Dentinal Walls Research Articles

Outcome of revascularization therapy in traumatized immature incisors

BackgroundThe aim of this retrospective analysis was to evaluate the clinical and radiological outcome of revascularization therapy in traumatized permanent incisors to determine whether this approach could be implemented into clinical routine.MethodsA total of 16 traumatized incisors (either avulsion or severe luxation/intrusion) with open apices (> 1 mm) that underwent revascularization following a standardized protocol were analyzed with a mean follow-up of 22 months. Radiographs and clinical parameters (such as root length, pulp space, dentin wall width, apical foramen, alveolar bone loss, ankylosis/mobility, supra−/infraposition, discoloration, probing depth) were compared pre- and postoperatively and statistically analyzed.ResultsOver the follow-up period, 81.3% of the teeth survived revascularization and regained sensitivity, while 18.7% failed, as they had to be extracted due to serious root resorption. Regarding radiographic outcomes a significant difference could only be found in the decrease of apical foramina (p = 0.04). The other parameters showed no significant difference between pre- and postoperative measurements. More than half of the teeth (56.3%) developed root resorptions and 31.3% displayed signs of ankylosis and 92.9% developed discolorations during follow-up. However, 85.7% of the teeth maintained the bone level and outcomes of mobility showed a significant solidification.ConclusionsRevascularization is a promising approach for the treatment of immature incisors to regain sensitivity and to enhance apical closure and at least to maintain alveolar bone in terms of a socket preservation. Further studies have to be performed to determine ideal conditions (type of trauma, age, width of apical foramen) for a revascularization.

Dislodgement resistance and adhesive pattern of different endodontic sealers to dentine wall after artificial ageing: an in-vitro study.

To compare the dislodgement resistance and the adhesive pattern of four different endodontic sealers to root dentine walls. Ninety lower premolars were assigned to five groups (n = 18), Group 1: no sealer (control); Group 2: EndoRez (ERZ); Group 3: Sealapex (SPX); Group 4: EndoSeal MTA (ESA) and Group 5: BioRoot RCS (BRS). They were instrumented up to size 30 taper 0.06 and obturated using single cone technique with matched-taper gutta-percha cones and one of the mentioned sealers. Six teeth from each group were then randomly subjected to 100, 1000 and 10,000 thermocycles, respectively. 1mm slice of mid root region, measuring 6mm from the apical foramen was prepared and subjected to push-out test under a Universal Testing Machine. Adhesive patterns of sealers were assessed using a stereomicroscope at 20 × magnification and classified using a new system. Statistical analyses were performed using two-way ANOVA, complemented by Tukey HSD and Chi-square tests. ESA and BRS showed significantly higher (p < 0.05) push-out bond strength, followed by SPX, ERZ and lastly the control, but no significant difference was noted between ESA and BRS (p > 0.05) at 100, 1000 and 10,000 thermocycles, respectively. Both ESA and BRS exhibited a significant higher rate (p < 0.05) of Type 3 and Type 4 adhesive patterns as the thermocycles increased. ESA and BRS demonstrated higher bond strength and better adhesive pattern to root dentine wall than SPX and ERZ, especially after artificial ageing.

Marginal Adaptation And Sealing Ability Evaluation Of New Nano materials As Root End Filling Material (An Invitro Study)

Abstract Introduction: The aim of this study is evaluating marginal adaptation and sealing ability of nanoMTA and nanohydroxyapatite using bacterial microleakage method for sealing ability and scanning electron microscope (SEM) for marginal adaptation. Methods: 0ne hundred mandibular premolar extracted teeth were used in this study then divided into two subgroups fifty teeth in each according to root-end filling materials used then further subdivided into twenty-five teeth in each according to the method of assessment. Teeth were prepared using M3 Pro Gold rotary files and obturated with single cone gutta-percha and resin sealer. The apical 3mm of the roots were resected. Root-end cavity preparation were prepared and filled with nanoMTA and Nanohydroxyapatite. Group 1: bacterial microleakage assessed to NanoMTA and nanohydroxyapatite by using a model for assessment of bacterial leakage by broth changed color from red (alkaline) to yellow (acidic) as a result of acid production from bacterial growth. The samples were monitored every 24 hours for a period of 30 days. Group2: Marginal gaps between root end filling materials NanoMTA and nanohydroxyapatite with root dentin walls observed under SEM. Data were collected and statically analyzed using ANOVA tests. Results: Samples shows insignificant statistical difference between the two materials in microleakage. However, statistically significant difference at marginal gaps in nano MTA samples and nanohydroxyapatite with better results with nano MTA retrograde filling material. Conclusion: Nanohydroxyapatite might be a promising mixture to be used as a root-end filling material, as it has about the same bacterial leakage results as nanoMTA

Electrokinetic transport and distribution of antibacterial nanoparticles for endodontic disinfection.

To assess a novel, noninvasive intervention capable of mobilizing charged antibacterial nanoparticles to the apical portions of the root canal system, utilizing the principles of electrokinetics. Experiments were conducted in three stages. Stage-1: A computer model was generated to predict and visualize the electric field and current density distribution generated by the proposed intervention. Stage-2: Transport of chitosan nanoparticles (CSnp) was evaluated qualitatively using a transparent microfluidic model with fluorescent-labelled CSnp. Stage-3: An ex vivo model was utilized to study the antimicrobial efficacy of the proposed treatment against 3-week-old monospecies E.faecalis biofilms. Scanning electron microscopy (SEM) was also utilized in this stage to confirm the deposition of CSnp. The results of the computer simulations predicted an electric field and current density that reach their maxima at the apical constriction of the root canal. Correspondingly, the microfluidic experiments demonstrated rapid, controlled CSnp transport throughout the simulated root canal anatomy with subsequent distribution and deposition in the apical constriction as well as periapical regions. Infected root canals when subjected to the novel treatment method resulted in a mean bacterial reduction of 2.1 log CFU. SEM analysis revealed electrophoretic deposition of chitosan nanoparticles onto the root canal dentine walls in the apical region. The findings from this study demonstrate that the combination of cationic antibacterial nanoparticles with a low-intensity electric field results in particle transportation (electrophoresis) and deposition within the root canal. This results in a synergistic antibiofilm efficacy and has the potential to enhance root canal disinfection.

Analysis of the smear layer generated by different activation systems: an in vitro study.

To evaluate via scanning electron microscopy the amount of smear layer generated during the use of sonic and ultrasonic activation systems with standardized short-term intentional contacts with the canal walls. Seventy single-root human teeth were randomly assigned to 2 control (n= 5 each): NC (negative control), PC (positive control) and four experimental groups (n= 15 each): NC (negative control), PC (positive control), G1 (passive ultrasonic irrigation with Irrisafe), G2 (ultrasonic irrigation with EndoUltra), G3 (sonic irrigation with Endoactivator), G4 (sonic irrigation with Eddy). Samples were instrumented with ProTaper Next®. An irrigation protocol with sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA) was followed for both PC and the experimental groups. Standardized intentional contacts were made in the mesial walls during 5s at WL - 2mm in all experimental groups. Two calibrated evaluators scored the smear layer generated with an ordinal scale by scanning electron microscopy. The weighted kappa coefficient (Kw) was calculated to determine the inter-observer agreement. Post-consensus ordinal data were analyzed using the ordinal (linear) chi-square test. When the agitation file is in contact with dentine walls, Irrisafe® significantly generated the least amount of smear layer in the coronal third (p< 0.05). Both in the middle and apical third, activation with Irrisafe® also showed statistically significant better results than Eddy™ and EndoUltra®. Endoactivator® showed significant better results than EndoUltra® and Eddy™ in the apical third (p< 0.05). Irrisafe generated the least amount of smear layer in the entire canal and similar to Endoactivator in the apical third when the agitation file is in contact with dentine walls. The smear layer is generated during activation. It is common to apply irrigation protocols where after the removal of the smear layer using chelants, a final rinse and activation is carried out but there are no previous studies analyzing the possible creation of a new smear layer with this final activation.

Regenerative endodontic treatment options for immature permanent teeth: a case report with 21-month follow-up

The treatment of choice for necrotic teeth with incompletely formed roots is apexification with calcium hydroxide, which induces the formation of a hard tissue barrier at the apex, however, in the long term, this medicament may increase the brittleness of dentin walls because of its hygroscopic and proteolytic properties, in addition to the disadvantage of requiring multiple appointments. A treatment option for young permanent teeth with necrotic pulps is pulp regeneration, whose advantage lies in the stimulation of new tissue formation within the root canal. Pulp revascularization is based on the disinfection of the root canal system, often performed with irrigating solutions and intracanal medicaments, accompanied by induction of periapical bleeding and formation of a blood clot that will fill the root canal. The aim of this study was to present a case of avulsion of teeth 11 and 21, both with open apices, treated with replantation associated with regenerative endodontic therapy, but varying the intracanal medicaments used: calcium hydroxide in tooth 11 and double antibiotic paste in tooth 21. Pulp revascularization proved to be effective with both intracanal medicaments used, promoting symptom resolution and complete root development, including apical closure, even in the absence of a well-defined clinical

Mussel‐Inspired Biocoating for Improving the Adhesion of Dental Pulp Stem Cells in Dental Pulp Regeneration

Dental pulp engineering possesses a promising perspective to replacing lost pulp in the root canal and restoring its functions. Stable adhesion of dental pulp stem cells (DPSCs) on the root canal dentin wall is a key element required for reconstruction of a functional odontoblast layer in dental pulp regeneration. To address this challenge, dopamine-modified hyaluronic acid (DA-HA) is coated on dentin to obtain a stable adhesion of DPSCs. The dopamine segment provides adhesion ability to the coating, and the hyaluronic acid increases the biocompatibility. The results show that DPSCs can adhere on the DA-HA coated dentin slice better than those without coating. Simultaneously, DPSCs proliferation can be further promoted on the prepared coating. Therefore, the DA-HA coating may provide a possible way to immobilize odontoblast cell onto dentin surface for pulp regeneration.

Pulp therapy in immature traumatized incisor using tricalcium silicate cement – a case report

Abstract Introduction: Traumatic injuries to immature permanent teeth are one of the most recurrent and urgent emergency treatment cases in pediatric dental practice. In many instances, the protocol for responding to this kind of emergency is not correct, and is not performed in a timely manner. Delays in seeking treatment following a complicated crown fracture in young individuals can result in irreversible pulpitis or pulp necrosis. It can leave a wide-open apex and brittle dentinal walls that are unfavorable to manage with conventional endodontic treatment (apexification). Materials and methods: The present report describes the clinical case of a complicated crown fracture in young permanent central incisor, with 18 months of clinical and radiographic follow-up. The traumatized incisor was successfully treated using a coronal pulpotomy technique and tricalcium silicate cement – BiodentineTM. Results: The presented treatment approach provided elimination of the symptoms, an absence of pain episodes, and positive reactions to pulp sensitivity tests. The follow up radiological assessment revealed evidence of a dentin bridge formation and continuation of root maturation. Conclusions: Coronal pulpotomies using tricalcium silicate cement are quick and easy to perform, and unlike endodontic treatment, preserve the tooth structure for the reattached tooth fragment. The restorative technique, the reattachment of fractured tooth fragment, and tooth restoration with a composite resin, represents an aesthetic, functional approach, and is an excellent and easy restorative option for clinicians and young impatient patients.

The effect of partial pulpotomy with iRoot BP Plus in traumatized immature permanent teeth: A randomized prospective controlled trial

A new bioceramic material iRoot BP Plus has been introduced and reported to have good biocompatibility, sealing ability and antibacterial activity. It has also been reported to be successfully used for procedures such as pulpotomy, pulp floor perforation repair and so on. However, there are only a few reports on the use of iRoot BP Plus in the management of traumatised teeth with an exposed pulp. The aim of this study was to investigate the clinical and radiographic outcomes of partial pulpotomy with iRoot BP Plus in immature permanent teeth with complicated crown fracture or complicated crown-root fracture. The study was prospectively designed and 110 immature permanent teeth with complicated crown fracture or complicated crown-root fracture were randomly allocated into two groups (n = 55). All teeth were clinically and radiographically assessed at 1, 3, 6, 12, 18 and 24 months after partial pulpotomy with iRoot BP Plus (experimental group, n=50) or calcium hydroxide (control group,n=49) as the pulp capping agent. Eleven cases were lost during follow-up, and 99 teeth were finally analysed. There were no intergroup differences in the survival rate, survival time, root length and dentin wall thickness. The calcific bridge was significantly thinner in the iRoot BP Plus group than in the calcium hydroxide group (0.97±0.13mm vs. 1.36±0.12mm; F=5.128, P=0.029). iRoot BP Plus may be an effective capping material for partial pulpotomy.

The Effects of Intracanal Irrigants and Medicaments on Dental-Derived Stem Cells Fate in Regenerative Endodontics: An update.

Regenerative endodontics is a biologically based treatment designed for immature permanent teeth with necrotic pulp to replace dentin and root structures, as well as dental pulp cells. This procedure has become a part of novel modality in endodontics therapeutic manner, and it is considered as an alternative to apexification. In the last decade, numerous case reports, which describe this procedure, have been published. This therapeutic approach succeeded due to its lower financial cost and ease of performance. Although the clinical protocol of this procedure is not standardized and the effects of irrigants and medicaments on dental stem cells fate remain somewhat ambiguous, however when successful, it is an improvement of endodontics treatment protocols which leads to continued root development, increased dentinal wall thickness, and apical closure of immature teeth. To ensure a successful regenerative procedure, it is essential to investigate the appropriate disinfection protocols and the use of biocompatible molecules in order to control the release of growth factors and the differentiation of stem cells. This is the first review in the literature to summarize the present knowledge regarding the effect of intracanal irrigants and medicaments on the dental derived stem cells fate in regenerative endodontic procedures.

Effects of Surface Treatments of Glass Fiber-Reinforced Post on Bond Strength to Root Dentine: A Systematic Review.

The objective of this systematic review was to determine the influence of surface treatment of glass fiber posts on bond strength to dentine. Laboratory studies were searched in MEDLINE, PubMed, Embase, PubMed Central, Scopus, and Web of Science search engine. All authors interdependently screened all identified articles for eligibility. The included studies were assessed for bias. Because of the considerable heterogeneity of the studies, a meta-analysis was not possible. Twelve articles were found eligible and included in the review. An assessment of the risk of bias in the included studies provided a result that classified the studies as low, medium, and high risk of bias. The available evidence indicated that the coronal region of the root canal bonded better to the glass fiber post than apical regions. Phosphoric acid, hydrogen peroxide, and silane application enhance post’s retentiveness. In light of the current evidence, surface treatment strategies increase the bond strength of glass fiber post to dentine. However, recommendations for standardized testing methods and reporting of future clinical studies are required to maintain clinically relevant information and to understand the effects of various surface treatment of glass fiber post and their bond strength with dentine walls of the root canal.

How Do Regenerative Endodontic Procedures Work for Immature Necrotic Teeth?

Treating an immature tooth with necrotic pulp has been a real challenge for dentists. Large immature canals without physiologic apical closure are difficult to debride, and restoring immature teeth with thin dentin walls is a challenge due to the tooth’s susceptibility to cervical root fracture. The majority of human case studies have shown good clinical outcomes such as the absence of clinical signs and symptoms, radiographic evidence of resolution of periapical infections, continued root development, and increased canal wall thickness for immature permanent teeth with pulpal necrosis following regenerative endodontic procedures (REPs). Furthermore, REPs have the potential to heal a necrotic pulp and restore functionality. This review compiles information on the principles and clinical protocols of REPs as well as their outcomes.

Morphological measurements of two separate mesiobuccal canals in maxillary first molars using micro-computed tomography.

To obtain radicular measurements of two separate mesiobuccal (MB) root canals in maxillary first molars using micro-computed tomography (μCT) with customized software. Human maxillary first molar MB roots (N = 36) with two separate canals (MB1, MB2) and apical foramina were scanned by μCT and analyzed with Kappa2 software to reconstruct three-dimensional (3D) surface models of roots and canals. These models were sectioned at 0.1mm intervals perpendicular to the central axis of each canal. Canal widths, 3D curvatures, and surrounding dentine thicknesses were measured concurrently on each section. Dentine thicknesses were analyzed statistically for differences between each direction and the different levels of both canals. Dentine walls around MB1 were thicker than MB2 (p < 0.05). Thinnest dentine was most often located at disto-inside direction in both canals. Canal widths were significantly smaller in MB2 than MB1 (p < 0.01). Apical constrictions were smaller (p < 0.05) and further (p < 0.05) from the apex in MB2 than MB1. Canal curvatures were greatest in the apical third of both canals (p < 0.001), and they were greater in MB2 than MB1 (p < 0.05). MB2 canals had shorter lengths, smaller widths, and more severe curvatures and were surrounded by thinner dentine walls. In MB2, apical constrictions were between 1 and 2mm from the apex, compared to about 1mm for MB1. These detailed measurements and in-depth 3D analyses of maxillary first molar MB roots with two separate canals and apical foramina provide morphologic references for root canal therapy.

Assessment of the Effect of Chitosan Nanoparticles on the Ultra-Structure of Dentinal Wall: A Comparative In vitroStudy

Assessment of the Effect of Chitosan Nanoparticles on the Ultra-Structure of Dentinal Wall: A Comparative In vitroStudy

Novel Bioactive and Therapeutic Root Canal Sealers with Antibacterial and Remineralization Properties.

According to the American Dental Association Survey of Dental Services Rendered (published in 2007), 15 million root canal treatment procedures are performed annually. Endodontic therapy relies mainly on biomechanical preparation, chemical irrigation and intracanal medicaments which play an important role in eliminating bacteria in the root canal. Furthermore, adequate obturation is essential to confine any residual bacteria within the root canal and deprive them of nutrients. However, numerous studies have shown that complete elimination of bacteria is not achieved due to the complex anatomy of the root canal system. There are several conventional antibiotic materials available in the market for endodontic use. However, the majority of these antibiotics and antiseptics provide short-term antibacterial effects, and they impose a risk of developing antibacterial resistance. The root canal is a dynamic environment, and antibacterial and antibiofilm materials with long-term effects and nonspecific mechanisms of action are highly desirable in such environments. In addition, the application of acidic solutions to the root canal wall can alter the dentin structure, resulting in a weaker and more brittle dentin. Root canal sealers with bioactive properties come in direct contact with the dentin wall and can play a positive role in bacterial elimination and strengthening of the root structure. The new generation of nanostructured, bioactive, antibacterial and remineralizing additives into polymeric resin-based root canal sealers are discussed in this review. The effects of these novel bioactive additives on the physical and sealing properties, as well as their biocompatibility, are all important factors that are presented in this article.

Viability and Stimulation of Human Stem Cells from the Apical Papilla (hSCAPs) Induced by Silicate-Based Materials for Their Potential Use in Regenerative Endodontics: A Systematic Review.

Blood clot formation in the apical third of the root canal system has been shown to promote further root development and reinforcement of dentinal walls by the deposition of mineralized tissue, resulting in an advancement from traditional apexification procedures to a regenerative endodontic treatment (RET) for non-vital immature permanent teeth. Silicate-based hydraulic biomaterials, categorized as bioactive endodontic cements, emerged as bright candidates for their use in RET as coronal barriers, sealing the previously induced blood clot scaffold. Human stem cells from the apical papilla (hSCAPs) surviving the infection may induce or at least be partially responsible for the regeneration or repair shown in RET. The aim of this study is to present a qualitative synthesis of available literature consisting of in vitro assays which analyzed the viability and stimulation of hSCAPs induced by silicate-based hydraulic biomaterials. A systematic electronic search was carried out in Medline, Scopus, Embase, Web of Science, Cochrane and SciELO databases, followed by a study selection, data extraction, and quality assessment following the PRISMA protocol. In vitro studies assessing the viability, proliferation, and/or differentiation of hSCAPs as well as their mineralization potential and/or osteogenic, odontogenic, cementogenic and/or angiogenic marker expression in contact with commercially available silicate-based materials were included in the present review. The search identified 73 preliminary references, of which 10 resulted to be eligible for qualitative synthesis. The modal materials studied were ProRoot MTA and Biodentine. Both bioceramic materials showed significant positive results when compared to a control for hSCAP cell viability, migration, and proliferation assays; a significant up-regulation of hSCAP odontogenic/osteogenic marker (ALP, DSPP, BSP, Runx2, OCN, OSX), angiogenic growth factor (VEGFA, FIGF) and pro-inflammatory cytokine (IL-1α, IL-1β, IL-6, TNF-α) expression; and a significant increase in hSCAP mineralized nodule formation assessed by Alizarin Red staining. Commercially available silicate-based materials considered in the present review can potentially induce mineralization and odontogenic/osteogenic differentiation of hSCAPs, thus prompting their use in regenerative endodontic procedures.

Effect of different laser types on bonding strength of CAD/CAM-customized zirconia post to root canal dentin: an experimental study.

In clinical dentistry, the strength of bonding zirconia posts to root canal dentinal walls currently needs enhancement, and laser application can be an important contribution owing to its features that accommodate adjustable modifications on dental materials. Herein, the effect of different laser treatments applied to dentin surfaces on the strength of bonding zirconia posts to root canal dentinal walls is evaluated by using the pull-out bond strength test in a laboratory setting. A total of 40 single-rooted permanent mandibular premolar teeth that were freshly extracted were used here. The root canal preparation steps were performed using the crown-down technique. Custom-made zirconia posts were produced using CAD/CAM technology. Prior to the application of resin cement, the internal surfaces of the root canals were irradiated using Nd:YAG, Er:YAG, and KTP lasers. Pull-out tests were performed on each specimen by using a universal testing machine. One-way analysis of variance and Tukey post hoc tests were used to compare the pull-out bond strength data. The bond strengths of the laser-treated specimens were greater than those of the untreated controls (p < 0.05). While the value of the pull-out bond strength after Nd:YAG laser treatment was significantly higher than the values obtained after the applications of the Er:YAG and KTP lasers (p < 0.05), the pull-out bond strength after Er:YAG laser treatment was considerably greater than that after KTP laser treatment (p < 0.05). The bond strength between the root canal dentin and the CAD/CAM custom-made zirconia post was improved upon using all the laser modalities in current laboratory settings, among which, application of the Nd:YAG laser was the most successful.

Bioinspired catechol chemistry for dentin remineralization: A new approach for the treatment of dentin hypersensitivity

ObjectiveDentin remineralization is of considerable clinical interest for dentin hypersensitivity and developing biomimetic analogs that can regulate hydroxyapatite (HAp) nucleation and growth remains a challenge. This study aimed to evaluate in vitro the potential for dentin remineralization using the following biomimetic in situ prepared poly(catechols): poly(dopamine), poly(DOPA), poly(caffeic acid) and a synthesized DOPA-peptide possessing collagen and calcium-binding domains (DOPA-Ahx-(Gly)3-(Glu)5). MethodsDentin samples were immersed in a freshly prepared phosphate-buffered saline (PBS) containing the respective catechol and laccase. After the reaction, they were immersed in calcium and phosphate remineralization solution, which was changed every day for 10 days. Samples of intact and demineralized dentin were used as control groups and kept in deionized water under the same experimental conditions. The remineralized dentin was characterized by scanning electron microscopy (SEM), Micro-energy dispersion X-ray fluorescence spectroscopy (μEDX) and X-ray diffraction (XRD). ResultsThe application of different poly(catechols) and DOPA-peptide promoted crystal nucleation and the formation of HAp, which partially covered both the dentin surface and dentinal tubules walls. SignificanceBy mimicking the role of charged non-collagenous proteins in vivo, polymers consisting of catechol groups showed the ability to modify demineralized dentin surface properties, promoting mineral formation. The use of poly(catechols) may be encouraged for the development of a therapeutic technique for dentin hypersensitivity.

Apical sealing ability of chitosan nanoparticles in epoxy-resin-based endodontic sealer

A good sealing ability of apical part of root canal system is needed to prevent microleakage thus resulting long-lasting successful treatment. Chitosan nanoparticles as nanofillers could be added to epoxy resin sealer to increase adaptation to dentinal wall. The purpose of this study was to evaluate the apical sealing ability of chitosan nanoparticles addition to epoxy-resin-based sealer. Thirty mandibular premolars were used in this study. The root canals were prepared using rotary files up to #30/0.09. The canal was irrigated with 2.5% NaOCl and 17% EDTA, then was rinsed with sterile water. All teeth were randomly divided into 3 groups (n=10). Group I was obturated with gutta-percha, Group II was obturated with gutta-percha and epoxy resin sealer, group III was obturated with gutta-percha and epoxy resin sealer that was added with chitosan nanoparticles. All specimens were stored in an incubator for 7 days at 37 °C. After that, specimens were tested with centrifuging dye penetration method with methylene blue 2% solution. The specimens were longitudinally sectioned, observed under stereomicroscope (8x magnification) and measured in millimeters (mm). The data were analyzed using one-way Anova. The results of one-way Anova showed that dye penetration in apical part of the root canal in all groups was statistically significant difference. The addition of chitosan nanoparticles to epoxy resin sealer increases the apical sealing ability of root canal obturation material.

Compartive Evalution of A New Endodontic Irrigation Solution –apple Vinegar, Ginger Oil And Sodium Hypochlorite to Remove The Smera Layer by Scaning Electron Microscope Study

Introduction: A three dimensional seal is the one of main steps in the successful root canal treatment .The smear layer that has been created on the dentinal wall during root canal instrumentation should be removed by using irrigation solution . Irrigation solution should be always used with mechanical preparation of root canal system as an important part for successful endodontic treatment Aim: The aim of this in vitro study was to compare the efficacy of four irrigating solutions in removing the smear layer. Materials and Methods: A total of 40 single rooted teeth were selected and instrumented and then assigned in a random manner into 4 groups of 10 each. Each group treated with different solutions (Normal saline, Sodium hypochlorite, Apple vinegar and Ginger oil). Scanning Electron Microscope had been used to measure the effect of these materials (solutions) in removal of smear layer from three root sections (Apical, middle and coronal third of the root). Conclusion: According to the Torbinjad criteria; Apple vinegar showed the best result in smear layer removal for the whole root length and no single irrigant can accomplish all the tasks required by irrigation.