Smear Layer Removal Research Articles

Effectiveness of EndoActivator, PATS Vario system, and XP-endo Finisher files on smear layer removal under scanning electron microscope: A comparative study.

The smear layer may harbor many bacteria; hence, alternative methods are used to disrupt and remove biofilm. The aim of the study was to compare the effectiveness of EndoActivator, PATS Vario System, and XP-endo Finisher files on smear layer removal using a scanning electron microscope. Sixty single-rooted extracted premolars with Vertucci Type 1 configuration were decoronated and divided into four groups. The groups were instrumented with the rotary ProTaper file system. All specimens were flushed with 1 ml of 3% sodium hypochlorite. Group 1 was irrigated with a conventional needle and syringe. In Group 2, the irrigant was activated with an EndoActivator. In Group 3, the irrigant was activated with PATS Vario system, and in Group 4, XP-endo Finisher files were used after biomechanical preparation to remove debris and smear layer. All specimens were finally rinsed with 3 ml of 3% sodium hypochlorite. The teeth underwent longitudinal splitting and grooving in the coronal, middle, and apical thirds, and then, the samples were taken for scanning electron microscopy to evaluate the amount of smear layer removal in each third. The middle and coronal thirds Showed that almost similar efficacy to remove smear layer in both Group II and Group III. At the apical third, Group III showed comparatively better results than Group I, II, and IV, respectively. Equal amount of smear layer was seen with EndoActivator and PATS Vario system when used as sonic irrigation devices.

The Efficacy of Nano Magnesium Oxide and Nano Silver Fluoride on Canal Cleanliness and Smear Layer Removal (An In Vitro Study).

The Efficacy of Nano Magnesium Oxide and Nano Silver Fluoride on Canal Cleanliness and Smear Layer Removal (An In Vitro Study).

Assessment of Smear Layer Removal and Penetration Depth of Root Canal Irrigant Using Different Irrigation Activation Systems: A Comparative Study.

The aim of the current study was to evaluate the penetration depth and smear layer removal of root canal irrigant using various irrigation activation techniques. In this investigation, sixty single-rooted premolars extracted for orthodontic purposes were chosen. Diamond burs were used to create an access cavity, and #10 K-file was used to determine the patency. About sixty samples were divided into the following three groups (20 samples in each group), group I: Irrigation with conventional needle, group II: Activation of EndoVac system, group III: Passive ultrasonic irrigation (PUI). The efficacy of the smear layer was assessed using a scanning electron microscopy at a ×2000 magnification. One-way ANOVA was used to record and analyze the data. All statistical analyses were performed with a significance level of p < 0.05. At coronal third, the maximum smear layer was removed in group II (1.26 ± 0.02) followed by group III (1.84 ± 0.16) and group I (2.89 ± 0.21). At middle third, smear layer removal was maximum in group I (1.18 ± 0.10) followed by group III (1.72 ± 0.09) and group I (2.66 ± 0.18). At apical third, the more smear layer was removed in group II (1.02 ± 0.01) followed by group III (1.58 ± 0.08) and group I (2.38 ± 0.06). There was a highly significant difference found between the three different irrigation systems at all three levels (p < 0.001). In conclusion, every irrigation device that was evaluated was successful in removing the smear layer from the root canal. However, the EndoVac system group removed a greater amount of smear layer compared with PUI and conventional needle group. With the goal of promoting cleaning that is beyond the ability of mechanical devices, irrigation is a crucial part of root canal therapy. If an efficient irrigation delivery system is used, the irrigants can reach the working length (WL). This type of distribution system needs to provide a suitable amount of irrigants up to the WL, as well as have enough flow and be effective at debriding the entire canal system. How to cite this article: Pujari MD, Das M, Das A, et al. Assessment of Smear Layer Removal and Penetration Depth of Root Canal Irrigant Using Different Irrigation Activation Systems: A Comparative Study. J Contemp Dent Pract 2024;25(4):331-334.

Evaluation of the Smear Layer Removal Ability of Various Rotary Files with/without Chemical Agents on Primary Teeth: An In Vitro Study.

The aim of the current study was to assess the cleaning and smear layer removal efficacy of two different rotary files with or without chemical agents on primary teeth. For the study, 90 extracted primary maxillary incisors without internal or external resorption and with at least two-thirds of complete roots were chosen. Then, based on the kind of instruments used to clean and shape the canals, they were randomly assigned to three experimental groups, each consisting of 30 teeth. Group-I: The canal was instrumented manually with K-files, Group-II: The canal was instrumented with Kedo-S files, Group-III: The canal was instrumented with Kedo-SG Blue files. After the canals were finally instrumented, 2 mL of QMixTM solution was used to irrigate 15 samples from each group. The samples were subsequently allowed to remain in the canals for 90 seconds in order to eliminate the smear layer. After that a stereomicroscope was used to assess the cleaning effectiveness. With irrigant solution, the highest mean value was found in manual K-files (2.86 ± 0.34), followed by Kedo-S files group (1.34 ± 0.26) and Kedo-SG Blue files (1.28 ± 0.18). Without irrigant solution, the highest mean value was found in manual K-files (2.92 ± 0.22) followed by Kedo-S files group (1.44 ± 0.18) and Kedo-SG Blue files (1.36 ± 0.14). There was a statistically significant difference found at all the three levels. On conclusion, the current study's findings demonstrated that irrigation solution was significantly more effective in cleaning and removing smear layers from pediatric rotary files than manual K-files. The effectiveness of endodontic therapy depends on a successful chemomechanical preparation. The canals are instrumented using either hand files or rotary instruments; there are several irrigation and instrumentation techniques. In order to completely sterilize the canals, chemical agents are utilized for irrigation during instrumentation. Due to their numerous biological, antibacterial, anti-inflammatory, and antioxidant qualities, many natural compounds are also utilized as irrigants. How to cite this article: Abushanan A. Evaluation of the Smear Layer Removal Ability of Various Rotary Files with/without Chemical Agents on Primary Teeth: An In Vitro Study. J Contemp Dent Pract 2024;25(4):354-357.

Qualitative and Quantitative Evaluation of the Effects of Different Chelating Agents on the Calcium Content of Root Canal Dentin Using Atomic Absorption Spectrophotometer: An In Vitro Study.

Evaluation of the effects of different chelating agents on the calcium loss of root canal dentin. Around 65 single-rooted teeth were collected and decoronated. The working length was determined, and biomechanical preparation was done in a crown-down fashion using the HyFlex Control Memory rotary nickel-titanium (Ni-Ti) system until apical preparation of 30.04. Canals were irrigated with chelating agents and sodium hypochlorite between each file insertion. Based on the type of chelating agents used, the samples were randomly divided into five groups (n = 13)-group I, liquid ethylenediaminetetraacetic acid (EDTA); group II, EDTA and chlorhexidine (CHX); group III, etidronic acid; group IV, SmearClear; and group V (control), distilled water. The total volume of the solution used was collected, and calcium ion release was quantified using an atomic absorption spectrophotometer. The qualitative analysis was done by observing the acetylene (C2H2)/air flame. Images were obtained for each sample, compared, and analyzed. With respect to the control group, groups IV and I show a statistically significant difference compared to groups II and III (p < 0.05). Qualitatively, the highest intensity was observed in group IV and the least intensity in group III. SmearClear showed significantly higher decalcifying capability compared to EDTA, EDTA and CHX, and etidronic acid. Hence, its combined use with an organic solvent can be recommended for efficient smear layer removal. Minimally invasive endodontic treatment is aimed at preserving the strength of the treated tooth without compromising cleaning effectiveness. Therefore, comparing the efficacy of different chelating agents will be promising with respect to maximum calcium loss both qualitatively and quantitatively. Singhal P, Raisingani D, Prasad AB, et al. Qualitative and Quantitative Evaluation of the Effects of Different Chelating Agents on the Calcium Content of Root Canal Dentin Using Atomic Absorption Spectrophotometer: An In Vitro Study. Int J Clin Pediatr Dent 2024;17(6):647-652.

Water-soluble vitamin-E for enhancing fluorescence diagnosis in infected human dentine treated with NaOCl

IntroductionBacterial fluorescence methods are of interest in endodontics for informing endpoints for debridement. This study explored potential fluorescence quenching reversal effects of a water-soluble vitamin E conjugate (d-α-Tocopherol polyethylene glycol 1000 succinate, TPGS) when applied to polymicrobial biofilms grown on dentine that had been exposed to sodium hypochlorite (NaOCl) to cause quenching. MethodExtracted human teeth were debrided, embedded in transparent acrylic resin and sectioned. After smear layer removal, tooth dentine sections were inoculated with a polymicrobial inoculum, and cultured for 7 days to create biofilms. Samples (n = 8 per group) were exposed to 1 % or 4 % NaOCl for 2 or 4 min, and then treated with TPGS. Bacterial fluorescence readings under laser excitation at 655 nm were assessed over 10 min using a calibrated DIAGNOdent device. All data were assessed for normality (Kolmogorov-Smirnov test) and analysed with ANOVA followed by Bonferroni post-hoc tests. ResultsNaOCl at both concentrations quenched fluorescence readings of biofilms grown on dentine samples, with a maximal reduction of 40.4 % at 5 min after 4 % NaOCl. Treatment with TPGS gave faster recovery of fluorescence readings compared to the control at 5 and 10 min. ConclusionThe water-soluble antioxidant TPGS partially reversed fluorescence quenching caused by NaOCl. This agent may have value clinically for reducing the time needed for fluorescence readings to recover when NaOCl is used as an irrigant. This will facilitate more accurate assessment of endpoints for canal debridement.

Comparative Evaluation of Ultrasonic and Sonic Irrigant Activation Systems: Assessing Extrusion Risk, Debridement, and Biofilm Removal in Distinct Apical Preparation Sizes

This study aims to compare the effectiveness of ultrasonically and sonically activated irrigation in terms of extrusion risk, root canal debridement, and biofilm removal, considering distinct apical preparation sizes, through an ex vivo study in human teeth. Instrumented teeth, to an apical size of 35/.06 or 50/.06, were assigned to three different irrigation procedures: ultrasonically activated irrigation, sonically activated irrigation, and conventional manual irrigation. Apical extrusion risk was evaluated by quantifying irrigant and debris extrusion (n = 10/group). Debris evaluation and smear layer removal from the root canal wall were conducted by scanning electron microscopy (SEM) (n = 5/group), and the elimination of a mature biofilm of Enterococcus faecalis was assessed through resazurin assay and SEM (n = 10/group). For statistical analyses, Student’s paired t-test and the ANOVA with post-hoc Tukey were used. Activated irrigations exhibited a higher risk of extrusion for the larger apical size, while the risk for manual irrigation remained independent of the apical size. Substantially fewer residual debris and smear layers were observed after the activation of the irrigant, and there was a notable enhancement in biofilm elimination compared to manual irrigation (p &lt; 0.05). Notably, the effectiveness of both activated irrigations was more pronounced in root canals prepared to a size 50/.06, with ultrasonic activation showing enhanced improvements. The findings of this study underscore the substantial impact of both ultrasonically and sonically activated irrigation on the effectiveness of root canal disinfection and debridement. This impact is especially prominent with larger apical size, albeit accompanied by an increased risk of extrusion.

Effect of Using 5% Apple Vinegar Irrigation Solution Adjunct to Diode Laser on Smear Layer Removal and Calcium/Phosphorus Ion Ratio during Root Canal Treatment

Effect of Using 5% Apple Vinegar Irrigation Solution Adjunct to Diode Laser on Smear Layer Removal and Calcium/Phosphorus Ion Ratio during Root Canal Treatment

Canal disinfection using Nd: YAG Laser, synchronized microbubble-photodynamic activation, and carbon quantum dots on microhardness, smear layer removal, and extrusion bond strength of zirconia post to canal dentin. An invitro scanning electron microscopic analysis.

Evaluation of the impact of the latest root canal disinfectant, that is carbon quantum dots (CQDs), synchronized microbubble-photodynamic activation (SYMPA), and Nd: YAG laser along with ethylenediaminetetraacetic acid (EDTA) as a final irrigant on the Marten hardness (MH), smear layer (SL) removal, and extrusion bond strength (EBS) of zirconia post to the canal dentin. Eighty intact single-rooted premolars were obtained and disinfected using 0.5% chloramine-T solution. Root canal preparation was performed using ProTaper files followed by obturation. The post space was prepared for prefabricated zirconia post and all the teeth were randomly divided into four groups based on the disinfection used (n = 20 each) Group 1: 5.25% NaOCl + 17% EDTA (Control), Group 2: Nd: YAG laser + 17% EDTA, Group 3: SYMPA + 17% EDTA, and Group 4: CQDs + 17% EDTA. MH, SL removal, and EBS of zirconia post-bonded to root dentin were performed using a microhardness tester, scanning electron microscope (SEM), and universal testing machine, respectively. Both intragroup and intergroup comparisons were performed using one-way analysis of variance (ANOVA) and posthoc-Tukey test for significant difference (p < .05). Group 2 samples (Nd: YAG laser + 17% EDTA) (0.24 ± 0.06 GPa) exhibited highest values of MH. Samples in group 3 (SYMPA + 17% EDTA) treated teeth unveiled the lowest MH scores (0.13 ± 0.02 GPa). Moreover, the coronal third of Group 3 specimens (SYMPA and 17% EDTA) (1.54 ± 0.31) eliminated SL from the canal with the greatest efficacy as well as presented the highest EBS (10.13 ± 0.69 MPa). However, the apical third of Group 1 samples (5.25% NaOCl + 17% EDTA) (2.95 ± 0.33) exhibited the least efficient elimination of SL from the radicular dentin as well as the lowest bond strength (5.11 ± 0.19 MPa) of zirconia post to the dentin. The SYMPA technique with 17% EDTA proved highly effective in removing the SL from canal dentin and enhancing the EBS of zirconia posts. The least preferable method for SL removal and MH improvement was found to be 5.25% NaOCl + 17% EDTA. CQDs and Nd: YAG laser demonstrated satisfactory smear layer removal properties from the canal, along with achieving appropriate bond strength of zirconia posts. RESEARCH HIGHLIGHTS: Nd: YAG laser and 17% EDTA as canal disinfectant exhibited the highest values of MH. Specimens irrigated with SYMPA and 17% EDTA eliminated SL from the canal with the greatest efficacy. The coronal third of Group 3 (SYMPA + 17% EDTA) samples unveiled the highest zirconia post-bond integrity score to the canal dentin. Cohesive failure was a dominant failure type among different experimental groups.

High-Intensity Focused Ultrasound in Dentistry: A Literature Review

Although high-intensity focused ultrasound (HIFU) has been applied widely in medicine, utilising its non-invasive dual ablation and thermal coagulation properties, its application in dentistry has primarily remained in the research phase, predominantly in in vitro studies. Nonetheless, there has been a consistent increase in the number of publications on this subject in recent decades, focusing on areas such as remineralisation of dentine surfaces, removal of smear layers, drug delivery, and microbial elimination. The number of advantages HIFU can offer, such as its non-surgical nature, absence of ionising radiation, lack of residue, and absence of aerosols, is driving this upward trend, indicating the potential for HIFU in clinical dentistry and ongoing efforts towards developing HIFU-based devices for routine dental use. This succinct review aims to outline the historical context, operational mechanisms of HIFU, summarise recent dental research, and provide a forward-looking perspective on the role of HIFU in modern clinical dentistry.

Efficiency of Canal Brush and Ultrasonic Activated Irrigation in Smear Layer Removal Using Two Different Chelating Agents (In Vitro Study)

Objective: This study aims to evaluate the efficiency of two different activation methods after using two different chelating agents inthe removal of the smear layer.&#x0D; Methods: In this study, seventy single-rooted mandibular premolar teeth were included, and divided into six study groups and onecontrol group according to the chelating agents and activation methods used. In groups 1,3, and 5, EDTA was used as the chelatingagent, where it was activated by Canal Brush in G3 and by Ultra Smart in G5. In groups 2,4, and 6, 7% Maleic acid was used insteadand activated by Canal Brush in G4 and Ultra Smart in G6. While in G1 and G2, no activation systems were used. The 7th group wasa negative control and purposed to verify the internal microstructure, so only distal water was irrigated (no activation and no chelatingagent was used). Samples were sectioned longitudinally and prepared for Scanning Electron Microscope (SEM) analysis in the coronal,middle, and apical parts. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney U tests. The level of significancewas set to 0.05 (P &lt; 0.05).&#x0D; Results: Although the G5 (Ultra Smart +EDTA) median score showed the best smear layer removal score, it was not statisticallysignificant in comparison with the other 5 study groups. In all groups (whether Maleic acid or EDTA were used), smear layer removalwas effective in the coronal and middle thirds while less effective in the apical third, with no statistically significant difference betweenthe chelating agents.&#x0D; Conclusions: Under the limitations of this in vitro study, no activation system was able to remove the smear layer from the root canalwall completely. However, NaOCl and EDTA's irrigation sequence combined with Ultra Smart (ultrasonic activation) obtained betterresults than the other techniques.

Effectiveness of Chitosan Oligosaccharide as Chelating agent in Smear Layer Removal and The effect on Fracture Resistance of Endodontically Treated Teeth

One factor affecting root canal treatment's success is the cleanliness of root canal systems. Smear layer removal is needed to ensure the cleanliness of root canals. Fracture resistance is also essential things in endodontic-treated teeth. Chitosan is one of the irrigant alternatives in dentistry that is biocompatible. The study aimed to investigate the effect of chitosan oligosaccharide as a root canal chelating alternative in the cleaning smear layer and its impact on fracture resistance of endodontic treated teeth.Experimental research with 56 mandibular premolar teeth with a single canal was used. For the smear layer cleanliness test, 24 teeth were used and divided into four treatment groups. Statistical analysis used was the one‑way analysis of variance and LSD Post Hoc test. Thirty-two teeth were divided into two treatment groups for the fracture resistance test. The statistical analysis used was the Independent T-test. There was no significant difference between smear layer removal in chitosan oligosaccharide 2% and EDTA 17% groups. There was a considerable difference between fracture resistance of endodontic treated teeth in chitosan oligosaccharide 2% and EDTA 17% groups. Chitosan oligosaccharide 2% can be used as an alternative in the final irrigation of root canal treatment.

Combined use of XP-Endo Finisher and different chelating agents on the smear layer

ABSTRACT Aims: The aim of this study was to assess the effect of XP-Endo Finisher (XPF) in conjunction with three different chelating agents, namely, 0.2% chitosan nanoparticles (CNP), 17% ethylenediaminetetraacetic acid (EDTA), and 7% maleic acid (MA) on residual debris and smear layer on the root canal walls of the mandibular premolars. Materials and Methods: Eighty extracted human mandibular premolars were used in the study. Canals were prepared using an XP-Endo Shaper, and the final finishing was done with an XPF file. Teeth were randomly divided into four experimental groups based on chelating agents, Group I (XPF + 0.2% CNP), Group II (XPF + 17% EDTA), Group III (XPF + MA), and Group IV XPF + 2.5% sodium hypochlorite (NaOCl) (control group). Teeth were longitudinally split and prepared for scanning electron microscopy analysis. For comparing the smear layer and debris score between groups, the Kruskal–Wallis ANOVA was used, followed by the post hoc Bonferroni test. The level of significance was set at P &lt; 0.05. Results: Group I (XPF + 0.2% CNP) gave the best results (P = 0.001) in all the thirds of root canal, followed by Group II (XPF + 17% EDTA) with P = 0.001. Group III (XPF + MA) showed results similar to that of the control group (XPF + NaOCl) with P = 0.001. There was a significant difference in the scores between Group I (XPF + CNP) and the other three groups. Conclusion: In all three-thirds of a root canal, the use of XPF + 0.2% CNP performed best at removing the smear layer. This was followed by XPF + 17% EDTA and XPF + 7% MA. For all groups, smear layer removal was less efficient in the apical third.

Assessment of the Smear Layer Removal Efficacy of Three Different Agents on Periodontally Compromised Tooth: An In Vitro Study.

The purpose of the present study was to evaluate the smear layer removal efficacy of three various agents on periodontally compromised tooth. The current study included 75 molar teeth that were extracted due to periodontal disease. After that, 25 samples were randomly assigned using a simple random technique to the three different agent groups, group A: Scaling and root planing (SRP) and application of SofScale agent, group B: SRP and application of QMix agent, group C: SRP and application of MTAD agent. Using a diamond circular saw, the treated portions were divided into horizontal and vertical halves. All samples were viewed under Scanning Electron Microscope. Every tooth was focused at the coronal third, middle third, and apical third portion with a magnification of 1000×. Data were recorded and statistically analyzed. The smear layer removal efficacy was more in the QMix agent (3.06 ± 0.04) group followed by MTAD agent (3.28 ± 0.09) and SofScale agent (4.14 ± 0.10) group on the root surface. On intra group comparison, there was a statistically significant difference found in all the intra group agents with all the three levels. On inter group evaluation, at coronal third, there was no significant difference found between the different agents. There was a significant difference found between the different agents at middle and coronal third. On conclusion, the current investigation found that, the root surfaces treated with QMix shown a greater ability to remove smear layers compared to tooth surfaces treated with MTAD and SofScale agent. Conventional therapies such as SRP effectively eliminate calculus, plaque, and necrosed cementum; nevertheless, they leave behind a smear layer that could impede normal healing. In an effort to overcome this, root conditioning agents were applied on the root surface to remove the smear layer. The traditional root conditioning agents such as citric acid have certain disadvantages, though, such as an acidic pH that could harm the root surface. As a result, researchers have been looking for biocompatible root conditioning treatments that are more effective. How to cite this article: Singh DK, BS Raj H, Soans CR, et al. Assessment of the Smear Layer Removal Efficacy of Three Different Agents on Periodontally Compromised Tooth: An In Vitro Study. J Contemp Dent Pract 2024;25(2):156-159.

Comparative evaluation of smear layer removal by using different irrigant activation techniques: An in vitro scanning electron microscopic study.

This in vitro study aims to assess and compare the effectiveness of different irrigation activation techniques in removing the smear layer from the root canal dentin using Scanning electron microscope (SEM) analysis. A total of 60 extracted single-rooted premolar with straight canal and mature apex were used for this study. After the selection of teeth, all the samples were decoronated followed by biomechanical preparation. The sample after preparation was irrigated with sodium hypochlorite and randomly divided into three groups with 20 sample in each group (n = 20), (Group 1) control, (Group 2) ultrasonic, and (Group 3) laser. The irrigant activation was done in all the groups and then sample was prepared for the scanning electron microscope analysis. The statistical analysis was performed using the Mann-Whitney-U-test. The findings suggested that the diode laser irrigant activation technique was superior to the ultrasonic and conventional techniques to eradicate smear layers. With the limitation of this study, diode laser activation showed better cleaning of root dentinal walls compared to ultrasonic activator and traditional method.

Debris and Smear Layer Removal in Curved Root Canals: A Comparative Study of Ultrasonic and Sonic Irrigant Activation Techniques.

The aim of this study was to compare the cleaning efficacy of three irrigant activation devices with a control of non-activated syringe and needle irrigation in curved root canals. Sixty human curved roots were endodontically prepared and divided into four groups (n = 15) with similar root curvature distributions. Final irrigation using 4% NaOCl was performed with a syringe and needle (30-G) alone, or with Eddy sonic powered irrigation system (polymeric tip #0.25/0.06), Endosonic ultrasonic activation (polymeric tip #0.25/0.03), or Irrisafe ultrasonic activation (stainless-steel tip, #0.25/0.00). SEM was used to evaluate cleaning efficacy, employing five-score systems for debris and smear layer. While no significant difference in debris removal was observed between Endosonic or Irrisafe activation and non-activated irrigation, Eddy sonic powered irrigation system significantly improved debris removal in the apical third of curved root canals. Smear layer removal was effective in coronal and mid-root sections for all groups but less so in the apical third. Thus, Eddy sonic powered irrigation system demonstrated higher efficacy in removing debris from the apical third of curved root canals compared with non-activated syringe and needle irrigation. However, all three irrigant activation systems exhibited no difference from the non-activated control in smear layer removal.

Comparative Evaluation of Antimicrobial and Smear Layer Removal Efficacy of Mangifera indica Kernel Extract as Root Canal Irrigant in Primary Molar: An In Vitro Study.

Endodontic therapy aims to disinfect the entire root canal system. Extracts from the kernel of Mangifera indica has the potential to be a novel root canal irrigant that has yet to be studied. Hence, the present study evaluated the antimicrobial, and smear layer removal efficacy of the M. indica kernel extract as a root canal irrigant in primary molars. Methanolic extract of M. indica was prepared using the standard method. The antimicrobial efficacy of M. indica kernel extract was determined by agar diffusion method with 3% sodium hypochlorite and distilled water as controls, and the smear layer removal efficacy was assessed under the SEM after processing the root samples with different concentrations of M. indica kernel extract with 17% EDTA and distilled water as positive and negative controls, respectively. A statistically significant antimicrobial efficacy was observed with the largest mean zone of inhibition recorded with 50 μl of M. indica kernel extract at 24 hr of incubation period, when compared to sodium hypochlorite as a root canal irrigant against Enterococcus faecalis using agar diffusion method at MIC value of 0.625 mg/ml. The smear layer removal efficacy of the M. indica kernel extract was not satisfactory, when compared with EDTA as a root canal irrigant in primary molars and observed under SEM. In contrast, a complete smear layer removal was observed with 17% EDTA solution. M. indica kernel extract has an enhanced antimicrobial efficacy but poor smear layer removal efficacy when used as a root canal irrigant.

Comparative evaluation of the effect of ultrasonic and rotary agitation of herbal irrigating solutions on smear layer: A SEM study.

Instrumentation and irrigation balance helps in effective removal of endodontic microbes housing inside the smear layer. This study aimed to (1) evaluate whether activation of the irrigating solutions with two different systems during the final irrigation step can lead to smear layer formation in the middle and apical third of the root canal and (2) evaluate and compare the smear layer removal ability of the aqueous extracts of Emblica officinalis and Morinda citrifolia. A total of 72 single-rooted teeth were prepared up to F4 ProTaper. The specimens were assigned into eight groups of nine teeth each, according to the final irrigant and activation techniques. Further, the teeth were evaluated under SEM for endodontic smear layer at the middle and apical third. Inferential statistics included Pearson's Chi-square. Level of significance was set at 0.05 at 95% confidence level. Ultrasonic activation system showed significant (P = 0.000) amount of smear layer compared to XP-Endo Finisher file. A significant difference (P = 0.00) in the smear layer removal was observed when 6% M. citrifolia was activated with XP-Endo Finisher file both in the middle and apical third. Within the limitations of this in vitro study, it can be concluded that smear layer formation was noted with ultrasonic and XP-Endo Finisher file when saline was used as an irrigant. 6% M. citrifolia when activated with XP-Endo Finisher file showed best results among all other experimental groups.

Effect of collagen cross-linking agents on the depth of penetration of bioceramic sealer and release of hydroxyproline: An in vitro study.

During endodontic treatment, sealers seal off dentinal tubules and prevent microbial attack. Bioceramic sealers have excellent bioactivity, but its high alkalinity is found to have detrimental effects on radicular collagen. Collagen cross linkers have the ability to chemically modify collagen and can prevent the detrimental effects of the sealer. This research was aimed to assess the effect of collagen cross-linking agents on the integrity of radicular collagen matrix and depth of penetration of sealer. Mandibular premolars (n = 48) were taken. Teeth were decoronated; canals were prepared till ProTaper size F2 and were irrigated with 5 mL of 2.5% NaOCl, followed by 3 mL of 17% ethylenediaminetetraacetic acid between instrumentation and finally rinsed with saline following which teeth were divided into three groups based on the surface treatments: Group 1: 6.5% proanthocyanin (PA), Group 2: chlorhexidine (CHX), and Group 3: saline. Teeth were obturated using gutta-percha and bioceramic sealer and stored in artificial saliva. Hydroxyproline (HYP) release was assessed after 14 and 21 days using spectrophotometer. Sealer penetration was assessed using the scanning electron microscope. Wilcoxon signed-rank test and Kruskal-Wallis test for release of HYP and paired t-test and ANOVA for sealer penetration were performed. Significantly lower release of HYP was seen in proanthocyanin-treated group. Sealer penetration was better for both the proanthocyanin- and CHX-treated groups when compared to saline. Surface treatment with collagen cross-linkers caused a decrease in the amount of HYP released, indicating lesser degradation of collagen. Sealer penetration was better due to the removal of smear layer following the surface treatments.

Comparison of Easydo Activator, ultrasonic and needle irrigation techniques on sealer penetration and smear layer removal in vitro

The effects of Easydo Activator (EA), a new sonic irrigation system, on sealer penetration at the root apex were compared to needle irrigation (NI) and passive ultrasonic irrigation (PUI) in this study. Forty-two single-rooted teeth were prepared and randomly divided into three groups (n = 14): group 1: NI; group 2: PUI; and group 3: EA. A solution of 3% sodium hypochlorite (NaOCl) was used for irrigation. Nine teeth in each group were filled with AH Plus sealer mixed with CY5 fluorescent dye and a single gutta-percha cone. The sealer penetration area, maximum penetration depth and percentage of sealer penetration at 5 mm and 1 mm from the apex were analyzed by confocal laser scanning microscopy (CLSM). The remaining 5 teeth in each group were subjected to test smear layer scores by scanning electron microscopy (SEM). The CLSM evaluation showed that increases in the area, depth and percentage of sealer penetration were detected at 1 and 5 mm from the root apex in the PUI group compared with the NI group, and greater increases were observed in the EA group (P < 0.05). The SEM experiment showed that the lowest scores for the smear layer and debris removal were achieved by the EA group when compared with the PUI and NI groups (P < 0.05). In conclusion, EA was superior to PUI and NI regarding sealer penetration at the root apex during endodontic treatment, and it could provide a new technical idea for clinical root canal therapy.