Passive Ultrasonic Irrigation Research Articles

The effect of different irrigation activation methods on the penetration of the irrigation solution into the dentinal tubules in teeth with calcium hydroxide applied and oval-shaped canals: Confocal laser scanning microscope analysis.

This study aimed to evaluate the efficacy of different irrigation techniques including standard needle irrigation (SNI), passive ultrasonic irrigation (PUI), EndoActivator (EA), XP-Endo Finisher (XPF), photon-induced photoacoustic streaming (PIPS), and shock wave enhanced emission photo-acoustic streaming (SWEEPS) systems on the penetration of irrigation solutions into dentinal tubules in teeth with calcium hydroxide (CH) applied and oval-shaped canals by confocal laser scanning microscope (CLSM). Ninety mandibular incisor teeth with oval-shaped canals were included in this study. After the preparation of teeth using Resiproc Blue R25 (VDW, Munich, Germany) canals were filled with a paste based on CH. The teeth were stored in 100% humidity at a temperature of 37°C for 14 days. According to the irrigation activation systems, the teeth were divided into six groups (n = 15); SNI, PUI, EA, XPF, PIPS, and SWEEPS. In each group, 3 irrigation/activation cycles of 20 s of irrigation and 20 s of activation were performed with the relevant activation method. The root canals were filled with fluorescein sodium (Sigma, Alldrich Co., St. Louis, MO, USA) and activated with the relevant activation method for 30 s. Specimens were sectioned horizontally to 1 ± 0.1 mm at 2, 5, and 8 mm from the apex and then examined under the CLSM. Maximum penetration depth, maximum penetration area and penetration percentage were measured by using Image J software. Data were analyzed using a two-way analysis of variance (ANOVA) and posthoc Tukey tests (p = .05). No difference was found between the activation systems in terms of maximum penetration depth and maximum penetration area of irrigation solutions in the apical section (p > .05). The penetration percentage of irrigation solutions was higher in PUI and PIPS compared with EA and XPF at the apical section (p < .05). No difference was found between SNI, PUI, PIPS, and SWEEPS in terms of the penetration percentage of irrigation solutions in all sections (p > .05). The penetration percentage of irrigation solutions was higher in the middle and coronal sections compared to the apical section in EA and XPF (p < .05). Tubule penetration of irrigation solutions in SNI was similar between sections. The Tubule penetration area of irrigation solutions in PUI, EA, XPF, PIPS, and SWEEPS was lower in the apical section than in the middle and coronal sections. RESEARCH HIGHLIGHTS: The tubule penetration depth and area of the irrigation solutions were similar between the activation systems tested in the apical sections. The Tubule penetration area of irrigation solutions in middle and coronal sections was higher in PUI and PIPS than in SNI.

Assessment of different irrigation techniques on the penetration depth of different sealers into dentinal tubules by confocal laser scanning microscope: An in vitro comparative study

Abstract Background: The effective disinfection of the entire root canal system aids in the penetration of irrigants into the dentinal tubules further improving sealer penetration and achieving a three-dimensional seal in endodontically treated teeth. Various final irrigation techniques can be employed to achieve this goal. Therefore, this study intended to assess and compare the efficacy of three final irrigation techniques on the depth of penetration of two root canal sealers into dentinal tubules using confocal laser scanning microscope (CLSM). Methods: Forty-eight single-rooted mandibular premolars were selected and decoronated to a length of 12 mm. All the samples were prepared using ProTaper Gold rotary files and divided into three groups: Group 1 – Conventional syringe irrigation (CSI), Group 2 – passive ultrasonic irrigation (PUI), and Group 3 – Pro-agitator tip system (PATS). Each group was divided into two subgroups: Subgroup A – AH Plus and Subgroup B – GuttaFlow Bioseal (GFB). Then, sealers were mixed with 0.1% rhodamine B dye and the samples were obturated. All the samples were sectioned at 2 mm and 5 mm from the apex and visualized under confocal laser scanning microscope (CLSM) (10×) for maximum mean penetration depth and percentage of sealer penetration. Statistical analysis was done using the independent t-test and one-way analysis of variance test, followed by Tukey’s Post hoc analysis. Results: PUI performed better in the apical third, whereas PUI and PATS showed comparable results in the middle third for both depth and percentage of sealer penetration. Among the two sealers, GFB performed better than AH Plus in both the apical and middle third. These values were statistically significant. (P &lt; 0.05). Conclusion: Final irrigation activation with PUI or PATS can significantly improve sealer penetration. The average depth of penetration of GFB both at the middle and apical third of the root was significantly superior to AH Plus.

Antimicrobial efficacy of two commercially available herbal products with and without ultrasonic activation in primary endodontic infections: A randomized clinical trial.

Effective irrigation is crucial for successful endodontic treatment. Traditional irrigants like sodium hypochlorite (NaOCl) have been widely used, but there is a growing interest in exploring natural alternatives for their potential antimicrobial properties. The study aims to compare the antimicrobial efficacy of Neem, Bitter Gourd, and NaOCl, with and without ultrasonic activation in managing primary endodontic infections. Ninety patients were randomly assigned six groups (n = 15) Group 1: NaOCl, Group 2: NaOCl with passive ultrasonic irrigation (PUI), Group 3: Neem juice, Group 4: Neem juice with PUI, Group 5: Bitter gourd juice, and Group 6: Bitter gourd juice with PUI. Bacteriological samples were collected before (S1) and after (S2) shaping, plated on brain heart infusion agar, and colony counting was done after 24 h. Shapiro-Wilk test, one-way ANOVA, post hoc Tukey analysis, and paired t-test. All the groups demonstrated a significant reduction in bacterial count. Groups with PUI (2, 4, 6) demonstrated higher mean bacterial reduction than their counterparts without PUI (1, 3, 5). Neem and Bitter gourd juices, particularly when used with PUI, demonstrated antimicrobial efficacy comparable to NaOCl with PUI.

Root canal dentin wear during final irrigation in endodontic retreatment with passive ultrasonic irrigation and easy clean instruments.

Complementary procedures have been proposed to improve the endodontic retreatments. The aim of this study was to evaluate, by microcomputed tomography (micro-CT), the dentin wear caused by passive ultrasonic irrigation (PUI) and easy clean (EC) instruments, when used for the final removal of filling material during endodontic retreatment. Thirty-six mesial roots of the lower first molars were divided into four groups (n = 9), according to the final irrigation and sealer: PUI/AH Plus, EC/AH Plus, PUI/Total Fill (TF), and EC/TF. Canal volume was evaluated, both before and after the final irrigation, by micro-CT analysis. The Kruskal-Wallis test was used to compare the volumes among groups and the paired Wilcoxon test was used to compare the volume values before and after the final irrigation within each group. Both complementary cleaning procedures promoted dentin wear that was observed only when the volume was analyzed for each third of the root canal. In the apical third, both instruments showed significant wear, where the use of the EC instrument resulted in greater wear than the PUI, in teeth filled with both AH Plus and TF BC Sealers (P < 0.05). Both complementary cleaning procedures promoted dentin wear and must be used cautiously.

In vitro efficacy of Er:YAG laser-activated irrigation versus passive ultrasonic irrigation and sonic-powered irrigation for treating multispecies biofilms in artificial grooves and dentinal tubules: an SEM and CLSM study

BackgroundMultispecies biofilms located in the anatomical intricacies of the root canal system remain the greatest challenge in root canal disinfection. The efficacy of Er:YAG laser-activated irrigation techniques for treating multispecies biofilms in these hard-to-reach areas has not been proved. The objective of this laboratory study was to evaluate the effectiveness of two Er:YAG laser-activated irrigation techniques, namely, photon-induced photoacoustic streaming (PIPS) and shock wave-enhanced emission photoacoustic streaming (SWEEPS), in treating multispecies biofilms within apical artificial grooves and dentinal tubules, in comparison with conventional needle irrigation (CNI), passive ultrasonic irrigation (PUI), and sonic-powered irrigation (EDDY). Two types of multispecies root canal biofilm models were established in combination with two assessment methods using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) with the aim to obtain more meaningful results.MethodsNinety extracted human single-rooted premolars were chosen for two multispecies biofilm models. Each tooth was longitudinally split into two halves. In the first model, a deep narrow groove was created in the apical segment of the canal wall. After cultivating a mixed bacterial biofilm for 4 weeks, the split halves were reassembled and subjected to five irrigation techniques: CNI, PUI, EDD, PIPS, and SWEEPS. The residual biofilms inside and outside the groove in Model 1 were analyzed using SEM. For Model 2, the specimens were split longitudinally once more to evaluate the percentage of killed bacteria in the dentinal tubules across different canal sections (apical, middle, and coronal thirds) using CLSM. One-way analysis of variance and post hoc multiple comparisons were used to assess the antibiofilm efficacy of the 5 irrigation techniques.ResultsRobust biofilm growth was observed in all negative controls after 4 weeks. In Model 1, within each group, significantly fewer bacteria remained outside the groove than inside the groove (P < 0.05). SWEEPS, PIPS and EDDY had significantly greater biofilm removal efficacy than CNI and PUI, both from the outside and inside the groove (P < 0.05). Although SWEEPS was more effective than both PIPS and EDDY at removing biofilms inside the groove (P < 0.05), there were no significant differences among these methods outside the groove (P > 0.05). In Model 2, SWEEPS and EDDY exhibited superior bacterial killing efficacy within the dentinal tubules, followed by PIPS, PUI, and CNI (P < 0.05).ConclusionEr:YAG laser-activated irrigation techniques, along with EDDY, demonstrated significant antibiofilm efficacy in apical artificial grooves and dentinal tubules, areas that are typically challenging to access.

Cleaning and disinfection of the root canal system provided by four active supplementary irrigation methods

This in vitro study evaluated the bacterial reduction provided by the EndoActivator (EA), Easy Clean (EC), passive ultrasonic irrigation (PUI), and XP-Endo Finisher. Eight-four mesial roots of mandibular first molars were instrumented, inoculated with Enterococcus faecalis, and divided into four groups (n. 20). Bacterial reduction in the main canals and dentinal tubules were respectively determined by MTT assays and Live/Dead BackLight technique through confocal laser scanning microscopy (CLSM) at 50, 100, and 150 µm in-depth (n. 10 per group). Statistical analyses were conducted following a significance level of 95% (P < 0.05). A significant statistical difference was just identified between XPF and EC in the main canals. In the dentinal tubules from the main root canals, at 100 and 150 µm in-depths, significant statistical differences were only observed between XPF and EC (P = 0.027) for the former and between XPF and EC (P = 0.011) and XPF and PUI (P = 0.021) for the latter. In the dentinal tubules from the isthmus, at 100 µm in-depth, statistically relevant differences did occur between XPF and EC (P = 0.038) and EC and EA (P = 0.029). At 150 µm in-depth, these differences were only significant by comparing XPF and PUI (P = 0.025) and XPF and EC (P = 0.036). Although no irrigation method could thoroughly disinfect the RCS, bacterial reduction indexes were generally better after using XPF.

Comparative evaluation of ethanol versus citric acid in removal of oil-based calcium hydroxide from the apical third of root canal system.

To evaluate the effectiveness of ethanol compared to citric acid in the removal of oil-based calcium hydroxide from the apical third of the root canal system using passive ultrasonic irrigation. The in vitro study was conducted from September to October 2021 at the dental clinics of the Aga Khan University Hospital, Karachi, and comprised single-rooted teeth that were selected from institutional bank of extracted teeth. They were randomly divided into group A having 70% ethanol + passive ultrasonic irrigation, group B 10% citric acid + passive ultrasonic irrigation, group C positive controls and group D negative controls. The specimens were sectioned at 1mm and 3mm from the apex and examined under a dental operating microscope. A single examiner scored the specimens on two different occasions. Data was analysed using SPSS 25. Of the 90 teeth, there were 40(44.4%) in each of the 2 experimental groups and 5(5.5%) in each of the 2 control groups. At 3mm apical sections, ethanol was significantly more effective in the removal of oil-based calcium hydroxide (p=0.01). However, at 1mm from the apex, there was no significant difference between the experimental groups (p=0.064). Intragroup comparison showed that for groups A and B, residual medicament at 1mm sections was significantly greater than at 3mm sections (p<0.001, p=0.003). Neither irrigant showed complete removal at 1mm and 3mm from the apex. However, at 3mm apical sections, 70% ethanol was significantly more effective compared to 10% citric acid.

Comparative evaluation of antifungal activity of Sodium Hypochlorite, Calcium Hypochlorite and modified Salt Solution associated with passive ultrasonic irrigation against Candida albicans - An In-Vitro study.

The study evaluated the antifungal activity of sodium hypochlorite (NaOCl), calcium hypochlorite (Ca(OCl)2), and modified salt solution (MSS) assisted with passive ultrasonic irrigation against Candida albicans. One hundred and thirty-six single-rooted premolars were decoronated and enlarged up to a file #45, autoclaved, inoculated with C. albicans, and incubated for 72 h. The samples were randomly distributed into eight groups (n = 17) according to the protocol for decontamination G1: No treatment, G2: Distilled water (DW), G3: 2.5% NaOCl, G4: 2.5% NaOCl + ultrasonic activation (US), G5: 2.5% Ca(OCl)2, G6: 2.5% Ca(OCl)2 + US, G7: MSS, G8: MSS + US. Microbiological testing (Colony forming Unit [CFU] counting) was performed before and after the treatment. Data were subjected to the one-way analysis of variance followed by the Tukey's post hoc test (P < 0.05). Groups 1 and 2 showed the highest mean contamination (5.41 and 4.31 log10 CFU/mL, respectively), which was statistically different from all the other groups (P < 0.001). G4 showed the lowest mean contamination (0.24 log10 CFU/mL) with statistically significant value (P < 0.001). 2.5% NaOCl with ultrasonic activation can aid in significant fungal reduction. Ultrasonic activation of 2.5% NaOCl, 2.5% Ca(OCl)2, and MSS was also found to have improved antifungal activity against C. albicans.

Efficacy of Different Irrigation Activation Techniques on Dentinal Tubule Penetration of the Novel AH-Plus Bioceramic Sealer

This study aimed to assess the penetration of AH-Plus (AHP) and AH-Plus Bioceramic (AHPB) sealers into dentinal tubules subsequent to different irrigation activation protocols. One hundred fifty teeth were divided into five groups according to the final irrigation protocol: conventional syringe irrigation (CSI), EndoActivator (EA), passive ultrasonic irrigation (PUI), Er,Cr:YSGG laser, and SWEEPS. Then, the teeth were divided into two subgroups (n = 15) according to the canal sealer type. The maximum penetration depth (MPD) point and percentage of the sealer were evaluated using confocal laser scanning microscopy. Then, the data were statistically analyzed. The highest MPD values were observed in the SWEEPS groups, while the lowest value was in the CSI groups. Considering the effect of the sealer type and irrigation protocol interaction, there was a significant difference between the Er,Cr:YSGG laser, and EA groups for the AHPB sealer (p &lt; 0.05), while it was insignificant for the AHP sealer (p &gt; 0.05). The AHP and AHPB sealers statistically presented similar penetration properties. Laser-activated irrigation presented a higher sealer penetration compared to the other techniques.

Comparison of the removal of intracanal medicaments used in regenerative endodontics from root canal system using needle, ultrasonic, sonic, and laser-activated irrigation systems

This study aimed to compare the syringe-needle irrigation (SNI), passive ultrasonic irrigation (PUI), EDDY, and shock wave–enhanced emission photoacoustic streaming (SWEEPS) techniques regarding calcium hydroxide and double antibiotic paste removal from the root canal in regenerative endodontic treatments. Eighty single-rooted human teeth were decoronated and enlarged up to #100 to stimulate the immature tooth model. Root canals were irrigated with 1.5% sodium hypochlorite followed by saline solution according to the regenerative endodontic treatment protocol. Dressed teeth were divided into 2 main groups regarding the used intracanal medicaments. Calcium hydroxide and double antibiotic paste were introduced to the canals, and teeth were stored for 3 weeks. Each medicament group was divided into 4 subgroups according to the activation techniques. Medicaments were removed using a 17% EDTA solution. Teeth were split longitudinally into two parts. The remaining medicaments were evaluated under a stereo microscope with a scoring system. Data were analyzed with the Kruskal-Wallis and Mann-Whitney U tests. Regardless of the used irrigation activation systems, there was no statistically significant difference between the removal of the CH and DAP from the root canal (P>0.05). While SWEEPS had the highest ability regarding the removal of intracanal medicaments, syringe-needle irrigation had the lowest (P<0.05). There was no statistically significant difference between PUI and EDDY (P>0.05). Complete removal of intracanal medicaments could not be achieved with any techniques. SWEEPS technology was more effective in removing intracanal medicaments in regenerative endodontic treatments compared to the sonic and ultrasonic irrigation activation systems.

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.

Can Heated Distilled Water Effectively Prevent Precipitate Formation between NaOCl and CHX?

The present study aimed to investigate the capacity of different irrigation protocols using heated distilled water at 65°C (HDW), in preventing the formation of the brown-orange precipitate observed after the interaction between sodium hypochlorite (NaOCl) and chlorhexidine (CHX). Forty human canines were selected, prepared, and cleaved in two halves. Images of delimited areas in each root canal thirds were obtained through a stereomicroscope (16x and 40x). After reassembly, the teeth were distributed into four groups (n = 10) according to the final irrigation protocol: G1 (no HDW): EDTA + NaOCl + CHX with conventional irrigation (CI); G2 (HDW + CI): EDTA with passive ultrasonic irrigation (PUI) + NaOCl (PUI) + HDW (CI) + CHX (PUI); G3 (HDW + PUI): EDTA + NaOCl + HDW + CHX with PUI; G4 (HDW + CUI): EDTA (PUI) + NaOCl (PUI) + HDW with continuous ultrasonic irrigation (CUI) + CHX (PUI). After irrigation, the teeth were re-separated and images of the same delimited areas were obtained again. Scores were assigned according to the amount of precipitate observed, comparing the initial and final images. The data were submitted to Kruskal-Wallis, Dunn and Friedman statistical tests (α = 5%). G1(no HDW) showed the highest scores in the analysis between groups (p < 0.001), with a greater amount of precipitate in the cervical and medium thirds (p < 0.001). The thirds of the other experimental groups did not differ from each other (p > 0.05). The intermediate irrigation with heated distilled water at 65°C prevented the formation of brown-orange precipitate, regardless of the use of ultrasonic activation (PUI or CUI).

The efficacy of various irrigation techniques on the removal of double antibiotic paste from simulated immature roots and the amount of apically extruded debris

ObjectiveThis study evaluated the effect of the XP-Endo Finisher (XPF), passive ultrasonic irrigation (PUI) and conventional irrigation using side-vented needle (SVN) on the amount of apically extruded debris and canal cleanliness following the removal of double antibiotic paste (DAP) from immature root canal models.Material and methodsForty-eight extracted mandibular premolars were drilled using peeso drills to simulate immature apices. The canals were filled with DAP and were randomly assigned into 3 groups according to the DAP removal method: XPF, PUI, and SVN (n = 16). The amount of extruded debris was assessed with an analytical balance then roots were split longitudinally and imaged using stereomicroscope to evaluate the residual medicament. Data were statistically analyzed using Kruskal-Wallis and Dunn’s test. Spearman’s correlation coefficient was used to determine significant correlation between extruded debris and the residual DAP scores.ResultsThere was no significant difference between debris extrusion values for all groups (P value 0.237). For canal cleanliness, the amount of remaining DAP was significantly lower in the XPF and PUI compared to SVN (P value < 0.001). A non-significant positive (direct) correlation was found between the amounts of apically extruded debris and residual DAP scores (P value 0.087).ConclusionXPF and PUI were associated with better canal cleanliness during removal of DAP, no difference could be found between the three irrigation techniques regarding the debris extrusion.

Influence of Passive Ultrasonic Irrigation of the Photosensitizer Used in Photodynamic Therapy on Microbial Reduction in the Root Canal System: An in Vitro Study.

The success of endodontic treatment is based on microbial reduction promoted by the interaction of chemical and mechanical procedures. Photodynamic therapy (PDT) is used as an adjunct to conventional treatment, with significant microbial reduction. This study aimed to evaluate the influence of passive ultrasonic irrigation (PUI) of the photosensitizer (PS) used in PDT on microbial reduction in the root canal system. Forty-five mesiobuccal root canals from extracted human mandibular molars that were inoculated with standard strains of Enterococcus faecalis, Candida albicans, and Streptococcus mutans for 21 days were selected. The root canals were prepared using the ProTaper Next system and randomly divided into 3 groups (n=15): 1) PDT: PDT alone; 2) PUI+PDT: PUI followed by PDT; and 3) PUI/PS+PDT: PUI of the PS followed by PDT. Microbiological samples were collected from the canals before and after using the protocols described above. The data were analyzed by analysis of variance (Tukey's test) at a significance level of 5%. Microbial counts before PDT, PUI+PDT, and PUI/PS+PDT did not differ significantly (P>0.05), showing methodological standardization in the microbial contamination of the root canal system. There was a significant reduction in microbial counts after PDT (61.05%), PUI+PDT (65.04%), and PUI/PS+PDT (68.58%) (P<0.01), but with no statistically significant difference between the three groups (P>0.05). Based on the present findings, it was concluded that the combination of PUI with PDT or PS activation did not influence microbial reduction achieved by PDT alone.

Filling Material Bond Strength to Dentin Is Positively Influenced by the Agitation of Endodontic Final Irrigating Solutions.

The final step of irrigation has been considered to of increase the bonding strength of filling material to dentin. This study investigated the impact of three final-step irrigation methods on the endodontic sealer bond strength to dentin by using a micro push-out test. Palatal roots of human maxillary molars were cleaned and shaped and randomly divided in six groups (n=15) according to the final-step irrigation method and the type of root canal sealer used. The solutions used for the final-step irrigation were 17% ethylenediaminetetraacetic acid and 2.5% sodium hypochlorite, which underwent three methods: 1) syringe-needle irrigation/conventional, 2) passive ultrasonic irrigation, and 3) XP-endo Finisher agitation. The root canal sealers used were: EndoSequence BC Sealer, and AH-Plus sealer. Roots were obturated with the single cone technique and then, cross-sectioned in 2-mm-thick slices (3 slices from each root). Push-out test was performed on the sliced specimens (cervical, middle, and apical thirds) with a universal testing machine. Bond strength values were recorded in megapascal (MPa). Subsequently, each specimen was longitudinally split to verify the type of failure. Data analysis was performed using Johnson transformation, three-way analysis of variance, Tukey's post-hoc tests, and the partial Eta squared test. There were significant differences in bond strength between the sealers [AH: 4.46±2.24 and BC: 3.47±2.19 MPa (P<0.001)]; between final-step irrigation methods [passive ultrasonic irrigation: 4.52±2.25, XP-endo Finisher: 3.93±3.93 and syringe-needle irrigation/conventional: 3.37±2.51 MPa (P<0.001)], and between the root canal thirds represented by the sliced specimens [cervical: 5.45±2.39, middle: 4.14±1.99 and apical: 2.30±1.30 MPa (P<0.001)]. The interaction between the variables had no significance (P>0.05). Agitation of the final irrigating solution may improve the bonding of the sealer to canal walls. AH-Plus sealer had the highest bond strength. The bond strength reduced significantly towards the apical third.

Effect of different irrigation activation systems using continuous chelating irrigation protocol on the removal of smear layer in the apical third of root canals: An in vitro scanning electron microscope study

Aim: Continuous chelation is a novel irrigation regimen popular as a single solution for irrigation of the root canal system during root canal therapy, especially for the removal of the smear layer. This study aimed to compare the effectiveness of three different irrigation activation systems in removing the smear layer from the apical third in single-rooted mandibular premolars using a scanning electron microscope (SEM). Methods: Fifty-six extracted single-rooted mandibular premolars were decoronated, and canals prepared till #30/0.09, with Chloroquick (3% NaOCl + 9% HEBP) as the working solution. Teeth were randomly divided into four groups based on the final irrigant activation protocol; Group A - (control group) conventional syringe irrigation with a 30-gauge single-side vented needle. Group B - (passive ultrasonic irrigation method) passive ultrasonic irrigation (PUI) with #20-Irrisafe ultrasonic files activated for 1 min. Group C - (sonic activation) EndoActivator system using the yellow tip (#20/0.04) activated for 1 min. Group D - Tornado Disinfection Kit using GF-brush for 20–30 s as per manufacturer’s instructions. The canals were dried, samples were hemi-sectioned, and the amount of remaining smear layer was scored according to the Tabrizizadeh criteria (2015) with SEM images at ×2500 by two blinded operators. The collected data were analyzed statistically using the Chi-square test (P &lt; 0.05). Results: The results showed statistically significant differences in terms of smear removal among the groups (P &lt; 0.05) with the Gentlefile group performing better, followed by PUI, EndoActivator, and the conventional group. Conclusion: Within the limitations of the study, continuous chelation with Gentlefile activation could be a viable and efficient protocol for the removal of the smear layer from the apical third of root canals.

Analysis of the depth of penetration of an epoxy resin-based sealer following a final rinse of irrigants and use of activation systems: An in vitro study.

The objective of the study was to compare and evaluate the depth of penetration of an epoxy resin-based sealer following a final rinse of 17% ethylenediaminetetraacetic acid (EDTA) and 18% 1-hydroxyethylidene 1, 1-diphosphonate (HEDP), with diode laser and passive ultrasonic activation (PUI): an in vitro confocal laser scanning microscopy study. Fifty-two extracted human mandibular premolar teeth with single root and single canal were selected. They were disinfected in 0.1% thymol solution, cleaned of calculus and soft tissues, and stored in 0.1% thymol solution till use. All teeth were radiographed and selected as per the inclusion and exclusion criteria. The teeth were decoronated using a diamond disk under copious water spray to acquire a standardized root length of 14 mm. Working length was established by inserting a size 10-K file into each root canal until it is visible at the apical foramen and by subtracting 1 mm from the recorded length. Instrumentation of the root canal was done till master apical file size of F3 using ProTaper universal, rotary instruments. The canals were irrigated with 2 mL of 3% sodium hypochlorite between successive files. Teeth were randomly divided into four subgroups n = 12 according to the intervention. Passive ultrasonic irrigation and diode laser were used to activate the irrigants. Final irrigation was performed with distilled water. These specimens were examined using confocal laser scanning microscope (OLYMPUS FLUOVIEW FV 3000) for dentinal tubule penetration of the sealer. Two-way ANOVA test and Tukey's multiple post hoc test were used for statistical analysis. Highly significant difference was seen between the groups with EDTA and HEDP, with HEDP demonstrating the highest penetration. Among the activation techniques used in this study, PUI showed the highest penetration of the sealer. The least penetration was seen with diode laser activation and EDTA. The irrigation activation techniques significantly influence the penetration of sealer into root dentinal tubules. When penetration of sealer with different irrigation techniques and irrigants was evaluated, significant greater level of sealer penetration was attained with PUI activation of HEDP.

Passive ultrasonic irrigation on postoperative pain after endodontic treatment: a randomized clinical trial

Objective:This randomized clinical trial evaluated the effect of passive ultrasonic irrigation (PUI) protocol employed during endodontic treatment on the incidence of postoperative pain. Methods: Sixty adult patients with non-vital asymptomatic premolar and molars were included. The treatments were performed using ProTaper Universal instruments with working length set 1.0 mm short of the apical foramen. The patients were randomly divided to receive one of the following two final cleansing protocols (n = 30): PUI - the canals were rinsed with 2.5% NaOCl, 17% EDTA, and 1.0% NaOCl sequentially, with 3 cycles of 20 seconds in each irrigation solution, under ultrasonic agitation; Control (CON) - similar final irrigation protocol was employed without any agitation. To evaluate postoperative pain, a numerical rating scale was applied every 24 hours until the fifth day. Data were statically analyzed with Pearson's Chi-square, Friedman's and ANOVA tests with 5% of significance. Results: There were no significant differences in any of the periods (P=0.46). The great majority of patients in both groups showed no pain symptoms. No patient reported severe pain (≥ 7), with moderate pain occurring in only 2 patients in the CON group (7.4%) and 4 patients in the PUI group (16.7%), exclusively in the first 24 hours. Conclusions: The use of passive ultrasonic irrigation protocol did not influence the occurrence of postoperative pain in patients submitted to endodontic treatment.

Removal of Calcium Hydroxide Medicament from the Apical Root Canal using Different Irrigation Methodologies: A Scanning Electron Microscopy Study

Introduction: To evaluate the efficiency of different irrigants and agitation techniques in the removal of calcium hydroxide Ca(OH)2 medicament from the root canal walls. Material and Methods: N=84 mandibular premolars were selected for this study. The root canal of these 84 premolars was cleaned up using the ProTaper rotary system up to the file size F3 and then filled with Ca(OH)2 medicament. For seven days, the root samples were maintained at 37o C and 100% relative humidity. The sample was divided into four groups (n=20 each) using random allocation employing different agitation methods: Group 1- MAF - Master Apical File, Group 2 - PUI - Passive Ultrasonic Irrigation, Group 3 - CB - Canal Brush, and Group 4 - FF - F File. Each group was further subdivided into two subgroups based on the specific chelating agent employed: (a) 10% Citric Acid and (b) 17% EDTA. Longitudinal bisection was performed in the apical (lower) third of the root structure. Further, an assessment was done using SEM (scanning electron microscopy) to study the elimination of Ca(OH)2. Kruskal- Wallis and Mann-Whitney tests were used for statistical analysis. Results: Groups 1 (MAF) and Group 3 (CB) showed a significant statistical difference (p&lt;0.05) when compared to Group 2 (PUI) and Group 4 (FF). An insignificant difference (p&gt;0.05) was seen between the performance of chelating agents (10% Citric Acid and 17% EDTA). Conclusion: Irrespective of the specific chelating agents employed, both the PUI (Passive Ultrasonic Irrigation) and FF (F File) agitation techniques exhibited superior efficacy in the removal of Ca(OH)2 medicament from the apical (lower) third when compared to the CB (Canal Brush) and MAF (Master Apical File) methods.

A Comparative Evaluation of the Cleaning Efficacy of Five Different Root Canal Irrigation Devices: A Histological Study.

This study is aimed to evaluate the cleaning efficacy of five different irrigation systems as SonicMax, RinsEndo, EndoVac, passive ultrasonic irrigation (PUI), and manual needle irrigation (MNI) to histologically evaluate the presence of organic structures and the penetration of irrigation solution. Forty-two single-rooted, extracted human mandibular premolars were used in the study. Each tooth was decoronated at the cementoenamel junction and the root canals were instrumented using ProTaper rotary instruments in a crown-down manner. The specimens were randomly divided into five experimental groups (n = 7) Group (1) SonicMax, group (2) RinsEndo,group (3) EndoVac, group (4) PUI, group (5) MNI, and the control groups (n = 7). Each system used 2.5% sodium hypochlorite (NaOCl), 17% ethylenediamine tetraacetic acid (EDTA), and 2.5% NaOCl, respectively, in the experimental groups. The control group did not receive any final irrigation.The measurements were analyzed by employing two-way analysis of variance multivariate results to show significant differences between the length of the dentin tubules in the apical, middle, and coronal of the six groups. The post-hoc test was used when groups were compared by pairs. The results of this study indicate that among the five groups, the RinsEndo and EndoVac were found to be most effective in the cleaning of root canals. The RinsEndo shows highly significant results in the cleaning efficiency of the coronal and middle parts compared with the other groups. The cleaning efficiency in the apical area was the same for RinsEndo and EndoVac. The result of our study indicates that RinsEndo and EndoVac may be more effective in clinical practice.