Activation of Toll-like receptor 2 induces B1 and B2 kinin receptors in human gingival fibroblasts and in mouse gingiva.

The regulation of the kallikrein-kinin system is an important mechanism controlling vasodilation and promoting inflammation. We aimed to investigate the role of Toll-like receptor 2 (TLR2) in regulating kinin B1 and B2 receptor expression in human gingival fibroblasts and in mouse gingiva. Both P. gingivalis LPS and the synthetic TLR2 agonist Pam2CSK4 increased kinin receptor transcripts. Silencing of TLR2, but not of TLR4, inhibited the induction of kinin receptor transcripts by both P. gingivalis LPS and Pam2CSK4. Human gingival fibroblasts (HGF) exposed to Pam2CSK4 increased binding sites for bradykinin (BK, B2 receptor agonist) and des-Arg10-Lys-bradykinin (DALBK, B1 receptor agonist). Pre-treatment of HGF for 24 h with Pam2CSK4 resulted in increased PGE2 release in response to BK and DALBK. The increase of B1 and B2 receptor transcripts by P. gingivalis LPS was not blocked by IL-1ß neutralizing antibody; TNF-α blocking antibody did not affect B1 receptor up-regulation, but partially blocked increase of B2 receptor mRNA. Injection of P. gingivalis LPS in mouse gingiva induced an increase of B1 and B2 receptor mRNA. These data show that activation of TLR2 in human gingival fibroblasts as well as in mouse gingival tissue leads to increase of B1 and B2 receptor mRNA and protein.

Elimination of Candida albicans infection of the radicular dentin by intracanal medications.

Fungi have been associated with cases of secondary or persistent root canal infections. The purpose of this study was to evaluate the effectiveness of four intracanal medications in disinfecting the root dentin of bovine teeth experimentally infected with Candida albicans. Infected dentin cylinders were exposed to four different medications: calcium hydroxide/glycerin; calcium hydroxide/0.12% chlorhexidine digluconate; calcium hydroxide/camphorated paramonochlorophenol/glycerin; and 0.12% chlorhexidine digluconate/zinc oxide. Specimens were in contact with the medications for 1 h, 2 days, and 7 days. The viability of C. albicans after exposure was evaluated by specimen incubation in culture medium to compare the effectiveness of the medications in disinfecting dentin. Results showed that the specimens treated with calcium hydroxide/camphorated paramonochlorophenol/ glycerin paste or with chlorhexidine/zinc oxide paste were completely disinfected after 1 h of exposure. Calcium hydroxide/glycerin paste only consistently eliminated C. albicans infection after 7 days of exposure. Calcium hydroxide mixed with chlorhexidine was ineffective in disinfecting dentin even after 1 week of medication exposure. Among the medications tested, the calcium hydroxide/camphorated paramonochlorophenol/glycerin paste and chlorhexidine digluconate mixed with zinc oxide were the most effective in eliminating C. albicans cells from dentinal specimens.

Efficacy of instrumentation techniques and irrigation regimens in reducing the bacterial population within root canals.

The purpose of this study was to compare the in vitro intracanal bacterial reduction produced by using two instrumentation techniques and different irrigation methods. Root canals inoculated with Enterococcus faecalis were prepared by using the following techniques and irrigants: alternated rotary motions (ARM) technique, hand nickel-titanium files and 2.5% sodium hypochlorite (NaOCl) as irrigant; ARM technique and combined irrigation with 2.5% NaOCl and citric acid; ARM technique and combined irrigation with 2.5% NaOCl and 2% chlorhexidine gluconate; and Greater Taper rotary files, using 2.5% NaOCl as irrigant. Controls were instrumented by using the ARM technique and irrigated with sterile saline. Canals were sampled before and after preparation. After serial dilution, samples were plated onto Mitis-Salivarius agar, and the colony forming units that were grown were counted. All test techniques and solutions significantly reduced the number of bacterial cells within the root canal (p < 0.05). There was no significant difference between the experimental groups (p > 0.05). Nonetheless, all of them were significantly more effective than the control group (p < 0.05). These findings support the importance of using antimicrobial irrigants during the chemomechanical preparation, regardless of the solutions or instrumentation techniques used.

Levels of infection and colonization of some oral bacteria after use of naf, chlorhexidine and a combined chlorhexidine with naf mouthrinses

O objetivo deste estudo foi avaliar os níveis de infecção de bactérias cariogênicas e estreptococos orais e sua colonização após uso de bochechos com NaF, clorexidina e clorexidina e NaF associados. Associação de clorexidina e NaF foi o único agente que reduziu os níveis de Streptococcus mutans (grupo) por 30 dias.

Efeitos de hidróxido de cálcio associado a diferentes veículos sobre dentina contaminada / Effects of calcium hydroxide associated with different vehicles on dentin contaminated

Cilindros de dentina bovina foram experimentalmente contaminados com uma cultura mista de Fusobacterium nucleatum e Prevotella intermedia, duas espécies bacterianas anaeróbicas estritas, comumente encontradas em infecçöes endodônticas. Estes espécimes foram expostos a quatro formulaçöes diferentes de pastas de hidróxido de cálcio (HC). Os espécimes foram deixados em contato com as pastas por 3 e 5 dias. Finalizados estes períodos a viabilidade bacteriana foi avaliada, através de incubaçäo dos espécimes em caldo de cultura, de forma a comparar a efetividade das pastas na descontaminaçäo da dentina. Apenas a pasta HPG foi capaz de, efetivamente, descontaminar a dentina após 5 dias de contato

Efeito antibacteriano do hipoclorito de sódio a 1 por cento e a 5.25 por cento sobre bacilos anaeróbicos produtores de pigmentos negros / Antibacterial effects of 1 percent and 5.25 per cent sodium hypochlorite on black-pigmented anaerobic rods

Os efeitos antibacterianos das soluçöes de hipoclorito de sódio a 1 por cento e a 5,25 por cento sobre bacilos anaeróbios produtores de pigmentos negros foram avaliados. As espécies bacterianas utilizadas neste estudo foram: Porphyromonas endondontalis; Porphyromonas gingivalis; Prevotella intermedia; e Prevotella nigrescens. O teste de difusäo em ágar foi a metodologia empregada. Os resultados demonstraram que ambas as soluçöes testadas apresentaram atividade antibacteriana satisfatória. A soluçäo a 5,25 por cento apresentou halos de inibiçäo de maiores diâmetros, sendo a mais eficaz

Atividade antibacteriana da pasta de hidróxido de cálcio/paramonoclorofenol canforado/glicerina contendo diferentes proporçöes de iodofórmio sobre bactérias anaeróbias estritas e facultativas / The antibacterial activity of calcium hydroxide camphorated paramonochlorophenol glycerin past containing differet amounts of iodorform against obligate and facultative anaerobic bacteria

A atividade antibacteriana de pasta à base de hidróxido de cálcio/paramonoclorofenol cnforado/glicerina (H/P/G) contendo diferentes proporções de iodofórmio foi testada contra 3 bactérias anaeróbias estritas (Porphyromonas endodontalis, Prophyromonas gingivalis e Prevotella intermedia) e 3 anaeróbias facultativas (enterococcus faecallis, Staphylococcus aureuse e Streptococcus sanguis). Para fins comparativos, testou-se também os efeitos antibacterianos de pastas à base de iodofórmio ou hidróxido de cálcio em glicerina. Os resultados demonstraram que a adição de iodofórmio à pasta H/P/G näo interferiu em sua propriedades antibacterianas. A pasta de hidróxido de cálcio e glicerina não paresentou qualquer efeito inibitório sobre as espécies bacterianas testadas.

Avaliação da atividade antibacteriana de medicação intracanal: três bases fortes e pastas à base de hidróxido de cácio e paramonoclorofenicol canforado / Evaluation of the antibacterial activity of intracanal dressings: three strong bases and pastes containing calcium hydroxide and CMPP

A atividade antibacteriana de três bases fortes e de pastas contendo diferentes proporções de hidróxido de cálcio, óxido de zinco e paramonoclorofenol canforado (PMCC) foi avaliada contra bactérias comumente associadas às infecções endodônticas. A metodologia utilizada foi a difusão em ágar. Foi possível verificar que as bases solúveis (NaOH e KOH) apresentaram efeito inibitório contra todas as cepas, enquanto que o hidróxido de cálcio, uma base pouco solúvel, não foi capaz de inibir o crescimento bacteriano. Das pastas testadas, quanto maior a quantidade de PMCC adicionado, maior a eficácia antibacteriana. Com base neste e em outros estudos, os autores levantam a hipótese de que, pelo menos do ponto de vista da atividade antibacteriana, o hidróxido de cálcio serve como um veículo para o PMCC, permitindo uma liberação lenta e gradual de PMC suficiente para ter atividade antibacteriana e ser biocompatível .