Sonic Activation Research Articles

Comparative Evaluation of Modified Endodontic Sealers’ Penetration Following Sonic Activation of Irrigants: A Scanning Electron Microscope Study

Introduction: When sealer is adapted well to the root canal wall, there is less tendency for microleakage and strength of root canal is enhanced. Therefore, it is important for the sealer to possess good tubular penetration depth and adaptation to dentinal walls. Aim: To compare the effects of sonic activation of 5.25% Sodium Hypochlorite (NaOCl) and incorporation of Zinc Oxide (ZnO) nanoparticles in AH Plus sealer on tubular sealer penetration. Materials and Methods: Forty extracted human mandibular premolars with a single root canal were used for this invitro study from October 2019 to January 2020. All teeth were prepared upto F3 with Pro Taper Universal rotary system. Teeth were randomly divided into four groups of 10 teeth each. Group I (control) included teeth obturated using AH plus sealer, Group II: teeth obturated using AH plus sealer incorporated with ZnO nanoparticles, Group III: teeth prepared along with sonic activation of the irrigant followed by obturation using AH plus sealer and Group IV: teeth prepared along with sonic activation of the irrigants followed by obturation with AH plus sealer incorporated with ZnO nanoparticles. Irrigation was achieved with 5.25% sodium hypochlorite. The canals were dried and obturated using respective sealers and single gutta percha cones. After storage at 37°C and 100% humidity, the roots were split into two halves and sealer penetration in the dentinal tubules was examined by using scanning electron microscope. The values obtained were statistically analysed using One-way Analysis of Variance (ANOVA) with significant p-value less than 0.05. Results: In all the groups, sealer penetrated into the dentinal tubules. There was enhanced tubular sealer penetration (289.57±59.43 μm) after sonic activation of the irrigant (group 3) followed by that on addition of ZnO nanoparticles to the sealers (group 2) (278.21±71.24 μm) and the least was seen in the control group (group 1) (211.5±66.33 μm). The combined effect of both i.e., use of sonic activation of irrigant followed by obturation using modified sealer with gutta percha (group 4) (318.64±88.27 μm) showed greatest tubular sealer penetration depth. Conclusion: Incorporation of nanoparticles aids in improving sealer penetration which is further enhanced in case of sonic activation during irrigation.

Kitosan ve EDTA Solüsyonlarının Sonik ve Ultrasonik Sistemler ile Aktive Edilmesinin Dentin Mikrosertliğine Olan Etkisi

Objective: The aim of this in vitro study is to assess the effect of activation of EDTA and chitosan by different irrigation activation systems on the microhardness of root canal dentin. Material and Methods: A total of 60 single-rooted extracted mandibular premolars were prepared and randomly distributed into two groups (n=30) based on the final irrigant: Group 1, 0.2% chitosan; Group 2, 17% EDTA. Then, specimens of both groups were randomly divided into three subgroups (n=10) based on the irrigant activation; Subgroup A (Sonic), Subgroup B (Ultrasonic) and Subgroup C (Conventional irrigation, control group). The specimens (n=60) were embedded into resin blocks and sectioned horizontally 1 mm thick sections from 2,5 and 8 mm levels from the apex. All samples were used to determine the microhardness of dentin using a Vicker's microhardness tester. The data were analyzed using the three-way analysis of variance (ANOVA) and Tukey post-hoc tests to detect the effects of the independent variables (final irrigation solution, final irrigation techniques, and root canal thirds) on microhardness. Results: The three-way ANOVA indicated that chitosan exhibited a significantly lower microhardness value than EDTA (p<0.001). Also, regardless of the usage of final irrigation, both PUI and EA had significantly lower microhardness than CI (p<0.001). Conclusion: Chitosan as compared to EDTA (i), sonic (EA) and ultrasonic (PUI) final irrigation activation methods as compared to the traditional syringe method (CIS) (ii), apical and mid regions of the root as compared to its coronal region (iii), showed lower microhardness values.

Protective effects of Phlomis umbrosa extract on a monosodium iodoacetate–induced osteoarthritis model and prediction of molecular mechanisms using transcriptomics

Abstract Background Phlomis umbrosa Turczaninow root has been traditionally used to treat fractures, rheumatoid arthritis, and arthralgia. However, the effects and mechanisms of P. umbrosa on osteoarthritis (OA) remain poorly understood and a functional genomic approach has not been investigated. Aim The purpose of this study was to investigate the effects and mechanisms of P. umbrosa extract (PUE) on OA using transcriptomic analysis. Methods We performed joint diameter measurements, micro computed tomography, and histopathological analysis of monosodium iodoacetate (MIA)-induced OA rats treated with PUE (200 mg/kg) for 3 weeks. Gene expression profiling in articular cartilage tissue was then performed using RNA sequencing (RNA-seq) followed by signaling pathway analysis of regulatory genes. Results PUE treatment improved OA based on decreased joint diameter, increased joint morphological parameters, and histopathological features. Many genes involved in multiple signal transduction pathway and collagen activation in OA were differentially regulated by PUE. These included genes related to Wnt/β-catenin, OA pathway, and sonic hedgehog signaling activity. Furthermore, PUE treatment downregulated cartilage damage factors (MMP-9, MMP-13, ADAMTs4, and ADMATs5) and upregulated chondrogenesis (COL2A1 and SOX-9) by regulating the transcription factors SOX-9, Ctnnb1, and Epas1. Conclusion Based on the results of gene expression profiling, this study highlighted the molecular mechanisms underlying the effects of PUE in MIA-induced OA rats. The findings provide novel insight into the mechanisms by which PUE treatment-induced gene expression changes may influence OA disease progression. Taken together, the results suggest that PUE may be used as a source of therapeutic agents for OA.

Kavite tasarımının kalsiyum hidroksitin kök kanal düzensizliklerinden uzaklaştırılmasına etkisi

Objective: Conservative endodontic cavity (CEC) design has recently developed to maintain the stability of tooth and provided an alternative to traditional endodontic cavity (TEC) design. The purpose of this study was to assess the influence of cavity design on calcium hydroxide (Ca(OH)2) removal from artificial grooves in the coronal and apical parts of root canals. Materials and Methods: Fourty extracted human mandibular premolars with single canals were randomly assigned to CEC or TEC groups (n=20). Following cavity preparation, the root canals were instrumented and then, each tooth was sectioned longitudinally. Two standardized grooves were prepared in the coronal and apical parts of 1 root half. Ca(OH)2 was placed into the grooves and the root halves reassembled. After 1 week, each root canal was enlarged to a final apical size of 40 and irrigation was performed with the sonic activation of 2.5% sodium hypochlorite and 17% ethylenediaminetetraacetic acid solutions. The remaining Ca(OH)2 in the grooves was evaluated using a stereomicroscope and the images were scored by 2 examiners. Data were analyzed using the Mann-Whitney U and Wilcoxon tests. Ca(OH)2 remnants were found in both groups. Results: There was no significant difference between the CEC and TEC groups in terms of Ca(OH)2 removal efficacy (p&amp;gt;0.05). The grooves in the coronal and apical parts of the roots presented similar amount of Ca(OH)2 remnantsin both groups (p&amp;gt;0.05). Conclusion: The cavity design had no effect on the removal of Ca(OH)2 from root canal irregularities.

Multiple steps characterise ventricular layer attrition to form the ependymal cell lining of the adult mouse spinal cord central canal.

The ventricular layer of the spinal cord is remodelled during embryonic development and ultimately forms the ependymal cell lining of the adult central canal, which retains neural stem cell potential. This anatomical transformation involves the process of dorsal collapse; however, accompanying changes in tissue organisation and cell behaviour as well as the precise origin of cells contributing to the central canal are not well understood. Here, we describe sequential localised cell rearrangements which accompany the gradual attrition of the spinal cord ventricular layer during development. This includes local breakdown of the pseudostratified organisation of the dorsal ventricular layer prefiguring dorsal collapse and evidence for a new phenomenon, ventral dissociation, during which the ventral‐most floor plate cells separate from a subset that are retained around the central canal. Using cell proliferation markers and cell‐cycle reporter mice, we further show that following dorsal collapse, ventricular layer attrition involves an overall reduction in cell proliferation, characterised by an intriguing increase in the percentage of cells in G1/S. In contrast, programmed cell death does not contribute to ventricular layer remodelling. By analysing transcript and protein expression patterns associated with key signalling pathways, we provide evidence for a gradual decline in ventral sonic hedgehog activity and an accompanying ventral expansion of initial dorsal bone morphogenetic protein signalling, which comes to dominate the forming the central canal lining. This study identifies multiple steps that may contribute to spinal cord ventricular layer attrition and adds to increasing evidence for the heterogeneous origin of the spinal cord ependymal cell population, which includes cells from the floor plate and the roof plate as well as ventral progenitor domains.

Integrated Multi-Omics Characterization of Neurofibromatosis Type 1 Related Peripheral Nerve Sheath Tumors Identifies Two Distinct Malignant Peripheral Nerve Sheath Tumors Subtypes with Sonic Hedgehog or WNT Pathway Activation

Abstract INTRODUCTION Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive Schwann-cell derived sarcomas and the leading cause of mortality in neurofibromatosis Type 1. In many cases, MPNSTs develop through malignant transformation of an underlying neurofibroma (NF). The genomic alterations and molecular pathways driving malignant transformation is not well understood. In this study, we leverage multi-platform genomic and epigenomic profiling of human NFs and MPNSTs to identify targetable molecular pathways that lead to malignant transformation. METHODS Fresh-frozen tumor (N = 108; 19 MPNSTs, 18 premalignant NFs, 37 benign peripheral nerve NFs, and 34 cutaneous NFs) and matched-controls were allocated for NGS platforms including methylation-profiling, RNA, whole exome and ChIP sequencing. In addition, functional validation of identified pathways was performed using CRISPR/cas9 knockout of relevant sonic hedgehog (SHH) and WNT pathway genes in immortalized neurofibroma cell lines. RESULTS Unsupervised consensus clustering of peripheral nerve tumors identified 4 distinct methylation subgroups, with MPNSTs clustering in either Methyl_Grp-2B or Methyl_Grp-3. Transcriptomic analysis of the MPNSTs, identified SHH pathway activation in Methyl_Grp-3 MPNSTs (NES = 1.9952, P &lt; .0001, FDR &lt; 0.001) and WNT pathway activation in Methyl_Grp-2B MPNSTs (NES = 1.7630, P &lt; .0001, FDR = 0.0058). Single sample gene set enrichment analysis demonstrates that there is a strong negative correlation between SHH and WNT pathway activation in MPNSTs (r = −0.78, P = .007). Methyl_Gr-3 MPNSTs harbor more PTCH1 copy number loss (62.5% vs 0%, P &lt; .05) and PTCH1 promoter hypermethylation (mean beta value: 0.2899 vs. 0.06119, P &lt; .05). PTCH1 knockout in immortalized neurofibroma cell lines increased expression of SHH pathway target genes (GLI1, GLI2, and SMO), and increased cellular proliferation and invasiveness. CONCLUSION We found that MPNSTs can be classified into two molecular subgroups driven by SHH or WNT pathway activation. Furthermore, PTCH1 loss is one mechanism that mediates SHH pathway activation. These results suggest a targeted approach should be taken for treating MPNSTs, and SHH and WNT pathway inhibition may be promising avenue for therapeutic development.

Perbedaan Kebersihan Sepertiga Apikal Saluran Akar dari Smear Layer Menggunakan Sistem Aktivasi Ultrasonik dan Sonik

Irrigant activation is important for successful endodontic treatment. There are some of activation technique those are manual irrigation with needle irrigation and mechanics irrigation with sonic, and ultrasonic activation. The aim of this study was to compare the effectiveness between sonic and ultrasonic activation technique as irrigation activation for smear layer removal in apical third of the root canal. Fifteen mandibular premolars were used. NaOCl 2,5% and EDTA 17% was used as an irrigant. Sample were divided into 3 equal group (n=5) according to the final activation technique: group I as a needle irrigation II as a ultrasonic activation, group III sonic activation. Root canals were split longitudinnaly and subjected to scanning electron microscope with 2000x magnification. Data were evaluated using statistics kruskall wallis and mann whitney. The result of this study shows there were statistically significant differences in staistics Mann Whitney on group III were more clean than group II p &lt; 0,05. Sonic technique more effective in removal of smear layer in apical third of the root canal than ultrasonic activation technicque. Important to noted the variant of irrigant and activation.

Driver mutations in USP8 wild-type Cushing's disease.

BackgroundMedical treatment in Cushing’s disease (CD) is limited due to poor understanding of its pathogenesis. Pathogenic variants of ubiquitin specific peptidase 8 (USP8) have been confirmed as causative in around half of corticotroph tumors. We aimed to further characterize the molecular landscape of those CD tumors lacking USP8 mutations in a large cohort of patients.MethodsExome sequencing was performed on 18 paired tumor–blood samples with wild-type USP8 status. Candidate gene variants were screened by Sanger sequencing in 175 additional samples. The most frequent variant was characterized by further functional in vitro assays.ResultsRecurrent somatic hotspot mutations in another deubiquitinase, USP48, were found in 10.3% of analyzed samples. Several possibly damaging variants were found in TP53 in 6 of 18 samples. USP48 variants were associated with smaller tumors and trended toward higher frequency in female patients. They also changed the structural conformation of USP48 and increased its catalytic activity toward its physiological substrates histone 2A and zinc finger protein Gli1, as well as enhanced the stimulatory effect of corticotropin releasing hormone (CRH) on pro-opiomelanocortin production and adrenocorticotropic hormone secretion.ConclusionsUSP48 pathogenic variants are relatively frequent in USP8 wild-type tumors and enhance CRH-induced hormone production in a manner coherent with sonic hedgehog activation. In addition, TP53 pathogenic variants may be more frequent in larger CD tumors than previously reported.

Trimming of Absorbable Plates and Screws through Smoothing by Multiple Sonic Activation Procedures Can Increase Local Tissue Reactions in Children with Cranial Fixations

Objective: The aim of this paper was to investigate the local reactions due to the melting of absorbable plates and screws after trimming through smoothing by multiple sonic activation procedures (MSAP). Background: Drilling or smoothing by MSAP is performed for the trimming of the absorbable plates and screws for cranial fixation in children. Compared to drilling, smoothing by MSAP is suspected to more commonly cause local tissue reactions; thus, the issue was examined herein. Methods: For 90 children with smoothing by MSAP and 83 children with drilling procedures who underwent cranial fixation using absorbable plates and screws, the type, time of onset, and incidence of the local reactions were investigated. Results: Swelling was the most common reaction, followed by inflammatory reactions with itching, heating, skin-penetrating drainage, and pus formation. The mean time of onset of the local reaction was 10.0 ± 2.3 months after surgery. Local reactions occurred in 30% of the children in the group with smoothing by MSAP, and in 7.2% of the children in the group with drilling, showing a statistically significant difference between the two groups (p < 0.001). Conclusion: It was concluded that drilling rather than smoothing by MSAP to change the shapes of the absorbable plates and screws in cranial fixation can reduce the local reactions.

Evaluation of two shaping systems and two sonic irrigation devices in removing root canal filling material from distal roots of mandibular molars assessed by micro CT

To compare two preparation systems and two sonic irrigation devices during the removal of root filling material from oval distal canals of extracted mandibular molars. The distal canals in 40 extracted mandibular molars were shaped using the ProTaper Next system (Dentslpy Sirona, Ballaigues, Switzerland), filled with Gutta Percha X2 (Dentsply Sirona), along with AH Plus sealer (Dentsply De Trey, Konstanz, Germany) and randomly divided into two groups (n=20) according to volume of initial filling, preparation diameter and working length. One group was retreated using the Reciproc system (VDW, Munich, Germany), and the other using the 2Shape system (Micro-Mega, Besançon, France). A micro-CT scan was taken after the initial root filling and after retreatment to evaluate the volume of filling material remnants. The teeth were divided into four groups to test the supplementary effect of two sonic irrigation devices on removing filling material: Eddy (VDW) and MM1500 (Micro-Mega). In the first and second groups, 2Shape was followed subsequently by MM1500 and Eddy; in the third and fourth groups, Reciproc was followed by MM1500 and Eddy. A third micro-CT was taken to compare the remaining root filling material in all groups. Wilcoxon's signed rank tests, Mann-Whitney and Kruskal-Wallis tests were used for statistical analysis. No significant difference was found for the volume of filling material removed between the Reciproc and 2Shape in the entire canal (P=0.355). The volume dropped significantly from its initial value after removing the bulk of the root filling by 95.8% (from 4.71 to 0.22mm3 ) with the 2Shape (P<0.001) and by 94.0% (from 5.05 to 0.33mm3 ) with the Reciproc (P<0.001). Sonic activation significantly decreased the residual volume of filling material remnants by 3.21% (P=0.013) in the first group, 1.38% (P=0.012) in the second group, 1.83% (P=0.008) in the third group and 1.83% (P=0.012) in the fourth group. At the end, the percentage of residual material was not significantly different among the groups in the entire canal (P=0.163). In the distal oval canals of extracted mandibular molar teeth, there was no significant difference between the 2Shape and Reciproc systems in removing gutta-percha/sealer. Sonic activation with MM1500 and Eddy significantly improved filling material removal.

Comparison of bacterial removal from dentinal tubules with different irrigant agitation techniques: An in vitro study

AimThis investigation was conducted to assess the ability of various irrigant agitation devices to eradicate Enterococcus faecalis from the dentinal tubules of extracted teeth. MethodologyFifty roots of extracted human teeth were instrumented to size 30 k with a 0.04 taper. The roots were autoclaved and then injected with E. faecalis. The canals were assigned to one of four intervention groups and disinfected using (A) standard needle irrigation, (B) EndoUltra® Ultrasonic Activator, (C) the EndoActivator system, or (D) EDDY sonic activation and to two control groups that were (E) treated with saline and (F) not inoculated with any bacteria. The roots were split in half, dyed with a LIVE/DEAD Back Light Bacterial Viability Kit, and then scanned with a confocal laser scanning microscope (CLSM) to identify live/dead bacteria in the dentinal tubules. ResultsCLSM images revealed differences among the groups. Both the EndoUltra® Ultrasonic Activator group and the EDDY group had a combination of dead and live bacteria, while the EndoActivator group had mostly dead bacteria, in contrast to single needle irrigation which had mostly live bacteria. Activation of the irrigating solution resulted in more dead bacteria than standard needle irrigation at the coronal, middle, and apical parts of the roots. Overall, the EndoActivator system was superior to all other techniques in reducing live bacteria within the root canal. ConclusionActivation of sodium hypochlorite with sonic and ultrasonic systems dramatically reduced live bacteria contamination in the dentinal tubules of infected root canals.

Novel Activated Microbubbles-based Strategy to Coat Nanoparticles on Root Canal Dentin: Fluid Dynamical Characterization

IntroductionActivated microbubbles (MBs) have the potential to deliver nanoparticles in complex microspaces such as root canals. The objective of the study is to determine the fluid dynamical parameters associated with ultrasonic, sonic, and manual activation of MBs in simulated root canals and to assess the effectiveness of surface coating formed by delivering chitosan nanoparticles using activated MBs within root canals in extracted teeth. MethodsIn stage 1, polydimethylsiloxane models were fabricated to determine the physical effects of MBs agitated manually (MM), sonically (MS), and ultrasonically (MU). Spherical tracer particles were used to visualize and record the fluid motion using an inverted microscope linked to a high-speed camera. The velocity, wall stress, and penetration depth were analyzed at regions of interest. In stage 2, 35 extracted human incisors were divided into 7 groups to evaluate the effectiveness of chitosan nanoparticle delivery using activated MBs (MM, MS, and MU groups). Field emission scanning electron microscopy and energy-dispersive X-rays were used to characterize the nanoparticle coating on root canal dentin and the degree of dentinal tubule occlusion. ResultsIn stage 1, velocity, wall stress, and penetration depth increased significantly in the MB groups compared with the control (P < .01). In stage 2, 70% of the dentin surface was coated, and 65% of the dentinal tubule was occluded with nanoparticle-based coating in the MM, MU, and water ultrasonic groups. Element analysis displayed the presence of dentin smear on the root canal surface for the MU and water ultrasonic groups. ConclusionsActivated MBs enhanced fluid dynamical parameters when compared with water in simulated root canal models. Manual activation of MBs resulted in uniform and significant nanoparticle-based surface coating and tubule blockage in root canal dentin without dentin smear formation.

Penetration depth of irrigants into root dentine after sonic, ultrasonic and photoacoustic activation.

To compare penetration depths of endodontic irrigants into the dentinal tubules of extracted teeth when using several activation methods. The root canals of 90 extracted human teeth were prepared to size 40, .06 taper. The straight and round-shaped root canals were distributed randomly into six groups, and final irrigation was performed with EDTA and sodium hypochlorite as follows: (I) manual dynamic activation, (II) Ultrasonic, (III) Sonic, (IV) PIPS (photon-induced photoacoustic streaming, (V) SWEEPS (shock-wave enhanced emission photoacoustic streaming) and (0) control without final irrigation or activation. Subsequently, methylene blue was inserted into the canals and activated according to the groups (I-V). Teeth were sectioned horizontally, imaged under a light microscope, and dye penetration depths were measured in six sections per tooth and 24 points on a virtual clock-face per section. Data were analysed statistically by nonparametric tests for whole teeth and separately for coronal, middle and apical thirds. Penetration of dye into the dentinal tubules was lowest for the controls. Median penetration depths amounted to 700-900μm for groups I-V with differences in the apical thirds between group I and the other test groups. Minimum penetration depths were significantly greater for PIPS in the apical thirds (P≤0.046). Greater penetration depths occurred in the apical thirds for ultrasonic, sonic and laser-induced activation compared to manual dynamic activation. PIPS was associated with deeper penetration of irrigants. The novel SWEEPS mode did not increase irrigant penetration.

Effectiveness of different activated irrigation techniques on debris and smear layer removal from curved root canals: a SEM evaluation.

This study evaluates the effectiveness of different activated irrigation techniques on removal of debris and smear layer from curved root canals. Ninety mandibular molars with a root canal curvature between 20 and 40 degrees were assigned to 4 groups (n=20): syringe irrigation (SI), passive ultrasonic activation (PUI), sonic activation with EDDY (ED) or EndoActivator (EA) and a control group. Mesiobuccal root canals were prepared to size 40, 0.04 and irrigated with NaOCl (3%) according to the respective technique. Roots were split longitudinally and subjected to scanning electron microscopic analysis. Presence of debris and smear layer was evaluated using 5-grade scoring systems with 200× and 1000× magnification, respectively. Data were analysed with nonparametric analysis for ordinal longitudinal data (α=5%). Activation of the irrigant significantly improved smear layer removal (P<0.05). Regarding debris, only activation with EA and ED was significantly more effective than SI (P<0.05). No activation technique was able to eliminate debris and smear layer completely from curved root canals.

Effects of Endodontic Irrigants on Material and Surface Properties of Biocompatible Thermoplastics.

Passive irrigation is an efficient method for a successful endodontic treatment. During sonic activation biocompatible polymer tips are used to activate irrigants. Compared to ultrasonic activation with metallic tips, polymer tips have the advantage of a reduced risk of fracture and minimise dentine damage. Hence, two polymers, polyether ether ketones (PEEK) and polyamide (PA6), were identified for the manufacturing of novel irrigation tips. The chemical resistance against the irrigants ethylenediaminetetraacetic acid (EDTA) 20%, chlorhexidine gluconate (CHX) 2% and sodium hypochlorite (NaOCl) 5.25% was analysed. Using microindentation, the change of hardness, elasticity, surface roughness and appearance of the polymers was determined. PA6 had a high absorption of irrigant compared to PEEK. PEEK was resistant to the investigated irrigants and showed no significant alteration of surface and mechanical properties, whereas PA6 slightly increased its hardness, elastic modulus and surface roughness during long-term exposure at 37 °C. However, PA6 tips seem to be a promising disposable product due to the material’s high deformability and low manufacturing costs. Particularly with regard to structural-dynamic properties and high chemical resistance, PEEK can be considered as a material for reusable irrigation tips.

Removal of Calcium Hydroxide from Artificial Grooves in Straight Root Canals: Sonic Activation Using EDDY Versus Passive Ultrasonic Irrigation and XPendo Finisher

IntroductionThe aim of the present study was to compare sonic activation using EDDY (VDW, Munich, Germany), passive ultrasonic irrigation (PUI), and mechanical activation using the XPendo Finisher (FKG Dentaire, La Chaux-des-Fonds, Switzerland) for the removal of calcium hydroxide from artificial grooves in straight root canals. MethodsThe root canals of 90 human maxillary incisors with straight root canals were prepared using Mtwo files (VDW) up to size 40/.04, and the teeth were split longitudinally. A lateral groove in the apical or coronal part was prepared in each root half and filled with calcium hydroxide, and the root halves were reassembled. Five groups were established according to the removal techniques: group A, the XPendo Finisher; group B, EDDY; group C, PUI; group D, manual irrigation with a syringe; and group E, no irrigation (the control group). The activation procedures were performed for 30 seconds with 3 mL sodium hypochlorite 3% as the irrigant. The cleanliness of the grooves was scored under 10× magnification. The median of scoring was analyzed using the Kruskal-Wallis test (P = .05). ResultsAll activation techniques were significantly more effective in the removal of calcium hydroxide than manual irrigation (P < .05). Regarding the apical groove, EDDY and PUI were significantly more effective in the removal of calcium hydroxide than the XPendo Finisher (P < .05). No difference was found for the coronal groove (P > .05). ConclusionsEDDY and PUI were significantly more effective in the removal of calcium hydroxide than the XPendo Finisher regarding the apical region. Manual irrigation was significantly less effective than all activation techniques.

Sonic hedgehog pathway activation regulates cervical cancer stem cell characteristics during epithelial to mesenchymal transition.

Resistance to therapy and metastasis remains one of the leading causes of mortality due to cervical cancer despite advances in detection and treatment. The mechanism of epithelial to mesenchymal transition (EMT) provides conceptual explanation to the invasiveness and metastatic spread of cancer but it has not been fully understood in cervical cancer. This study aims to investigate the mechanism by which silencing of E-cadherin gene regulates EMT leading to proliferation, invasion, and chemoresistance of cervical cancer cells through the Hedgehog (Hh) signaling pathway. We developed an in vitro EMT model by the knockdown of E-cadherin expression in cervical cancer cell lines.To understand the role of developmental pathway like Hh in the progression of cervical cancer, we investigated the expression of Hh pathway mediators by array in E-cadherin low cervical cancer cells and observed upregulation of Hh pathway. This was further validated on low passage patient-derived cell lines and cervical carcinoma tissue sections from cervical cancer patients. Further, we evaluated the role of two inhibitors (cyclopamine and GANT58) of the Hh pathway on invasiveness and apoptosis in E-cadherin low cervical cancer cells. In conclusion, we observed that inhibition of Hh pathway with GANT58 along with current therapeutic procedures could be more effective in targeting drug-resistant EMT cells and bulk tumor cells in cervical cancer.

The Effectiveness of Sonic-Activated Irrigation in Reducing Intratubular Enterococcus faecalis.

The purpose of this in vitro study was to compare the effectiveness of sonic activation and syringe irrigation of 5.25% sodium hypochlorite in removing the Enterococcus faecalis (E. faecalis) biofilm. Root canals of 54 extracted human single-rooted central incisors were prepared with ProTaper S1-S2-F1-F2 and Gates Gliden burs size 1, and 2 at the working length. After sterilization, the root canals were contaminated with E. faecalis suspension and randomly assigned to three groups: G1, conventional syringe irrigation; G2, sonic agitation of NaOCl with Endo Activator system; and G3, no subjected to the mentioned irrigation techniques (negative control). Canals were sampled after the disinfection procedure. The colony forming units (CFU) count was evaluated. Samples were also visualized under fluorescent microscope to count viable bacteria. Data were statistically analyzed using the Kruskal-Wallis and one-way ANOVA followed by Tukey's test (P<0.05). There was a significant reduction in the CFU count after both irrigation techniques. There was no significant difference between two techniques (P=0.874). Using bacterial viability kit, Endo Activator displayed the least viable bacteria than the other groups (P<0.001) and control group showed the greatest one (P<0.001). In this in vitro study, the Endo Activator system was more successful in reducing intratubular viable bacteria compared with NaOCl syringe irrigation alone.

Update of the therapeutic planning of irrigation and intracanal medication in root canal treatment. A literature review.

BackgroundThe success of endodontic treatment derives from the complete elimination of microorganisms capable of causing an intraradicular or extraradicular infection. To achieve a more effective eradication of these microorganisms, endodontic instrumentation must always be implemented with abundant irrigation, which has to achieve chemical, mechanical and biological effects. The irrigators most used today are NaOCl, CHX and EDTA, released into the ducts through different techniques such as syringe, manual agitation, positive or negative apical pressure, sonic or ultrasonic activation, PIPS and PDT. The objective of this review is to update the different irrigating solutions and intracanal disinfection drugs, as well as to establish an irrigation protocol in the endodontic treatment.Material and MethodsSystematic search of scientific articles in the databases PubMed, Medline and Google Scholar, with the following keywords Endodontic, Infection, Failure, Irrigation, Retreatment and Irrigation protocol. The exclusion criteria were “case report” articles and articles with a publication date prior to 2000.Results48 articles that met the inclusion criteria were analyzed. Comparing the different articles it can be seen that the NaOCl is the “gold standard” in terms of immediate antimicrobial efficacy, followed by the CHX that has a long-term antibacterial effect. As an intra-conductive drug it is advisable to use the combination of Ca(OH)2 with CPMC.ConclusionsThe most adequate irrigation protocol consists of using 2.5% NaOCl activated with ultrasound followed by a final wash with 7% MA or 0.2% CTR combined with 2% CHX. Key words:Endodontic failure, endodontic infection, enterococcus faecalis, endodontic retreatment, irrigation, sodium hipoclorite, irrigation protocol.

Sonic hedgehog pathway activation is associated with cetuximab resistance and EPHB3 receptor induction in colorectal cancer.

A major problem of colorectal cancer (CRC) targeted therapies is relapse caused by drug resistance. In most cases of CRC, patients develop resistance to anticancer drugs. Cetuximab does not show many of the side effects of other anticancer drugs and improves the survival of patients with metastatic CRC. However, the molecular mechanism of cetuximab resistance is not fully understood.Methods: EPHB3-mediated cetuximab resistance was confirmed by in vitro western blotting, colony-forming assays, WST-1 colorimetric assay, and in vivo xenograft models (n = 7 per group). RNA-seq analysis and receptor tyrosine kinase assays were performed to identify the cetuximab resistance mechanism of EPHB3. All statistical tests were two-sided.Results: The expression of EFNB3, which upregulates the EPHB3 receptor, was shown to be increased via microarray analysis. When resistance to cetuximab was acquired, EPHB3 protein levels increased. Hedgehog signaling, cancer stemness, and epithelial-mesenchymal transition signaling proteins were also increased in the cetuximab-resistant human colon cancer cell line SW48R. Despite cells acquiring resistance to cetuximab, STAT3 was still responsive to EGF and cetuximab treatment. Moreover, inhibition of EPHB3 was associated with decreased STAT3 activity. Co-immunoprecipitation confirmed that EGFR and EPHB3 bind to each other and this binding increases upon resistance acquisition, suggesting that STAT3 is activated by the binding between EGFR and EPHB3. Protein levels of GLI-1, SOX2, and Vimentin, which are affected by STAT3, also increased. Similar results were obtained in samples from patients with CRC.Conclusion: EPHB3 expression is associated with anticancer drug resistance.