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Abstract Antimicrobial resistance is a worldwide health problem and patients in intensive care are more vulnerable, requiring strict control measures and early identification. Currently, clinical culture materials are used to identify the bacterial agent, but saliva culture is not validated, which has great clinical relevance because it participates in several pathophysiological processes. The aim of this study was to validate saliva culture in an intensive care unit environment, determining its diagnostic value for infection. For this purpose, the results of the 39-month surveillance cultures, from the database of a private hospital were evaluated. A total of 323 cultures were paired between saliva, tracheal secretions, blood and urine from patients who were hospitalized for more than 5 days. The search for correlations between the results was performed using the Spearman correlation test. Severity and evolution data were also correlated. It was possible to correlate the presence of Klebsiella spp. between blood culture and saliva culture in 25% of the results (r = 0.01) and the correlation between saliva and tracheal secretion was 33% (r = 0.33447) with p

This study aimed to evaluate the effects of sodium hypochlorite (NaOCl), chlorhexidine (CHX), and the glycolic extract of propolis (GEP) as endodontic irrigants and of calcium hydroxide [Ca(OH)2], CHX, or Ca(OH)2 + CHX as intracanal medications on the capacity of the lipoteichoic acid (LTA) of Enterococcus faecalis in macrophages’ proinflammatory cytokines production. Freshly extracted 108 human single-rooted teeth were used in this study. The LTA of E. faecalis was standardized in double-distilled pyrogen-free water (250 µg/mL) and inoculated into the specimens subdivided into nine subgroups (n = 12). Cultures of murine macrophages (RAW 264.7) were treated with 30 µL of each sample collected from root canals and incubated (37 °C, 5% CO2) for 24 h. Lastly, anti-TNF-α, anti-IL-6, anti-IP-10, anti-MIP-1α, anti-G-CSF, and anti-IL-1β DuoSet kits were used to perform an ELISA assay. Data were analyzed using one-way ANOVA and Tukey test (p ≥ 0.05). It was found that 1% NaOCl was the most effective irrigant in reducing the capacity of LTA in cytokines production, followed by 12% GEP and 2% CHX, respectively. Ca(OH)2 + CHX presented the best results when associated with NaOCl or GEP. Thus, NaOCl or GEP associated with Ca(OH)2 + CHX were effective in reducing the capacity of LTA in different macrophages pro-inflammatory cytokines production.

Staphylococcus aureus and Acinetobacter baumannii are opportunistic pathogens, and both are involved in different oral infections. This work aimed to analyze the phytochemical composition of Myrciaria cauliflora hydroethanolic extract and to evaluate its antimicrobial and antibiofilm action against Staphylococcus aureus (ATCC 6538) and Acinetobacter baumannii (ATCC 19606; multi-resistant clinical strains 58004, 50098, 566006, and H557). Myrciaria cauliflora hydroethanolic extract was prepared, and the content of soluble solids, flavonoids, and phenols was quantified. High-performance liquid chromatography (HPLC) was performed later. The minimum inhibitory concentration was determined using the broth microdilution method according to the Clinical and Laboratory Standards Institute, standard M7-A6, and subsequently, its minimum bactericidal concentration was determined. Then, the most effective concentrations were analyzed against biofilms. Statistical analysis was performed using the ANOVA method with Tukey’s test. The soluble solids content in the prepared hydroethanolic extract of M. cauliflora was 2.22%. Additionally, the total flavonoid content, measured using the quercetin standard curve, was 0.040 mg/mL. Furthermore, the total phenol content, determined using the gallic acid standard curve, was 0.729 mg/mL. HPLC analysis presented peaks of gallic acid (11.80 m), p-coumaric acid (12.09 m), cinnamic acid derivative (19.02 m), and ellagic acid (29.83 m). The extract demonstrated antimicrobial and antibiofilm action against all tested strains. However, the most effective antibacterial concentration against all the tested bacteria was 5.55 mg/mL. Therefore, these chemical components justify that M. cauliflora hydroethanolic extract is effective in reducing biofilm formation in S. aureus (standard strain) and A. baumannii (standard and clinical strains).

The World Health Organization (WHO) has prioritized developing new drugs against specific bacteria and fungi, such as Enterobacteriaceae and Candida spp. While Pfaffia paniculata is commonly called the “cure-everything”, its scientifically proven benefits are limited to anti-inflammatory and antioxidant actions. Therefore, this study aims to determine the spectrum of antimicrobial activity of Pfaffia paniculata and assess its cytotoxicity. Thus, broth microdilution test was conducted according to the CLSI M7-A9 and M27-A3 reference methods. After screening, microbial species with minimum inhibitory concentration (MIC) values were selected for biofilm tests. These tests evaluated biomass using the crystal violet (CV) test, metabolic activity using the MTT assay, and structural analysis via Scanning Electron Microscopy (SEM). Cytotoxicity was evaluated in human gingival fibroblasts (FMM-1). There were reductions of 29.4 and 42.7% in CV and MTT assays for Candida spp. biofilm. S. mutans and P. aeruginosa biofilms showed a decrease of 15.7 and 28.6%, respectively. Cell viability tests indicated 55.1, 56.9, and 65.5% of viability after contact with 1.93, 0.96, and 0.48 mg/mL of the extract, respectively. The P. paniculata extract showed antimicrobial action, displayed MIC values, and antibiofilm action on P. aeruginosa, S. mutans, and C. albicans. The cytotoxicity on the FMM-1 cell line was dose-dependent. Therefore, P. paniculata extract holds significant potential for developing new drugs.

(1) Background: In hospitals, medical and dental clinics, antiseptics or disinfectants play an essential role in the control of nosocomial infections. This study aimed to evaluate R. officinalis and P. paniculata glycolic extracts regarding: (I) their antimicrobial action on planktonic and biofilm (monotypic and cutaneous biofilm model—S. aureus, S. epidermidis and C. acnes); and (II) their cytotoxicity on human keratinocytes (HaCaT). (2) Methods: Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were performed (CLSI protocol M7-A6 and M11-A8). MTT analysis was used to evaluate the antibiofilm activity of the extracts on biofilms and their cytotoxicity on human keratinocytes. (3) Results: The combined glycolic extracts MIX A (75% P. paniculata + 25% R. officinalis); MIX B (50% P. paniculata + 50% R. officinalis); and MIX C (25% P. paniculata + 75% R. officinalis) promoted MBC values by 50 mg/mL on S. aureus, absent on S. epidermidis, and ranged 6.25–50 mg/mL for C. acnes. The cutaneous biofilm model was reduced more than 90%. In addition, it showed biocompatibility with human keratinocytes, resulting in percentages of viability greater than 50%. (4) Conclusions: The combination of extracts promoted antimicrobial action on planktonic cultures, and monotypic and heterotypic biofilms of skin pathogens. Additionally, these extracts are biocompatible against human keratinocytes.

Candida albicans can cause various types of oral infections, mainly associated with denture stomatitis. Conventional therapy has been linked to high recurrence, toxicity, and fungal resistance, necessitating the search for new drugs and delivery systems. In this study, caffeic acid phenethyl ester (CAPE) and gellan gum (GG) were studied as an antifungal agent and carrier system, respectively. First, we observed that different GG formulations (0.6 to 1.0% wt/vol) were able to incorporate and release CAPE, reaching a controlled and prolonged release over 180 min at 1.0% of GG. CAPE-GG formulations exhibited antifungal activity at CAPE concentrations ranging from 128 to >512 µg/mL. Furthermore, CAPE-GG formulations significantly decreased the fungal viability of C. albicans biofilms at short times (12 h), mainly at 1.0% of GG (p < 0.001). C. albicans protease activity was also reduced after 12 h of treatment with CAPE-GG formulations (p < 0.001). Importantly, CAPE was not cytotoxic to human keratinocytes, and CAPE-GG formulations at 1.0% decreased the fungal burden (p = 0.0087) and suppressed inflammation in a rat model of denture stomatitis. Altogether, these results indicate that GG is a promising delivery system for CAPE, showing effective activity against C. albicans and potential to be used in the treatment of denture stomatitis.

Abstract This study was performed to evaluate the biocompatibility and antifungal effect of Rosmarinus officinalis against Candida albicans in Galleria mellonella model. Five different concentrations of R. officinalis glycolic extract (50; 25; 12.5 e 6.25 mg/mL) were used to evaluate its biocompatibility in G. mellonella model, in which the nystatin suspension (100; 50; 25; 12.5 e 6.25%) was used as a control group. The antifungal action of R. officinalis glycolic extract was evaluated on C. albicans for 72, 48 and 12 h at two different phases: (1) using the extract as therapeutic agent; and (2) using the extract as prophylactic agent. PBS was used as a negative control group. G. mellonella survival curves were plotted using the Kaplan–Meier method and statistical analysis was performed using the log-rank test (Mantel–Cox) and the significance level was set at (α ≤ 0.05). There was no significant difference among the groups in which all were biocompatible except of a significant death rate of 26.6% with nystatin 100%. In phase 1, it was found that after 7 days, there was no statistically significant difference among the prophylactic treatment groups. In phase 2, the groups of R. officinalis 6.25 mg/mL for 72 h and R. officinalis of 12.5 mg/mL for 24 h promoted the survival rate of the larvae in comparison with the control group with a significant difference (p = 0.017) and (p = 0.032) respectively. Therefore, R. officinalis extract is biocompatible in different concentrations and can be used as a prophylactic agent against fungal infection.

Abstract Calcium silicate-based cements have diverse applications in endodontics. This study aimed to evaluate the antibiofilm action, biocompatibility, morphological structure, chemical composition and radiopacity of Five Mineral Oxides (5MO), Mineral Trioxide Aggregate Repair High Plasticity (MTA Repair HP), and Mineral Trioxide Aggregate (MTA) cements. MTT analysis was used to test the antibiofilm action of these cements against five anaerobic microorganisms, and test their biocompatibility with mouse macrophage (RAW 264.7) and osteoblasts (MG-63) cultures. Their morphological structure and chemical composition were evaluated by scanning electron microscopy (SEM) coupled to energy dispersion X-ray spectroscopy (EDX), and the phase analysis was performed by X-ray diffraction (XRD). Conventional radiography was used to assess the radiopacity of the cements. 5MO, MTA Repair HP and MTA were effective against Porphyromonas gingivalis, Parvimonas micra, Fusobacterium nucleatum and Prevotella intermedia, they were biocompatible with macrophages and osteoblasts after 5 min of contact, and they had adequate radiopacity to be used clinically. Bismuth oxide (Bi2O3) is used as a radiopacifier in MTA and 5MO, and calcium tungstate, in MTA Repair HP. Titanium dioxide (TiO2) (ANATASE) is responsible for the antimicrobial action and biocompatibility of 5MO.

The accumulated dental biofilm can be a source of oral bacteria that are aspirated into the lower respiratory tract causing ventilator-associated pneumonia in hospitalized patients. The aim of this study was to evaluate the synergistic antibiofilm action of the produced and phytochemically characterized extracts of Cinnamomum verum and Brazilian green propolis (BGP) hydroethanolic extracts against multidrug-resistant clinical strains of Acinetobacter baumannii and Pseudomonas aeruginosa, in addition to their biocompatibility on human keratinocyte cell lines (HaCaT). For this, High-performance liquid chromatography analysis of the plant extracts was performed; then the minimum inhibitory and minimum bactericidal concentrations of the extracts were determined; and antibiofilm activity was evaluated with MTT assay to prevent biofilm formation and to reduce the mature biofilms. The cytotoxicity of the extracts was verified using the MTT colorimetric test, evaluating the cellular enzymatic activity. The data were analyzed with one-way ANOVA and Tukey’s tests as well as Kruskal–Wallis and Dunn’s tests, considering a significance level of 5%. It was possible to identify the cinnamic aldehyde in C. verum and p-coumaric, caffeic, and caffeoylquinic acids as well as flavonoids such as kaempferol and kaempferide and Artepillin-C in BGP. The combined extracts were effective in preventing biofilm formation and reducing the mature biofilms of A. baumannii and P. aeruginosa. Moreover, both extracts were biocompatible in different concentrations. Therefore, C. verum and BGP hydroethanolic extracts have bactericidal and antibiofilm action against multidrug resistant strains of A. baumannii and P. aeruginosa. In addition, the combined extracts were capable of expressively inhibiting the formation of A. baumannii and P. aeruginosa biofilms (prophylactic effect) acting similarly to 0.12% chlorhexidine gluconate.

Candida spp. cause fungal infection that affects patients’ oral health. This study aimed to evaluate the isolated and synergistic antifungal effect of Rosa centifolia L., Curcuma longa L., Rosmarinus officinalis L., and Punica granatum L. glycolic extracts against Candida albicans, Candida dubliniensis, Candida tropicalis, and Candida krusei planktonic and biofilm forms. The plant extracts were chemically characterized and the main compounds were quantified by high-performance liquid chromatography (HPLC-DAD) analysis. The minimum inhibitory and minimum fungicidal concentrations of the extracts were determined, and antibiofilm activity was evaluated by MTT assay. Data were analyzed by one-way ANOVA and Tukey’s tests, and by Kruskal–Wallis and Dunn’s tests, considering a significance level of 5%. The main compounds identified in each of the extracts were: p-coumaric acid (2153.22 μg/100 mL) in the rosemary extract, gallotannins (4318.31 μg/100 mL) in the pomegranate extract, quercetin derivatives (3316.50 μg/100 mL) in the extract of white roses, and curcumin (135.09 μg/100 mL) in the turmeric extract. The combination of R. centifolia and C. longa glycolic extracts was effective against C. albicans, C. dubliniensis, and C. tropicalis biofilms over different periods (p < 0.05). The combination of R. officinalis and P. granatum glycolic extracts was effective against C. albicans and C. krusei biofilms after 30 min, and against C. tropicalis after 24 h, with all combinations showing an average reduction of 50% in cell viability (p < 0.05). In conclusion, the combined plant extracts have antifungal and antibiofilm action against Candida spp. in different concentrations and times of action.

Abstract Background An effective biomaterial for bone replacement should have properties to avoid bacterial contamination and promote bone formation while inducing rapid cell differentiation simultaneously. Bone marrow stem cells are currently being investigated because of their known potential for differentiation in osteoblast lineage. This makes these cells a good option for stem cell-based therapy. We have aimed to analyze, in vitro, the potential of pure titanium (Ti), Ti-35Nb-7Zr alloy (A), niobium (Nb), and zirconia (Zr) to avoid the microorganisms S. aureus (S.a) and P. aeruginosa (P.a). Furthermore, our objective was to evaluate if the basic elements of Ti-35Nb-7Zr alloy have any influence on bone marrow stromal cells, the source of stem cells, and observe if these metals have properties to induce cell differentiation into osteoblasts. Methods Bone marrow stromal cells (BMSC) were obtained from mice femurs and cultured in osteogenic media without dexamethasone as an external source of cell differentiation. The samples were divided into Ti-35Nb-7Zr alloy (A), pure titanium (Ti), Nb (niobium), and Zr (zirconia) and were characterized by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). After predetermined periods, cell interaction, cytotoxicity, proliferation, and cell differentiation tests were performed. For monotypic biofilm formation, standardized suspensions (106 cells/ml) with the microorganisms S. aureus (S.a) and P. aeruginosa (P.a) were cultured for 24 h on the samples and submitted to an MTT test. Results All samples presented cell proliferation, growth, and spreading. All groups presented cell viability above 70%, but the alloy (A) showed better results, with statistical differences from Nb and Zr samples. Zr expressed higher ALP activity and was statistically different from the other groups (p < 0.05). In contrast, no statistical difference was observed between the samples as regards mineralization nodules. Lower biofilm formation of S.a and P.a. was observed on the Nb samples, with statistical differences from the other samples. Conclusion Our results suggest that the basic elements present in the alloy have osteoinductive characteristics, and Zr has a good influence on bone marrow stromal cell differentiation. We also believe that Nb has the best potential for reducing the formation of microbial biofilms.

Radiotherapy induces a higher level of Candida spp. colonization, resulting in oral candidiasis. This study aimed to evaluate the phototransformation potential of the glycolic extract of Curcuma longa (C. longa); the antifungal activity of C. longa, curcumin, and antifungal photodynamic therapy (aPDT) with blue light-emitting diodes “LED” on Candida albicans and Candida tropicalis in vitro; and the toxicity of C. longa and curcumin in Galleria mellonella model. In order to confirm the light absorption capacity of the C. longa extract, its phototransformation potential was evaluated. The antifungal effect of C. longa, curcumin, and aPDT was evaluated over Candida spp. Finally, the toxicity of C. longa and curcumin was evaluated on the Galleria mellonella model. The data were analyzed using the GraphPad Prism 5.0 software considering α = 5%. It was found that C. longa, curcumin, and aPDT using blue LED have an antifungal effect over C. albicans and C. tropicalis. The extract of C. longa 100 mg/mL and curcumin 200 μg/mL do not show toxicity on Galleria mellonella model.

Green propolis may represent a promising therapeutic alternative against dental anaerobic pathogens because of its antimicrobial action. This study aimed to evaluate the antimicrobial and antibiofilm actions of Brazilian green propolis aqueous extract (BGP-AqExt) against dental anaerobic bacteria. The minimum inhibitory concentration (MIC) and minimum microbicide concentration (MMC) of the extract were determined against the standard strains (ATCC) of Fusobacterium nucleatum, Parvimonas micra, Prevotella intermedia, Porphyromonas gingivalis and Porphyromonas endodontalis. BGP-AqExt was chemically characterized by high-performance liquid chromatography with diode-array detection (HPLC-DAD) analysis. Antibiofilm action was measured by MTT and crystal violet tests. The data were statistically analyzed by ANOVA and Tukey (5%) tests. The extract had antimicrobial action against all tested anaerobic bacteria, with an MIC value of 55 mg/mL for all bacteria, an MMC of 27.5 mg/mL for F. nucleatum and P. micra and 55 mg/mL for P. intermedia. Chemically, BGP-AqExt is composed of quercetin, gallic acid, caffeic and p-coumaric acid, drupani, kaempferol and Artepillin C. Significant reductions in biomass and metabolic action of biofilms were found after BGP-AqExt application. Therefore, BGP-AqExt has an antimicrobial and antibiofilm effect against dental anaerobic bacteria.

Abstract Rosmarinus officinalis L. (rosemary) is a medicinal plant native to the Mediterranean region and cultivated around the world. Besides the therapeutic purpose, it is commonly used as a condiment and food preservative. R. officinalis L. is constituted by bioactive molecules, the phytocompounds, responsible for implement several pharmacological activities, such as anti-inflammatory, antioxidant, antimicrobial, antiproliferative, antitumor and protective, inhibitory and attenuating activities. Thus, in vivo and in vitro studies were presented in this Review, approaching the therapeutic and prophylactic effects of R. officinalis L. on some physiological disorders caused by biochemical, chemical or biological agents. In this way, methodology, mechanisms, results, and conclusions were described. The main objective of this study was showing that plant products could be equivalent to the available medicines.

This study aimed to evaluate the efficacy of passive ultrasonic irrigation (PUI) on dissolving the organic tissue inside simulated internal root resorption (IRR) using sodium hypochlorite (NaOCl) or chlorhexidine (CHX). A total of 40 human lower premolars were collected based on dimensional and morphological similarities. The roots were embedded in cylinders (3 cm diameter; 2.5 cm height) of self-cured acrylic resin, and then an IRR was simulated. The specimens were divided into 4 groups (n = 10) according to irrigation protocols: group 1: CHX + PUI; group 2: CHX; group 3: NaOCl + PUI; group 4: NaOCl. The total irrigation time was 150 s at a flow rate of 5 mL/min. A tissue mass of porcine palatine mucosa was used to simulate the organic tissue, it was weighed before and after the irrigation using an analytic balance, and the difference between both readings was calculated and transferred to percentage values. Data were submitted to statistical analysis using two-way ANOVA (factors: irrigant type and with/without PUI) and Tukey’s test for multiple comparisons among the experimental groups (α = 0.05). There was a significant difference in both factors (irrigant: p=0.04; PUI: p≤0.001). The groups that used PUI were more effective in dissolving the organic tissue of the IRR simulation than the groups without PUI. PUI is more effective than the syringe and needle irrigation in organic tissue dissolution.

Background: Sodium hypochlorite (NaOCl) is the most commonly used irrigant in endodontics. The purpose of this study was to evaluate the effect of NaOCl solution (2.5%) and gel (3%) with/without passive ultrasonic irrigation (PUI) on Enterococcus faecalis, Escherichia coli, and their endotoxins, lipopolysaccharide (LPS) and lipoteichoic acid (LTA). Methods: 40 human lower premolars were contaminated with E. coli (ATCC 25922) for 28 days and E. faecalis (ATCC 29212) for 21 days. Specimens were randomly divided into four groups: (1) 2.5% NaOCl irrigating the canals without PUI activation; (2) 2.5% NaOCl with PUI; (3) 3% NaOCl gel irrigating the canals without PUI; and (4) 3% NaOCl gel with PUI. 40 mL of irrigant was used for each group. PUI activation was carried out using E1-Irrisonic stainless-steel tip at 10% frequency. After treatment, all specimens were filled with 3mL of 17% ethylenediaminetetraacetic acid (EDTA) for 3min and then washed with nonpyrogenic saline solution. Three samples were collected from the canals: S1, at baseline to confirm biofilm formation; S2 after treatment; and S3 after EDTA. Samples were assessed for E. coli and E. faecalis colony forming units, and LPS and LTA were assessed using chromogenic kinetic LAL assay and ELISA, respectively. Data were analyzed by Kruskal-Wallis, Friedmann and Dunn tests with α≤0.05. Results: All groups were effective in reducing the microbial load of E. coli and E. faecalis after treatment without a significant difference among the groups. NaOCl and NaOCl gel groups had no significant difference in reducing LPS and LTA. Statistically increased reduction was seen for NaOCL + PUI and NaOCl gel + PUI compared for groups without PUI. Conclusions: NaOCl gel has the same antimicrobial action of NaOCl solution and can partially detoxify endotoxins. PUI improves NaOCl (gel or solution) action over E. faecalis and E. coli and their endotoxins.

Produtos naturais, como extratos glicólicos de plantas, são importantes para a aplicação clínica na área da saúde, como em enxaguatórios bucais, cremes dentais e irrigação intracanal. Assim é necessário realizar estudos de citotoxicidade desses extratos glicólicos. O presente estudo buscou avaliar a atividade citotóxica dos extratos glicólicos de Cynara scolymus L. (alcachofra), Myracrodruom urundeuva Allem. (aroeira-do-sertão-do-sertão) e Camellia sinensis (L.) Kuntze (chá verde) em macrófagos de camundongo (RAW 264.7) pelo teste de atividade metabólica MTT. Para tanto, as células foram distribuídas em microplacas de 96 poços e foram expostas a 11 diluições seriadas de cada extrato (200 mg/mL,100 mg/mL, 50 mg/mL, 25 mg/mL, 12,5 mg/mL, 6,25 mg/mL, 3,13 mg/mL, 1,56 mg/mL, 0,78 mg/mL, 0,39 mg/mL e 0,20 mg/mL), sendo n=8 para cada diluição. Após o tempo de contato de 5 minutos e 24 horas, foi avaliada a viabilidade celular utilizando o teste MTT. Diante destes resultados, no tempo de exposição de 5 minutos com os extratos, em ordem crescente de redução da viabilidade celular, seguiram-se o chá verde, com aumento da viabilidade celular, a aroeira-do-sertão e o extrato de alcachofra. Por meio do MTT dos três extratos por tempo de exposição de 24 horas, observou-se que o extrato de alcachofra apresentou maior toxicidade, seguido do extrato de chá verde e aroeira-do-sertão. A análise estatística foi realizada por ANOVA e teste de Tukey, com significância de 5%. Conclusões: Entre os extratos, o chá verde com 12,5mg/mL, com interessantes 5 minutos e 24 horas, despertou atenção, pois foi a maior concentração e não apresentou citotoxicidade para os macrófagos, assim como a alcachofra que foi a mais citotóxica para os macrófagos, em ambos os tempos (5 min e 24 h).

Thymol is a phytocompound present in many plants and several biological effects have been reported, such as antimicrobial effect. However, the biocompatibility of this plant product should be checked. Thereby, the action of thymol was evaluated in C. albicans, S. aureus, and S. mutans, as well as in murine macrophages (RAW 264.7). Firstly, the effect of thymol was analyzed in planktonic cultures of microorganisms and the most effective concentration was evaluated in biofilms. Cytotoxicity, quantification of TNF-α and genotoxicity were checked. The results were analyzed by T-Test or ANOVA and Tukey's Test (P ≤ .05). Thymol provided inhibitory and microbicidal effects for planktonic cultures and reduction of biofilms. High concentrations affected the viability of RAW 264.7. Production of TNF-α and frequency of micronuclei were similar to the control group. Thus, thymol showed antimicrobial effect, biocompatibility in some concentrations and absence of genotoxicity.

Chronic alcohol exposure can affect the osteoblastic activity and the proliferation and differentiation of cells due to its toxic effect, which can affect negatively bone repair and bone microarchitecture. The aim of this study was to evaluate the effects of chronic use of 20% alcohol on rats regarding osteoblastic differentiation, extrinsic and intrinsic properties of the tibia, and hepatic and renal morphology. Wistar rats were divided into three groups (n=9) in accordance with a 24-week diet. After euthanasia, kidneys, liver, and tibias were removed for analysis and femurs mesenchymal cells were collected. The results showed that chronic use of 20% alcohol influenced neither the alkaline phosphatase production nor total protein (p>0.05) in rats, with similar formation of nodules in all groups (p>0.05). However, significant changes in the liver and kidneys and adverse effects on the mechanical properties of the tibia were observed. According to the results, it can be concluded that the chronic use of alcohol for 24 weeks had no negative influence on the activity and differentiation of osteoblasts, but the mechanical properties of the tibia were impaired and the organs responsible for metabolism and excretion were also affected due to the consumption of alcohol.

ABSTRACT BACKGROUND: A high-quality electronic search is essential for ensuring accuracy and comprehensiveness among the records retrieved when conducting systematic reviews. Therefore, we aimed to identify the most efficient method for searching in both MEDLINE (through PubMed) and EMBASE, covering search terms with variant spellings, direct and indirect orders, and associations with MeSH and EMTREE terms (or lack thereof). DESIGN AND SETTING: Experimental study. UNESP, Brazil. METHODS: We selected and analyzed 37 search strategies that had specifically been developed for the field of anesthesiology. These search strategies were adapted in order to cover all potentially relevant search terms, with regard to variant spellings and direct and indirect orders, in the most efficient manner. RESULTS: When the strategies included variant spellings and direct and indirect orders, these adapted versions of the search strategies selected retrieved the same number of search results in MEDLINE (mean of 61.3%) and a higher number in EMBASE (mean of 63.9%) in the sample analyzed. The numbers of results retrieved through the searches analyzed here were not identical with and without associated use of MeSH and EMTREE terms. However, association of these terms from both controlled vocabularies retrieved a larger number of records than did the use of either one of them. CONCLUSIONS: In view of these results, we recommend that the search terms used should include both preferred and non-preferred terms (i.e. variant spellings and direct/indirect order of the same term) and associated MeSH and EMTREE terms, in order to develop highly-sensitive search strategies for systematic reviews.

Titanium (Ti) and Ti-6 Aluminium-4 Vanadium alloys are the most common materials in implants composition but β type alloys are promising biomaterials because they present better mechanical properties. Besides the composition of biomaterial, many factors influence the performance of the biomaterial. For example, porous surface may modify the functional cellular response and accelerate osseointegration. This paper presents in vitro and in vivo evaluations of powder metallurgy-processed porous samples composed by different titanium alloys and pure Ti, aiming to show their potential for biomedical applications. The porous surfaces samples were produced with different designs to in vitro and in vivo tests. Samples were characterized with scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and elastic modulus analyses. Osteogenic cells from newborn rat calvaria were plated on discs of different materials: G1-commercially pure Ti group (CpTi); G2-Ti-6Al-4V alloy; G3-Ti-13 Niobium-13 Zirconium alloy; G4-Ti-35 Niobium alloy; G5-Ti-35 Niobium-7 Zirconium-5 Tantalum alloy. Cell adhesion and viability, total protein content, alkaline phosphatase activity, mineralization nodules and gene expression (alkaline phosphatase, Runx-2, osteocalcin and osteopontin) were assessed. After 2 and 4 weeks of implantation in rabbit tibia, bone ingrowth was analyzed using micro-computed tomography (μCT). EDS analysis confirmed the material production of each group. Metallographic and SEM analysis revealed interconnected pores, with mean pore size of 99,5μm and mean porosity of 42%, without significant difference among the groups (p>0.05). The elastic modulus values did not exhibit difference among the groups (p>0.05). Experimental alloys demonstrated better results than CpTi and Ti-6Al-4V, in gene expression and cytokines analysis, especially in early experimental periods. In conclusion, our data suggests that the experimental alloys can be used for biomedical application since they contributed to excellent cellular behavior and osseointegration besides presenting lower elastic modulus.

Alcachofra é um vegetal utilizado na culinária e algumas de suas ações biológicas foram descritas, como ação antioxidante e anti-inflamatória, porém foi pouco relatada sua atividade sobre micro-organismos. Com isso, o objetivo do presente estudo foi verificar o efeito antimicrobiano do extrato de alcachofra sobre P. aeruginosa. Primeiramente, foi verificada a ação deste extrato sobre cultura planctônica, pelo método de microdiluição em caldo (50 a 0,09 mg/mL), em seguida, sobre biofilme formado por 48 h em poços de placas de microtitulação, com exposição de 5 min ao extrato de alcachofra (200 mg/mL). Solução salina 0,9% e clorexidina 0,12% foram utilizadas como controles. As reduções do biofilme foram verificadas pelo teste de MTT e analisadas estatisticamente por ANOVA e Tukey Test (p ≤ 0,05). Em culturas planctônicas foi verificado que as concentrações avaliadas não foram efetivas (CIM > 50 mg/mL), contudo, sobre o biofilme foi verificada redução significativa de 42 ± 16%. Desta forma, pode-se concluir que o extrato de alcachofra apresentou efeito antimicrobiano sobre biofilme de P. aeruginosa.

É de grande importância ampliar as pesquisas científicas com plantas medicinais sobre micro-organismos. Foi verificado o efeito antimicrobiano do extrato de C. sinensis , sobre cultura planctônica e biofilme de S. aureus. Neste estudo foi verificada ação do extrato entre 50 a 0,09 mg/mL sobre cultura planctônica, para determinação da CIM e CBM. A ação do extrato sobre biofilme foi analisada pela exposição de 5 min ao produto vegetal a 200mg/mL. Foi utilizado o método de MTT para determinar a redução da viabilidade do biofilme. Nos grupos controles foram utilizadas clorexidina (+) e solução salina (-), sendo n = 12/grupo. A redução do biofilme foi analisada por ANOVA e Tukey Test (p ≤ 0,05). Em cultura planctônica as concentrações avaliadas não foram efetivas, contudo, utilizando-se a concentração de 200 mg/mL sobre o biofilme, foi verificada redução significativa. Com isso, concluiu-se que o extrato de chá verde demonstrou ação sobre biofilme de S. aureus provendo redução significativa em sua viabilidade.

As folhas de tomilho são utilizadas como condimento, conservante alimentício e para fins medicinais. O objetivo desse estudo foi avaliar a ação antimicrobiana do extrato de tomilho sobre biofilme composto por C. albicans e S. mutans. Para tanto, suspensões de cada micro-organismo foram ajustadas a 107 UFC/mL e adicionadas (100 µL/poço de cada) em placa de microtitulação. Após 90 min de incubação, o sobrenadante foi substituído por 200 µL/poço de BHI+YNB (1:1). O biofilme de 48 h foi exposto por 5 min ao extrato de tomilho ou à solução salina. Após lavagens com salina, 100 µL/poço de solução de MTT foi adicionada e incubada por 1 h, esta solução foi substituída por dimetilsulfóxido (100 µL/poço) e a placa foi incubada por mais 10 min e agitada por outros 10 min. Os valores de densidade óptica (DO) foram obtidos em λ = 570nm e convertidos em percentual de viabilidade, analisados estatisticamente por T-Test (p ≤ 0,05). O extrato de tomilho reduziu significativamente a viabilidade do biofilme polimicrobiano (64 ± 11%). Com isso, foi constatado o efeito antimicrobiano do extrato de tomilho sobre o biofilme composto por C. albicans e S. mutans.

Adhesion and colonization of the oral cavity by Candida albicans is an initial step in candidosis. Orthodontic and other oral appliances seem to favor candidal presence. The aim of this work was to compare the presence of Candida species in saliva, their adherence to oral epithelial cells, and the levels of anti-C. albicans IgA in children with or without orthodontic appliances. This study included 30 children 5 to 12 years old (9.1 ± 1.7 years old) who were users of removable orthodontic devices for at least 6 months and 30 control children of similar ages (7.7 ± 1.5 years old). The presence of yeast species in the saliva was evaluated by microbiological methods. Candida species were identified using phenotypic methods. Anti-C. albicans IgA levels in saliva were analyzed by ELISA. The yeasts adhering to oral epithelial cells were assessed by exfoliative cytology. No statistically significant differences were observed for saliva yeast counts and anti-C. albicans IgA levels between the studied groups. Children with orthodontic devices exhibited more yeast cells adhering to oral epithelial cells and a higher percentage of non-albicans species relative to the control group. In conclusion, orthodontic appliances may favor the adherence of Candida to epithelial cells but do not influence the presence of these yeasts in saliva, and the levels of anti-C. albicans IgA do not correlate with yeast adherence or presence of Candida in the oral cavity

Objective: The aim of this study was to evaluate the antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecalis inoculated in root canals. Material and Methods: Seventy-two human tooth roots were contaminated with C. albicans and E. faecalis for 21 days. The groups were divided according to the auxiliary chemical substance into: G1) 2.5% sodium hypochlorite (NaOCl), G2) 2% chlorhexidine gel (CHX), G3) castor oil, G4) glycolic Aloe vera extract, G5) glycolic ginger extract, and G6) sterile saline (control). The samples of the root canal were collected at different intervals: confirmation collection, at 21 days after contamination; 1st collection, after instrumentation; and 2nd collection, seven days after instrumentation. Microbiological samples were grown in culture medium and incubated at 37°C for 48 hours. Results: The results were submitted to the Kruskal-Wallis and Dunn (5%) statistical tests. NaOCl and CHX completely eliminated the microorganisms of the root canals. Castor oil and ginger significantly reduced the number of CFU of the tested bacteria. Reduction of CFU/mL at the 1st and 2nd collections for groups G1, G2, G3 and G4 was greater in comparison to groups G5 and G6. Conclusion: It was concluded that 2.5% sodium hypochlorite and 2% chlorhexidine gel were more effective in eliminating C. albicans and E. faecalis, followed by the castor oil and glycolic ginger extract. The Aloe vera extract showed no antimicrobial activity.

The purpose of this study was to evaluate the effectiveness of glycolic propolis (PRO) and ginger (GIN) extracts, calcium hydroxide (CH), chlorhexidine (CLX) gel and their combinations as ICMs (ICMs) against Candida albicans, Enterococcus faecalis, Escherichia coli and endotoxins in root canals. Material and Methods After 28 days of contamination with microorganisms, the canals were instrumented and then divided according to the ICM: CH+saline; CLX, CH+CLX, PRO, PRO+CH; GIN; GIN+CH; saline. The antimicrobial activity and quantification of endotoxins by the chromogenic test of Limulus amebocyte lysate were evaluated after contamination and instrumentation at 14 days of ICM application and 7 days after ICM removal. Results and Conclusion After analysis of results and application of the Kruskal-Wallis and Dunn statistical tests at 5% significance level, it was concluded that all ICMs were able to eliminate the microorganisms in the root canals and reduce their amount of endotoxins; however, CH was more effective in neutralizing endotoxins and less effective against C. albicans and E. faecalis, requiring the use of medication combinations to obtain higher success.

The purpose of this study was to evaluate the effectiveness of glycolic propolis (PRO) and ginger (GIN) extracts, calcium hydroxide (CH), chlorhexidine (CLX) gel and their combinations as ICMs (ICMs) against Candida albicans, Enterococcus faecalis, Escherichia coli and endotoxins in root canals.Material and MethodsAfter 28 days of contamination with microorganisms, the canals were instrumented and then divided according to the ICM: CH+saline; CLX, CH+CLX, PRO, PRO+CH; GIN; GIN+CH; saline. The antimicrobial activity and quantification of endotoxins by the chromogenic test of Limulus amebocyte lysate were evaluated after contamination and instrumentation at 14 days of ICM application and 7 days after ICM removal.Results and ConclusionAfter analysis of results and application of the Kruskal-Wallis and Dunn statistical tests at 5% significance level, it was concluded that all ICMs were able to eliminate the microorganisms in the root canals and reduce their amount of endotoxins; however, CH was more effective in neutralizing endotoxins and less effective against C. albicans and E. faecalis, requiring the use of medication combinations to obtain higher success.

Due to the increase of bacterial resistance, medicinal alternatives are being explored. Punica granatum L. is an effective herbal extract with broad spectrum of action and bactericidal, antifungal, anthelmintic potential and being able to modulate the immune response. The aim was to evaluate the antimicrobial activity of pomegranate glycolic extract (PGE) against the periodontal pathogen Porphyromonas gingivalis by using Galleria mellonella as in vivo model. Fifteen larvae were used per group. Injection of high concentration (200, 100, and 25 mg/mL) of PGE showed a toxic effect, leading them to death. A suspension of P. gingivalis (106 cells/mL) was inoculated in the left last proleg and PGE (12.5, 6.25, 3.1, and 2.5 mg/mL) were injected into the right proleg. The larvae were then kept at 37°C under the dark. Injection of PGE at any dose statistically improved larvae survival rates. The data were analysed (log-rank test, Mantel-Cox, P

This study evaluated the action of Pfaffia paniculata K., Juglans regia L., and Rosmarius officinalis L. extracts against planktonic form and biofilm of Klebsiella pneumoniae (ATCC 4352). Minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) values were determined for each extract by microdilution broth method, according to Clinical and Laboratory Standards Institute. Next, antimicrobial activity of the extracts on biofilm was analyzed. For this, standardized suspension at 107 UFC/mL of K. pneumoniae was distributed into 96-well microplates (n=10) and after 48 h at 37°C and biofilm was subjected to treatment for 5 min with the extracts at a concentration of 200 mg/mL. ANOVA and Tukey tests (5%) were used to verify statistical significant reduction (p

Due to the increase in life expectancy, new treatments have emerged which, although palliative, provide individuals with a better quality of life. Artificial saliva is a solution that contains substances that moisten a dry mouth, thus mimicking the role of saliva in lubricating the oral cavity and controlling the existing normal oral microbiota. This study aimed to assess the influence of commercially available artificial saliva on biofilm formation by Candida albicans. Artificial saliva I consists of carboxymethylcellulose, while artificial saliva II is composed of glucose oxidase, lactoferrin, lysozyme and lactoperoxidase. A control group used sterile distilled water. Microorganisms from the oral cavity were transferred to Sabouraud Dextrose Agar and incubated at 37°C for 24 hours. Colonies of Candida albicans were suspended in a sterile solution of NaCl 0.9%, and standardisation of the suspension to 106 cells/mL was achieved. The acrylic discs, immersed in artificial saliva and sterile distilled water, were placed in a 24-well plate containing 2 mL of Sabouraud Dextrose Broth plus 5% sucrose and 0.1 mL aliquot of the Candida albicans suspension. The plates were incubated at 37°C for 5 days, the discs were washed in 2 mL of 0.9% NaCl and placed into a tube containing 10 mL of 0.9% NaCl. After decimal dilutions, aliquots of 0.1 mL were seeded on Sabouraud Dextrose Agar and incubated at 37°C for 48 hours. Counts were reported as CFU/mL (Log10). A statistically significant reduction of 29.89% (1.45 CFU/mL) of Candida albicans was observed in saliva I when compared to saliva II (p = 0.002, considering p≤0.05).

OBJECTIVE: The purpose of this study was to evaluate the effcacy of auxiliary chemical substances and intracanal medications on Escherichia coli and its endotoxin in root canals. MATERIAL AND METHODS: Teeth were contaminated with a suspension of E. coli for 14 days and divided into 3 groups according to the auxiliary chemical substance used: G1) 2.5% sodium hypochlorite (NaOCl); G2) 2% chlorhexidine gel (CLX); G3) pyrogenfree solution. After, these groups were subdivided according to the intracanal medication (ICM): A) Calcium hydroxide paste (Calen®), B) polymyxin B, and C) Calcium hydroxide paste+2% CLX gel. For the control group (G4), pyrogen-free saline solution was used without application of intracanal medication. Samples of the root canal content were collected immediately after biomechanical preparation (BMP), at 7 days after BMP, after 14 days of intracanal medication activity, and 7 days after removal of intracanal medication. The following aspects were evaluated for all collections: a) antimicrobial activity; b) quantifcation of endotoxin by the Limulus Amebocyte Lysate test (LAL). Results were analyzed by the Kruskal-Wallis and Dunn's tests at 5% signifcance level. RESULTS: The 2.5% NaOCl and CLX were able to eliminate E. coli from root canal lumen and reduced the amount of endotoxin compared to saline. CONCLUSIONS: It was concluded that 2.5% NaOCl and CLX were effective in eliminating E. coli. Only the studied intracanal medications were to reduce the amount of endotoxin present in the root canals, regardless of the irrigant used.

OBJECTIVE: To evaluate the efficacy of 16% carbamide peroxide gel (CP16%), tetrahydrate sodium perborate (SP) and mixture (CP16% + SP), in walking bleaching of non-vital discolored teeth. MATERIALS AND METHODS: Sixty single-rooted human premolars with intact crowns were used and initial color was assessed using Vita shade guide and standardized photos. The teeth were stained using rabbit fresh blood for 18 days and photos of discolored teeth and color evaluation were performed. The teeth were divided into 4 groups (n= 15), according to bleaching agent used: G1) CP16% gel; G2) CP16% gel + SP; G3) SP + distilled water; G4: control. The bleaching agents were replaced twice at 7-day intervals for 21 days. All teeth were evaluated by two endodontists at days 0, 7, 14 and 21 and the color changes were assessed using Vita shade guide and standardized photos. The results were analyzed by Kruskal-Wallis and Dunn's tests (p=0.05). RESULTS: The experimental groups presented statistically similar bleaching results (p>0.05) at the end of 7, 14 and 21 days. These groups presented significantly higher bleaching efficacy than control group (G4) (p

OBJECTIVE: The purpose of this study was to evaluate the sealing ability of castor oil polymer (COP), mineral trioxide aggregate (MTA) and glass ionomer cement (GIC) as root-end filling materials. Forty-five single-rooted human teeth were cleaned and prepared using a step-back technique. The apical third of each root was resected perpendicularly to the long axis direction. All teeth were obturated with gutta-percha and an endodontic sealer. After, a root-end cavity with 1.25-mm depth was prepared using a diamond bur. The specimens were randomly divided into three experimental groups (n=15), according to the root-end filling material used: G1) COP; G2) MTA; G3) GIC. The external surfaces of the specimens were covered with epoxy adhesive, except the root-end filling. The teeth were immersed in rhodamine B dye for 24 hours. Then, the roots were sectioned longitudinally and the linear dye penetration at the dentin/material interface was determined using a stereomicroscope. ANOVA and Tukey's tests were used to compare the three groups. The G1 group (COP) presented smaller dye penetration, statistically different than the G2 (MTA) and G3 (GIC) groups (p0.05). The results of this study indicate that the COP presented efficient sealing ability when used as a root-end filling material showing results significantly better than MTA and GIC.

This study aimed to evaluate the capacity of Lactobacillus rhamnosus and/or its products to induce the synthesis of cytokines (TNF-α, IL-1β, IL-4, IL-6, IL-10, and IL-12) by mouse macrophages (RAW 264.7). Three microorganism preparations were used: live L. rhamnosus (LLR) suspension, heat-killed L. rhamnosus (HKLR) suspension, and the supernatant of a heat-killed L. rhamnosus (SHKLR) suspension, which were cultured with macrophages (37°C, 5% CO2) for 2 h and 30 min. After that, cells were cultured for 16 h. The supernatants were used for the quantitation of cytokines, by ELISA. The results were compared with the synthesis induced by lipopolysaccharide (LPS) and analysed, using ANOVA and Tukey test, 5%. LLR and HKLR groups were able to significantly increase the production of TNF-α, IL-6, and IL-10 (P0.05). All the L. rhamnosus suspensions were not able to produce detectable levels of IL-1β or significant levels of IL-4 and IL-12 (P>0.05). In conclusion, live and heat-killed L. rhamnosus suspensions were able to induce the synthesis of different cytokines with proinflammatory (TNF-α and IL-6) or regulatory (IL-10) functions, suggesting the role of strain L. rhamnosus ATCC 7469 in the modulation or in the stimulation of immune responses.

The aim of this study was to evaluate in vitro the antimicrobial activity of glass ionomer (GIC) and zinc oxide-eugenol (ZOE) cements against Candida albicans. Standardized GIC and ZOE specimens were maintained in contact with C. albicans suspension (1 ´ 10(6) cells/ml) at 37°C for 24 h, 48 h or 7 days. A control group without any testing cement was included. After the incubation period, aliquots of 0.1 ml were plated on Sabouraud's agar, and then the number of colonies was counted. The results were expressed as values of logarithms of colony-forming units per milliliter (log CFU/mL) and were analyzed statistically by Kruskal-Wallis ANOVA. After 48 h of incubation, the ZOE group presented no growth of C. albicans. GIC and control groups presented similar mean values at all tested periods. According to the results obtained, it could be concluded that, under the experimental conditions, ZOE cement was more effective in vitro against C. albicans than GIC.O objetivo deste estudo foi avaliar in vitro a atividade antimicrobiana dos cimentos de ionômero de vidro (CIV) e óxido de zinco e eugenol (OZE) sobre Candida albicans. Corpos-de-prova padronizados de CIV e OZE foram mantidos em contato com suspensão (1 ´ 10(6) células/ml) de C. albicans a 37°C por 24 horas, 48 horas ou 7 dias. Um grupo controle sem nenhum cimento teste foi incluído. Após o período de incubação, alíquotas de 0,1 ml foram semeadas em ágar Sabouraud e o número de colônias foi contado. Os resultados foram expressos em logaritmos de valores de unidades formadoras de colônias por ml (log UFC/mL) e analisados estatisticamente pelo teste ANOVA Kruskal-Wallis. Após 48 horas de incubação, o grupo OZE não apresentou crescimento de C. albicans. Os grupos CIV e controle apresentaram médias similares em todos os períodos testados. De acordo com os resultados obtidos, pode ser concluído que, sob as condições experimentais testadas, o cimento OZE apresentou-se mais efetivo in vitro sobre C. albicans em relação ao CIV.

The aim of this study was to evaluate the ability of endotoxin to diffuse through dentinal tubules towards the cement and to observe the period of time needed for it to reach the external root surface. Thirty single-rooted human teeth had their crowns and apices removed in order to standardize the root length to 15 mm. Teeth were instrumented until #30 K-file and made externally impermeable with epoxy adhesive, leaving 10 mm of the exposed root (middle third). The specimens were placed in plastic vials and irradiated (60Co gamma-rays). Then, they were divided into 2 groups (n = 15): G1) Escherichia coli endotoxin was inoculated into the root canal of the specimens and 1 ml of pyrogen-free water was put in the tubes; G2) (control): pyrogen-free water was inoculated into the root canals and 1 ml of pyrogen-free water was put in each tube. After 30 min, 2 h, 6 h, 12 h, 24 h, 48 h, 72 h and 7 days, the water of the tubes was removed and replaced. The removed aliquot was tested for the presence of endotoxin. Considering that the endotoxin is a B-lymphocyte polyclonal activator, at each experimental period, B-lymphocyte culture was stimulated with a sample of water removed from each tube and antibody (IgM) production was detected by ELISA technique. The results of IgM production were higher in groups of 24 h, 48 h, 72 h and 7 days in relation to the other studied groups, with statistically significant differences (ANOVA and Tukey's test p < 0.05). Endotoxin was able to diffuse through the dentinal tubules towards the cement, reaching the external root surface after the period of 24 h.O objetivo desta pesquisa foi avaliar in vitro a capacidade e o tempo necessário para a endotoxina se difundir pelos túbulos dentinários em direção ao cemento. Foram utilizados 30 dentes humanos unirradiculados, que tiveram suas coroas e seus ápices seccionados, padronizando-se o tamanho em 15 mm. Os dentes foram instrumentados até a lima K30 e impermeabilizados externamente com adesivo epóxi, deixando-se 10 mm de raiz exposta (terço médio). Os espécimes foram acondicionados em tubos plásticos e submetidos à radiação gama cobalto 60. Após a radiação, foram divididos em 2 grupos (n = 15): G1) foi inoculada uma solução de endotoxina de Escherichia coli no canal radicular dos espécimes e 1 mL de água apirogênica foi colocado no interior dos tubos; G2 (controle): foi inoculada água apirogênica nos canais radiculares e 1 mL de água apirogência foi colocado em cada tubo. Após 30 min, 2 h, 6 h, 12 h, 24 h, 48 h, 72 h e 7 dias, a água do interior dos tubos foi removida e substituída por outra. A alíquota removida foi testada para se detectar presença de endotoxina através da produção de anticorpos (IgM) em cultura de linfócitos B, pois a endotoxina é um ativador policlonal dessas células. Os resultados foram submetidos à análise estatística ANOVA (5%) e teste de Tukey, em que foi verificado que a água removida dos tubos após 24 h, 48 h, 72 h e 7 dias induziu maior produção de anticorpos em relação aos demais grupos, com diferença significante (p < 0,05). Assim, a endotoxina foi capaz de se difundir pelos túbulos dentinários em direção ao cemento, atingindo a região externa da raiz após 24 h.

Aim The present study evaluated the morphological and chemical changes of dentin produced by different sterilization methods, using scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry (EDS) analysis. Material and method Five human teeth were sectioned into 4 samples, each divided into 3 specimens. The specimens were separated into sterilization groups, as follows: wet heat under pressure; cobalt 60 gamma radiation; and control (without sterilization). After sterilization, the 60 specimens were analyzed by SEM under 3 magnifications: 1500X, 5000X, and 10000X. The images were analyzed by 3 calibrated examiners, who assigned scores according to the changes observed in the dentinal tubules: 0 = no morphological change; 1, 2 and 3 = slight, medium and complete obliteration of the dentinal tubules. The chemical composition of dentin was assessed by EDS, with 15 kV incidence and 1 μm penetration. Result The data obtained were submitted to the statistical tests of Kruskall-Wallis and ANOVA. It was observed that both sterilization methods – with autoclave and with cobalt 60 gamma radiation – produced no significant changes to the morphology of the dentinal tubules or to the chemical composition of dentin. Conclusion Both methods may thus be used to sterilize teeth for research conducted in vitro.

Background: This study aimed to compare the temperature increase produced by halogen bulb (HAL) and light-emitting diode (LED) light curing units (LCUs) by irradiating dentin discs (0.5 mm and 1 mm thickness), and to evaluate their cytotoxic effects on fibroblast culture in the presence of dentin discs due to the increasing demand on resin composite restorations and teeth bleaching for esthetic purposes. Methods: A total of 20 bovine incisors were used to obtain dentin discs and divided into four experimental groups (n=10): HAL0.5: irradiation with halogen-tungsten bulb Curing Light XL 3000 at an intensity of 470 mW/cm 2 over a dentin disc of 0.5 mm; LED0.5: irradiation with LED Optilight Max (GNATUS- Ribeirão Preto, SP, Brazil) at an intensity of 1200 mW/cm 2 over a dentin disc of 0.5 mm; HAL1: irradiation as in HAL0.5 but over a dentin disc of 1 mm; LED1: irradiation as in LED0.5 but over a dentin disc of 1 mm. The temperature increase was measured using a digital thermometer and the cytotoxicity was evaluated using an MTT assay with a mouse fibroblast cell line (L929). Parametric Data were analyzed by ANOVA and Tukey and non-parametric data were analyzed by Kruskal Wallis with Conover-Iman for non-parametric data (all with α=0.05). Results: A significant statistical difference was found between the groups HAL0.5 and HAL1 and both were different of LED0.5 and LED1 which presented higher temperature. All the experimental groups were different of the control group (without irradiation), and promoted reduction of cellular viability. Conclusions: HAL LCU promoted a lower temperature change in the dentin compared to LED, regardless of the dentin thickness (0.5-1 mm). Both HAL and LED LCUs decreased fibroblast viability; however, LED promoted more significant cytotoxic effects.