Experimental apical periodontitis alters salivary biochemical composition and induces local redox state disturbances in the salivary glands of male rats.

OBJECTIVES: The objective was to evaluate the effects of experimental apical periodontitis on the inflammatory, functional, biochemical, and redox parameters of the parotid and submandibular glands in rats. MATERIALS AND METHODS: Twenty 12-week-old male Wistar rats were randomly divided into two groups (n = 10): a control group and apical periodontitis group. After 28 days, the saliva was collected for salivary flow rate and biochemistry composition. Both glands were sampled for quantification of the tumor necrosis factor-alpha (TNF-α) and biochemical analyses of redox state. RESULTS: TNF-α concentrations were higher in both salivary glands adjacent to the periapical lesions in animals with apical periodontitis and also compared to the control group. The apical periodontitis group increased the salivary amylase, chloride, potassium, calcium, and phosphate. The total oxidant capacity increased in the parotid gland adjacent to the periapical lesions in the same rat and compared to the control group. Conversely, the total antioxidant capacity of the parotid glands on both sides in the apical periodontitis group was lower than that in the control group. Furthermore, glutathione peroxidase activity increased in the submandibular gland adjacent to the apical periodontitis group compared to the control group. CONCLUSIONS: Experimental apical periodontitis alters salivary biochemical composition, in addition to increasing inflammatory marker and inducing local disturbances in the redox state in the parotid and submandibular glands of male rats. CLINICAL RELEVANCE: Apical periodontitis could exacerbate the decline in oral health by triggering dysfunction in the salivary glands.

Melatonin decreases IRF-3 protein expression in the gastrocnemius muscle, reduces IL-1ß and LPS plasma concentrations, and improves the lipid profile in rats with apical periodontitis fed on a high-fat diet.

To evaluate the effects of melatonin (MEL) on the expression of toll-like receptor-4 (TLR4); myeloid differentiation primary response protein-88 (MyD88); TIR-domain-containing adapter-inducing interferon-ß (TRIF); IFN regulatory-factor-3 (IRF-3); nuclear factor kappa-B (NF-κB); plasma concentrations of interleukin-1ß (IL-1ß) and lipopolysaccharide (LPS); and lipid profile of rats with apical periodontitis (AP) fed on a high-fat diet (HFD). Eighty 60-day-old rats were divided into eight groups: control, AP, HFD, HFDAP, CNMEL, APMEL, HFDMEL and HFDAPMEL. HFD groups were fed on a HFD for 107 days. On day 7, experimental AP was induced in the AP groups, and after 70 days, MEL (5 mg/kg) was administered to the MEL groups for 30 days. Plasma concentrations of LPS and IL-1ß were analyzed using enzyme-linked immunosorbent assay, and the lipid profile was analyzed using biochemical tests. The expression of proteins involved in the TLR4 pathway (TLR4, MyD88, TRIF, IRF-3 and NF-κB) in the gastrocnemius muscle (GM) was evaluated using western blotting and qRT-PCR. Treatment with MEL decreased IRF-3 protein expression in GM and IL-1ß plasma concentration in the APMEL and HFDMEL groups. Reduction in LPS plasma concentration was reported only in the HFDMEL group. Additionally, a decrease in LDL and an increase in HDL were observed in the HFDMEL and HFDAPMEL groups. Treatment with MEL exhibited anti-inflammatory and anti-hyperlipidemic effects attributed to HFD and AP by reducing the plasma concentrations of IL-1ß and LPS in addition to reducing IRF-3 protein expression in the GM, which is associated with the production of inflammatory cytokines.

Biological and antimicrobial properties of the association Ambroxol and a water-soluble viscous liquid as a vehicle for a tricalcium silicate-based sealer.

This study aimed to investigate the antimicrobial and biological properties of Ambroxol associated with glycerin (GLI), propylene glycol (PG), and polyethylene glycol (PEG) as a possible vehicle for an experimental tricalcium silicate sealer, with the intention of developing a new biomaterial. Mouse undifferentiated dental pulp cells (OD-21) were cultured, and the effects of different association on cell proliferation and inflammatory cytokine production were investigated. Antimicrobial adhesion of Enterococcus faecalis to setting sealers at 2 h was evaluated. Polyethylene tubes containing experimental sealers and empty tubes were implanted into dorsal connective tissues of 12 male 3- to 4-months-old Wistar rats (250-280 g). After 7 and 30 days, the tubes were removed and processed for histological and immunohistochemical analyses. ANOVA followed by Bonferroni correction and ANOVA followed by Tukey test was used for parametric data and Kruskal-Wallis followed by Dunn for nonparametric (p < 0.05). Cell proliferation was dose-dependent, since all association were cytotoxic at higher concentrations; however, Ambroxol-PEG showed significantly higher cytotoxicity than other association (p < 0.05). In addition, irrespective of the association, no cytokine production was observed in vitro. Ambroxol-GLI reduced bacterial viability, whereas Ambroxol-PEG increased (p < 0.05). Histological examination showed no significant difference in the inflammatory response (p > 0.05) and mineralization ability in all association. Additionally, IL-1ß and TNF-α were upregulated on Ambroxol-PEG in relation to Control at 07 days (p < 0.05). Ambroxol-GLI was the best vehicle for experimental tricalcium silicate sealer, as it promoted an increase in antimicrobial activity without altering the inflammatory response or mineralization ability.

What is the response profile of deciduous pulp fibroblasts stimulated with E. coli LPS and E. faecalis LTA?

BACKGROUND: Oral fibroblast immunological responses to bacterial stimuli are well known. However, there are few studies about pulp fibroblasts from deciduous teeth (HDPF) responses, which are important for the treatment of pulp infections in children. The aim of this study was to evaluate expression and production of inflammatory cytokines and chemokines by HDPF when challenged with bacterial antigens normally present in advanced caries lesions. METHODS: Triplicate HDPF from 4 children (n = 4; 2 boys and 2 girls) were cultured by explant technique and challenged or not with Escherichia coli lipopolysaccharide/1 µg/mL (EcLPS) or Enterococcus faecalis lipoteichoic acid/1 µg/mL (EfLTA) for 6 and 24 h. Most of published studies employed immortalized cells, i.e., without checking possible gender and genetic variables. mRNA expression and protein production were evaluated by RT-qPCR and ELISA MILLIPLEX®, respectively, for Interleukin (IL)-1α, IL-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-17, Chemokine C-C motif ligand 2/monocyte chemoattractant protein 1 (CCL2/MCP-1), Chemokine C-C motif ligand 3/macrophage inflammatory protein 1-alpha (CCL3/MIP1-α), Chemokine C-C motif ligand 5/ regulated on activation, normal T cell expressed and secreted (CCL5/RANTES), C-X-C motif chemokine 12/ stromal cell-derived factor 1 (CXCL12/SDF-1), Tumor Necrosis Factor-alpha (TNF-α), Interferon-gamma (IFN γ), Vascular Endothelial Growth Factor (VEGF), Colony stimulating factor 1 (CSF-1) and Macrophage colony-stimulating factor (M-CSF). RESULTS: EcLPS increased IL-1α, IL-1ß, IL-8, CCL2, CCL5, TNF-α and CSF-1 mRNA and protein levels while EfLTA was only able to positively regulate gene expression and protein production of IL-8. CONCLUSION: The results of the present study confirmed our hypothesis, since pulp fibroblasts from deciduous teeth are capable of increasing gene expression and protein production after being stimulated with EcLPS and EfLTA.

Endodontic infections increase leukocyte and lymphocyte levels in the blood.

OBJECTIVES: The aim of this study was to determine whether the presence of single or multiple apical periodontitis (AP) alters blood cell counts and cytokine production. MATERIAL AND METHODS: Thirty rats were divided into three groups: a control group comprising rats without AP, a group called 1AP comprising rats with AP in one tooth, and a group called 4AP comprising rats with AP in four teeth. Endodontic infection was induced by pulp exposure of the first right maxillary molar in the 1AP group or by exposing the first and second right maxillary and mandibular molars in the 4AP group. A blood count and cytokine levels were obtained 30 days after infection by collecting blood by cardiac puncture. The maxillae were dissected and stained with hematoxylin and eosin to evaluate the inflammatory infiltrate. The data were tabulated and subjected to statistical analysis (P < 0.05). RESULTS: Histological analysis showed a predominance of mononuclear inflammatory cells. In blood, significant increase of leukocytes, lymphocytes, and tumor necrosis factor alpha (TNF-α) in 4AP compared with the control and 1AP groups (P < 0.05) was observed. In addition, significant decrease of interleukin-4 (IL-4) in 1AP and 4AP groups compared with the control was observed (P < 0.05). CONCLUSIONS: In the rat model, the presence of multiple AP can affect health by increasing lymphocyte and TNF-α levels in the blood. CLINICAL RELEVANCE: The presence of endodontic infections can interfere with the blood profile, altering systemic health.

Biocompatibility of primers and an adhesive used for implant-retained maxillofacial prostheses: An in vitro analysis.

STATEMENT OF PROBLEM: Implant-retained maxillofacial prostheses should be biocompatible, regardless of the primers and adhesives used to bond the acrylic resin and facial silicone. The authors are unaware of any study evaluating the influence of these primers and adhesives on the biocompatibility of maxillofacial prostheses. PURPOSE: The purpose of this in vitro study was to evaluate the cytotoxic effect of primers and an adhesive used to bond acrylic resin and facial silicone during the fabrication of implant-retained maxillofacial prostheses. MATERIAL AND METHODS: Twenty-eight circular specimens made of resin and silicone were fabricated, either bonded or nonbonded with primer and adhesive. The specimens were divided into 7 groups: resin; silicone; resin+silastic medical adhesive type A+silicone; resin+DC 1205 primer silicone; resin+Sofreliner primer+silicone; resin+DC 1205 primer+silastic medical adhesive type A+silicone; and resin+Sofreliner primer+silastic medical adhesive type A+silicone. Eluates of the materials tested were prepared by setting 4 specimens of each experimental group in Falcon tubes with medium and incubating at 37°C for 24 hours. The eluate cytotoxicity was evaluated by an assay of survival/proliferation ((3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide [MTT] test) in cultures of human keratinocytes. The levels of IL1, IL6, TNFα, and the chemokine MIP-1α were evaluated by enzyme-linked immunosorbent assay. The mRNA expressions for MMP-9, TGF-ß, and collagen type IV were analyzed by the real time polymerase chain reaction. Data were submitted to analysis of variance with Bonferroni post hoc tests (α=.05). RESULTS: An increased cell proliferation was observed for the RAS group, with statistically significant differences (P<.001) compared with the unstimulated group. The RDCpS group showed the highest IL6 concentration values (P<.001). No significant statistical difference was found in the relative quantification of mRNA for collagen type IV, MMP9, or TGFß between the groups (P>.05). CONCLUSIONS: The RAS group showed the highest cell proliferation percentage, while the RDCpS group exhibited the highest IL6 concentration values. No detectable levels of IL1ß, TNF α, or CCL3/MIP1α were observed. The tested materials showed no toxic effects on the HaCaT cell line.

Effect of different methods of polymerizing ocular prosthesis acrylic resin on a human conjunctival cell line.

STATEMENT OF PROBLEM: Ocular prosthesis acrylic resins should be biocompatible regardless of the polymerization method. The authors are unaware of a study that evaluated the biocompatibility of ocular prostheses. PURPOSE: The purpose of this in vitro study was to evaluate the cytotoxicity of different methods of polymerizing ocular prosthesis acrylic resin. This was accomplished by analyzing the cell proliferation, production of proinflammatory cytokines, and expression of extracellular matrix proteins related to tissue remodeling and repair of a human conjunctival cell line. MATERIAL AND METHODS: Nine acrylic resin specimens were divided into 3 groups: polymerization in a water bath, by microwave, or by autopolymerization. Eluates (prepared for 72 hours) were exposed to cells for 72 hours. A medium without specimens served as negative control (nonstimulated group). The tetrazolium dye MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay was performed to evaluate the cytotoxic effect, and an enzyme-linked immunosorbent assay was executed for analysis of interleukin 1 ß (IL1ß), IL6, tumor necrosis factor α (TNFα), and CCL3/MIP1α production. Also, real-time reverse transcriptase (RT)-PCR was performed for analysis of mRNA expression of type IV collagen (COL IV), TGFß, and MMP9, and data were tested using ANOVA with Bonferroni post hoc test (α=.05). RESULTS: Microwave-processed resin showed slight cytotoxicity due to a significant reduction in cell proliferation and an increase in IL6 quantity. Higher levels of mRNA expression of COL IV, MMP9, and TGFß were verified in water bath-processed resin, which were similar to those in the nonstimulated group. CONCLUSIONS: Microwave-processed resin showed a significant reduction in cell proliferation and an increase in IL6 quantity. Heat-polymerized resin exhibited a higher mRNA expression of COL IV, MMP9, and TGFß; this result was similar to that in the nonstimulated group.

Losartan Plays a Fungistatic and Fungicidal Activity Against Candida albicans Biofilms: Drug Repurposing for Localized Candidosis.

Candidosis is one of the most frequent opportunistic infections and exhibits variable clinical presentations, including oral localized forms. Drugs affecting the renin-angiotensin system targets inhibit secreted aspartic proteases from Candida albicans. The objective of the study was to evaluate whether losartan has antimicrobial action against C. albicans biofilms. Biofilms were treated with losartan or aliskiren (for comparison) for 24 h. Metabolic activity of viable cells and growth inhibition of C. albicans biofilms were assessed using XTT [2,3-Bis(2-Methoxy-4-Nitro-5-Sulfophenyl)-5-[(Phenyl-Amino)Carbonyl]-2H-Tetrazolium Hydroxide] and colony-forming unit assays, respectively. In addition, the cytotoxicity of the drugs on human cells was evaluated using the AlamarBlue assay. Both drugs decreased fungal viability at all concentrations. In addition, all concentrations of losartan inhibited the growth of C. albicans biofilm, ranging from 47% to 88.5%, whereas aliskiren showed inhibition from 1 to 10 mg/mL, which ranged from 16% to 97.6%. Furthermore, at certain concentrations, these drugs maintained the viability of human cells. Losartan and aliskiren have fungistatic and fungicidal action against C. albicans biofilms and are compatible with human cells. Therefore, these antihypertensive drugs can be repurposed to interfere with the metabolism and development of Candida biofilms, which are widely associated with clinical forms of candidosis, including oral localized forms such as denture stomatitis.

Alterations in salivary biochemical composition and redox state disruption induced by the anticonvulsant valproic acid in male rat salivary glands.

OBJECTIVE: To investigate the effects of the anticonvulsant valproic acid (VPA) on salivary glands in male rat using biochemical, functional, histomorphometric, and redox state parameters. MATERIALS AND METHODS: Twenty-four male Wistar rats were randomly distributed into three groups (n = 8 per group): Control (0.9% saline solution), VPA100 (100 mg/kg), and VPA400 (400 mg/kg). After 21 consecutive days of treatment with by intragastric gavage. Pilocarpine-induced saliva was collected to determine salivary flow rate, pH, buffering capacity, and biochemical composition. Analyses of histomorphometric parameters and redox balance markers were performed on the parotid and submandibular glands. RESULTS: Salivary flow rate, pH, buffering capacity, total protein, potassium, sodium, and chloride were similar between groups. However, phosphate and calcium were reduced in VPA400, while amylase was increased in both VPA100 and VPA400. We did not detect significant differences in the areas of acini, ducts, and connective tissue in the salivary glands between the groups. There were no significant changes in the redox status of the submandibular glands. In turn, in the parotid glands we detected reduced total oxidizing capacity and lipid peroxidation, measured as thiobarbituric acid reactive substances (TBARs) and higher uric acid concentration in both the VPA100 and VPA400 groups, and increased superoxide dismutase (SOD) in the VPA400 group. CONCLUSION: Chronic treatment with VPA modified the salivary biochemical composition and caused disruption in the redox state of the parotid gland in rats.

Effect of nonsteroidal anti-inflammatory drugs (NSAIDs) association on physicochemical and biological properties of tricalcium silicate-based cement.

The aim of this study was to investigate the physicochemical and biological properties of an experimental tricalcium silicate-based repair cement containing diclofenac sodium (CERD). For the physicochemical test, MTA, Biodentine and CERD were mixed and cement disc were prepared to evaluate the setting time and radiopacity. Root-end cavity were performed in acrylic teeth and filled with cements to analyze the solubility up to 7 days. Polyethylene tubes containing cements were prepared and calcium ions and pH were measured at 3h, 24h, 72h and 15 days. For the biological test, SAOS-2 were cultivated, exposed to cements extracts and cell proliferation were investigated by MTT assay at 6h, 24h and 48h. Polyethylene tubes containing cements were implanted into Wistar rats. After 7 and 30 days, the tubes were removed and processed for histological analyses. Parametric and nonparametric data were performed. No difference was identified in relation to setting time, radiopacity and solubility. Biodentine released more calcium ion than MTA and CERD; however, no difference between MTA and CERD were detected. Alkaline pH was observed for all cements and Biodentine exhibited highest pH. All cements promoted a raise on cell proliferation at 24h and 48h, except CERD at 48h. Biodentine stimulated cell metabolism in relation to MTA and CERD while CERD was more cytotoxic than MTA at 48h. Besides, no difference on both inflammatory response and mineralization ability for all cement were found. CERD demonstrated similar proprieties to others endodontic cements available.

Effect of processing methods on the cytotoxicity of methyl methacrylate-based ocular prostheses: An in vitro study.

The study evaluated the influence of cycles and methods of an ocular prosthesis resin on cytotoxicity toward human conjunctival cells. Resins were polymerized by water bath (WB, 74 °C or 100 °C for 30 min to 9 h), microwave (MW, 1200 W, 3 to 14 min and 30 s at 0 to 720 W), or autopolymerization (AP, room temperature for 20 min ± 60 °C for 30 min). Degree of conversion (DC), cytotoxicity, level of inflammatory mediators, gene expression of different markers, and apoptosis were evaluated. Data were submitted to ANOVA and Tukey test (p < 0.05). WB with longer processing time at higher temperature had highest DC (85.6%) and higher TGF ß1-gene expression (1.39); long cycle low power MW showed lowest DC (69.6%), lower cell proliferation (85.4%, MTT), and large IL-2 release (39,297 ng/mL). AP with additional processing time showed lower cell proliferation (75.3%, Alamar Blue), and AP polymerized at room temperature showed higher CASP 9-gene expression (1.21). AP methods showed higher IL-6 release (>277 pg/mL). Short cycle medium power MW had higher IL-23 release (534.2 pg/mL). MW (long and short cycles) and AP polymerizations have triggered a more intense inflammatory response. Among methods recommended by the manufacturer, WB showed high DC and less cytotoxicity.

Mast cells contribute to alveolar bone loss in Spontaneously Hypertensive Rats with periodontal disease regulating cytokines production.

Mast cells (MCs) play a pivotal role in inflammatory responses and had been studied in inflammatory bone disorders, however, their role in alveolar bone loss induced by periodontal disease (PD) is not yet fully understood. We, therefore, aimed to evaluate the effects of MCs depletion in the PD-induced alveolar bone loss in Wistar (W) and Spontaneously Hypertensive Rats (SHRs). PD was induced by ligating the lower first molars with silk thread one day after the MCs depletion, by the pre-treatment with compound 48/80 for 4 days. After 15 days of PD induction, the hemi-mandibles were surgically collected for qRT-PCR, histological analyses, immunostaining, and ELISA. Systolic blood pressure (SBP) was verified by tail plethysmography to confirm the hypertensive status, and SHR presented SBP >150 mmHg, and previous MC depletion alone or associated with PD did not alter this parameter. SHRs showed a more severe alveolar bone loss compared to W, and MC depletion significantly inhibited this response in both strains, with a more significant response in SHRs. MCs were less abundant in 48/80+PD groups, thus validating the previous MCs depletion in our model. PD increased the number of MC in the gingival tissue of SHR. Cytokine production (TNF-α, IL-6, IL-1ß, and CXCL3) was constitutively higher in SHR and increased further after PD, which was also significantly reduced in the MCs-depleted animals. PD led to an increased expression of Opn, Rankl, Rank, Vtn, Itga5, Itgb5, Trap, and Ctsk in the mandible of W and SHRs, which was reversed in MCs-depleted animals. These results suggest that MCs significantly contributes to the PD-induced alveolar bone resorption, especially in the SHR, which is associated with a more severe PD progression compared to Wistar, partly explained by these cells contribution to the inflammatory status and mediator production, stimulating osteoclast-related response markers, which were reduced after MC depletion in our experimental model.

Biocompatible silver nanoparticles incorporated in acrylic resin for dental application inhibit Candida albicans biofilm.

BACKGROUND: Although silver nanoparticles (SNP) have proven antimicrobial activity against different types of microorganisms, the effect of SNP incorporation into acrylic resin to control Candida albicans biofilm formation aiming at the prevention of Candida-associated denture stomatitis has not yet been fully elucidated. OBJECTIVES: This study aimed to evaluate the antimicrobial effect of an acrylic resin containing SNP on C. albicans biofilm growth, the flexural strength of this material and tissue reaction in the subcutaneous connective tissue of rats to SNP. METHOD: SNP were synthesized through silver nitrate reduction by sodium citrate. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used to verify the size and colloidal stability. SNP were added to acrylic resin monomer (Lucitone 550) at 0.05, 0.5 and 5 vol%. The antimicrobial effect against C. albicans (ATCC 10231) was investigated by the enumeration of colony-forming units (CFUs) and SEM. The three-point bending test was performed to analyze the flexural strength. Tissue reaction was evaluated after 7 and 60 days of implantation in the connective tissue of Wistar rats. RESULTS: Spherical particles of 5 and 10 nm were obtained. SNP at 0.05 and 0.5% incorporated into acrylic resin was effective in reducing C. albicans biofilm growth (p < .001). SEM revealed that the material was able to disrupt C. albicans biofilm formation and did not reduce the flexural strength compared to control (p > .05). The inflammatory response observed 60 days after implantation SNP in the subcutaneous tissue was similar to control. CONCLUSION: It was concluded that SNP addition at 0.05 and 0.5% into acrylic resin exhibited antimicrobial effects against C. albicans biofilm, did not interfere in the flexural strength and may be considered biocompatible.

Antimicrobial, antibiofilm and cytotoxic effects of a colloidal nanocarrier composed by chitosan-coated iron oxide nanoparticles loaded with chlorhexidine.

OBJECTIVES: This study evaluated the antimicrobial and antibiofilm effects of a colloidal nanocarrier for chlorhexidine (CHX) on Candida glabrata and Enterococcus faecalis, as well as tested its cytotoxic effect on murine fibroblasts. METHODS: Iron oxide nanoparticles (IONPs) were coated with chitosan (CS) and loaded with CHX at 31.2, 78 and 156 µg/mL. Antimicrobial effects were assessed by determining the minimum inhibitory concentration (MIC), using the broth microdilution method, and fractional inhibitory concentration index (FICI). Preformed biofilms (48 h) were treated with different concentrations of the nanocarrier (24 h) and quantified by colony-forming units (CFUs), total biomass and metabolic activity. For cytotoxicity, the viability of L929 cells was evaluated by MTT assay after 24 and 48 h of exposure to the nanocarrier. Data were submitted to ANOVA and Fisher LSD or Tukey post-hoc tests (α = 0.05). RESULTS: MIC and FICI results showed an indifferent interaction among the components of the nanocarrier for all strains evaluated. CHX alone and nanocarrier containing 156 µg/mL CHX did not differ from each other in reducing the number of CFUs. However, the nanocarrier containing 156 µg/mL CHX promoted the highest reductions in total biofilm biomass and metabolism, surpassing the effect of CHX alone. After 24 and 48 h of exposure, the nanocarrier reduced CHX toxicity to the L929 cell at low concentrations. CONCLUSION: These findings suggest that the CHX nanocarrier has potential to be used in the control of oral diseases associated with C. glabrata and E. faecalis. CLINICAL RELEVANCE: CHX has improved the antibiofilm effect and reduced the cytotoxicity (at low concentrations) when conjugated to CS-coated IONPs. This new colloidal formulation has potential as an alternative antimicrobial agent to pure CHX for the control of biofilm-related oral diseases, such as oral candidiasis and endodontic infections.

Telmisartan Prevents Alveolar Bone Loss by Decreasing the Expression of Osteoclasts Markers in Hypertensive Rats With Periodontal Disease.

Periodontal disease (PD) is a prevalent inflammatory disease with the most severe consequence being the loss of the alveolar bone and teeth. We therefore aimed to evaluate the effects of telmisartan (TELM), an angiotensin II type 1 receptor (Agtr1) antagonist, on the PD-induced alveolar bone loss, in Wistar (W) and Spontaneous Hypertensive Rats (SHRs). PD was induced by ligating the lower first molars with silk, and 10 mg/kg TELM was concomitantly administered for 15 days. The hemimandibles were subjected to microtomography, ELISA was used for detecting tumor necrosis factor (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6), CXCL3, and CCL2, while qRT-PCR was used for analyzing expression of components of renin-angiotensin system (RAS) (Agt, Ace, Agt1r, Agt2r, Ace2, and Masr), and bone markers (Runx2, Osx, Catnb, Alp, Col1a1, Opn, Ocn, Bsp, Bmp2, Trap, Rank, Rankl, CtsK, Mmp-2, Mmp-9, and osteoclast-associated receptor (Oscar)). The SHR + PD group showed greater alveolar bone loss than the W + PD group, what was significantly inhibited by treatment with TELM, especially in the SHR group. Additionally, TELM reduced the production of TNF-α, IL-1ß, and CXCL3 in the SHR group. The expression of Agt increased in the groups with PD, while Agtr2 reduced, and TELM reduced the expression of Agtr1 and increased the expression of Agtr2, in W and SHRs. PD did not induce major changes in the expression of bone formation markers, except for the expression of Alp, which decreased in the PD groups. The bone resorption markers expression, Mmp9, Ctsk, and Vtn, was higher in the SHR + PD group, compared to the respective control and W + PD group. However, TELM attenuated these changes and increased the expression of Runx2 and Alp. Our study suggested that TELM has a protective effect on the progression of PD, especially in hypertensive animals, as evaluated by the resorption of the lower alveolar bone. This can be partly explained by the modulation in the expression of Angiotensin II receptors (AT1R and AT2R), reduced production of inflammatory mediators, the reduced expression of resorption markers, and the increased expression of the bone formation markers.

Cytotoxicity and inflammatory response of different types of provisional restorative materials.

AIM: To evaluate the cytotoxicity and inflammatory response of different types of provisional restorative materials to mice gingival fibroblasts. METHODS: Cytotoxicity of provisional material discs (thermal-polymerized acrylic resin; auto-polymerized acrylic resin; bisacrylic resin; nano-ceramic resin for CAD/CAM and prefabricated polymer block for CAD/CAM) to Mice (Balb/c) gingival cell were investigated under direct and indirect contact (extracts) at 24, 48 and 72 h, using the MTT and Alamar blue assays. Materials extracts (24 h) were applied to the cell culture (indirect contact) or cells were seeded on discs of provisional materials, and the cytotoxicity and production of IL-6, IL-1ß and TNF-α after 24, 48 and 72 h were analyzed through MTT, Alamar Blue® and ELISA. Culture medium was used as control for indirect contact assay (extract) and the surfaces of the wells without discs of provisional materials were used as control for direct contact assay. Results were analysed statistically by ANOVA followed by the Bonferroni-Test correction. Statistically significant differences were considered if P was < .05. RESULTS: Auto-polymerized and bisacrylic resins (direct contact) reduced cell viability after 24, 48 and 72 h compared to control (P < .05). Indirect contact (extract) was not cytotoxic to cells at all periods compared to control (P > .05). Auto-polymerized and bisacrylic resins increased IL-6, IL-1ß and TNF-α levels mainly at 24 h when compared to the other materials (P < .001). CONCLUSION: Auto-polymerized and bisacrylic were more cytotoxic to mice gingival fibroblasts. CAD/CAM nano ceramic resin and prefabricated polymer blocks are more predictable materials to preserve the periodontal soft tissues.

Cytotoxicity and antimicrobial effects of citronella oil (Cymbopogon nardus) and commercial mouthwashes on S. aureus and C. albicans biofilms in prosthetic materials.

Although the effectiveness of some mouthwashes has been proven, phytotherapy is still a field to be explored as an alternative to commercial products. OBJECTIVE: To evaluate, in vitro, the cytotoxicity and efficacy of two solutions based on citronella oil (CN), on S. aureus and C. albicans biofilms (in formation-adhesion phase and 24 h-biofilm formation) on acrylic resin and nickel-chromium alloy samples (one trademark of each material), compared to two alcohol-free commercial mouthwashes. MATERIAL AND METHODS: Two solutions containing CN at concentrations of 5x and 10x the minimum bactericidal/fungicidal concentration (MBC/MFC) were prepared by microdilution. After contamination of the samples surfaces with these microorganisms, the mouthwashes (CN - 5x and 10x; CHX - 0,12% alcohol-free chlorhexidine and LT - alcohol-free essential oils) were evaluated. Mouthwash simulation was performed for 1 min at two moments, the first simulation after 4 h of microbial adhesion and 24 h-biofilm formation, and the second simulation, 6 h after the first simulation. For biofilm quantification, the number of cultured cells was evaluated by CFUs. The cytotoxicity assay was performed on HaCat epithelial cells and quantified by the MTT method. RESULTS: Tested solutions completely inhibited the growth of both microorganisms in the adhesion phase. All solutions showed inhibitory activity against 24 h-biofilm formation. However, CN led to greater microbial reduction, regardless of the surface of the sample. All solutions demonstrated a toxic effect. However, after serial dilution, CN presented the lowest cytotoxic effect. CONCLUSION: Citronella had a lower cytotoxic effect and a higher action compared to commercial solutions.

Cytotoxicity and biocompatibility of a new bioceramic endodontic sealer containing calcium hydroxide.

This study evaluated the cytotoxicity and biocompatibility of a new bioceramic endodontic sealer (i.e., Sealer Plus BC) in comparison with those of MTA Fillapex and AH Plus. L929 fibroblasts were cultured and Alamar Blue was used to evaluate cell viability of diluted extracts (1:50, 1:100, and 1:200) from each sealer at 24 h. Polyethylene tubes that were filled with material or empty (as a control) were implanted in the subcutaneous tissue of rats. The rats were killed after 7 and 30 d (n = 8), and the tubes were removed for histological analysis. Parametric data was analyzed using a one-way ANOVA test, and nonparametric data was analyzed via the Kruskal-Wallis test followed by the Dunn test (p < 0.05). A reduction in cell viability was observed in the extracts that were more diluted for Sealer Plus BC when compared to that of Control and AH Plus (p < 0.05). However, the 1:50 dilution of the Sealer Plus BC was similar to that of the Control (p > 0.05). Conversely, more diluted extracts of MTA Fillapex (1:200) and AH Plus (1:100 and 1:200) were similar to the Control (p > 0.05). Histological analysis performed at 7 d did not indicate any significant difference between tissue response for all materials, and the fibrous capsule was thick (p > 0.05). At 30 d, Sealer Plus BC was similar to the Control (p > 0.05) and MTA Fillapex and AH Plus exhibited greater inflammation than the Control (p < 0.05). The fibrous capsule was thin for the Control and for most specimens of Sealer Plus BC and AH Plus. Thus, Sealer Plus BC is biocompatible when compared to MTA Fillapex and AH Plus, and it is less cytotoxic when less-diluted extracts are used.

Aliskiren Attenuates the Inflammatory Response and Wound Healing Process in Diabetic Mice With Periodontal Disease.

The aim of this study was to characterize the role of local RAS (renin-angiotensin system) in the inflammatory response of normal (N) and diabetic (D) mice with periodontal disease (PD). Diabetes Mellitus (DM) was induced by peritoneal injection of streptozotocin in Balb/c mice. PD was induced by ligature around the first molar in both N and D, irrespective of whether they were treated with aliskiren (50 mg/kg, Alisk). Mandibles were harvested for histomorphometric analyses, and gingival tissue (GT) was collected to evaluate gene expression and extracellular matrix components (ECM). Immunohistochemical (IHC) analyses were used to localize RAS in GT. The production of C-reactive protein (CRP), IL-1ß, CXCL2, and CCL8 was evaluated by enzyme-linked immunosorbent assay (ELISA). Renin was found to exacerbate the inflammation and periodontal bone loss at 14 days after PD, and Alisk inhibited this process in GT of N and D. PD increased CRP, CXCL2, CCL8, and IL-1ß production in both animals. Alisk could inhibit CRP, CXCL2, and CCL8 primarily in D animals. However, only CCL8 was decreased in N animals after Alisk pretreatment. PD enhanced expression and production of AGT, ACE, AT1R, and AT2R in both N and D. AT1R expression was higher in D with PD, and AT2R expression was higher in N with PD. ACE2 and receptor Mas (MasR) expression and production was elevated in the control group of both animals. PD inhibited ACE2 in N but not in D. MasR expression was unaffected in both N and D with PD. Alisk reduced expression and production of all RAS components in GT of both animals, except for ACE2 in N. RAS staining was observed in all layers of epithelium, basal cell layer, and lamina propria and was higher in N with PD. Col1a1, Col1a2, Col3a1, and fibronectin (Fn1) were increased in both animals with PD. Alisk inhibited Col1a1 and Fn in both animals, Col1a2 was decreased only in D, while levels of Col3a1 remained unchanged in all animal groups. In conclusion, these data demonstrated the presence and functional role of local RAS in GT, exacerbating the inflammatory response, periodontal bone loss, and wound healing processes in both N and D animal groups. In addition, Alisk was able to significantly reduce gingival inflammation, excessive wound healing processes, and periodontal bone loss.

Cytotoxicity, Biocompatibility and Biomineralization of a New Ready-for-Use Bioceramic Repair Material.

New mineral trioxide aggregate (MTA) formulations are constantly introduced in the market, usually in a powder-and-liquid form. Bioceramic (Bio-C) Repair is a ready-for-use material suggested as substitute for MTA, but its properties need to be studied. This study evaluated the cytotoxicity, biocompatibility and biomineralization of Bio-C Repair compared to MTA Repair High-Plasticity (MTA-HP) and white MTA-Angelus (MTA-Ang). L929 fibroblasts were exposed to material-extracted (undiluted, ½ and » dilutions; 6, 24 and 48h). Polyethylene tubes with material or empty (control) were implanted in the subcutaneous tissue of rats. After 7 and 30 days (n=8), the specimens were removed for analysis (hematoxylin-eosin, von Kossa and polarized light). Cytotoxicity data were statistically analyzed by two-way ANOVA, and biocompatibility data by Kruskal-Wallis and Dunn tests (p<0.05). The cells exposed to the materials had greater viability at most of the periods compared with control (p<0.05). The undiluted and ½ dilutions of MTA-HP extract showed higher cytocompatibility than Bio-C Repair at 6 h and with the » dilution at 24 h (p<0.05); the white MTA-Ang showed higher cytocompatibility than Bio-C Repair at most of periods (p<0.05). The undiluted white MTA-Ang extract had higher cytocompatibility at 6 and 24h than MTA-HP, and with ½ dilution at 24h (p<0.05). The materials' cytocompatibility was similar at 48h for most dilutions (p>0.05). At 7 and 30 days, the groups had moderate and mild inflammation, respectively (p>0.05). All materials showed positive structures for von Kossa and polarized light. In conclusion, Bio-C Repair had similar cytocompatibility to MTA-based materials is biocompatible and induces biomineralization.