What Is the Microbial Profile in Persistent Endodontic Infections? A Scoping Review.

INTRODUCTION: This scoping review aimed to map the evidence about the microbiota found in persistent endodontic infections. METHODS: The study protocol was prospectively registered and is available at https://osf.io/3g2cp. The electronic search was performed in MEDLINE via PubMed, Lilacs, BBO, Scopus, Web of Science, Cochrane Library, and Embase. The eligibility criteria were based on the PCC acronym, where P (Population) represents patients with teeth presenting persistent endodontic infection, C (Concept) represents microbial profile, and C (Context) represents undergoing endodontic retreatment. Clinical studies that evaluated the microbial profile of samples collected from root canals of teeth undergoing retreatment, using classical or molecular methods, were included. Studies that did not show a minimum period of 1 year between primary endodontic treatment and retreatment or did not radiographically evaluate the quality of primary root canal filling were excluded. Two reviewers independently selected the articles and collected data. RESULTS: From a total of 957 articles, 161 were read in full, and 32 studies were included. The most prevalent species were Enterococcus faecalis, Parvimonas micra, Porphyromonas endodontalis, Porphyromonas gingivalis, Prevotella intermedia, Dialister invisus, Propionibacterium acnes, Tannerella forsythia, and Treponema denticola. Cases with symptomatology or inadequate root canal filling presented an increase in specific bacterial species compared to those with no symptomatology or adequate filling. A greater number of microorganisms was observed in teeth with inadequate coronal restoration compared to those with adequate restoration. CONCLUSIONS: Persistent endodontic infections have a polymicrobial profile identified by the commonly used methods for bacterial detection/identification and are subject to the limitations present in each of those methods.

The effects of repeated applications of antimicrobial photodynamic therapy in the treatment of residual periodontal pockets: a systematic review.

The aim of this study was to assess the effects of repeated applications of antimicrobial photodynamic therapy (aPDT) on the non-surgical periodontal treatment of residual pockets. This work was performed and reported according to the Cochrane and PRISMA recommendations, respectively, and registered at the PROSPERO registry (number CRD42017058403). An extensive search of the biomedical literature was conducted on four databases from January 1960 to August 2018, followed by hand searching. Analysis of the quality of the selected studies was based on the risk of bias. Only two randomised controlled clinical trials (RCTs) met the inclusion criteria although they had unclear risk of bias. One study showed that repeated applications of aPDT in association with conventional non-surgical treatment during periodontal maintenance improved all clinical outcomes after 6 months. The other study, which assessed the effects of repeated applications of aPDT in association with ultrasound debridement on periodontal pathogens, showed no significant reduction of the main pathogens after 3-6 months but reported reductions of probing pocket depth and C-reactive protein after 3 and 6 months, respectively, compared to mechanical therapy alone. Concluding, it was not possible to state that repeated applications of aPDT, in association with non-surgical treatment of residual pockets, have effective clinical effects in the periodontal maintenance therapy. Although one can consider that aPDT is a promising adjuvant therapy, it is still necessary to carry out more RCTs with low risk of bias in order to confirm or refute the benefits of multiple applications for residual periodontal pockets.

Production and characterization of a biosurfactant produced by Streptomyces sp. DPUA 1559 isolated from lichens of the Amazon region

Surfactants are amphipathic compounds containing both hydrophilic and hydrophobic groups, capable to lower the surface or interfacial tension. Considering the advantages of the use of biosurfactants produced by microorganisms, the aim of this paper was to develop and characterize a biosurfactant produced by Streptomyces sp. DPUA1559 isolated from lichens of the Amazon region. The microorganism was cultured in a mineral medium containing 1% residual frying soybean oil as the carbon source. The kinetics of biosurfactant production was accompanied by reducing the surface tension of the culture medium from 60 to values around 27.14 mN/m, and by the emulsification index, which showed the efficiency of the biosurfactant as an emulsifier of hydrophobic compounds. The yield of the isolated biosurfactant was 1.74 g/L, in addition to the excellent capability of reducing the surface tension (25.34 mN/m), as observed from the central composite rotational design when the biosurfactant was produced at pH 8.5 at 28°C. The critical micelle concentration of the biosurfactant was determined as 0.01 g/mL. The biosurfactant showed thermal and pH stability regarding the surface tension reduction, and tolerance under high salt concentrations. The isolated biosurfactant showed no toxicity to the micro-crustacean Artemia salina, and to the seeds of lettuce (Lactuca sativa L.) and cabbage (Brassica oleracea L.). The biochemistry characterization of the biosurfactant showed a single protein band, an acid character and a molecular weight around 14.3 kDa, suggesting its glycoproteic nature. The results are promising for the industrial application of this new biosurfactant.

Production and characterization of a biosurfactant produced by Streptomyces sp. DPUA 1559 isolated from lichens of the Amazon region.

Surfactants are amphipathic compounds containing both hydrophilic and hydrophobic groups, capable to lower the surface or interfacial tension. Considering the advantages of the use of biosurfactants produced by microorganisms, the aim of this paper was to develop and characterize a biosurfactant produced by Streptomyces sp. DPUA1559 isolated from lichens of the Amazon region. The microorganism was cultured in a mineral medium containing 1% residual frying soybean oil as the carbon source. The kinetics of biosurfactant production was accompanied by reducing the surface tension of the culture medium from 60 to values around 27.14 mN/m, and by the emulsification index, which showed the efficiency of the biosurfactant as an emulsifier of hydrophobic compounds. The yield of the isolated biosurfactant was 1.74 g/L, in addition to the excellent capability of reducing the surface tension (25.34 mN/m), as observed from the central composite rotational design when the biosurfactant was produced at pH 8.5 at 28°C. The critical micelle concentration of the biosurfactant was determined as 0.01 g/mL. The biosurfactant showed thermal and pH stability regarding the surface tension reduction, and tolerance under high salt concentrations. The isolated biosurfactant showed no toxicity to the micro-crustacean Artemia salina, and to the seeds of lettuce (Lactuca sativa L.) and cabbage (Brassica oleracea L.). The biochemistry characterization of the biosurfactant showed a single protein band, an acid character and a molecular weight around 14.3 kDa, suggesting its glycoproteic nature. The results are promising for the industrial application of this new biosurfactant.

Effects of low and standard fluoride toothpastes on caries and fluorosis: systematic review and meta-analysis.

Although the anti-caries effects of standard fluoride (F) toothpastes are well established, their use by preschoolers (2- to 5-year-olds) has given rise to concerns regarding the development of dental fluorosis. Thus, a widespread support of low F toothpastes has been observed. The aim of this study was to assess the effects of low (<600 ppm) and standard (1,000-1,500 ppm) F toothpastes on the prevention of caries in the primary dentition and aesthetically objectionable (moderate to severe) fluorosis in the permanent dentition. A systematic review of clinical trials and meta-analyses were carried out. Two examiners independently screened 1,932 records and read 159 potentially eligible full-text articles. Data regarding characteristics of participants, interventions, outcomes, length of follow-up and potential of bias were independently extracted by two examiners and disagreements were solved by consensus after consulting a third examiner. In order to assess the effects of low and standard F toothpastes on the proportion of children developing caries and fluorosis, pooled relative risks (RR) and associated 95% confidence intervals were estimated using a fixed and a random-effects model, respectively. Five clinical trials fulfilled the inclusion criteria. Low F toothpastes significantly increased the risk of caries in primary teeth [RR = 1.13 (1.07-1.20); 4,634 participants in three studies] and did not significantly decrease the risk of aesthetically objectionable fluorosis in the upper anterior permanent teeth [RR = 0.32 (0.03-2.97); 1,968 participants in two studies]. There is no evidence to support the use of low F toothpastes by preschoolers regarding caries and fluorosis prevention.

Toxicological analysis and effectiveness of oral Kalanchoe pinnata on a human case of cutaneous leishmaniasis.

Leishmaniasis is an extremely difficult disease to treat. Previously, it was shown that oral Kalanchoe pinnata (Kp) leaf extract is strongly effective against murine leishmaniasis. Here, it is shown that the serum levels of alanine-aminotransferase (ALT), aspartate-aminotransferase (AST), urea and alkaline phosphatase were unchanged in mice orally treated with supraoptimal Kp doses for 30 days, indicating the absence of chronic toxicity to the liver, heart or kidney. Additionally, evidence is presented that human leishmaniasis may also be controlled with oral Kp. A 36-year-old man with an active cutaneous leishmaniasis was orally treated with 30 g wet weight of Kp leaves/day for 14 days. During the Kp treatment, the lesion stopped growing and slightly decreased. No adverse reactions or toxicity was observed. This study reports for the first time that Kalanchoe pinnata contains substances potentially active and safe for the oral treatment of human cutaneous leishmaniasis.