derivatives Inhibit the Growth of Periodontopathogens and Modulate Interleukin-8 and ß-Defensin Secretion in Oral Epithelial Cells.

Over the years, several studies have brought evidence suggesting that tea polyphenols, mostly from green tea, may have oral health benefits. Since few data are available concerning the beneficial properties of black tea and its theaflavin derivatives against periodontal disease, the objective of this study was to investigate their antibacterial activity as well as their ability to modulate interleukin-8 and human ß-defensin (hBD) secretion in oral epithelial cells. Among the periodontopathogenic bacteria tested, Porphyromonas gingivalis was found to be highly susceptible to the black tea extract and theaflavins. Moreover, our data indicated that the black tea extract, theaflavin and theaflavin-3,3'-digallate can potentiate the antibacterial effect of metronidazole and tetracycline against P. gingivalis. Using lipopolysaccharide-stimulated oral epithelial cells, the black tea extract (100 µg/ml), as well as theaflavin and theaflavin-3,3'-digallate (50 µg/ml) reduced interleukin-8 (IL-8) secretion by 85%, 79%, and 86%, respectively, thus suggesting an anti-inflammatory property. The ability of the black tea extract and its theaflavin derivatives to induce the secretion of the antimicrobial peptides hBD-1, hBD-2 and hBD-4 by oral epithelial cells was then evaluated. Our results showed that the black tea extract as well as theaflavin-3,3'-digallate were able to increase the secretion of the three hBDs. In conclusion, the ability of a black tea extract and theaflavins to exert antibacterial activity against major periodontopathogens, to attenuate the secretion of IL-8, and to induce hBD secretion in oral epithelial cells suggest that these components may have a beneficial effect against periodontal disease.

Green tea extract and its major constituent epigallocatechin-3-gallate inhibit growth and halitosis-related properties of Solobacterium moorei.

BACKGROUND: Solobacterium moorei is a volatile sulfide compound (VSC)-producing Gram-positive anaerobic bacterium that has been associated with halitosis. The aim of this study was to investigate the effects of green tea extract and its major constituent epigallocatechin-3-gallate (EGCG) on growth and several halitosis-related properties of S. moorei. METHODS: A microplate dilution assay was used to determine the antibacterial activity of green tea extract and EGCG against S. moorei. Their effects on bacterial cell membrane integrity were investigated by transmission electron microscopy and a fluorescence-based permeability assay. Biofilm formation was quantified by crystal violet staining. Adhesion of FITC-labeled S. moorei to oral epithelial cells was monitored by fluorometry. The modulation of ß-galactosidase gene expression in S. moorei was evaluated by quantitative RT-PCR. RESULTS: The green tea extract as well as EGCG inhibited the growth of S. moorei, with MIC values of 500 and 250 µg/ml, respectively. Transmission electron microscopy analysis and a permeabilization assay brought evidence that the bacterial cell membrane was the target of green tea polyphenols. Regarding the effects of green tea polyphenols on the S. moorei colonization properties, it was found that biofilm formation on EGCG-treated surfaces was significantly affected, and that green tea extract and EGCG can cause the eradication of pre-formed S. moorei biofilms. Moreover, both the green tea extract and EGCG were found to reduce the adherence of S. moorei to oral epithelial cells. The ß-galactosidase activity of S. moorei, which plays a key role in VSC production, was dose-dependently inhibited by green tea polyphenols. In addition, EGCG at ½ MIC significantly decreased the ß-galactosidase gene expression. CONCLUSION: Our study brought evidence to support that green tea polyphenols possess a number of properties that may contribute to reduce S. moorei-related halitosis. Therefore, these natural compounds may be of interest to be used to supplement oral healthcare products.

Green tea polyphenol epigallocatechin-3-gallate and cranberry proanthocyanidins act in synergy with cathelicidin (LL-37) to reduce the LPS-induced inflammatory response in a three-dimensional co-culture model of gingival epithelial cells and fibroblasts.

OBJECTIVES: The human antimicrobial peptide cathelicidin (LL-37) possesses anti-inflammatory properties that may contribute to attenuating the inflammatory process associated with chronic periodontitis. Plant polyphenols, including those from cranberry and green tea, have been reported to reduce inflammatory cytokine secretion by host cells. In the present study, we hypothesized that A-type cranberry proanthocyanidins (AC-PACs) and green tea epigallocatechin-3-gallate (EGCG) act in synergy with LL-37 to reduce the secretion of inflammatory mediators by oral mucosal cells. METHODS: A three-dimensional (3D) co-culture model of gingival epithelial cells and fibroblasts treated with non-cytotoxic concentrations of AC-PACs (25 and 50 µg/ml), EGCG (1 and 5 µg/ml), and LL-37 (0.1 and 0.2 µM) individually and in combination (AC-PACs+LL-37 and EGCG+LL-37) were stimulated with Aggregatibacter actinomycetemcomitans lipopolysaccharide (LPS). Multiplex ELISA assays were used to quantify the secretion of 54 host factors, including chemokines, cytokines, growth factors, matrix metalloproteinases (MMPs), and tissue inhibitors of metalloproteinases (TIMPs). RESULTS: LL-37, AC-PACs, and EGCG, individually or in combination, had no effect on the regulation of MMP and TIMP secretion but inhibited the secretion of several cytokines. AC-PACs and LL-37 acted in synergy to reduce the secretion of CXC-chemokine ligand 1 (GRO-α), granulocyte colony-stimulating factor (G-CSF), and interleukin-6 (IL-6), and had an additive effect on reducing the secretion of interleukin-8 (IL-8), interferon-γ inducible protein 10 (IP-10), and monocyte chemoattractant protein-1 (MCP-1) in response to LPS stimulation. EGCG and LL-37 acted in synergy to reduce the secretion of GRO-α, G-CSF, IL-6, IL-8, and IP-10, and had an additive effect on MCP-1 secretion. CONCLUSION: The combination of LL-37 and natural polyphenols from cranberry and green tea acted in synergy to reduce the secretion of several cytokines by an LPS-stimulated 3D co-culture model of oral mucosal cells. Such combinations show promising results as potential adjunctive therapies for treating inflammatory periodontitis.

Synergistic anti-inflammatory activity of the antimicrobial peptides human beta-defensin-3 (hBD-3) and cathelicidin (LL-37) in a three-dimensional co-culture model of gingival epithelial cells and fibroblasts.

Given the spread of antibiotic resistance in bacterial pathogens, antimicrobial peptides that can also modulate the immune response may be a novel approach for effectively controlling periodontal infections. In the present study, we used a three-dimensional (3D) co-culture model of gingival epithelial cells and fibroblasts stimulated with Aggregatibacter actinomycetemcomitans lipopolysaccharide (LPS) to investigate the anti-inflammatory properties of human beta-defensin-3 (hBD-3) and cathelicidin (LL-37) and to determine whether these antimicrobial peptides can act in synergy. The 3D co-culture model composed of gingival fibroblasts embedded in a collagen matrix overlaid with gingival epithelial cells had a synergistic effect with respect to the secretion of IL-6 and IL-8 in response to LPS stimulation compared to fibroblasts and epithelial cells alone. The 3D co-culture model was stimulated with non-cytotoxic concentrations of hBD-3 (10 and 20 µM) and LL-37 (0.1 and 0.2 µM) individually and in combination in the presence of A. actinomycetemcomitans LPS. A multiplex ELISA assay was used to quantify the secretion of 41 different cytokines. hBD-3 and LL-37 acted in synergy to reduce the secretion of GRO-alpha, G-CSF, IP-10, IL-6, and MCP-1, but only had an additive effect on reducing the secretion of IL-8 in response to A. actinomycetemcomitans LPS stimulation. The present study showed that hBD-3 acted in synergy with LL-37 to reduce the secretion of cytokines by an LPS-stimulated 3D model of gingival mucosa. This combination of antimicrobial peptides thus shows promising potential as an adjunctive therapy for treating inflammatory periodontitis.

Subinhibitory concentrations of triclosan promote Streptococcus mutans biofilm formation and adherence to oral epithelial cells.

Triclosan is a general membrane-active agent with a broad-spectrum antimicrobial activity that is commonly used in oral care products. In this study, we investigated the effect of sub-minimum inhibitory concentrations (MICs) of triclosan on the capacity of the cariogenic bacterium Streptococcus mutans to form biofilm and adhere to oral epithelial cells. As quantified by crystal violet staining, biofilm formation by two reference strains of S. mutans was dose-dependently promoted, in the range of 2.2- to 6.2-fold, by 1/2 and 1/4 MIC of triclosan. Observations by scanning electron microscopy revealed the presence of a dense biofilm attached to the polystyrene surface. Growth of S. mutans in the presence of triclosan at sub-MICs also increased its capacity to adhere to a monolayer of gingival epithelial cells. The expression of several genes involved in adherence and biofilm formation in S. mutans was investigated by quantitative RT-PCR. It was found that sub-MICs of triclosan significantly increased the expression of comD, gtfC, and luxS, and to a lesser extent of gtfB and atlA genes. These findings stress the importance of maintaining effective bactericidal concentrations of therapeutic triclosan since sub-MICs may promote colonization of the oral cavity by S. mutans.

Efeito antimicrobiano e modulador da resposta imune dos peptídeos hBD-3 e LL-37 e dos polifenóis do chá verde e do cranberry / Antimicrobial and immune regulatory activity of the peptides hBD-3, LL-37 and the polyphenols from cranberry and green tea

Os peptídeos antimicrobianos como por exemplo a catelicina (LL-37) e as defensinas humanas (hBD-1, hBD-2 e a hBD-3) são considerados antibióticos endógenos com importante papel na prevenção das doenças periodontais, devido a sua capacidade de regulação da resposta imune, sendo que os mesmos podem ser degradados pelos periodontopatógenos. Terapias que aumentem a produção destes peptídeos pelas próprias células do organismo, assim como a associação destes peptídeos com compostos naturais os quais possam agir em sinergismo na regulação da resposta imune, podem ser considerados novas estratégias para o melhor controle das doenças periodontais. Portanto os objetivos deste estudo in vitro foram: i) Avaliar a capacidade do extrato do chá verde (Camellia sinensis) e do seu polifenol, o EGCG, sobre a expressão gênica de hBD-1 e hBD-2 pelas células epiteliais gengivais (B11), sobre a degradação das mesmas frente ao P. gingivalis, ii) Através da utilização do modelo 3D de co-cultura celular, avaliar a capacidade antiinflamatória dos peptídeos hBD-3 e LL-37 quando em associação sobre a produção de citocinas, quimiocinas e fatores de crescimento, iii) Avaliar a capacidade anti-inflamatória da associação do EGCG e do polifenol proveniente do cranberry, o AC-PACs, com o peptídeo LL-37 sobre a produção de citocinas, quimiocinas e fatores de crescimento em modelo de co-cultura celular. As células epiteliais gengivais (B11) foram estimuladas com o extrato do chá verde e com o EGCG na presença e ausência de inibidores específicos. A produção e expressão gênica de hBD-1 e hBD-2 foram quantificados respectivamente pelas técnica de ELISA e qPCR. A capacidade do extrato do chá verde e do EGCG em proteger a degradação de hBDs pelo P. gingivalis foi mensurado através da técnica de ELISA. Foi desenvolvido um modelo em 3D de co-cultura de fibroblastos gengivais embebidos em uma matriz de colágeno com células epiteliais gengivais semeadas em sua superfície, no qual observou-se efeito sinérgico das células na secreção de IL-6 e IL-8 em resposta ao estímulo com LPS de A. actinomycetemcomitans (1 µg/ml) quando comparados as células individuais. Em seguida o modelo em 3D de co-cultura celular na presença no LPS de A. actinomycetemcomitans foi estimulado com: i) hBD-3 (10 and 20 µM) e LL-37 (0.1 and 0.2 µM), ii) EGCG (1 e 5 µg/ml) e LL-37 (0.1 and 0.2 µM) e iii) AC-PACs (25 e 50 µg/ml) e LL-37 (0.1 and 0.2 µM), individualmente e em associação. Foi utilizada a técnica de ELISA Multiplex para quantificar 41 diferentes citocinas, quimiocinas, fatores de crescimentos e 13 diferentes MMPs e TIMPs. Os resultados demonstraram que: i) o extrato do chá verde e o EGCG aumentaram a produção e a expressão gênica de hBD-1 e hBD-2 pelas células epiteliais de uma maneira dose-dependente, e foram capazes de prevenir a degradação das hBD-1 e hBD-2 recombinantes pelo sobrenadante de P. gingivalis, ii) o peptídeo hBD-3 em associação com o LL37 mostrou efeito sinérgico na diminuição da produção de GRO-α, G-CSF, IP-10, IL-6, e MCP1, entretanto teve apenas efeito aditivo na redução da produção de IL-8 em resposta ao estímulo com LPS de A. actinomycetemcomitans, iii) a associação do peptídeo LL-37 com o EGCG e com o AC-PACs mostraram efeito sinérgico na redução da produção de GRO-α, G-CSF e IL-6 em resposta ao estímulo com LPS de A. actinomycetemcomitans. Portanto os peptídeos antimicrobianos hBD-3 e LL-37, assim como o extrato do chá verde, o EGCG e o AC-PACs por demonstrarem capacidade de regular a produção de citocinas inflamatórias, induzir a produção de defensinas pelas próprias células e proteger as defensinas da degradação pelo P. gingivalis surgem como promissores alternativas para terapias adjuntas ao tratamento periodontal convencional. Entretanto estudos clínicos futuros são necessários para avaliar o papel dos peptídeos e dos compostos naturais na cavidade oral e na proteção dos tecidos periodontais frente à uma agressão

The antimicrobial peptides LL-37, hBD-1, hBD-2 and hBD-3 are considered an endogenous antibiotic, with important role in the prevention of periodontal diseases due to their ability to regulate the immune response. However those peptides could be degraded by periodontal pathogens. Therefore, therapies able to up regulate the secretion of those peptides by human cells, and the association of antimicrobial peptides with natural compounds, which may act in synergism to modulate the immune response, may be a novel approach for effectively controlling periodontal diseases. The aim of this in vitro study were: i) investigate the ability of green tea extract and EGCG to induce hBD-1 and hBD-2 secretion and gene expression by gingival epithelial cells (B11) and to protect hBDs from degradation by P. gingivalis, ii) A 3D co-culture model of gingival epithelial cells and fibroblasts stimulated with A. actinomycetemcomitans LPS (1 µg/ml) were used to investigated the anti-inflammatory properties of the hBD-3, LL-37, ACPACs and EGCG and to determine whether LL-37 acts in synergy with AC-PACs, EGCG and hBD-3. Gingival epithelial cells were stimulated with green tea extract or EGCG in the presence and absence of specific inhibitors. The secretion and gene expression of hBD-1 and hBD-2 was respectively measured by ELISA and qPCR. The ability of green tea extract and EGCG to prevent hBDs degradation by P. gingivalis present in a bacterial culture supernatant was evaluated by ELISA. A 3D co-culture model composed of gingival fibroblasts embedded in a collagen matrix overlaid with gingival epithelial cells had a synergistic effect with respect to the secretion of IL-6 and IL-8 in response to A. actinomycetemcomitans LPS stimulation compared to fibroblasts and epithelial cells individually. The 3D co-culture model was stimulated with noncytotoxic concentrations of: i) hBD-3 (10 and 20 µM) and LL -37 (0.1 and 0.2 µM), ii ) EGCG (1 and 5 µg/ml) and LL -37 (0.1 and 0.2 µM), iii) AC- PACs (25 and 50 µg/ml) and LL-37 (0.1 and 0.2 µM) alone and in association in the presence of A. actinomycetemcomitans LPS. A multiplex ELISA assay was used to quantify the secretion of 41 different cytokines, chemokines, growth factors and 13 different MMPs and TIMPs. Ours results showed that: i) the secretion and gene expression of hBD-1 and hBD-2 was up-regulated in a dose-dependent manner by green tea extract and EGCG. Green tea extract and EGCG were also able to prevent the degradation of recombinant hBD-1 and hBD-2 by a culture supernatant of P. gingivalis, ii) hBD-3 in association with LL-37 showed a synergistic effect to reduce the secretion of GRO- α, G-CSF, IP- 10, IL -6 and MCP -1, however had only additive effect on reducing the secretion of IL-8 in response to A. actinomycetemcomitans LPS stimulation, iii) the association of the peptide LL- 37 with EGCG and with AC- PACs showed a synergistic effect to reduce the secretion of GRO-α, G-CSF and IL-6 in response to A. actinomycetemcomitans LPS stimulation. Considering that the antimicrobial peptides hBD-3 and LL-37, as well as green tea extract, EGCG and AC- PACs, demonstrated the ability to regulate the secretion of inflammatory cytokines, up regulated the secretion of defensins by the cells and even to protect the defensins degradation by P. gingivalis, emerged as promising alternative adjunct therapy to conventional periodontal treatment. However future clinical studies are necessary to evaluate the role of peptides and natural compounds in the oral cavity and periodontal tissues

Aesthetic rehabilitation of oligodontia in primary dentition with adhesive partial denture.

The primary teeth are essential for bone development and establishment of the arches on occlusion. Thus, the congenitally absence of teeth may trigger a shift in the balance of the occlusion, promoting disharmony in the structures of the maxilla-mandibular system. However, some interventions are possible to be performed in these cases even in pediatric patients, to redirect growth, preventing growth deviations and reestablishing the aesthetic. The aim of this paper is to report the treatment of a 4-year-old child presenting congenitally absence of mandibular central and lateral incisors and maxilla lateral incisors, which consequently compromises aesthetics, occlusal function, and the development and the functional growth of the bones. The oral rehabilitation was performed with an adhesive partial denture, which was able to restore the aesthetic and the occlusal function, therefore being a viable alternative in the treatment of this patient of little age.

Avaliação comparativa ?in vivo? da eficácia do óleo de melaleuca, clorexidina e listerine sobre streptococcus mutans e microrganismos totais na saliva / ?In Vivo? Comparative Evaluation of the Efficacy of Melaleuca Oil, Chlorhexidine and Listerine against Streptococcus mutans and Total Microorganisms in Saliva

Objetivo: Comparar a eficácia dos enxaguatórios bucais: clorexidina 0,12%, Listerine e óleo de Melaleuca Alternifolia 0,5% e 2% sobre os níveis salivares de Streptococcus mutans e microrganismos totais. Métodos: O estudo foi um ensaio clínico, controlado, duplo cego e emparelhado. Para tanto foram selecionados 26 voluntários com idade entre 21 - 35 anos. Foi coletada de cada participante, no baseline, a quantidade de 1 mL de saliva não estimulada, 1 e 15 min após os bochechos com as seguintes soluções: água destilada estéril, digluconato de clorexidina 0,12%, Listerine (©Johnson & Johnson do Brasil), Melaleuca Alternifolia (Sigma-Aldrich St Louis, MO, USA) nas concentrações de 0,5% e 2%. Os participantes fizeram uso de todos os enxaguatórios bucais pesquisados, com intervalo de 15 dias entre cada solução. Imediatamente após o bochecho, foi coletada a saliva e realizadas as diluições seriadas, seguidas de plaqueamento em meio de cultura Agar sangue para o crescimento de microrganismos totais e SB-20 (Agar Sacarose Bacitracina) para S. mutans, mantidos por 48h a 37°C em microaerofilia. Após o período de incubação, as colônias foram contadas e transformadas em unidades formadoras de colônias (UFC/mL). Resultados: A clorexidina mostrou ação antimicrobiana na redução dos microrganismos totais e S. mutans, enquanto a ação do óleo Melaleuca Alternifolia 0.5% foi semelhante à água destilada. O listerine e o óleoMelaleuca Alternifolia 2% apresentaram redução microbiana, respectivamente, de 11% e 9% para microrganismos totais, entretanto para S. mutans o listerine reduziu os níveis em 20% e o óleo Melaleuca Alternifolia 2% em 11%. Conclusão: O bochecho único com clorexidina 0,12% é eficaz na redução de níveis de microrganismos totais e S. mutans presentes na saliva. Ao comparar a clorexidina com o listerine e óleo Melaleuca Alternifolia 0,5% e 2% nas mesmas condições a eficácia da ação destas soluções é diminuída.

Objective: To compare the efficacy of the mouthwashes 0.12% chlorhexidine, Listerine, and 0.5% and 2% Melaleuca Alternifolia oil against the salivary levels of Streptococcus mutans and total microorganisms.Methods: This study was double-blind controlled and paired clinical assay. Twenty-six volunteers aged 21 to 35 years old were enrolled. At baseline, 1 mL of unstimulated saliva was collected from each subject, 1 and 15 min after mouthrinsing with the following solutions: sterile distilled water, 0.12% chlorhexidine digluconate, Listerine (©Johnson & Johnson do Brasil), 0.5% and 2% concentrations of Melaleuca Alternifolia (Sigma-Aldrich). The volunteers used all the evaluated mouthrinses with a 15-day interval between the solutions. Immediately after rinsing, saliva was collected and serial dilutions were performed, followed by plating in blood agar culture medium for growth of total microorganisms and SB-20 (Sucrose-Bacitracin agar) for growth of S. mutans, and incubation at 37 °C for 48 h in microaerophilia. After incubation, the number of colonies was counted and expressed as colony forming units (UFC/mL).Results: Chlorhexidine showed antimicrobial action by reducing total microorganisms and S. mutans, while the action of 0.5% Melaleuca Alternifolia was similar to that of distilled water. Listerine and 2%Melaleuca Alternifolia oil reduced total microbial counts by 11% and 9% respectively, and S. mutans by 20% and 11%.Conclusion: A single rinse with 0.12% chlorhexidine is effective in reducing the levels of total microorganisms and S. mutans present in saliva. Under the same testing conditions, Listerine and 0.5% and 2%Melaleuca Alternifolia oil presented lower efficacy than chlorhexidine.

Fibrinogen-induced streptococcus mutans biofilm formation and adherence to endothelial cells.

Streptococcus mutans, the predominant bacterial species associated with dental caries, can enter the bloodstream and cause infective endocarditis. The aim of this study was to investigate S. mutans biofilm formation and adherence to endothelial cells induced by human fibrinogen. The putative mechanism by which biofilm formation is induced as well as the impact of fibrinogen on S. mutans resistance to penicillin was also evaluated. Bovine plasma dose dependently induced biofilm formation by S. mutans. Of the various plasma proteins tested, only fibrinogen promoted the formation of biofilm in a dose-dependent manner. Scanning electron microscopy observations revealed the presence of complex aggregates of bacterial cells firmly attached to the polystyrene support. S. mutans in biofilms induced by the presence of fibrinogen was markedly resistant to the bactericidal effect of penicillin. Fibrinogen also significantly increased the adherence of S. mutans to endothelial cells. Neither S. mutans cells nor culture supernatants converted fibrinogen into fibrin. However, fibrinogen is specifically bound to the cell surface of S. mutans and may act as a bridging molecule to mediate biofilm formation. In conclusion, our study identified a new mechanism promoting S. mutans biofilm formation and adherence to endothelial cells which may contribute to infective endocarditis.

Porphyromonas endodontalis in chronic periodontitis: a clinical and microbiological cross-sectional study.

BACKGROUND: Although previous studies have shown the presence of Porphyromonas endodontalis in chronic periodontitis associated with periapical lesions, the occurrence of this pathogen in diseased periodontal sites without periapical lesions has been poorly investigated. OBJECTIVE: The aims of this study were to quantify P. endodontalis in patients with chronic periodontitis without periapical lesions, to evaluate the potential correlation of P. endodontalis with Porphyromonas gingivalis and Tannerella forsythia, and to evaluate the ability of periodontal treatment to reduce these pathogens. DESIGN: Patients with generalized chronic periodontitis were selected by recording clinical attachment level (CAL), probing depth (PD), and bleeding on probing (BOP). Subgingival samples from 30 diseased nonadjacent sites (CAL≥5 mm, PD between 5 and 7 mm and positive BOP) and 30 healthy nonadjacent sites (PD≤3 mm and negative BOP) were collected and subjected to microbial analysis by quantitative polymerase chain reaction (qPCR) The variables of age, PD, CAL and BOP of all individuals were analyzed using the paired t-test (GrapPad Prism5(®)). Data of bacteria quantification were subjected to a normality test (D'Agostino-Pearson Test). For bacterial correlation analysis, the Spearman correlation was used. RESULTS: Our results showed that diseased sites had significantly higher levels of P. endodontalis compared to healthy sites, similar to the results obtained for P. gingivalis and T. forsythia. The numbers of all bacterial species were reduced significantly after mechanical periodontal treatment. P. endodontalis was significantly correlated with the presence of T. forsythia and P. gingivalis in the diseased group. CONCLUSION: Our results suggest that there is a high prevalence of P. endodontalis, P. gingivalis and T. forsythia in periodontitis sites and that mechanical periodontal treatment is effective at reducing the pathogens studied.

Porphyromonas gingivalis-mediated shedding of extracellular matrix metalloproteinase inducer (EMMPRIN) by oral epithelial cells: a potential role in inflammatory periodontal disease.

Extracellular matrix metalloproteinase inducer (EMMPRIN) or CD147 is a transmembrane glycoprotein expressed by various cell types, including oral epithelial cells. Recent studies have brought evidence that EMMPRIN plays a role in periodontitis. In the present study, we investigated the effect of Porphyromonas gingivalis, a major pathogen in chronic periodontitis, on the shedding of membrane-anchored EMMPRIN and on the expression of the EMMPRIN gene by oral epithelial cells. A potential contribution of shed EMMPRIN to the inflammatory process of periodontitis was analyzed by evaluating the effect of recombinant EMMPRIN on cytokine and matrix metalloproteinase (MMP) secretion by human gingival fibroblasts. ELISA and immunofluorescence analyses revealed that P. gingivalis mediated the shedding of epithelial cell-surface EMMPRIN in a dose- and time-dependent manner. Cysteine proteinase (gingipain)-deficient P. gingivalis mutants were used to demonstrate that both Arg- and Lys-gingipain activities are involved in EMMPRIN shedding. Real-time PCR showed that P. gingivalis had no significant effect on the expression of the EMMPRIN gene in epithelial cells. Recombinant EMMPRIN induced the secretion of IL-6 and MMP-3 by gingival fibroblasts, a phenomenon that appears to involve mitogen activated protein kinases. The present study brought to light a new mechanism by which P. gingivalis can promote the inflammatory response during periodontitis.

Incisive canal deflation for correct implant placement: case report.

AIM: This article is a case report of a patient in whom the prosthetic planning indicated the necessity of an incisive canal deflation for the correct installation of an implant that is to be osseointegrated. CASE REPORT: In the reopening phase after the bone graft installation, the incisive canal deflation (biopsy of its content) was done and titanium implants were installed with one of them invading the anatomical space occupied previously by the incisive canal. The biopsy analysis showed fragments of the incisive artery and nerve, which are responsible for the anterior upper-tooth pulp, the periodontium vascularization and the innervation. From the anastomosis present along with other structures allied with the absence of teeth in the region, there was no detriment to the patient caused by the deflation. CONCLUSION: Incisive canal deflation is a viable technique in implantology. It can permit ideal prosthetic planning with no detriment to the patient.