Retrograde Cavity Research Articles

Spectrophotometric Analysis of Coronal Discolouration Induced by ProRoot MTA, Biodentine and MTA Repair HP Used for Pulpotomy Procedures.

Objective:To assess and quantify coronal tooth discolouration by ProRoot MTA, Biodentine and MTA repair HP as pulpotomy agents and to identify colour stability of these materials in presence of blood contamination.Methods:120 human premolar teeth were used in the study. The teeth were sectioned horizontally 1 mm apical to the cementoenamel junction. A retrograde cavity extending within 2 mm of the incisal edge was prepared. The specimens were randomly distributed as; Control; Group 1, ProRoot MTA: Group 2, Biodentine: Group 3 and MTA repair HP: Group 4. The groups werefurther subdivided on basis of exposure to saline (subgroup A) or blood (subgroup B). The access was sealed with light cured Glass ionomer cemet and the specimens were stored in artificial saliva at 37°C. The Colour change was evaluated with a spectrophotometer at: day 0 (T0), day 1 (T1), day 7 (T7), 1 month (T30), 2 months (T60), and 6 months (T180). The colour measurements were recorded using the Commission Internationale de l’Eclairage L*a*b* value.Results:For all groups, there was a sharp increase in L* parameter at T1. At 6 months, Group 1B (Control + blood) showed maximum decrease in luminosity followed by Group 2A (ProRoot + saline) > Group 4B (MTA repair HP + blood) > Group 2B (ProRoot + blood). Group 3A (Biodentine + saline) showed the least amount of decrease in luminosity followed by Group 4A (MTA repair HP + saline) and Group 3B (Biodentine + blood). No significant difference was found in ∆E change between any of the groups from baseline to 180 days (P>0.05).Conclusion:Relative to L* parameter, it was possible to observe a statistically significant decrease in luminosity in the Group1B (Control + blood) followed by ProRoot MTA (Group 2A and 2B) and MTA repair HP (Group 4A and 4B). Biodentine (Group 3A and 3B) showed least tooth discolouration in terms of L* parameter.

An In-vitro Fracture Strength Assessment of Endodontically Treated Teeth with Different Root-End Materials.

Objective:To assess and compare the fracture strength of endodontically treated teeth when the retrograde preparations were restored either with Biodentine or Endosequence BC RRM Fast set putty or Geristore.Methods:One hundred and twenty human mandibular premolars were used and allocated randomly into five groups (n=24 each). Following conventional root canal treatment, and apical root resection, retrograde cavities of 3 mm were prepared using ultrasonic tips. Group 1 (intact, sound teeth), Group 2 (without root-end filling), Groups 3, 4 and 5were allocated for Biodentine, Endosequence BC RRM putty, and Geristore respectively. Thermo-mechanical cyclic loading (TMC) was performed for one section of samples in each group (n=12 each) following which immediate and after TMC fracture resistance was evaluated using the Instron machine. One-way ANOVA followed by Tukey's multiple post-hoc procedures was used for data analysis.Results:Intact teeth had shown the highest fracture strength values than all other four groups (P<0.05) and resected roots without root-end filling group exhibited the lowest resistance to fracture. Amongst the test groups, Endosequence BC RRM putty displayed improved fracture strength, and Geristore exhibited the least resistance to fracture. Fracture strength values were not statistically different among Endosequence fast set putty and Biodentine group samples immediately and after thermo-mechanical cyclic loading (P=0.5987 and 0.9999 respectively). The fracture strength was notsignificantly different between Geristore and without root-end filling groups (P=0.3530).Conclusion:Endodontically treated teeth with Endosequence BC RRM putty or Biodentine root-end filled teeth had shown better fracture resistance compared to Geristore. Retrofilling with Geristore was not able to improve fracture strength of root canal-treated teeth.

Evaluation and comparison of the apical seal obtained with Biodentine after conditioning of root end with three different solutions using ultraviolet-visible spectrophotometer: An in vitro study

Aim: The aim of the study is to evaluate and compare the apical seal obtained with Biodentine after conditioning of root end with three different solutions (HEBP, chitosan, and ethylenediaminetetraacetic acid [EDTA]). Materials and Method: Forty-eight maxillary incisors were selected and decoronated. Instrumentation was done with protaper rotary files up to F4 file and obturated with AH plus sealer (Dentsply, Germany) and Protaper gutta-percha cone using lateral condensation technique. The apical part of each root was resected at 90° to the long axis of the root for 3 mm, and retrograde cavity preparation was done in standardized dimensions. The teeth were randomly divided into four groups with 12 samples in each group and later subjected to a standard regimen of 3 ml of respective solutions for 5 min: Group I – 18% HEBP, Group II – 0.2% chitosan, Group III – 17% EDTA, Group IV – saline (control). All teeth were then restored with Biodentine (Septodont, USA). Samples were coated with two coats of nail varnish except in the apical 3 mm which will be immersed in 5 ml of 2% methylene blue dye and stored in incubator for 72 h. The nail varnish will be removed later, and the teeth will be immersed in 35% nitric acid for 72 h. The solutions were then filtered using a fine-grit filter paper and centrifuged at 2000 rpm for 1 min. The solutions thus collected will be used to determine absorbency in ultraviolet-visible spectrophotometer. Results: The mean values of absorbance were greatest for Group IV (saline) followed by Group III (17% EDTA), Group II (0.2% chitosan), and Group I (18% HEBP). Group IV (saline) and Group III (17% EDTA) have got statistically significant difference with all the other groups. Group II has got statistically significant difference with all the other groups except Group I. Conclusion: Within the limitations of the study, it was concluded that irrigation with newer agents significantly influenced the sealing ability of biodentine. Root-end irrigation with 18% HEBP and 0.2% chitosan showed the least microleakage when compared to 17% EDTA.

Simultaneous Perio-endo Surgery with ER:YAG Laser and Bone Xenograft. A Case Report

Periodontally affected teeth with periapical lesion indicated for periapical surgery have a poor prognosis. Using Er:YAG lasers to perform simultaneous surgery on both defects may increase their survival rate. Preparing a retrograde cavity on affected teeth and obturating it is still a matter of debate among clinicians. The purpose of this case report was to describe the simultaneous use of Erbium-doped Yttrium Aluminium Garnet Er:YAG (2,940 nm) laser in the treatment of periapical granuloma and infraossal defect and the achieved results. The Er:YAG laser was used to perform flap dissection, granulation tissue removal, osteotomy and root-end resection except for initial flap incision and reflection. The cystic cavity was filled with Bio-Oss Collagen® xenograft. Results were followed up for 18 months with the help of radiographic orthopantomographic images. The outcome of this clinical case indicates that the use of Er:YAG laser could be considered a suitable method to perform simultaneous periodontal and endodontic surgery.

Effect of Blood Contamination on Marginal Adaptation of MTA and Endosequence Root Repair Material as a Retrograde Filling

Purpose: This study was designed to compare marginal adaptation of MTA and Endosequence Root Repair Material (ERRM) as retrograde filling materials. Materials and methods: 40 maxillary anterior teeth were prepared and obturated with gutta-percha and AH plus using lateral compaction technique. Apical 3mm of the roots were resected and retrograde cavities were prepared with diamond coated ultrasonic retrotip. Teeth were divided randomly into two main groups (I,II) according to blood contamination of retrograde cavities and every group then divided into two sub-groups (A,B) according to retrograde materials (MTA,ERRM). Teeth sectioned longitudinally and examined for marginal gap using SEM. Results: revealed that the high mean value in cavities without blood contamination and filled with MTA in group I and the high mean value in cavities smeed with blood contamination and filled with MTA in group II. There was no statistically significant difference between 4 groups. Conclusion: MTA and ERRM exhibited nearly comparable marginal adaptation in dry or blood environment.

Stress Analyses of Retrograde Cavity Preparation Designs for Surgical Endodontics in the Mesial Root of the Mandibular Molar: A Finite Element Analysis—Part II

IntroductionThe aim of this study was to investigate the influence of apical filling material and the modification made to the apical preparation design in surgical endodontics on the areas of stress concentration in the mesial root of a mandibular molar using finite element analysis. MethodsThe filling material was injected under 2 conditions (ie, with or without mineral trioxide aggregate retrograde filling). The apical preparation design was modified by extending the preparation mesially while maintaining a similar prepared area. We contained the displacement of all the nodes at the base of the supporting bone and applied a force of 150 N to the vertical axis. We analyzed stress generation and concentrations numerically for all cavity design groups. ResultsIn the presence of retrograde filling, the von Mises stress decreased gradually according to the enlargement of the prepared cavity in the subgroups. When the retrograde filling was absent, the von Mises stress increased as the prepared cavity enlarged. The modification of the apical preparation extending in the mesial direction showed a drastic decrease in stress concentration. ConclusionsWithin the limitations of this study, it was advantageous to perform mesial retrograde preparation within the mesial root dentin to maintain a balanced root dentin on both sides of the apical preparation and create a low-stress field. The surgeon should be careful not to wash out or dislodge the retrograde filling material during obturation to avoid failure of surgery.

Spectrophotometric analysis evaluating apical microleakage in retrograde filling using GIC, MTA and biodentine: an in-vitro study

BackgroundThe present study compares the apical microleakage of three different root-end filling materials in which the retrograde cavity is prepared by two different burs.MethodsEighty extracted single rooted maxillary and mandibular premolars were taken. Root canal treatment was completed. Apical 3 mm of all the teeth were resected with diamond disk. The tooth were divided into four groups with two subgroups for each group containing 10 tooth (N = 10) as: Group IA (Negative Control and IB (Positive Control); Group IIA and IIB: Prepared with round carbide bur and round diamond bur respectively, filled with GIC; Group IIIA and IIIB: Prepared with round carbide bur and round diamond bur respectively, filled with MTA; Group IVA and IVB: Prepared with round carbide bur and round diamond bur, filled with Biodentine. After applying two coats of nail varnish leaving apical 3 mm (except for negative control group) all teeth were immersed in 2% methylene blue for 3 days and again in 65% nitric acid for next 3 days for extraction of dye. The obtained solution was then transferred to eppendorf tube and centrifuged in microcentrifuges at 14,000 revolution per minutes (RPM) for 5 min. Optical density or absorbance of the supernatant solution was measured with UV spectrophotometer at 550 nm.ResultsThe absorbance of the supernatant solution after dye extraction is decreasing in the order of positive control> GIC > MTA > Biodentine> negative control group. The significant difference was observed between GIC and MTA (p = 0.0001) and GIC and Biodentine (p = 0.0001) with two different burs but statistically non-significant difference was observed between MTA and Biodentine with Carbide bur (p = 0.127) and Diamond bur (p = 0.496) respectively.ConclusionsWithin the limitations of the present study, it can be concluded that Biodentine and MTA showed less microleakage as compared to GIC. There is no significant difference between mean microleakage of MTA and Biodentine. However, the mean OD of the Biodentine was least of all evaluated materials. Preparation of the root-end using round carbide bur as well as round diamond burs showed comparable microleakage for all three filling materials.

The Effect of Root End Cavity Preparation Using Er,Cr:YSGG Laser, Ultrasonic Retrotip, and Bur on the Apical Microleakage of Retrograde Cavity Filled with MTA Plus.

ABSTRACTAim:The sealing ability of the retrograde material is greatly affected by the technique used for root end preparation. Advances in retrograde preparation techniques such as lasers has shown to provide an efficient outcome. The study was to evaluate and compare the effect of various techniques of retrograde cavity preparation on apical microleakage.Materials and Methods:Forty-five single rooted teeth were decoronated. Biomechanical preparation was carried out up to size F2 ProTaper system and obturated. Glass–ionomer cement was used as an access restorative material. The apical root resection was done at 3 mm from the apex at angulation of 90° to the long axis of the root. The allocation of the samples was done into three groups of 15 each. Group A: Retrograde cavities prepared using conventional round bur; Group B: Retrograde cavities prepared using ultrasonic retro preparation diamond tip; and Group C: Retrograde cavities prepared using “Erbium, chromium: yttrium, scandium, gallium, garnet” (Er,Cr:YSGG). The retrograde cavities hence prepared were filled with MTA Plus. Nail varnish was used to coat the samples except at the apical end. Samples were immersed in methylene blue for 24h. Stereomicroscope was used for examination of the sectioned teeth. The data were analyzed using one-way analysis of variance (ANOVA) and post hoc Tukey test.Results:Results showed very highly significant difference between laser and bur (P value = 0.001).Conclusion:Retrograde preparation with Er,Cr:YSGG showed significantly less microleakage when compared to the use of ultrasonic retrotip and burs.

Evaluation of the adhesion of human dental pulp stem cells to different endodontic biomaterials before and after setting.

Background. Stem cell-based treatment modalities have been potential strategies for tissue regeneration in many conditions. Several studies have evaluated the biologic properties of DPSCs and their efficacy in the treatment of a variety of diseases. The present study was undertaken to evaluate the adhesion behavior of DPSCs on different endodontic materials before and after setting. Methods. The crowns of the selected teeth were removed, and the root canals were prepared and obturated with gutta-percha and AH26 sealer. A retrograde cavity was prepared at root ends. Different materials were placed in the cavities. Then the samples were attached to the wells with the use of a chemical glue. Dental pulp stem cells were allowed to proliferate to reach a count of 2 million and transferred to -12well plates in association with a culture medium. Finally, the samples attached to the wells were exposed to the stem cells immersed in the culture medium before and after setting. Then adhesion of the stem cells was evaluated using SEM. Results. The SEM results showed cellular adhesion in the samples containing CEM cement both before and after setting. The samples containing MTA Angelus and ProRoot MTA exhibited cellular adhesion before setting, with no cellular adhesion after setting. The samples containing AH26 and MTA Fillapex sealers exhibited cellular adhesion after setting, with no adhesion before setting. The samples containing simvastatin exhibited no cellular adhesion before setting; this material had dissolved in the culture medium after setting evaluation. Conclusion. The results of the present study showed that of all the materials tested, CEM cement had the highest capacity for dental pulp stem cell adhesion.

Analysis of Stability in Time of Marginal Adaptation of Endosequence Root Repair Material on Biological Samples

Introduction: The introduction of mineral trioxide aggregate (MTA) and bioceramic sealers increased the success rate of endodontic surgery and perforation repair. The aim of this study was to evaluate the marginal adaptation at different times of endosequence root repair material (ERMM) in order to evaluate its dimensional stability using variable pressure-scanning electron microscope (VP-SEM). Material And Methods: Fourty-eight teeth were selected shaped up to a master apical size of 25. Then a 3 mm cut perpendicular to the long axis and a retrograde cavity preparation were performed. In order to obtain 2 mm thick sample a second cut was done and, in this disk, ERMM was inserted. The samples were stored at 37°. The samples were divided into four time-depending groups observed with VP-SEM at time 0 (Group 1) and after 2 (Group 2), 7 (Group 3) and 30 days (Group 4) after ERRM setting. Statistical analysis with one way-ANOVA test was performed (95%). Results: None of the four groups analyzed showed a complete marginal adaptation between dentin and ERRM. Instead, in all groups ERRM exhibited a completely preserved marginal adaptation to the dentin wall in all time-dependent groups. The mean (±SD) gap value was for time 0, 3.91 (±2.55) µm after 2 days, 4.32 (±2.69), after 7 days 4.49 (±2.53), and after 30 days 4.81 (±2.85) µm. No statistically significant difference was found between the four groups. Conclusions: The results of the present study demonstrate the dimensional stability over time of ERMM.

An in vitro Comparative Evaluation of the Sealing Ability of Five Different Root-end Filling Materials under Confocal Laser Microscopy.

Aim:The purpose of this in-vitro study was to compare and evaluate the best sealing ability of five different root end filling materials i.e. Silver Amalgam, RMGIC, Cermet Cement, MTA Angelus and Biodentine using ConFocal Laser Scanning Microscope.Methods and Material:90 extracted caries free, maxillary incisor teeth were collected and were root canal treated using standardized technique. Apical root resections followed by retrograde cavity preparation were done with ultrasonic retrotip. The teeth were divided into six groups depending upon different root end filling materials (Amalgam, RMGIC, Cermet cement, MTA, Biodentine) and one control group and apical leakage was observed under confocal laser scanning microscope.Statistical Analysis Used:The data was analyzed by ANOVA and Post Hoc test.Results:The mean dye penetration of different groups were Group I (Control Group) 0.00±(0.00) mm, Group II (Silver amalgam) 3.00±(0.00) mm, Group III (RMGIC) 1.84±(0.26) mm, Group IV (Cermet cement) 1.83 (0.25) mm, Group V (MTA) 1.25±(0.12) mm, Group VI (Biodentine) 0.26±(0.21) mm.Conclusion:It was concluded that Biodentine exhibits best sealing ability followed by mineral trioxide aggregate, followed by Cermet Cement and RMGIC, whereas silver amalgam exhibited least sealing ability.

Evaluation of Push Out Bond Strength of Two Calcium Silicate Based Cements with Bone Cement in Retrograde Cavities Prepared by Ultrasonic Retro Tips

Evaluation of Push Out Bond Strength of Two Calcium Silicate Based Cements with Bone Cement in Retrograde Cavities Prepared by Ultrasonic Retro Tips

Influence of blood contamination on the bond strength and biointeractivity of Biodentine used as root-end filling

AimTo evaluate the influence of blood contamination on the bond strength and apatite forming ability of Biodentine used as root-end filling material. MethodologyEighty (n = 80) extracted single-rooted, sound human maxillary anterior teeth were prepared and obturated. Then, the roots were resected, retrograde cavities were prepared and Biodentine was inserted as the root-end filling material. Teeth were then randomly divided into 2 equal groups (n = 40) according to the setting environment of Biodentine i.e., group A where setting took place in human blood and group B where setting took place in deionized water (control group). Teeth were incubated at 37 °C for 45 min to ensure complete setting. Root discs with the filling material in their core were prepared. Push-out bond strength test was performed using a universal testing machine and failure mode was examined. Both groups were aged in HBSS for 30 days. Apatite nucleation was evaluated at one-day, 7-days, and 30-days interval using SEM for morphological analysis and EDX for elemental analysis. Calculation of the Ca/P ratios was performed in addition to XRD for crystal phase analysis. ResultsBlood contamination (group A) resulted in significant reduction of bond strength values. It also affected the amount of apatite deposition on the material surface and interfacial spaces with higher Ca/P ratios than that of the normal stoichiometric hydroxyapatite. ConclusionsBlood contamination during setting of Biodentine had a detrimental effect on the bond strength and reduced the nucleation of apatite in comparison to non-contaminated group.

Evaluation of the dislodgement resistance of bioceramic reparative cements placed in a retrograde cavity using a different technique

Aim: Calcium silicate-based fillings have been widely used in surgical endodontic treatment because of hard-tissue conductive and inductive properties. The aim of present study is to investigate the bond strength of different calcium silicate-based fillings in retrograde cavities. Methods: Forty-four maxillary single rooted teeth were endodontically treated. The apical portions of the teeth were removed and root-end cavities were prepared using an ultrasonic tip. The roots were randomly divided into four experimental groups (n = 11) according to the material used; (1) MTA-FILLAPEX, (2) MTA Repair HP, (3) MTA-FILLAPEX+ MTA Repair HP, and (4) MTA Plus. Two horizontal cross sections (1±0.1 mm thick) from each specimen were resected from the apices. These sections were placed in a universal testing machine to evaluate the push-out bond strength force required for dislodgement of the root end filling was recorded. The failure type was also evaluated by using a stereomicroscope. The differences in bond strength were analyzed using the two-way analysis of variance (ANOVA). Results: MTA-FILLAPEX and MTA Plus displayed the lowest and highest dislocation resistance, respectively (P &lt; 0.05). In the apical level, bond strength was significantly higher than the coronal level in all groups except for MTA-FILLAPEX. Mixed failure was prevalent in all groups, except for MTA-FILLAPEX, which showed purely cohesive failures. Conclusions: Investigated calcium silicate-based filling materials showed different bond strength to the root-end cavity. The bond strength was significantly decreased when the prior application of MTA-FILLAPEX before delivery of MTA Repair HP.

Incorporating N-acetylcysteine and tricalcium phosphate into epoxy resin-based sealer improved its biocompatibility and adhesiveness to radicular dentine

ObjectiveThis in vitro study was designed to evaluate the biocompatibility, adhesiveness, and antimicrobial activity of epoxy resin-based sealer associated with N-Acetylcysteine (NAC) or beta-tricalcium phosphate nanoparticles (β-TCP) as an experimental retro-filling material. MethodsCytotoxicity was assessed using 2,3-Bis-(Methoxy-4-Nitro-5-Sulphophenyl)-2H-Tetrazolium-5-Carboxanilide (XTT) and Sulforhodamine B (SRB) assays after exposing human periodontal ligament fibroblasts to extracts of the materials for 1, 3, or 7 days. For the adhesive resistance test, root canals (48 single-root teeth) were instrumented with Reciproc #40 files (VDW GmbH, Germany) and obturated. After 7 days, the apices were sectioned and a retrograde cavity prepared and filled with the experimental materials (Mineral trioxide aggregate, Epoxy sealer, Epoxy sealer+NAC, and Epoxy sealer+β-TCP). For the push-out test, one 2-mm thick slice was obtained from the apical third of each specimen. Antimicrobial activity was performed using agar diffusion method. Biofilms were grown in microplates and exposed to the extracts of retro-filled materials, followed by analysis of growth inhibition on agar plates. ResultsEpoxy sealer in association with β-TCP or NAC showed better bond strength while Mineral trioxide aggregate allowed for the lowest adhesion. Mineral trioxide aggregate, Epoxy sealer+β-TCP, and Epoxy sealer+NAC showed low cytotoxicity. Epoxy sealer was the most cytotoxic. In antimicrobial activity assays, all materials had no effect on Candida albicans. Addition of NAC improved the antimicrobial property of Epoxy sealer against Enterococcus faecalis compared to unmodified Epoxy sealer (P<0.05). SignificanceIncorporating β-TCP or NAC with Epoxy sealer could improve the adhesiveness and biocompatibility for better use in endodontic therapy.

Influence of different laser-assisted retrograde cavity preparation techniques on bond strength of bioceramic-based material to root dentine.

The purposes of the study were to evaluate the bond strength of bioceramic TotalFill root repair material (RRM) in retrograde cavities prepared using Er:YAG and Er,Cr:YSGG laser and steel bur, and to analyze failure modes. The root canals of 30 single-rooted teeth were endodontically treated, their root-ends were resected using a diamond bur, and the teeth were randomly divided into three groups (N= 10) according to the retrograde cavity preparation technique: (1) Er:YAG laser, (2) Er,Cr:YSGG laser, and (3) steel bur. All retrograde cavities were filled with the TotalFill RRM which was prepared according to the manufacturers' instructions. Push-out test was performed using universal testing machine, and failure mode was analyzed using a scanning electron microscope. The data were analyzed using one-way ANOVA, post hoc analysis with Bonferroni correction, and Fisher-Freeman-Halton exact test (p< 0.05). In the Er:YAG-, Er,Cr:YSGG-, and steel bur-prepared cavities, mean bond strengths (MPa) were 12.76, 8.44, and 6.01, respectively. The bond strength of the TotalFill RRM to dentin was significantly higher in the Er:YAG laser compared with the steel bur-prepared cavities (p= 0.004). The bond strength was not significantly different between the Er:YAG and Er,Cr:YSGG cavities (p= 0.074) and between the Er,Cr:YSGG and bur cavities (p= 0.648). In the cavities prepared by the Er,Cr:YSGG laser and bur, the failure mode of the TotalFill RRM was predominantly mixed, then adhesive and cohesive. In the Er:YAG laser-prepared cavities, the most common failure mode was adhesive, followed by mixed type and no cohesive failure. The bond strength of the TotalFill RRM to dentin was highest in the group of retrograde cavities prepared by the Er:YAG laser.

Stress Analyses of Retrograde Cavity Preparation Designs for Surgical Endodontics in the Mesial Root of the Mandibular Molar: A Finite Element Analysis—Part I

IntroductionThe aim of this study was to investigate the influence of various apical preparation designs for surgical endodontics on stress concentrations in the mesial root of the mandibular molar under different experimental conditions using finite element analysis. MethodsWe designed 2 apical preparation groups according to whether an isthmus was present or not. Each group contained 4 subgroups according to the size of the apical preparation. We constrained the displacement of all nodes at the base of the supporting bone and applied a force of 150 N to the vertical axis. We analyzed stress generation and concentrations numerically for the groups and subgroups. ResultsIn the subgroups, the von Mises and maximum principal stresses reduced gradually according to the enlargement of the prepared cavity. However, when the preparation extended excessively in the isthmus preparation groups, the situation reversed (ie, both von Mises and maximum principal stresses increased). ConclusionsWithin the limitations of this study, the apical preparation design influenced the distribution of stress concentration. Unlike the overall pattern in which stress decreased as the amount of apical preparation increased, stress increased when the amount of residual dentin was extremely thin.

Scanning electron microscopy evaluation of chitosan and carboxymethyl chitosan as retrograde smear layer removing agents.

Background:The smear layer acts as a physical barrier against penetration of root canal medicaments and sealers, thus compromising the seal leading to microleakage.Objectives:This study was conducted to evaluate the efficacy of 17% ethylenediaminetetraacetic acid (EDTA), 0.2% chitosan solution, and 0.2% carboxymethyl chitosan (CMC) used as smear layer removing agents in retrograde root canal preparation using scanning electron microscopy (SEM).Materials and Methodology:Eighty single-rooted teeth extracted for periodontal reasons were collected for the study. Root canals were prepared and obturated with gutta-percha coated with AH plus resin sealer. Apical 3 mm of each root resected and Class I retrograde preparation carried out using ultrasonic handpiece and ultrasonic retro tips to a depth of 3 mm along the root long axis. In Group 1 (control), normal saline solution alone was used for smear layer removal. In Group II, 17% EDTA, Group III and IV were treated with 5 ml of 0.2% chitosan and 0.2% carboxyl methyl chitosan, respectively, for 3 min. Blinded evaluation of specimens using SEM was performed independently by two operators who registered the amount of the smear layer present on the surface of the canal walls based on the score described by Hülsmann et al.Results:Group I (saline) was least efficient in the removal of the smear layer. Group II (17% EDTA), Group III (0.2% Chitosan), and Group IV (0.2% CMC) efficiently removed the smear layer from the retrograde cavity with mean scores 1.35, 1.60, and 1.35, respectively. Statistically, no significant difference found in Group II (17% EDTA), Group III (0.2% Chitosan), and Group IV (0.2% CMC).Conclusions:About 0.2% CMC and 0.2% chitosan can be better alternatives to 17% EDTA for smear layer removal due to their biological advantages.

Comparative Evaluation of Apical Microleakage of Retrograde Cavities Filled with Glass Ionomer Cement, Light-cured Composite, Mineral Trioxide Aggregate and Biodentine

Comparative Evaluation of Apical Microleakage of Retrograde Cavities Filled with Glass Ionomer Cement, Light-cured Composite, Mineral Trioxide Aggregate and Biodentine

Intentional replantation of endodontically treated second premolar with chronic apical abscess

A case of 51-year-old female reported with pain of failed root canal treatment of the mandibular right second premolar. Periapical lesion, mobility, and deep periodontal pocket were detected during examination. Intentional replantation was discussed with the patient. The tooth was atraumatically extracted followed by root end resection and retrograde cavity preparation and filling with MTA. Curettage in conjunction with irrigation of the alveolus was considered to eliminate the inflammatory tissue. The tooth was replanted back into its socket and splinted to the adjacent tooth. The total extraoral treatment time was ≤15 min. One- and three-month follow-up revealed no clinical symptoms and progressive periapical healing. After 2 years and 7 months, complete periapical healing was evident. The success rate of intentional replantation is very promising when the procedural techniques are applied properly.