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The lipopolysaccharides-dentine-infection (LPS-dentine-infection) models and sampling techniques frequently used to evaluate LPS disinfection have limitations. In this study, a LPS-dentine-infection model was devised using fluorescent conjugate LPS. Secondly, a sampling technique using cryogenic grinding for intraradicular LPS analysis was evaluated. Thirdly, the effectiveness of the XP-endo Finisher (XP-EF) was compared with passive ultrasonic irrigation (PUI) in removing LPS from root canal system.Sixty-nine mandibular premolars were submitted to dentine pretreatment and inoculated with fluorescent LPS conjugate (Alexa Fluor® 594). Twenty-three teeth were analysed under confocal laser scanning microscopy (CLSM) to validate this modified LPS-dentine-infection model. Forty-six teeth were randomly divided into two experimental groups: XP-EF (n = 23) and PUI (n = 23). All teeth were instrumented with XP-endo shaper (XPS; FKG Dentaire) and 2.5% NaOCl. The root canals were sampled with paper points before (s1) and after (s2) instrumentation and after supplemental treatment (s3) with XP-EF and PUI. After s3, all roots were cryogenically ground for intraradicular LPS analysis (s4). Limulus amebocyte lysate assay was used for LPS quantification. The Friedman test was used for differences in LPS among four time-points (s1, s2, s3, and s4). Dunn's test was used for pairwise testing of time-points. The significance level was set at 5% (p .05).Fluorescent LPS conjugate was detected in 100% of the samples under CLSM with a penetration depth of approximately 400 μm into dentine. Chemo-mechanical preparation using XPS files significantly reduced LPS levels (p .05). Both the XPS and PUI improved the LPS disinfection (p .05), with no difference between them (p .05). LPS was recovered from all samples after cryogenic grinding. The residual amount of LPS detected using the cryogenically sampling technique at s4 was approximately three times greater than with the paper-point sampling technique at s3.This study established a modified LPS-dentine-infection model using fluorescent conjugate LPS, and validated a LPS sampling technique for using cryopulverization intraradicular LPS analysis. Moreover, both the XP-EF and PUI further improved LPS disinfection from the root canals, and the innovative XP-EF was as effective as PUI.

Introduction: This Consolidated Standards of Reporting Trials randomized clinical trial investigated T helper (Th1, Th2, Th9, Th17, and Tfh) and regulatory T (Treg) cell–type cytokines and their networks in apical periodontitis (AP). We also assessed the effects of calcium hydroxide [Ca(OH)2] intracanal medications (ICMs) on helper T and Treg cell–type cytokines. Methods: Twenty teeth with primary endodontic infection and apical periodontitis were randomly divided into two groups: Ca(OH)2 + saline solution (n = 10) and Ca (OH)2 + 2% chlorhexidine-gel (n = 10). Samples were collected from the periradicular tissue fluid (PTF) before (PTFs1) and after 14 days of ICMs (PTFs2). The Human High Sensitivity T Cell Panel was used to quantify target T-helper (Th)1: interelukin (IL)-2, IL-12, and interferon-gamma (IFN-γ); Th2: IL-4, IL-5, and IL-13; Th9: IL-9; Th17: IL-17; T follicular helper cells (Tfh): IL-21; and Treg-cell-type cytokine: IL-10. Results: Th1-type cytokines were higher than Th2-type ones, at PTFs1. Positive (+) associations were found among all Th1-type cytokines and all Th2-type cytokines. There were negative (-) correlations between all Th1- and Th2-type cytokines. Size of radiolucent lesions and symptoms (tenderness to percussion and/or pain on palpation) were positively correlated with Th1-type cytokines, IL-17, and IL-21 but negatively correlated with Th2-type cytokines and IL-10 (all, P .05). Conclusions: Complex T-cell cytokine networks are involved in AP. Both Ca(OH)2 ICMs effectively increased IL-4, IL-5, IL-10, and IL-13 and lowered IL-2, IL-12, IL-17, IL-21, and IFN-γ.

Introduction The purpose of this study was to investigate the accuracy and efficiency of the 3-dimensional dynamic navigation system (DNS) compared with the freehand technique (FH) when removing fiber posts from root canal–treated teeth. Methods Twenty-six maxillary teeth were included. Teeth were root canal treated and restored with Parapost Taper Lux (Coltene/Whaledent, Altstatten, Switzerland) luted with RelyX Unicem (3M ESPE, St Paul, MN). A core buildup was then performed using Paracore (Coltene/Whaledent). Teeth were mounted in tissue-denuded cadaver maxillae. Teeth were divided into 2 groups: the DNS group (n = 13) and the FH group (n = 13). Cone-beam computed tomographic scans were taken pre- and postoperatively. The drilling path and depth were planned virtually using X-guide software (X-Nav Technologies, Lansdale, PA) in both groups. For the DNS group, drilling was guided with X-Nav software and the FH group under a dental operating microscope. Global coronal and apical deviations, angular deflection, operation time, and the number of mishaps were compared between the groups to determine the accuracy and efficiency. The 3-dimensional volume (mm3) of all teeth was calculated before and after post removal using the Mimics Innovation Suite (Materialise NV, Leuven, Belgium). The Shapiro-Wilk, 1-way analysis of variance, and Fisher exact tests were used (P Results The DNS group showed significantly less global coronal and apical deviations and angular deflection than the FH group (P Conclusions The DNS was more accurate and efficient in removing fiber posts from root canal–treated teeth than the FH technique.

To determine and compare the accuracy and efficiency of a dynamic navigation system (DNS) with a freehand (FH) technique when conducting root-end resection in a human cadaver model.Forty roots in cadaver heads were included and divided into two groups: DNS (n = 20) and FH (n = 20). Cone beam computed tomography (CBCT) scans of all teeth were taken. The drilling path and depth were planned virtually to using the X-guide software (X-Nav Technologies, Lansdale, PA, USA). Osteotomy and root-end resection were done under navigation in the DNS group, and freehand under the dental operating microscope in the FH group. Post-operative CBCTs were taken. Linear deviations, angular deflection, time of operation and number of mishaps were compared with determine the accuracy and efficiency. Shapiro-Wilk, one-way ANOVA and Fisher exact tests were used (P 0.05).Linear deviations, angular deflection and operation time were significantly less in the DNS group (P 0.05). The number of mishaps was not different between the two groups (P 0.05). Subgroup analyses revealed that the distance of5 mm from buccal cortical plate was significantly associated with lower accuracy, increased operation time and greater incidence of mishaps in the FH group (P 0.05), but not in the DNS group.The dynamic navigation system was more accurate and more efficient in root-end resection in a cadaver model than the freehand technique. The distance of the roots from the buccal cortical plate had a significant negative impact on the accuracy and efficacy of the root-end resection procedure when using the freehand technique. The dynamic navigation system has the potential to be a safe and reliable technological addition to endodontic microsurgery.

Sepsis is a leading cause of death in the United States, with a mortality rate in excess of 215,000 deaths per year. It may lead to septic shock, a complex pathophysiological process with microbial and host response events that progress to multisystem derangement. There is poor documentation of the relationship between dental infection and septic shock, with only a few case reports of septic shock secondary to dentoalveolar abscess. Presented is a case of sepsis/septic shock in a 23-year-old man with signs and symptoms of pulpal necrosis, acute apical abscess, and canine space infection that rapidly progressed to an altered mental state, hyperthermia, tachycardia, hypotension, acute respiratory failure, diarrhea, renal insufficiency, lactic acidosis, leukocytosis, and hyperglycemia. Once septic shock develops, the mortality rate is nearly 50%. Early antimicrobial intervention is associated with surviving severe sepsis, making it critical for dentists to understand local factors leading to the crisis and the signs and symptoms of the sepsis–septic shock continuum.

Made available in DSpace on 2022-04-28T19:52:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-12-01 This study compared the effectiveness of GentleWave system (GWS) and passive ultrasonic irrigation (PUI) in removing lipopolysaccharides (LPS) from infected root canals after minimally invasive (MIT) and conventional instrumentation (CIT) techniques. Sixty first premolars with two roots were inoculated with fluorescent LPS conjugate (Alexa Fluor 594). Of those, twelve were dentin pretreated, inoculated with fluorescent LPS conjugate, and submitted to confocal laser scanning microscopy (CLSM) to validate the LPS-infection model. Forty-eight teeth were randomly divided into treatment groups: GWS + MIT, GWS + CIT, PUI + MIT, and PUI + CIT (all, n = 12). Teeth were instrumented with Vortex Blue rotary file size 15/0.04 for MIT and 35/0.04 for CIT. Samples were collected before (s1) and after a root canal procedure (s2) and after cryogenically ground the teeth (s3) for intraradicular LPS analysis. LPS were quantified with LAL assay (KQCL test). GWS + MIT and GWS + CIT were the most effective protocols against LPS, with no difference between them (p > 0.05). PUI + CIT was more effective than PUI + MIT (p < 0.05) but less effective than GWS + MIT and GWS + CIT. GWS was the most effective protocol against LPS in infected root canals using MIT and CIT techniques. Division of Endodontics Department of Advanced Oral Sciences and Therapeutics University of Maryland School of Dentistry Department of Restorative Dentistry Endodontic Division São Paulo State University (Unesp) Institute of Science and Technology Department of Social and Pediatric Dentistry Institute of Science and Technology São Paulo State University (Unesp) Institute of Science and Technology Department of Restorative Dentistry Endodontic Division São Paulo State University (Unesp) Institute of Science and Technology Department of Social and Pediatric Dentistry Institute of Science and Technology São Paulo State University (Unesp) Institute of Science and Technology

The aim of the study is to investigate whether the 3-dimensional dynamic navigation system (3D-DNS) can improve experienced endodontists' (EEs') and novice endodontists' (NEs') accuracy and efficiency in osteotomy and root-end resection (RER) and to verify that the 3D-DNS enables NEs to perform osteotomy and RER as accurately and efficiently as EEs.Seventy-six roots in cadaver heads were randomly divided into 4 groups: 3D-DNS-NE, 3D-DNS-EE, freehanded (FH)-NE, and FH-EE (all, n = 19). Cone-beam computed tomography scans were taken preoperatively and postoperatively. Osteotomy and RER were planned virtually in the X-guided software (X-Nav Technologies, Lansdale). Accuracy was calculated by measuring the 2-dimensional and 3D virtual deviations and angular deflection using superimposing software (X-Nav technologies). Efficiency was determined by the time of operation and the number of mishaps.Accuracy deviations were significantly fewer in the 3D-DNS-EE group than those in the FH-EE group (P .05). We found less 2-dimensional and 3D accuracy deviations comparing the 3D-DNS-NE group to the FH-NE group (P .05). The time required for osteotomy and RER with the 3D-DNS was ∼ ½ of that required for the FH method for both EEs and NEs (P .05). We found no difference in the number of mishaps between the 3D-DNS and FH groups for EEs and NEs (P .05).The 3D-DNS improved EEs' and NEs' accuracy and efficiency in osteotomy and RER. The NEs were as efficient as the EEs using the 3D-DNS. Notably, the 3D-DNS improved the NEs' accuracy compared to the FH method, but the 3D-DNS did not enable the NEs to perform osteotomy and RER as accurately as the EEs.

This study evaluated the effectiveness of the GentleWave System (GWS; Sonendo, Laguna Hills, CA) and passive ultrasonic irrigation (PUI) in removing Enterococcus faecalis lipoteichoic acid (LTA) from infected root canals with a minimally invasive technique (MIT) and the conventional instrumentation technique (CIT).Sixty extracted human maxillary first premolars were included. All teeth were dentin pretreated and inoculated with LTA prepared from E. faecalis. First, 12 teeth were cryogenically ground to investigate the viability of recovering intraradicular E. faecalis LTA. Afterward, 48 teeth were randomly divided into the following groups: GWS + MIT, GWS + CIT, PUI + MIT, and GWS + CIT (all n = 12). Teeth were instrumented with a Vortex Blue (Dentsply Sirona, Ballaigues, Switzerland) rotary file size 15/.04 for MIT and 35/.04 for CIT. Samples were collected before and after a root canal procedure with sterile/apyrogenic paper points and after cryogenically ground for intraradicular LTA analysis. LTA was quantified with an LTA enzyme-linked immunosorbent assay kit.E. faecalis LTA was recovered from 100% of the samples (48/48) before the root canal procedure. GWS + MIT and GWS + CIT were the most effective protocols against E. faecalis LTA, with no difference between them (P.05). PUI + CIT was more effective than PUI + MIT (P.05) but less effective than GWS + MIT and GWS + CIT (P.05). The GWS groups showed more root canals with undetected E. faecalis LTA after treatment than all groups tested.GWS + MIT and GWS + CIT were the most effective protocols against E. faecalis LTA in infected root canals.

Introduction: We verified the association between selected bacterial profiles and levels of cytokines, chemokines, and the expression of signs and symptoms of primary endodontic infection with apical periodontitis. Methods: Samples were collected from 21 root canals, and macrophages were stimulated for 24 hours. Tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, IL-10, IL-12p70, interferon gamma, and chemokine (C-C motif) ligand 2 (CCL2) were measured using cytometric bead array. We investigated the overlapping networks between cytokines and chemokines with regression analysis. Checkerboard DNA-DNA hybridization was used to assess 40 target bacteria species. Using factor analysis, bacterial species aggregated in 2 factors. The association of bacteria species–based factors on cytokine and chemokine levels and clinical features was estimated with regression analysis. Results: A negative relationship between IL-10 (anti-inflammatory cytokine) and CCL2, TNF-α, and IFN-γ (proinflammatory cytokines) (all P

Made available in DSpace on 2021-06-25T10:15:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-02-01 This case report describes the resolution of a 20-year misdiagnosed nasal sinus tract after root canal therapy with multiple sessions of calcium hydroxide (Ca[OH]2) intracanal medication. Clinical evaluation, including diagnostic testing and sinus tract tracing, was performed followed by a cone-beam computed tomographic scan and 3-dimensional reconstruction of the apical lesion. Bacteria and endotoxin analyses were performed from the nasal sinus tract and paired root canal infection before (s1) and after instrumentation (s2) and after 7 (s3), 14 (s4), and 21 (s5) days of Ca(OH)2 medication. The bacteria analysis was performed using the checkerboard DNA-DNA hybridization method and endotoxin quantified by the limulus amebocyte lysate method. A similar microbiota profile was found in the sinus tract and paired root canal infection. No target bacterial species were detected in the root canal at s2, s3, and s5. In contrast, Actinomyces israellii and Eubacterium nodatum were detected at s4. Differences in bacterial detection were found between s1 × s2, s3 × s4, and s4 × s5 (all P

This study investigated the influence of calcium hydroxide intracanal medications on the levels of metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in apical periodontitis (AP).Twenty primarily infected root canals with AP were randomly divided into two groups: Ca(OH)MMP-1, MMP-2, MMP-9, TIMP-1, and TIMP-2 were detected in all PTF samples at s1 and s2 (20/20). At s1, MMP-2 and MMP-9 were detected at higher levels than MMP-1 (p .05). Higher levels of TIMP-1 than TIMP-2 were found in AP (p .05). Additionally, we detected higher MMP-1, MMP-2, and MMP-9 over TIMP-1 and TIMP-2 levels in AP (p .05). At s2, Ca(OH)Calcium hydroxide medications effectively lowered the levels of MMP-1, MMP-2, and MMP-9 in periapical tissues after 14 days of treatment, with no difference between them. Moreover, the calcium hydroxide intracanal medications tested here had no impact in TIMP-1 and TIMP-2 in periapical tissues.MMPs and TIMPs play an essential role in the degradation of the extracellular matrix. The imbalance MMPs and TIMPs can cause periapical tissue destruction. Therefore, the reestablishment of the balance between activated MMPs and TIMPs with root canal therapy is essential to restore tissue homeostasis.

Aims (1) To investigate aerosolized microorganisms generated during endodontic emergencies and non—surgical root canal therapy (NSRCT); (2) To assess how far airborne microbial spread; and (3) To verify the spatial distribution of airborne microbial spread. Methods A total of 45 endodontic procedures were sampled, including full pulpotomy (n=15), pulpectomy (n=15), and NSRCT (n=15). Samples were collected during room resting (s1) and after the treatment (s2). The passive air sampling technique using settle plates was applied. Agar plates were set at different locations in the operatory. The colony-forming unit (CFU) was counted in BHI blood agar plates. A set of agar plates containing selective chromogenic culture media was used for the isolation and presumptive identification of target microorganisms. Fungi were investigated using Sabouraud Dextrose Agar. Results Pulpotomy generated the lowest mean CFU count (p0.05). A higher mean CFU count was found close to the patient’s mouth (0.5m) than at a 2m distance in pulpectomy and NSRCT (P0.05). S. aureus (22/ 45, 48.8%) was the most frequent bacteria species. Longer treatment times were associated with higher CFU counts. Conclusion Our findings indicated that pulpotomy generates less aerosolized microorganisms than pulpectomy and NSRCT. Moreover, the proximity to the patient’s mouth and the treatment duration implicated in the level of contamination.

The aims are: (a) To develop the first low-shrinkage-stress nanocomposite with antibacterial and remineralization capabilities through the incorporation of dimethylaminododecyl methacrylate (DMAHDM) and nanoparticles of amorphous calcium phosphate (NACP); (b) to investigate the effects of the new composite on biofilm inhibition, mechanical properties, shrinkage stress, and calcium (Ca) and phosphate (P) ion releases. The low-shrinkage-stress resin consisted of urethane dimethacrylate and triethylene glycol divinylbenzyl ether. Composite was formulated with 3% DMAHDM and 20% NACP. Mechanical properties, shrinkage stress, and degree of conversion were evaluated. Streptococcus mutans biofilm growth on composites was assessed. Ca and P ion releases were measured. The shrinkage stress of the low-shrinkage-stress composite containing 3% DMAHDM and 20% NACP was 36% lower than that of traditional composite control (p < 0.05), with similar degrees of conversion of 73.9%. The new composite decreased the biofilm colony-forming unit by 4 log orders and substantially reduced biofilm lactic acid production compared to control composite (p < 0.05). Incorporating DMAHDM to the low-shrinkage-stress composite did not adversely affect the Ca and P ion release. A novel bioactive nanocomposite was developed with low shrinkage stress, strong antibiofilm activity, and high levels of ion release for remineralization, without undermining the mechanical properties and degree of conversion.

Caries-related biofilms and associated complications are significant threats in dentistry, especially when biofilms grow over dental restorations. The inhibition of cariogenic biofilm associated with the onset of carious lesions is crucial for preventing disease recurrence after treatment. This in vitro study defined optimized parameters for using a photosensitizer, toluidine blue O (TBO), activated via a red light-emitting diode (LED)-based wireless device to control the growth of cariogenic biofilms. The effect of TBO concentrations (50, 100, 150, and 200 &mu, g/mL) exposed to light or incubated in the dark was investigated in successive cytotoxicity assays. Then, a mature Streptococcus mutans biofilm model under sucrose challenge was treated with different TBO concentrations (50, 100, and 150 &mu, g/mL), different light energy doses (36, 108, and 180 J/cm2), and different incubation times before irradiation (1, 3, and 5 min). The untreated biofilm, irradiation with no TBO, and TBO incubation with no activation represented the controls. After treatments, biofilms were analyzed via S. mutans colony-forming units (CFUs) and live/dead assay. The percentage of cell viability was within the normal range compared to the control when 50 and 100 &mu, g/mL of TBO were used. Increasing the TBO concentration and energy dose was associated with biofilm inhibition (p &lt, 0.001), while increasing incubation time did not contribute to bacterial elimination (p &gt, 0.05). Irradiating the S. mutans biofilm via 100 &mu, g/mL of TBO and &asymp, 180 J/cm2 energy dose resulted in &asymp, 3-log reduction and a higher amount of dead/compromised S. mutans colonies in live/dead assay compared to the control (p &lt, 0.001). The light energy dose and TBO concentration optimized the bacterial elimination of S. mutans biofilms. These results provide a perspective on the determining parameters for highly effective photo-killing of caries-related biofilms and display the limitations imposed by the toxicity of the antibacterial photodynamic therapy&rsquo, s chemical components. Future studies should support investigations on new approaches to improve or overcome the constraints of opportunities offered by photodynamic inactivation of caries-related biofilms.

Objective: This review clusters the growing field of nano-based platforms for antimicrobial photodynamic therapy (aPDT) targeting pathogenic oral biofilms and increase interactions between dental r...

Made available in DSpace on 2021-06-25T10:12:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Aim: To investigate the presence of resolvins E1 (RvE1) and D2 (RvD2) in teeth with primary endodontic infections and apical periodontitis, and to assess the influence of calcium hydroxide medication [Ca(OH)2], in association with 2% chlorhexidine gel (2% CHX gel), and N-acetylcysteine (NAC) on the levels of RvE1 and RvD2 in periapical tissues. Methodology: Thirty-six single-rooted teeth with primary endodontic infections and apical periodontitis were selected and randomly divided into three groups according to the medication: [Ca(OH)2] + saline solution (SSL) [Ca(OH)2 + SSL group] (n = 12), Ca(OH)2 + 2% chlorhexidine gel [Ca(OH)2 + 2% CHX gel group] (n = 12) and NAC [NAC group] (n = 12). Samples were collected from the periapical interstitial fluid at two different sampling times: before (S1) and after 14 days of intracanal medications (S2). Resolvins were measured using the enzyme-linked immunosorbent assay. Data were analysed using paired t-test, Wilcoxon test and Kruskal–Wallis test, followed by Dunn’s post hoc test; all statistical tests were performed at a significance level of 5%. Results: RvE1 and RvD2 were detected in 100% of the samples (36/36) at S1 and S2. Ca(OH)2 medication did not increase the levels of RvE1 or RvD2 (both P > 0.05); however, NAC significantly increased the levels of RvE1 and RvD2 after 14 days of treatment (P

Introduction Numerous previously undocumented factors may influence the healing of apical periodontitis (AP). The aim of this cohort study was to analyze the association between statin medication intake during the follow-up period and healing of AP. Methods Patients who self-reported being on statins during nonsurgical root canal treatment or retreatment and patients who reported never taking statins were included. All patients who received treatment on a tooth with periapical radiolucency in the postgraduate endodontics clinic at the University of Maryland School of Dentistry (2011–2014) were invited for follow-up 2 to 5 years after treatment. Healing was determined using the periapical index (PAI). Two calibrated endodontists assessed outcomes blinded to the statin intake. The association of statin intake and healing of endodontic treatment (ie, healed [PAI 1–2]/not healed [PAI 3–5]) was analyzed using the Fisher exact test. Logistic regression analysis was used to explore the association between statin intake and treatment outcome, controlling for the following confounding variables: diabetes mellitus, cardiovascular disease, and smoking, with confidence intervals set at 95%. Results A total of 60 cases were included in the final analysis, including 30 patients taking statins and 30 patients not taking statins as the control. The Fisher exact test showed significantly higher healing at the 2-year or greater follow-up in patients taking statins compared with controls (93.0% vs 70%; Fisher exact test, P = .02). Conclusions The results of this study show a significant association between long-term statin intake and healing of AP after nonsurgical root canal treatment.

Herein, we investigated a biointeractive tooth sealing material consisted of dimethylaminohexadecyl methacrylate (DMAHDM) and amorphous calcium phosphate nanoparticles (NACPs) to address the above issues simultaneously. Of note, 5% DMAHDM was incorporated into the resin blend, and 20% NACP was added to inorganic filler content of dental formulations intended as dental sealants. The sealing materials were used to seal human extracted teeth. The sealed teeth were subjected to an early childhood caries (ECC) key pathogen (Candida albicans and Streptococcus mutans) biofilm model using a dynamic caries tooth model (CDC reactor). The biofilm growth over the sealed teeth was assessed via colony-forming unit counting metabolic activity assays. The enamel surface hardness loss, degree of conversion, shear bond strength (SBS), and cytotoxicity were also investigated. Formulations having DMAHDM displayed antibacterial efficiency of 2.8-3.5 and 1.4-4.0 log inhibition for Streptococcus mutans and Candida albicans, respectively. Furthermore, the metabolic activity was reduced on the top of the sealed tooth with the biointeractive sealing materials (p < .05). The degree of conversion values was acceptable. The enamel surface hardness loss decreases (36 ± 9.8%) when in contact with the biointeractive tooth sealing material. The SBS of the combined formulation (5% DMAHDM + 20% NACP) was lower than commercial sealant but similar to experimental control. The investigated sealing material holds valuable dual antibacterial and antifungal activities associated with a reduced mineral loss against the cariogenic challenge promoted by ECC key pathogens.

Composite restorations are increasingly popular, but recurrent caries is a main reason for composite restoration failures. The objectives of this study were to investigate a dual strategy of combining rnc gene-deletion for Streptococcus mutans (S. mutans) with antibacterial dimethylaminohexadecyl methacrylate (DMAHDM) composite, and determine the effects of rnc gene-deletion alone, DMAHDM composite alone, and rnc-deletion plus DMAHDM composite, on biofilm growth and lactic acid production.Parent S. mutans (UA159, ATCC 700610) and rnc-deleted S. mutans were used. DMAHDM was incorporated into a composite at mass fractions of 0%, 1.5%, and 3%. Gene expressions for biofilm formation and drug resistance were analyzed using quantitative real-time polymerase chain reaction (qRT-PCR). Biofilms were grown on composite surfaces for 2 days. Live/dead, biomass, polysaccharide, metabolic activity (MTT), colony-forming units (CFU) and lactic acid production of biofilms were evaluated.Compared to the parent S. mutans, the rnc-deletion technique yielded significantly less biofilm biomass, polysaccharides, metabolic activity, CFU, and lactic acid for biofilms grown on control composite (p 0.05). With no gene modification, the biofilm CFU was decreased by 5-6 logs at 3% DMAHDM, when compared to control composite group. The dual strategy of combining rnc-deletion with 3% DMAHDM composite achieved the strongest biofilm-inhibition, with the greatest reduction in CFU by 8 logs. The combination of rnc-deletion with 3% DMAHDM composite decreased the biofilm lactic acid production by 95% (p 0.05).The dual strategy of rnc-deletion plus DMAHDM composite produced synergistic effects and achieved the strongest biofilm-inhibition. This method has great potential to inhibit dental caries and is promising to reduce secondary caries and protect tooth structures.

This study was carried out to investigate the microbial profile and endotoxin levels of endodontic-periodontal lesions of periodontal origin. Periodontal and endodontic samples were taken from periodontal pockets and necrotic root canals of 10 teeth with endodontic-periodontal lesions. Evidencing of 40 different bacterial species were determined in each endodontic and periodontal sample using the checkerboard DNA-DNA hybridization method and Kinetic chromogenic LAL assay was used for quantification of endotoxins. Fisher’s exact test correlated the bacterial species with the endodontic or periodontal microbiota. The endotoxin levels (EU/mL) found in samples of the root canal and periodontal pocket were compared by the Wilcoxon test (p

The present study aimed to compare the effectiveness of QMiX and 17% EDTA associated to passive ultrasonic irrigation (PUI) or manual agitation (MA) on the reduction of E. faecalis, E. coli and LPS from root canals. Forty single rooted human teeth were randomly divided into four groups (n=10), according to the final irrigation protocol: EDTA+MA, QMiX+MA, EDTA+PUI, QMiX+PUI. Sample collections were obtained from the root canal content immediately before preparation (baseline-S1), after instrumentation (S2), after final irrigation protocol (S3) and 7 days after instrumentation and final irrigation (S4). The antimicrobial effectivity and on endotoxin content were analyzed by culture procedure (CFU/mL) and LAL assay (EU/mL), respectively. The results were statistically analyzed by Kruskal-Wallis and Friedman test (α=5%). QMiX+MA and QMiX+PUI reduced 100% of E. coli and E. faecalis bacteria and also prevented E. faecalisregrowth at S4. EDTA significantly reduced E. coli, but it was not effective in reducing E. faecalis. All protocols reduced EU/mL when compared to S1, however at S4 there was a significant reduction of EU/mL only in the QMiX+MA and QMiX+PUI groups in relation to S3 and S2, respectively. Final irrigation with QMiX associated with MA or PUI had superior antibacterial efficacy compared to EDTA, eliminating 100% of E. coli and E. faecalis strains. In addition, QMiX+PUI reduced 97.61% of the initial content of LPS. Resumo O presente estudo objetivou comparar a eficácia do QMiX e do EDTA 17% associado à irrigação ultrassônica passiva (PUI) ou agitação manual (MA) na redução de E. faecalis, E. coli e LPS de canais radiculares. Quarenta dentes humanos unirradiculares foram divididos aleatoriamente em quatro grupos (n = 10), de acordo com o protocolo final de irrigação: EDTA+MA, QMiX+MA, EDTA+PUI, QMiX+PUI. Coletas das amostras foram obtidas a partir do conteúdo do canal radicular imediatamente antes do preparo (inicial-S1), após a instrumentação (S2), após o protocolo final de irrigação (S3) e 7 dias após a instrumentação e irrigação final (S4). A eficácia antimicrobiana e o conteúdo de endotoxina foram analisados por procedimento de cultura (UFC/mL) e ensaio LAL (EU/mL), respectivamente. Os resultados foram analisados estatisticamente pelo teste de Kruskal-Wallis e Friedman (α = 5%). QMiX+MA e QMiX+PUI reduziram 100% das bactérias E. coli e E. faecalis e também preveniram a recolonização de E. faecalis em S4. O EDTA reduziu significativamente E. coli, mas não foi eficaz na redução de E. faecalis. Todos os protocolos reduziram EU/mL quando comparados com S1, no entanto, no S4 houve uma redução significativa de EU/mL apenas nos grupos QMiX+MA e QMiX+PUI em relação a S3 e S2, respectivamente. A irrigação final com QMiX associada a MA ou PUI apresentou eficácia antibacteriana superior em relação ao EDTA, eliminando 100% das cepas de E. coli e E. faecalis. Além disso, QMiX+PUI reduziu 97,61% do conteúdo inicial de LPS.

Made available in DSpace on 2020-12-12T02:32:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01 Dens invaginatus is a malformation affecting mainly the superior lateral incisors. It is defined as an infolding of the crown hard tissues, including the enamel and dentin, and can extend up to the root apex. Root canal treatment of this abnormality is considered difficult due to the complex anatomy presented by these teeth. This case series presents nonsurgical endodontic treatment in two cases of dens invaginatus (type II and III) in maxillary lateral incisors. This nonsurgical or conventional endodontic treatment results in healing of the periapical lesions associated with both cases, with no need for extra intervention e.g. surgical or invasive management. The manual instrumentation associated with sodium hypochlorite and calcium hydroxide were able to completely heal the lesions. Radiographic exams were carried out to control and asses the healing. Nonsurgical treatment was successful in both cases with adequate repair after a 6-year follow-up with radiographic and tomographic assessments. Department of Restorative Dentistry Endodontic Division Institute of Science and Technology São Paulo State University (UNESP) Department of Science and Technology Applied to Dentistry Institute of Science and Technology São Paulo State University (UNESP) Department of Restorative Dentistry Operative Dentistry Division Institute of Science and Technology São Paulo State University (UNESP) Department of Endodontics Prosthodontics and Operative Dentistry School of Dentistry University of Maryland Baltimore Department of Restorative Dentistry Endodontic Division Institute of Science and Technology São Paulo State University (UNESP) Department of Science and Technology Applied to Dentistry Institute of Science and Technology São Paulo State University (UNESP) Department of Restorative Dentistry Operative Dentistry Division Institute of Science and Technology São Paulo State University (UNESP)

Made available in DSpace on 2019-10-06T17:19:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01. Added 1 bitstream(s) on 2021-07-15T15:23:58Z : No. of bitstreams: 1 S1806-83242019000100229.pdf: 292833 bytes, checksum: 5b9037955a0da1a8c64db0b60a9f38b5 (MD5) This clinical study compared the effectiveness of two rotary systems: HyFlex CM (Coltene-Whaledent, Altstetten, Switzerland) and ProTaper Next (Dentsply Sirona, Ballaigues, Switzerland) on the removal of cultivable bacteria and endotoxins from primarily infected root canals. This study was designed as a randomized single-blinded, 2-arm, clinical trial. Twenty-four primarily infected root canals were selected and randomly divided into 2 groups: HyFlex CM (n = 12); and ProTaper Next (n = 12). Samples were collected before and after the biomechanical preparation and inoculated in specific flasks. Irrigation was performed using 2.5% sodium hypochlorite. A kinetic turbidimetric lysate assay of limulus amoebocytes was used to quantify endotoxins. Microbiological culture technique was used to determine the count of bacterial colony forming units (CFU/mL). Data collected were statistically analyzed using SigmaPlot 12.0 for Windows. The Two-Way ANOVA statistical test was performed and the level of significance was 5%. In the samples before the biomechanical preparation, cultivable bacteria and endotoxins were evidenced in 100% of the cases. The culture analysis revealed that there was no statistically significant difference in the bacterial reduction between the two instrumentation systems. Endotoxins were present in 100% of the canals after instrumentation and there was no statistical difference between the two systems in endotoxin reduction. Thus, it was concluded that both instrumentation systems were effective in reducing root canal bacteria and endotoxins with primary endodontic infection and that there was no statistical difference between them. However, no system was able to eliminate 100% of the bacteria and their by-products. Endodontic Division School of Dentistry Universidade Estadual Paulista - Unesp SP Baltimore School of Dentistry, University of Maryland, Baltimore, MD, USA Endodontic Division School of Dentistry Universidade Estadual Paulista - Unesp SP

The persistence of microorganisms in the root canal system is one of the leading causes of root canal treatment failure. Root canal anatomy is complex, and it is often a challenge to obtain optimal disinfection. Biofilms of putative pathogens hidden inside dentin tubules and other root canal ramifications may limit current disinfection protocols. The search for additional disinfection of the root canal has been intensely carried out over the last twenty years. Antimicrobial photodynamic therapy (aPDT) is an adjunctive, conservative, non-selective bacterial kill approach. aPDT has been used to improve root canals disinfection without inducing bacterial resistance. This review focuses on the up-to-date aPDT performance and upcoming promising strategies for disinfection of the root canal system. First, we summarized the barriers encountered by photosensitizer (PS) and light delivery applied to root canal disinfection. Second, we compile the most updated clinical literature. A systematic search for scientific articles was conducted in PubMed, MEDLINE, SCOPUS, and EMBASE to screen the related in vivo studies about this theme. Third, we summarized and critically analyzed the current developments to overcome the aPDT limitations, and we revealed upcoming perspectives in this scoping literature review. We present a timely and opportune review article focusing on the significant potential of aPDT in endodontic disinfection. aPDT offers multiple capabilities that may be considered toward the root canal system’s disinfection with future outlooks in nanosized-platforms’ design and performance.

Made available in DSpace on 2018-12-11T17:13:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-09-01 Aim To evaluate the effectiveness of supplemental photodynamic therapy (PDT) in optimizing the removal of bacteria and endotoxins from primarily infected root canals after one-visit and two-visit treatments. Methodology Twenty-four primarily infected root canals with apical periodontitis were selected and randomly divided into one-visit (n = 12) and two-visit treatment groups (n = 12). Chemo-mechanical preparation (CMP) was performed by using the single-file reciprocating technique + 2.5% NaOCL and a final rinse with 17% EDTA. The photosensitizer agent (methylene blue 0.1 mg/mL) was applied to root canals for 60 s before application of laser with a potency of 60 mW and energy density of 129 J/cm2 for 120 s after CMP in the one-visit treatment and after 14-day inter-appointment medication with Ca(OH)2 + Saline solution (SSL) in the two-visit treatment. Samples were collected before and after root canal procedures. Endotoxins were quantified by chromogenic limulus amebocyte lysate assay. Culture techniques were used to determine bacterial colony-forming unit counts. Results Bacteria and endotoxins were detected in 100% of the initial samples, with median values of 1.97 × 105 CFU/mL and 24.983 EU/mL, respectively. The CMP using single-file reciprocating technique was effective in the reduction of bacteria and endotoxins (All, p 0.05). In the two-visit group, after 14 days of inter-appointment medication with Ca(OH)2, a significant reduction in the median levels of endotoxins was found in comparison to CMP alone (from 1.041 to 0.094 EU/mL) (p 0.05). Conclusions The photodynamic therapy optimized the disinfection of bacteria from root canals in one-visit but not for two visit treatment modality with the accomplishment of calcium hydroxide medication. Despite the type of treatment, the supplemental PDT was not effective against endotoxins. Department of Restorative Dentistry Endodontic Division São José dos Campos Dental School State University of São Paulo UNESP University of Maryland-Baltimore Department Oral Sciences & Therapeutics School of Dentistry, 21201 Baltimore Department of Restorative Dentistry Endodontic Division São José dos Campos Dental School State University of São Paulo UNESP

Objective: This study sought to investigate the prevalence of eight oral Treponemas (Treponema denticola, T. amylovorum, T. maltophilum, T. medium, T. pectinovorum, T. socranskii, T. vicentii and T. lecithinolyticum) in teeth with endodontic treatment failure and periapical lesion. Methods: Samples were taken from 40 root canals presenting endodontic failure and periapical lesion. DNA extraction was performed and Nested-PCR technique was used for the detection of Treponema species using specific primers. Results: Treponemas was detected in 56.5% of the samples analyzed (22/39). Individual root canals yielded a maximum of 6 target Treponema species. T. denticola (30.8%) and T. maltophilum (30.8%) were the most frequently detected species followed by T. medium (20.5%), T. socranskii (20.5%), T. pectinovorum (17.9%) and T. vicentii (17.9%). Positive association was verified between T. denticola and T. maltophilum such as T. medium (P