Microbiota present in combined endodontic-periodontal diseases and its risks for endocarditis.

INTRODUCTION: Infective endocarditis (IE) is an inflammatory disease usually caused by bacteria that enter the bloodstream and establish infections in the inner linings or valves of the heart, including blood vessels. Despite the availability of modern antimicrobial and surgical treatments, IE continues to cause substantial morbidity and mortality. Oral microbiota is considered one of the most significant risk factors for IE. The objective of this study was to evaluate the microbiota present in root canal (RC) and periodontal pocket (PP) clinical samples in cases with combined endo-periodontal lesions (EPL) to detect species related to IE using NGS. METHODS: Microbial samples were collected from 15 RCs and their associated PPs, also from 05 RCs with vital pulp tissues (negative control, NC). Genomic studies associated with bioinformatics, combined with structuring of a database (genetic sequences of bacteria reported for infective endocarditis), allowed for the assessment of the microbial community at both sites. Functional prediction was conducted using PICRUSt2. RESULTS: Parvimonas, Streptococcus, and Enterococcus were the major genera detected in the RCs and PPs. A total of 79, 96, and 11 species were identified in the RCs, PPs, and NCs, respectively. From them, a total of 34 species from RCs, 53 from PPs, and 2 from NCs were related to IE. Functional inference demonstrated that CR and PP microbiological profiles may not be the only risk factors for IE but may also be associated with systemic diseases, including myocarditis, human cytomegalovirus infection, bacterial invasion of epithelial cells, Huntington's disease, amyotrophic lateral sclerosis, and hypertrophic cardiomyopathy. Additionally, it was possible to predict antimicrobial resistance variants for broad-spectrum drugs, including ampicillin, tetracycline, and macrolides. CONCLUSION: Microorganisms present in the combined EPL may not be the only risk factor for IE but also for systemic diseases. Antimicrobial resistance variants for broad-spectrum drugs were inferred based on PICRUSt-2. State-of-the-art sequencing combined with bioinformatics has proven to be a powerful tool for conducting studies on microbial communities and could considerably assist in the diagnosis of serious infections. CLINICAL RELEVANCE: Few studies have investigated the microbiota in teeth compromised by combined endo-periodontal lesions (EPL), but none have correlated the microbiological findings to any systemic condition, particularly IE, using NGS techniques. In such cases, the presence of apical periodontitis and periodontal disease can increase IE risk in susceptible patients.

Chemomechanical preparation influences the microbial community and the levels of LPS, LTA and cytokines in combined endodontic-periodontal lesions: A clinical study.

BACKGROUND: This study was conducted to compare the microbiomes, the levels of lipopolysaccharides (LPS), lipoteichoic acid (LTA), and cytokines (interleukin [IL]-1ß and tumor necrosis factor-alpha [TNF-α]), before and after chemomechanical preparation (CMP) of the root canals (RC) and their associated periodontal pockets (PP) in teeth with combined EPL. MATERIALS: Samples were taken from 10 RC and PP, before and after CMP. The microbiomes (next-generation sequencing, V3-V4 hypervariable region of the 16S rRNA gene), microbiome diversity (bioinformatics analyses), LPS (limulus amebocyte lysate), LTA, IL-1ß, and TNF-α (ELISA) were evaluated. A statistical analysis was performed with significance level set at 5%. RESULTS: The most abundant phyla in both sites were Firmicutes and Proteobacteria. Comparative studies of bacterial genera species revealed that some increased and others decreased after CMP at both sites. A 3% reduction in Gram-negative bacteria (RC) and a 4% increase in Gram-positive bacteria (PP) were detected. LPS levels were 4.4 times higher in PP than in the RC. LTA was detected in all samples investigated. Higher levels of IL-1ß and TNF-α were detected in both sites at baseline. After CMP, LPS, LTA, IL-1ß and TNF-α were reduced in both sites. CONCLUSION: The microbial community in the RC and PP in teeth with combined EPL indicated a similarity between both sites. CMP effectively reduced the microbial load and the LPS levels from teeth with EPL, and consequently diminished the cytokine levels. The reduction in LTA levels in the RC and PP proved challenging.

Microbiomes of Endodontic-Periodontal Lesions before and after Chemomechanical Preparation.

INTRODUCTION: This study was conducted to evaluate the microbiomes of endodontic-periodontal lesions before and after chemomechanical preparation (CMP). METHODS: Clinical samples were taken from 15 root canals (RCs) with necrotic pulp tissues and from their associated periodontal pockets (PPs) (n = 15) of teeth with endodontic-periodontal lesions before and after CMP. The Human Oral Microbe Identification using Next Generation Sequencing (NGS) protocol and viable culture were used to analyze samples from RCs and PPs. The Mann-Whitney U test and Benjamini-Hochberg corrections were performed to correlate the clinical and radiographic findings with microbial findings (P < .05). RESULTS: Bacteria were detected in 100% of the samples in both sites (15/15) using NGS. Firmicutes was the most predominant phylum in both sites using both methods. The most frequently detected species in the RCs before and after CMP using NGS were Enterococcus faecalis, Parvimonas micra, Mogibacterium timidum, Filifactor alocis, and Fretibacterium fastidiosum. The species most frequently detected in the PPs before and after CMP using NGS were P. micra, E. faecalis, Streptococcus constellatus, Eubacterium brachy, Tannerella forsythia, and F. alocis. Associations were found between periapical lesions ≤ 2 mm and Desulfobulbus sp oral taxon 041 and with periodontal pockets ≥ 6 mm and Dialister invisius and Peptostreptococcus stomatis (all P < .05, found in the RCs before CMP). CONCLUSIONS: It is concluded that the microbial community present in combined endodontic-periodontal lesions is complex and more diverse than previously reported. It is important to note that bacteria do survive in some root canals after CMP. Finally, the similarity between the microbiota of both sites, before and after CMP, suggests there may be a pathway of infection between the pulp and periodontium.

Residual effects and surface alterations in disinfected gutta-percha and Resilon cones.

The aim of this study was to evaluate alterations on the surface of gutta-percha and Resilon cones when exposed to 2% chlorhexidine gel (CHX) and 5.25% sodium hypochlorite (NaOCl) and to evaluate their possible antibacterial residual effects against Enterococcus faecalis and Porphyromonas gingivalis. A total of 270 medium tapered cones (135 gutta-percha and 135 Resilon) were selected and divided into three groups, according to the substance (NaOCl, CHX, and sterile saline solution). The cones were immersed in each substance (for 1, 5, 10, 20, and 30 min), rinsed in saline solution, and dried. They were placed onto inoculated agar plates and incubated under specific conditions. Scanning electron microscopy analysis was performed on additional 270 disinfected cones. Another 18 cones were used as controls. Based on the results, it was concluded that Resilon cones exposed to CHX for 10, 20, and 30 min demonstrated residual antibacterial action and that substances did not cause alterations to the cones' surface.