Preclinical in vitro study of streptococcus mutans accumulation in three fixed retainer designs: Microbiological assay.

The use of fixed retainers in the lower arch is frequent; however, its presence increases the accumulation of biofilm and dental calculus. The objective of this research was to evaluate, in vitro, the accumulation of Streptococcus mutans (S. mutans) in 3 designs of fixed retainers. Nine models were reproduced in heat-cured acrylic resin and divided into groups: straight retainer (SR), retainer with vertical strap (RVS), retainer with horizontal strap (RHS). The accumulation of S. mutans was assessed using the MTT assay (3-4,5-dimethyl-thiazol-2-yl-2,5-diphenyltetrazolium bromide) and then measured using an automated reader. The RHS group showed less biofilm accumulation compared to the other groups (p<0.05). The distance between the tooth surface and the retainer showed a strong negative correlation with biofilm accumulation (rs=-0.79, p=0.00037). The RHS showed significantly less accumulation of S. mutans due to the distance between the retainer and the tooth surface. This research provides relevant data for a future randomized clinical trial.

Can hyperglycemia be associated with caries activity and root caries in adults?

AIMS: A previous meta-analysis showed that individuals with Type 2 diabetes mellitus (T2D) have a greater chance of developing both coronal caries and root caries than systemically healthy ones, which can be influenced by hyperglycemia per se. This study aimed to associate blood and salivary glucose levels with caries. METHODS: This research is a subset of a cross-sectional study. N = 39 individuals underwent a dental examination and salivary glucose, fasting blood glucose (FBG) and glycated hemoglobin (A1c) measurements. RESULTS: The prevalence of active coronal caries was 10.2%, and that of root caries was 20.5%. A1c and FBG averages were higher in individuals with root caries (9.75 ± 1.71 and 186.3 ± 62.5) than without (7.01 ± 2.23 and 115.1 ± 48.6; p < 0.05). Individuals with T2D showed weak correlation of salivary glucose and number of active coronal caries. Significant correlations were observed between salivary and blood glucose. There was relevance of A1c (0.53; CI=0.124-0.941; p = 0.01) and FBG (0.019; CI=0.006-0.033; p = 0.006) toward the increased number of root caries lesions, even after adjustment for salivary flow and age. CONCLUSION: Blood glucose levels are associated with an increased number of root caries in adults with or without T2D. In individuals with T2D, salivary glucose was correlated with active coronal caries. Additional studies are needed to support this association.

Does the use of natural products for endodontic therapy in primary teeth have sufficient evidence for clinical practice? A scoping review.

OBJECTIVES: The use of natural products for pulp therapy has experienced a remarkable advancement in recent years. The aim was to provide a critical appraisal of the safety and efficacy of natural products for endodontic therapy in primary teeth and verify whether their uses in clinical practice have sufficient evidence. MATERIALS AND METHODS: Two reviewers searched ten databases (Cochrane, DOSS, Embase, Google Scholar, LILACS, OpenGrey, Proquest, PubMed, Scopus, and Web of Science) until January 2022, identifying references that evaluated the safety and efficacy of the use of natural products for endodontic therapy in primary teeth. Cohort, randomized, and non-randomized clinical trials were included. RESULTS: A total of 3583 references were initially identified. From the 63 studies retrieved for full-text reading, 37 fulfilled the selection criteria and were included in the qualitative analysis. The studies investigated 19 natural products for pulpotomy medicament, irrigating solution, intracanal medication, and root canal filling material. Most studies showed similar efficacy of natural products and their control groups; however, many methodological biases and concerns about the safety and efficacy of natural products were identified, questioning their clinical applicability. CONCLUSIONS: The included studies provided insufficient evidence to support safe and effective clinical application of natural products for endodontic therapy in primary teeth. Future well-designed studies with representative samples are needed to support the use of natural products for endodontic therapy in primary teeth. CLINICAL RELEVANCE: The use of natural products for endodontic therapy in primary teeth requires caution by clinicians, due to the insufficient available evidence.

Expression of inflammatory mediators in periodontitis and T2D patients: a systematic review and meta-analysis.

The high concentration of glucose in the blood in Type 2 diabetes (T2D) may be related to either insulin resistance or insulin deficiency. Moreover, the literature points to periodontitis as the main oral disease caused by glycemia imbalance. The quantification of inflammatory markers in blood or saliva samples of T2D patients may represent a valuable tool in revealing how well an individual's immune system can respond to injuries and periodontal treatment. In addition, an evaluation of the cytokine expression is extremely relevant to help understand the connection between periodontitis and T2D. This systematic review and meta-analysis aimed to evaluate the expression of inflammatory markers in T2D patients with periodontitis, compared with non-diabetic patients with periodontitis. A total of 3,894 studies were retrieved after a systematic literature search, 15 of which were included in the systematic review, and 4 of these 15, in the meta-analysis. The results did not indicate any statistical difference between the groups regarding TNF-α and IL-6 markers. T2D patients with periodontitis had increased levels of IL-10, compared with non-diabetic individuals with periodontitis (p = 0.003). On the other hand, the IL-4 concentration in non-diabetic individuals with periodontitis was high, compared with the T2D group (p< 0.001). Several studies did not include quantitative results and were excluded from the meta-analysis. The high IL-10 expression and low IL-4 expression in the T2D group suggest an association between the level of these markers and the impairment of the immune response in T2D patients with periodontitis.

Enrichment of sulphate-reducers and depletion of butyrate-producers may be hyperglycaemia signatures in the diabetic oral microbiome.

Objectives: This study aimed to investigate oral microbial signatures associated with hyperglycaemia, by correlating the oral microbiome with three glycaemic markers. Potential association between clinical parameters and oral bacterial taxa that could be modulating the hyperglycaemic microbiome was also explored. Methods: Twenty-three individuals diagnosed with type 2 Diabetes Mellitus (T2D) and presenting periodontitis were included, as well as 25 systemically and periodontally healthy ones. Fasting blood glucose, glycated haemoglobin, salivary glucose, periodontitis classification, caries experience and activity and salivary pH were evaluated. The V4 region of the 16S rRNA gene was amplified from total salivary DNA, and amplicons were sequenced (Illumina MiSeq). Results: Hyperglycaemia was correlated with proportions of Treponema, Desulfobulbus, Phocaiecola and Saccharimonadaceae. Desulfobulbus was ubiquitous and the most enriched organism in T2D individuals (log2FC = 4). The Firmicutes/Bacteroidetes ratio was higher at alkali salivary pH than acidic pH. In the network analysis, Desulfobulbus was clustered in a negative association with caries-associated and butyrate-producing bacteria. Conclusion: The salivary microbiome is shaped by systemic hyperglycaemia, as well as changes in the salivary pH, which may be linked to local hyperglycaemia. The enrichment of predictive biomarkers of gut dysbiosis in the salivary microbiome can reflect its capacity for impairment of hyperglycaemia.

Guided endodontic treatment in a region of limited mouth opening: a case report of mandibular molar mesial root canals with dystrophic calcification.

BACKGROUND: The endodontic treatment of calcified root canals in molars is a challenging and time-consuming procedure. Even with the aid of a surgical microscope, the risk of root perforation is high, especially in the furcation area. The purpose of this study is to report the Computer-Aided-Design and Manufacturing (CAD-CAM) workflow, the innovative strategies for the template ideation, and the guided endodontic treatment of a mandibular molar with dystrophic calcification in the mesial root canals. CASE PRESENTATION: A 58-year-old female patient, ASA I, was referred to endodontic treatment in the right first mandibular molar for prosthetic reasons. The mesiobuccal and mesiolingual canals appeared obliterated in the radiographic images. The absence of dental crown, tooth inclination, and the limited mouth opening of the region contributed to a poor visual reference of the tooth in the dental arch and the direction of the remaining lumens of the canals. Despite using surgical microscopy, the conventional technique led to the deviation of the mesiobuccal canal towards the furcation area. The obliteration of both mesial root canals was confirmed using the Cone Beam Computer Tomography. The clinical history associated with the tomography diagnosis was compatible with dystrophic calcifications in the pulp canals. The patient was submitted to an intra-oral scanning as well. The Digital Imaging and Communications in Medicine data (DICOM) were segmented. The Standard Tessellation Language (STL) files were processed following the CAD-CAM workflow, aiming to create two different endodontic templates with a new open design concept. The templates with open design allowed direct visualization of the operative field, irrigation, and dentin debris removal. The strategy of the guidance sleeves niche as half-cylinders allowed the drill insertion in a limited mouth opening region. CONCLUSIONS: The digital planning and guided access permitted to overcome the case limitations and then re-establish the glide path following the original anatomy of the root canals. The guided endodontic represents a personalized technique that provides security, reduced risks of root perforation, and a significant decrease of the working time to access obliterated root canals even in the mesial root canal of mandibular molars, a region of limited mouth opening.

The Complex Interrelationship between Diabetes Mellitus, Oral Diseases and General Health.

There is emerging evidence that several oral diseases and conditions can be associated with DM. Dental caries, hyposalivation, fungal diseases and endodontics lesions may represent potential oral complications that can be aggravated by chronic hyperglycemia. Individuals with DM have a low perception of oral diseases which can lead to clinically important oral and systemic complications. This review aims to provide data on the most common oral signs and symptoms related to DM and to explore the mechanisms that might explain associations between DM and oral diseases in order to clarify the risks posed by poor oral health in DM. Since the linkage between oral diseases and DM is part of multifactorial aspects related to chronic hyperglycemic status and several common conditions affecting the whole body, both require rigorous self-control from patients and attention from medical and dental professionals.

Expression of inflammatory mediators in periodontitis and T2D patients: a systematic review and meta-analysis

Abstract The high concentration of glucose in the blood in Type 2 diabetes (T2D) may be related to either insulin resistance or insulin deficiency. Moreover, the literature points to periodontitis as the main oral disease caused by glycemia imbalance. The quantification of inflammatory markers in blood or saliva samples of T2D patients may represent a valuable tool in revealing how well an individual's immune system can respond to injuries and periodontal treatment. In addition, an evaluation of the cytokine expression is extremely relevant to help understand the connection between periodontitis and T2D. This systematic review and meta-analysis aimed to evaluate the expression of inflammatory markers in T2D patients with periodontitis, compared with non-diabetic patients with periodontitis. A total of 3,894 studies were retrieved after a systematic literature search, 15 of which were included in the systematic review, and 4 of these 15, in the meta-analysis. The results did not indicate any statistical difference between the groups regarding TNF-α and IL-6 markers. T2D patients with periodontitis had increased levels of IL-10, compared with non-diabetic individuals with periodontitis (p = 0.003). On the other hand, the IL-4 concentration in non-diabetic individuals with periodontitis was high, compared with the T2D group (p< 0.001). Several studies did not include quantitative results and were excluded from the meta-analysis. The high IL-10 expression and low IL-4 expression in the T2D group suggest an association between the level of these markers and the impairment of the immune response in T2D patients with periodontitis.

Clinical parameters of individuals with periodontitis and Diabetes Mellitus reveals signatures of the minority microbiota in saliva / Los parámetros clínicos de las personas con periodontitis y diabetes mellitus revelan firmas de la microbiota minoritaria en la saliva / Parâmetros clínicos de indivíduos com periodontite e diabetes mellitus revelam assinaturas da microbiota minoritária na saliva

Aims: This pilot study aimed to describe the majority and minority microbiota of saliva from individuals with advanced periodontitis, with or without type 2 diabetes mellitus (T2D), correlating the relative abundance of microorganisms with clinical parameters. Material/Methods: Six individuals diagnosed with periodontitis were included and classified according to their diagnosis of T2D. Salivary pH, number of teeth with active caries lesions, number of remaining teeth, periodontal and glycemic parameters were evaluated. V4 region amplicons of the 16S rRNA from salivary DNA were sequenced at Ion PGM. Amplicon sequence variants (ASVs) were compared according to the clinical parameters. Results: Correlation showed eight low-abundant bacteria significantly correlated with co-variables, either positively or negatively. The periodontitis-associated bacteria followed the increasing pH and number of remaining teeth. Conclusions: This survey provided potential minority microbiota correlations with clinical parameters, such as number of remaining teeth, FBG, and salivary pH. The ubiquity of some low abundant microorganisms in individuals with advanced periodontitis, exposed or not to type 2 DM, can reveal microbial signatures not yet explored.

Oral Phenotype and Salivary Microbiome of Individuals With Papillon-Lefèvre Syndrome.

Papillon-Lefèvre syndrome (PLS) is an autosomal recessive rare disease, main characteristics of which include palmoplantar hyperkeratosis and premature edentulism due to advanced periodontitis (formerly aggressive periodontitis). This study aimed to characterize the oral phenotype, including salivary parameters, and the salivary microbiome of three PLS sisters, comparatively. Two sisters were toothless (PLSTL1 and PLSTL2), and one sister had most of the teeth in the oral cavity (PLST). Total DNA was extracted from the unstimulated saliva, and the amplicon sequencing of the 16S rRNA gene fragment was performed in an Ion PGM platform. The amplicon sequence variants (ASVs) were obtained using the DADA2 pipeline, and the taxonomy was assigned using the SILVA v.138. The main phenotypic characteristics of PLS were bone loss and premature loss of primary and permanent dentition. The PLST sister presented advanced periodontitis with gingival bleeding and suppuration, corresponding to the advanced periodontitis as a manifestation of systemic disease, stage IV, grade C. All three PLS sisters presented hyposalivation as a possible secondary outcome of the syndrome. Interestingly, PLST salivary microbiota was dominated by the uncultured bacteria Bacterioidales (F0058), Fusobacterium, Treponema, and Sulfophobococcus (Archaea domain). Streptococcus, Haemophilus, and Caldivirga (Archaea) dominated the microbiome of the PLSTL1 sister, while the PLSTL2 had higher abundances of Lactobacillus and Porphyromonas. This study was the first to show a high abundance of organisms belonging to the Archaea domain comprising a core microbiome in human saliva. In conclusion, a PLST individual does have a microbiota different from that of the periodontitis' aggressiveness previously recognized. Due to an ineffective cathepsin C, the impairment of neutrophils probably provided a favorable environment for the PLS microbiome. The interactions of Bacteroidales F0058, Caldivirga, and Sulfophobococcus with the microbial consortium of PLS deserves future investigation. Traditional periodontal therapy is not efficient in PLS patients. Unraveling the PLS microbiome is essential in searching for appropriate treatment and avoiding early tooth loss.

Calcium silicate-based cements cause environmental stiffness and show diverse potential to induce osteogenesis in human osteoblastic cells.

Calcium silicate-based cements differ markedly in their radiopacifiers and the presence of calcium sulfate, aluminates, carbonates and other components that can affect their biological properties. This study aimed to compare the biological properties of six calcium silicate cements in human osteoblastic cell culture (Saos-2 cells): Bio-C Repair (Bio-C), PBS HP (PBS-HP), Biodentine (Biodentine), MTA Repair HP (MTA-HP), NeoMTA Plus (NeoMTA-P), and ProRoot MTA (ProRoot). After exposure to these materials, the cells were analyzed by MTT, wound healing, cell migration, and alkaline phosphatase activity (ALP) assays, real-time PCR (qPCR) analysis of the osteogenesis markers (osteocalcin or bone gamma-carboxyglutamate protein, BGLAP; alkaline phosphatase, ALPL; bone sialoprotein or secreted phosphoprotein 1, BNSP), and alizarin red staining (ARS). Curiously, the migration rates were low 24-48 h after exposure to the materials, despite the cells showing ideal rates of viability. The advanced and intermediate cell differentiation markers BGLAP and BNSP were overexpressed in the Bio-C, MTA-HP, and ProRoot groups. Only the Biodentine group showed ALPL overexpression, a marker of initial differentiation. However, the enzymatic activity was high in all groups except Biodentine. The mineralization area was significantly large in the NeoMTA-P, ProRoot, PBS-HP, MTA-HP, and Bio-C groups. The results showed that cellular environmental stiffness, which impairs cell mobility and diverse patterns of osteogenesis marker expression, is a consequence of cement exposure. Environmental stiffness indicates chemical and physical stimuli in the microenvironment; for instance, the release of cement compounds contributes to calcium phosphate matrix formation with diverse stiffnesses, which could be essential or detrimental for the migration and differentiation of osteoblastic cells. Cells exposed to Bio-C, PBS-HP, ProRoot, NeoMTA-P, and MTA-HP seemed to enter the advanced or intermediate differentiation phases early, which is indicative of the diverse potential of cements to induce osteogenesis. Cements that quickly stimulate osteoblast differentiation may be ideal for reparative and regenerative purposes since they promptly lead to dentin or bone deposition.

Cimento biocerâmico no tratamento conservador de perfuração radicular em molar inferior / Bioceramic sealer in conservative treatment of mandibular molar root perforation

Introdução: A perfuração radicular é um acidente técnico-operatório que resulta em comunicação da cavidade pulpar com os tecidos periodontais. Esse tipo de acidente pode apresentar prognóstico desfavorável, por afetar significativamente o soalho da câmara coronária ou os terços cervical, médio e apical do canal radicular. Entre os fatores que interferem no prognóstico das perfurações radiculares, destacam-se: localização, extensão, presença ou ausência de bolsa periodontal; tempo decorrido entre a perfuração e o tratamento; e tipo de material obturador. Nesse contexto, os cimentos obturadores de canais denominados biocerâmicos surgiram como uma proposta inovadora para tratamento de perfurações antes consideradas de prognóstico desfavorável. Objetivo: O presente trabalho teve por objetivo relatar o tratamento de uma perfuração radicular em molar inferior com o cimento biocerâmico EndoSequence BC Sealer, com três anos de acompanhamento. Resultados: As imagens radiográficas e os dados clínicos do paciente evidenciaram o sucesso no tratamento da perfuração, com reparo da lesão perirradicular. Conclusão: O cimento endodôntico biocerâmico EndoSequence BC Sealer associado com a retomada do trajeto original do conduto e sua instrumentação favoreceram o reparo dos tecidos perirradiculares, sugerindo propriedades biológicas promissoras de compatibilidade e bioativida (AU).

Introduction: Root perforation is a technical-surgical accident that results in communication of the pulp cavity with periodontal tissues. This type of accident may have an unfavorable prognosis because it significantly affects the floor of the coronary chamber or the cervical, middle and apical thirds of the root canal. Factors that interfere with the prognosis of root perforations include location, extension, presence or absence of periodontal pocket, time elapsed between perforation and treatment, and type of obturator material. In this context, bioceramic canal sealers have emerged as an innovative proposal for treatment of perforations previously considered to have an unfavorable prognosis. Objective: The aim of this study was to report the treatment of a lower molar root perforation with the EndoSequence BC Sealer bioceramic sealer after a 3-year follow up. Results: Radiographic images and patient clinical data showed success in the treatment of perforation with repair of the periradicular lesion. Conclusion: Endo-Sequence BC Sealer bioceramic endodontic sealer associated with the resumption of the original conduit path and its instrumentation favored the repair of periradicular tissues, suggesting promising biological properties of compatibility and bioactivity (AU).

The Impact of Rehabilitation-oriented Virtual Reality Device in Patients With Ischemic Stroke in the Early Subacute Recovery Phase: Study Protocol for a Phase III, Single-Blinded, Randomized, Controlled Clinical Trial.

BACKGROUND AND RATIONALE: Stroke is considered the most common cause of adult disability. Intensive rehabilitation protocols outperform nonintensive counterparts. The subacute stroke phase represents a potential window to recovery. Virtual reality (VR) has been shown to provide a more stimulating environment, allowing for increased patient compliance. However, the quality of current literature comparing VR with standard therapies is limited. Our aim is to measure the impact of VR versus standard therapy on the recovery of the upper limb motor function in patients with stroke in the early subacute recovery phase. METHOD: This is a randomized, controlled trial that will assign 262 patients to tailor-made standard rehabilitation (TMSR) or TMSR plus immersive VR device. The trial will be conducted in an urban rehabilitation clinic in the United States with expertise in the management of poststroke patients. Patients will be 18 to 70 years of age and in the early subacute period (30-90 days post ischemic stroke). The primary outcome will be the change of Fugl-Meyer Assessment-Upper Extremity (FMA-UE) score, measured at baseline and 13 weeks after randomization. The secondary outcome will be the change in the UK Functional Independence Measure and Functional Assessment Measure (UK FIM-FAM) score at the same time points. DISCUSSION: If the use of VR in the rehabilitation of patients with stroke proves to have a significant impact on their motor recovery, it will constitute an extremely important step into decreasing the functional impairment associated with stroke and the related health care expense burden.

Effects of PI3K and FSH on steroidogenesis, viability and embryo development of the cumulus-oocyte complex after in vitro culture.

The purpose of this study was to evaluate the effects of FSH and PI3K on the nuclear maturation, viability, steroidogenesis and embryo development of bovine cumulus-oocyte complexes (COCs). Oocyte maturation was achieved with MIV B, MIV B+100 µM LY294002, MIV B+10 ng/mL follicle stimulating hormone (FSH), or MIV B+10 ng/mL FSH+100 µM LY294002 treatments for 22-24 h. After the cultured COCs were denuded, oocytes were separated into those that extruded polar bodies (mature) and those that did not, and real-time polymerase chain reaction (PCR) for BAX, BCL2, LHR, FSHR, CYP11A1, CYP19A1 and HSD17B1 genes was performed. The culture medium was collected to determine the levels of 17ß-estradiol (E2) and progesterone (P4). The trypan blue test was used to study COC viability, and embryo development was evaluated. FSH increased nuclear maturation and PI3K blocked the maturation but did not influence oocyte viability. BAX and BCL2 expression levels in the cumulus cells were only affected by FSH, and the BAX levels decreased after treatment with LY294002. FSH increased the levels of E2 and P4, however inhibition of PI3K decreased E2 levels. MIV B enhanced levels of LHR, FSHR, CYP11A1, CYP19A1 and HSD17B1, whereas LY294002 inhibited the expression levels of all genes. MIV B+FSH decreased the expression levels of all genes except CYP11A1. LY294002 did not demonstrate any effects in the presence of FSH. Embryo development was significantly decreased when the MIV B+FSH medium was used. In conclusion, FSH controls the steroidogenesis, viability and gene expression in COCs. PI3K plays essential roles in nuclear maturation, steroidogenesis and embryo development.

Biocompatibility and bioactivity of calcium silicate-based endodontic sealers in human dental pulp cells.

UNLABELLED: Mineral Trioxide Aggregate (MTA) is a calcium silicate-based material. New sealers have been developed based on calcium silicate as MTA Fillapex and MTA Plus. OBJECTIVE: The aim of this study was to evaluate biocompatibility and bioactivity of these two calcium silicate-based sealers in culture of human dental pulp cells (hDPCs). MATERIAL AND METHODS: The cells were isolated from third molars extracted from a 16-year-old patient. Pulp tissue was sectioned into fragments with approximately 1 mm3 and kept in supplemented medium to obtain hDPCs adherent cultures. Cell characterization assays were performed to prove the osteogenic potential. The evaluated materials were: MTA Plus (MTAP); MTA Fillapex (MTAF) and FillCanal (FC). Biocompatibility was evaluated with MTT and Neutral Red (NR) assays, after hDPCs exposure for 24 h to different dilutions of each sealer extract (1:2, 1:3 and 1:4). Unexposed cells were the positive control (CT). Bioactivity was assessed by alkaline phosphatase (ALP) enzymatic assay in cells exposed for one and three days to sealer extracts (1:4 dilution). All data were analyzed by ANOVA and Tukey post-test (p≤0.05%). RESULTS: MTT and NR results showed suitable cell viability rates for MTAP at all dilutions (90-135%). Cells exposed to MTAF and FC (1:2 and 1:4 dilutions) showed significant low viability rate when compared to CT in MTT. The NR results demonstrated cell viability for all materials tested. In MTAP group, the cells ALP activity was similar to CT in one and three days of exposure to the material. MTAF and FC groups demonstrated a decrease in ALP activity when compared to CT at both periods of cell exposure. CONCLUSIONS: The hDPCs were suitable for the evaluation of new endodontic materialsin vitro. MTAP may be considered a promising material for endodontic treatments.

Biocompatibility and bioactivity of calcium silicate-based endodontic sealers in human dental pulp cells

Mineral Trioxide Aggregate (MTA) is a calcium silicate-based material. New sealers have been developed based on calcium silicate as MTA Fillapex and MTA Plus.Objective The aim of this study was to evaluate biocompatibility and bioactivity of these two calcium silicate-based sealers in culture of human dental pulp cells (hDPCs).Material and Methods The cells were isolated from third molars extracted from a 16-year-old patient. Pulp tissue was sectioned into fragments with approximately 1 mm3 and kept in supplemented medium to obtain hDPCs adherent cultures. Cell characterization assays were performed to prove the osteogenic potential. The evaluated materials were: MTA Plus (MTAP); MTA Fillapex (MTAF) and FillCanal (FC). Biocompatibility was evaluated with MTT and Neutral Red (NR) assays, after hDPCs exposure for 24 h to different dilutions of each sealer extract (1:2, 1:3 and 1:4). Unexposed cells were the positive control (CT). Bioactivity was assessed by alkaline phosphatase (ALP) enzymatic assay in cells exposed for one and three days to sealer extracts (1:4 dilution). All data were analyzed by ANOVA and Tukey post-test (p≤0.05%).Results MTT and NR results showed suitable cell viability rates for MTAP at all dilutions (90-135%). Cells exposed to MTAF and FC (1:2 and 1:4 dilutions) showed significant low viability rate when compared to CT in MTT. The NR results demonstrated cell viability for all materials tested. In MTAP group, the cells ALP activity was similar to CT in one and three days of exposure to the material. MTAF and FC groups demonstrated a decrease in ALP activity when compared to CT at both periods of cell exposure.Conclusions The hDPCs were suitable for the evaluation of new endodontic materialsin vitro. MTAP may be considered a promising material for endodontic treatments.

Radiopacity and cytotoxicity of Portland cement associated with niobium oxide micro and nanoparticles

Objective Mineral Trioxide Aggregate (MTA) is composed of Portland Cement (PC) and bismuth oxide (BO). Replacing BO for niobium oxide (NbO) microparticles (Nbµ) or nanoparticles (Nbη) may improve radiopacity and bioactivity. The aim of this study was to evaluate the radiopacity and cytotoxicity of the materials: 1) PC; 2) White MTA; 3) PC+30% Nbµ; 4) PC+30% Nbη. Material and Methods For the radiopacity test, specimens of the different materials were radiographed along an aluminum step-wedge. For cell culture assays, Saos-2 osteoblastic-cells (ATCC HTB-85) were used. Cell viability was evaluated through MTT assay, and bioactivity was assessed by alkaline phosphatase activity assay. Results The results demonstrated higher radiopacity for MTA, followed by Nbµ and Nbη, which had similar values. Cell culture analysis showed that PC and PC+NbO associations promoted greater cell viability than MTA. Conclusions It was concluded that the combination of PC+NbO is a potential alternative for composition of MTA. .

Radiopacity and cytotoxicity of Portland cement associated with niobium oxide micro and nanoparticles.

OBJECTIVE: Mineral Trioxide Aggregate (MTA) is composed of Portland Cement (PC) and bismuth oxide (BO). Replacing BO for niobium oxide (NbO) microparticles (Nbµ) or nanoparticles (Nbη) may improve radiopacity and bioactivity. The aim of this study was to evaluate the radiopacity and cytotoxicity of the materials: (1) PC; (2) White MTA; (3) PC+30% Nbµ; (4) PC+30% Nbη. MATERIAL AND METHODS: For the radiopacity test, specimens of the different materials were radiographed along an aluminum step-wedge. For cell culture assays, Saos-2 osteoblastic-cells (ATCC HTB-85) were used. Cell viability was evaluated through MTT assay, and bioactivity was assessed by alkaline phosphatase activity assay. RESULTS: The results demonstrated higher radiopacity for MTA, followed by Nbµ and Nbη, which had similar values. Cell culture analysis showed that PC and PC+NbO associations promoted greater cell viability than MTA. CONCLUSIONS: It was concluded that the combination of PC+NbO is a potential alternative for composition of MTA.

B-cell maturation antigen, a proliferation-inducing ligand, and B-cell activating factor are candidate mediators of spinal cord injury-induced autoimmunity.

Autoimmunity is thought to contribute to poor neurological outcomes after spinal cord injury (SCI). There are few mechanism-based therapies, however, designed to reduce tissue damage and neurotoxicity after SCI because the molecular and cellular bases for SCI-induced autoimmunity are not completely understood. Recent groundbreaking studies in rodents indicate that B cells are responsible for SCI-induced autoimmunity. This novel paradigm, if confirmed in humans, could aid in the design of neuroprotective immunotherapies. The aim of this study was to investigate the molecular signaling pathways and mechanisms by which autoimmunity is induced after SCI, with the goal of identifying potential targets in therapies designed to reduce tissue damage and inflammation in the chronic phase of SCI. To that end, we performed an exploratory microarray analysis of peripheral blood mononuclear cells to identify differentially expressed genes in chronic SCI. We identified a gene network associated with lymphoid tissue structure and development that was composed of 29 distinct molecules and five protein complexes, including two cytokines, a proliferation-inducing ligand (APRIL) and B-cell-activating factor (BAFF), and one receptor, B-cell maturation antigen (BMCA) involved in B cell development, proliferation, activation, and survival. Real-time polymerase chain reaction analysis from ribonucleic acid samples confirmed upregulation of these three genes in SCI. To our knowledge, this is the first report that peripheral blood mononuclear cells produce increased levels of BAFF and APRIL in chronic SCI. This finding provides evidence of systemic regulation of SCI-autoimmunity via APRIL and BAFF mediated activation of B cells through BMCA and points toward these molecules as potential targets of therapies designed to reduce neuroinflammation after SCI.

Incomplete vertical root fracture associated with lateral compactiontechnique: a microscopic analysis / Fratura radicular vertical incompleta associada com a técnica de condensação lateral: Análise microscópica

Objective: This study evaluated the effects of root canal obturation employing lateral compaction technique and spreader load of 1.5 kg on the incidence of complete (CVRF) or incomplete vertical root fractures (IVRF). Material and Methods: Twenty-seven distal roots of extracted human mandibular molars were used. All root canals were prepared by biomechanical step-back technique and obturated by lateral compaction technique. The prepared roots were distributed into two groups: G1- experimental (n = 17)= and G2- control (n = 10). During obturation, load of 1.5 kg was applied to a size # 30 finger spreader. Pre- and post-obturation images of the coronal portion of the roots were captured by inverted digital microscopy and analyzed by one trained examiner. Data were evaluated by Fisher’s test (p < 0.05) using GrapH Pad Prism 5.0. Results: No roots exhibited CVRF. All fractures observed before and after obturation were IVRF or “other defects”. In G2 (control group), there was no increase of IVRF number. Interestingly, G1 presented an increase in the IVRF number to 70.59% in the 12 teeth out of 17 teeth studied. The statistical analysis showed that the mean of IVRF increased significantly in G1 when compared to G2 (p < 0.05). Conclusion: The application of a 1.5 kg spreader load during lateral compaction technique does not produce complete vertical root fractures, but may produce incomplete fractures or “other defects”.

Objetivo: Este estudo avaliou os efeitos da obturação dos canais radiculares, empregando a técnica de condensação lateral com uma força do espaçador de 1,5 kg, na incidência de fraturas radiculares verticais completas (FRVC) ou incompletas (FRVI). Material e Métodos: Foram usadas 27 raízes distais de dentes molares mandibulares humanosextraídos. Todas as raízes foram instrumentadas por meio da técnica clássica ápice-coroa e obturadas pela técnica de condensação lateral. Após o preparo biomecânico, as raízes foram distribuídas em 2 grupos: G1- experimental (n = 17) e G2- controle (n = 10). Durante a obturação, uma força de 1,5 kg foi aplicada ao espaçador digital # 30. As imagens pré- e pós-obturação da superfície coronal das raízes foram capturadas por meio de um microscópio digital invertido e analisadas por um examinador treinado. Os dados obtidos foram avaliados por meio do teste de Fisher (p < 0,05) usando o programa GrapH Pad Prism 5.0. Resultados: Não foram detectadas FRVC. Todas as fraturas observadas antes e após a obturação foram FRVI ou “outros defeitos”. No G2 (grupo controle), não houve um aumento no número de FRVI. Curiosamente, G1 apresentou um aumento das FRVI em 70,59% (12/17 raízes). A análise estatística mostrou que a média de FRVI aumentou significativamente no G1 quando comparado ao G2 (p < 0,05). Conclusão: A aplicação de uma força de 1,5 kg ao espaçador durante a realização da técnica de condensação lateral não produz fraturas radiculares verticais completas, mas pode produzir fraturas incompletas ou “outros defeitos”.