Syringe Irrigation Research Articles

Effectiveness of different irrigation techniques on smear layer removal in apical thirds of mesial root canals of permanent mandibular first molar: A scanning electron microscopic study.

Aim:The aim of this study was to compare smear layer removal after final irrigant activation with sonic irrigation (SI), manual dynamic agitation (MDA), passive ultrasonic irrigation (PUI), and conventional syringe irrigation (CI).Materials and Methods:Forty mesial canals of mandibular first molars (mesial roots) were cleaned and shaped by using ProTaper system to size F1 and sodium hypochlorite 3% and 17% ethylenediaminetetraacetic acid. The specimens were divided into 4 equal groups (n = 10) according to the final irrigation activation technique: Group 1, PUI; group 2, manual dynamic activation (MDA); group 3, SI; and group 4, control group (simple irrigation). Samples were split longitudinally and examined under scanning electron microscope for smear layer presence.Results:Control groups had the highest smear scores, which showed the statistically significant highest mean score at P < 0.05. This was followed by ultrasonic, MDA, and finally sonic, with no significant differences between them.Conclusions:Final irrigant activation with sonic and MDA resulted in the better removal of the smear layer than with CI.

Antibiofilm activity of three irrigation protocols activated by ultrasonic, diode laser or Er:YAG laser in vitro.

To investigate the impact of three irrigation protocols, activated by three different methods, on mature biofilms of Enterococcus faecalis in vitro. Root canals in 280 single-rooted teeth were instrumented using a rotary Ni-Ti system. Biofilms of E. faecalis were generated based on a previously established protocol. Samples were randomly divided into three experimental (n = 80) and one control (n = 40) group based on the irrigation protocol employed: group 1 (NaOCl + Etidronic acid), 1 : 1 mixture of 6% NaOCl and 18% etidronic acid; group 2 (NaOCl-EDTA), 3% NaOCl followed by 17% EDTA; group 3 (NaOCl-EDTA-NaOCl), 3% NaOCl followed by 17% EDTA and a final flush of 3% NaOCl. Saline served as the control. Samples were further divided into four subgroups (n = 20) based on the activation method: subgroup A, no activation; subgroup B, ultrasonic activation; group C, diode laser; group D, Er:YAG laser. Confocal laser scanning microscopy was used to assess bacterial viability in situ. Root dentine powder was obtained for determining the colony-forming units (CFU mL(-1) ). Data were analysed by appropriate statistical analyses with P = 0.05. All experimental irrigation protocols caused complete destruction of the biofilm in the root canal lumen. Within the dentinal tubules, all groups had a significantly higher percentage of dead bacteria than the saline control (P < 0.05). There was no significant difference between NaOCl + etidronic acid and NaOCl-EDTA-NaOCl (P > 0.05), whereas both groups brought about more bacterial reduction than NaOCl-EDTA (P < 0.05). There was no significant difference between diode laser and Er:YAG laser in any of the groups (P > 0.05). Both diode and Er:YAG laser were more effective than ultrasonic activation and conventional syringe irrigation in reducing E. fecalis biofilms (P < 0.05). The use of NaOCl after or in combination with a chelator caused the greatest reduction of E. faecalis. Diode laser and Er:YAG laser activation were superior to ultrasonics in dentinal tubule disinfection.

Efficacy of different irrigation techniques in the removal of calcium hydroxide from a simulated internal root resorption cavity

To evaluate the efficacy of six irrigation techniques to remove calcium hydroxide (CH) from a simulated internal root resorption cavity. The root canals of 100 single-rooted teeth were prepared using the ProTaper system to size F5. The roots were split longitudinally, and standardized simulated internal root resorption cavities were prepared in the two root halves. The root halves were reassembled, and CH was placed into the root canals, with the exception of five teeth that served as the negative control group. Another five teeth (the positive control group) were not subjected to the CH removal procedure. Ninety teeth were randomly divided into six experimental groups (n=15), according to the final irrigation techniques used: conventional syringe irrigation (CSI), CanalBrush (CB), passive ultrasonic irrigation (PUI), self-adjusting file (SAF) system, EndoActivator (EA), and apical negative pressure irrigation (EndoVac system). Five millilitres of 3% NaOCl and 17% EDTA were used in all experimental groups during the CH removal procedure. The amount of remaining CH was evaluated under a stereomicroscope at 20×magnification, using a 4-grade scoring system. The data were statistically compared using the Kruskal-Wallis and Mann-Whitney U-tests (P<0.05). Remnants of CH in simulated internal root resorption cavities were found in all experimental groups. SAF and PUI were superior to the other groups (P<0.05); however, there was no significant difference between the SAF and PUI (P>0.05). There were also no significant differences between the CSI, CB, EA and EndoVac groups (P>0.05). None of the irrigation techniques was able to completely remove CH from a simulated internal root resorption cavity.

Spectrophotometric Determination of Irrigant Extrusion Using Passive Ultrasonic Irrigation, EndoActivator, or Syringe Irrigation

IntroductionSodium hypochlorite (NaOCl) irrigation is critical to endodontic success, and several new methods have been developed to improve irrigation efficacy (eg, passive ultrasonic irrigation [PUI] and EndoActivator [EA]). Using a novel spectrophotometric method, this study evaluated NaOCl irrigant extrusion during canal irrigation. MethodsOne hundred fourteen single-rooted extracted teeth were decoronated to leave 15 mm of the root length for each tooth. Cleaning and shaping of the teeth were completed using standardized hand and rotary instrumentation to an apical file size #40/0.04 taper. Roots were sealed (not apex), and 54 straight roots (n = 18/group) and 60 curved roots (>20° curvature, n = 20/group) were included. Teeth were irrigated with 5.25% NaOCl by 1 of 3 methods: passive irrigation with needle, PUI, or EA irrigation. Extrusion of NaOCl was evaluated using a pH indicator and a spectrophotometer. Standard curves were prepared with known amounts of irrigant to quantify amounts in unknown samples. ResultsIrrigant extrusion was minimal with all methods, with most teeth showing no NaOCl extrusion in straight or curved roots. Minor NaOCl extrusion (1–3 μL) in straight roots or curved roots occurred in 10%–11% of teeth in all 3 irrigant methods. Two teeth in both the syringe irrigation and the EA group extruded 3–10 μL of NaOCl. ConclusionsThe spectrophotometric method used in this study proved to be very sensitive while providing quantification of the irrigant levels extruded. Using the PUI or EA tip to within 1 mm of the working length appears to be fairly safe, but apical anatomy can vary in teeth to allow extrusion of irrigant.

Traditional and contemporary techniques for optimizing root canal irrigation

Canal irrigation during root canal treatment is an important component of chemo-mechanical debridement of the root canal system. Traditional syringe irrigation can be enhanced by activating the irrigant to provide superior cleaning properties. This activation can be achieved by simple modifications in current technique or by contemporary automated devices. Novel techniques are also being developed, such as the Self-adjusting File (Re-Dent-Nova, Ra'anana, Israel), Ozone (Healozone, Dental Ozone, London, UK), Photoactivated Disinfection and Ultraviolet Light Disinfection. This paper reviews the techniques available to enhance traditional syringe irrigation, contemporary irrigation devices and novel techniques, citing their evidence base, advantages and disadvantages. Recent advances in irrigation techniques and canal disinfection and debridement are relevant to practitioners carrying out root canal treatment.

Iatrogenic Subcutaneous Emphysema of Endodontic Origin – Case report with Literature Review

Surgical emphysema is well known and many case reports have been published on this. Many authors have reported this as a complication post dentoalveolar treatment. Diffusion of air into facial planes and periorbital area during endodontic procedures has been rarely reported. The use of three way air syringe and forceful irrigation of root canal can lead to surgical emphysema of subcutaneous tissue planes in and around the teeth which are involved. This case report highlights one such complication seen during endodontic treatment, discusses aetiology, complications and conservative management of this dental office emergency.

The effect of four different irrigation systems in the removal of a root canal sealer

The aim of this study was to compare the efficiency of sonic, ultrasonic, and hydrodynamic devices in the removal of a root canal sealer from the surface and from simulated irregularities of root canals. Fifty-three root canals with two standardized grooves in the apical and coronal parts of longitudinally split roots were covered with AH Plus root canal sealer. Compared were the effects of (control) syringe irrigation, (1) CanalBrush, (2) passive ultrasonic irrigation, (3) EndoActivator, and (4) RinsEndo on the removal of the sealer. The specimens were divided into four groups (N = 12) and one control group (N = 5) via randomization. The amount of remaining sealer in the root canal irregularities was evaluated under a microscope using a 4-grade scoring system, whereas the remaining sealer on the root canal surface was evaluated with a 7-grade scoring system. Passive ultrasonic irrigation is more effective than the other tested irrigation systems or syringe irrigation in removing sealer from root canal walls (p < 0.01). None of the techniques had a significant effect on cleaning the lateral grooves. Within the limitations of this study protocol ultrasonic irrigation shows a superior effect on sealer removal from the root canal surface during endodontic retreatment. Cleaning of lateral grooves seems not to be possible with one of the techniques investigated. Incomplete removal of root canal sealer during re-treatment may cause treatment failure. Passive Ultrasonic irrigation seems to be the most effective system to remove sealer from a root canal.

Effect of Different Final Irrigation Methods on the Removal of Calcium Hydroxide from an Artificial Standardized Groove in the Apical Third of Root Canals

IntroductionThe aim of this study was to compare the efficacy of conventional syringe, ultrasonic, EndoVac (Discus Dental, Culver City, CA), and Self-Adjusting File (SAF) (Re-Dent-Nova, Ra'nana, Israel) irrigation systems in removing calcium hydroxide (Ca[OH]2) from simulated root canal irregularities. MethodsThe root canals of 88 extracted single-rooted teeth were prepared using ProTaper rotary instruments (Dentsply Maillefer, Ballagiues, Switzerland) up to size F4. The roots were split longitudinally, and a standardized groove was prepared in the apical part of 1 segment. The root halves were reassembled, and Ca(OH)2 medicament was placed into the root canals using a Lentulo spiral. The roots were randomly divided into 4 experimental groups and 2 control groups according to the different irrigation systems used: conventional syringe irrigation, continuous passive ultrasonic irrigation (PUI), EndoVac irrigation, and SAF irrigation. Each group was then divided into 2 subgroups (n = 10) according to the irrigation protocol: subgroup 1: 10 mL 2.5% NaOCl and subgroup 2: 10 mL 17% EDTA + 10 mL 2.5% NaOCl. The amount of remaining medicament was evaluated under a stereomicroscope at 30× magnification using a 4-grade scoring system. The influences of the different Ca(OH)2 medicament removal methods and irrigation protocols were statistically evaluated using 2-way analysis of variance and Tukey post hoc tests. ResultsIn the NaOCl-irrigated groups, PUI removed significantly more Ca(OH)2 medicament than the other techniques (P < .05). There was no significant difference among the other groups (P > .05). In the EDTA/NaOCl-irrigated groups, the SAF and PUI removed significantly more Ca(OH)2 than the other techniques (P < .05). ConclusionsThe use of the SAF system with the combination of EDTA and NaOCl enhanced Ca(OH)2 removal when compared with the use of only NaOCl irrigation with the SAF. Continuous PUI and SAF were more effective than EndoVac, and conventional syringe irrigation in the removal of the Ca(OH)2 medicament from an artificial standardized groove in the apical part of the root canal.

Radiographic Healing after a Root Canal Treatment Performed in Single-rooted Teeth with and without Ultrasonic Activation of the Irrigant: A Randomized Controlled Trial

IntroductionThe aim of this study was to compare the outcome of a root canal treatment with and without additional ultrasonic activation of the irrigant. MethodsSingle-rooted teeth with radiographic evidence of periapical bone loss were randomly assigned to 2 treatment groups. In both groups syringe irrigation was performed, and in one group the irrigant was also activated by ultrasound. Ten to 19 months after treatment, the teeth were examined by using periapical radiography (PA) and cone-beam computed tomography (CBCT). Area and volume of the periapical lesions were measured, and the outcome was presented in 4 categories: absence, reduction or enlargement of the radiolucency, or uncertain. Lesions were classified as reduced or enlarged when the change in size of the radiolucency was 20% or more. ResultsThe recall rate was 82%, and 84 teeth were analyzed. CBCT detected significantly more post-treatment lesions than PA (P = .038), but the percentages of absence and reduction of the radiolucency together revealed by CBCT and PA were similar (P = .383). The CBCT results showed that absence of the radiolucency was observed in 16 of 84 teeth (19%) and reduction of the radiolucency in 61 of 84 teeth (72.6%), but there was no significant difference between the results of the 2 groups (P = .470). Absence and reduction of the radiolucency together were observed in the ultrasonic group in 39 of 41 teeth (95.1%) and in the syringe group in 38 of 43 teeth (88.4%). ConclusionsRoot canal treatments with and without additional ultrasonic activation of the irrigant contributed equally to periapical healing.

Assessment of smear layer removal protocols in curved root canals

This study sought to assess if the final rinse protocol interferes with the smear layer removal in the apical area of curved canals. Sixty-four extracted human mandibular molars with curved mesial roots were instrumented with rotary files and divided into six experimental groups for final rinse: 1EDTA (syringe irrigation with 1 mL of 17% ethylenediaminetetraacetic acid (EDTA) ), 5EDTA (syringe irrigation with 5 mL of 17% EDTA), 1EDTA-P (syringe irrigation with 1 mL of 17% EDTA + pumping with gutta-percha point), 5EDTA-P (syringe irrigation with 5 mL of 17% EDTA + pumping with gutta-percha point), 1EDTA-EA (syringe irrigation with 1 mL of 17% EDTA + EndoActivator) and 5EDTA-EA (syringe irrigation with 5 mL of 17% EDTA + EndoActivator). Final rinsing was carried out over 3 min. The specimens were split lengthwise and observed under a scanning electron microscope using a score criterion. Comparison among the groups showed statistically significant difference only between the 5EDTA-EA group and the other groups (Kruskal-Wallis and Dunn's post-hoc tests, P < 0.05). The combination of 5 mL of 17% EDTA and 3 mL of 2.5% sodium hypochlorite (NaOCl) with the EndoActivator removed smear layer from the apical area of curved root canals more effectively than the other protocols used.

Comparison of the Antibacterial Effect and Smear Layer Removal Using Photon-Initiated Photoacoustic Streaming Aided Irrigation Versus a Conventional Irrigation in Single-Rooted Canals: AnIn VitroStudy

The Er:YAG laser with photon-induced photoacoustic streaming (PIPS) technique was reported to be effective in root canal disinfection. This study attempted to further investigate the antibacterial efficacy and smear layer removal ability of PIPS in comparison with conventional syringe irrigation in vitro. For antibacterial analysis, 48 single-rooted human teeth were prepared and inoculated with Enterococcus faecalis, and then divided into six groups of eight roots each. The colony-forming units (CFUs) per milliliter were determined after infection as the baseline. Then, the teeth were subjected to either PIPS plus 3% sodium hypochlorite (PIPS+NaOCl) or conventional syringe irrigation with 0.9% saline, 3% NaOCl, 17% ethylenediaminetetraacetic acid (EDTA), 0.2% chlorhexidine gluconate (CHX), or 3% NaOCl alternating with 17% EDTA. The reduction of CFUs in the individual group was determined. Additionally, scanning electron microscopy (SEM) examination of the canal walls for E. faecalis colonization was performed. For comparing the smear removal efficacy, another 48 single-rooted teeth, assigned to different groups as mentioned, were irrigated after mechanical instrumentation. The presence of a smear layer at different levels of the root canal was scored by SEM examination. No significant differences were found in CFU reduction. No bacteria could be observed by SEM in the NaOCl, NaOCl+EDTA, and PIPS+NaOCl groups. The scores of smear layer of the NaOCl+EDTA and PIPS+NaOCl groups were significantly lower than those of the other groups in the coronal and middle third of the root canal. None of the methods can effectively remove smear layer in the apical third. PIPS system supplied with NaOCl and conventional syringe irrigation with NaOCl+EDTA are comparable in their ability to remove E. faecalis and smear layer in single-rooted canals.

Surface change of root canal dentin after the use of irrigation activation protocols: Electron microscopy and an energy‐dispersive X‐ray microanalysis

This study evaluated the mineral contents of root-canal dentin after treatment with different irrigation activation protocols. One hundred and eight maxillary lateral incisor teeth were randomly divided into eight experimental groups and one control group. Root canals were prepared using ProTaper rotary files, with the exception of the Self-Adjusting File (SAF) group. Canals were irrigated with 2 mL of 5% sodium hypochlorite (NaOCl) at each instrument change, and received a final flush with 10 mL of 17% ethylenediaminetetraacetic acid (EDTA) and 10 mL of 5% NaOCl for 1 min. The control group was irrigated with distilled water. Group I (GI): Needle syringe irrigation; Group II (GII): NaviTip FX; Group III (GIII): CanalBrush; Group IV (GIV): Manual dynamic activation with gutta-percha; Group V (GV): Passive ultrasonic irrigation; Group VI (GVI): EndoActivator; Group VII (GVII): EndoVac; Group VIII (GVIII): SAF. The level of elemental composition was analyzed by a scanning electron microscopy and an energy-dispersive spectrometer (EDS) system. The results were then statistically analyzed by one-way ANOVA and Tukey tests. Ca/P ratio was changed after treatment with SAF and EndoActivator. The Ca, P, Mg, and S level changes were not statistically significant (P > 0.05). Final irrigation activation protocols did not alter the mineral level of root dentin surface.

Formation and removal of apical vapor lock during syringe irrigation: a combined experimental and Computational Fluid Dynamics approach

(i) To evaluate the effect of needle type and insertion depth, root canal size and irrigant flow rate on the entrapment of air bubbles in the apical part of a root canal (apical vapor lock) during syringe irrigation using experiments and a Computational Fluid Dynamics (CFD) model, (ii) to investigate whether the irrigant contact angle affects bubble entrapment, (iii) to examine if an established vapor lock can be removed by syringe irrigation. Bubble entrapment during irrigation of straight artificial root canals of size 35 or 50 was evaluated by real-time visualizations. The irrigant was delivered by a closed-ended or an open-ended needle positioned at 1 or 3 mm short of working length (WL) and at a flow rate of 0.033-0.260 mL s(-1) . Results were analysed by nonparametric tests at 0.05 significance. Selected cases were also simulated by a two-phase CFD model. A vapor lock was observed in 48% of the cases investigated experimentally. Increasing the apical size, using an open-ended needle, positioning the needle closer to WL and delivering the irrigant at higher flow rate resulted in significantly smaller vapor lock. An increased contact angle resulted in the entrapment of a larger bubble when a low flow rate was used. Both brief insertion of the needle to WL whilst irrigating at a flow rate of 0.083 mL s(-1) and delivering the irrigant at 0.260 mL s(-1) without changing the needle position were capable of removing an established vapor lock. Apical vapor lock may occur under certain conditions, but appears to be easily prevented or removed by syringe irrigation.

Irrigation dynamics associated with positive pressure, apical negative pressure and passive ultrasonic irrigations: a computational fluid dynamics analysis.

Complexities in root canal anatomy and surface adherent biofilm structures remain as challenges in endodontic disinfection. The ability of an irrigant to penetrate into the apical region of a canal, along with its interaction with the root canal walls, will aid in endodontic disinfection. The aim of this study was to qualitatively examine the irrigation dynamics of syringe irrigation with different needle tip designs (open-ended and closed-ended), apical negative pressure irrigation with the EndoVac® system, and passive ultrasonic-assisted irrigation, using a computational fluid dynamics model. Syringe-based irrigation with a side-vented needle showed a higher wall shear stress than the open-ended but was localised to a small region of the canal wall. The apical negative pressure mode of irrigation generated the lowest wall shear stress, while the passive-ultrasonic irrigation group showed the highest wall shear stress along with the greatest magnitude of velocity.

Tibial cleaning method for cemented total knee arthroplasty: An experimental study.

Background:The survival rate of cemented knee prosthesis depends among other factors on optimal cement-bone contact, nevertheless no standard exists for cementing technique of tibial components. The aim of this study was to determine which tibial surface preparation technique leads to the best bone-cement contact.Materials and Methods:Human tibial plateau specimens were cleaned in four different ways before cementing: a) no cleaning, b) manual syringe irrigation, c) fracture brush cleaning, and d) pulsatile jet-lavage. The specimens were cut into transverse sections and the bone cement contact distance was calculated for every 10 mm and the cement penetration depth was measured. Both values were statistically analyzed (ANOVA).Results:The longest bone-cement contact (62 mm) was seen after PJL, the shortest (10.6 mm) after no cleaning at all. The deepest cement penetration (4.1 mm) again was seen after PJL, the least (0.7 mm) after no cleaning. Statistically, PJL yielded the longest bone-cement contact and deepest cement penetration.Conclusion:The results supports the use of pulsatile jet-lavage before cementing tibial components in knee arthroplasty.

The effect of the irrigant QMix on removal of canal wall smear layer: an ex vivo study

The aim of this study is to evaluate the effectiveness over application time of different formulations of a novel endodontic irrigant (QMix™ 2in1) composed of a polyaminocarboxylic acid chelating agent, a bisbiguanide antimicrobial agent, a surfactant and deionized water to remove the root canal smear layer and expose patent dentinal tubules compared to a standard solution of 17% EDTA. Eighty human tooth roots from extracted, single-rooted teeth were instrumented (size 40.06) using 0.2 mL of sodium hypochlorite (6.15%) between each file size with a 3 mL water rinse after final instrumentation. Eight groups of 10 roots were irrigated with 3 mL of different formulations of QMix: QMix A, QMix B, and QMix C, or 17% EDTA for 60 and 90 s, respectively, then rinsed with 5 mL of sterile water. The roots were irrigated using a standard irrigation syringe and a 30 ga side-vent needle with an apical-coronal motion to within 1 mm of the working length. The coronal, middle and apical thirds of one canal surface of each root was evaluated at 1000× using scanning electron microscopy. The presence of smear layer was scored using a 5-point scale. Data were analyzed with the Kruskal-Wallis rank sums test, the Steel-Dwass, all-pairs comparison test, and the Steel method (with control) test. Irrigant type was highly significant (p < 0.007). Combined 60 and 90 s exposure data indicated QMix A (p = 0.014) and QMix C (p = 0.028) were superior to EDTA. While at the 90 s exposure time, smear layer removal by solutions QMix A (p = 0.043), QMix B (p = 0.018), and QMix C (p = 0.011) was superior to EDTA. All irrigants removed smear layer more effectively at the coronal and middle levels compared to the apical level (p < 0.001). Analysis showed all three QMix formulations were superior to EDTA in smear layer removal and exposure of dentinal tubules in the root canal system in single-rooted teeth.

Multivariate analysis of the cleaning efficacy of different final irrigation techniques in the canal and isthmus of mandibular posterior teeth

ObjectivesThe aim of this study was to compare the cleaning efficacy of different final irrigation regimens in canal and isthmus of mandibular molars, and to evaluate the influence of related variables on cleaning efficacy of the irrigation systems.Materials and MethodsMesial root canals from 60 mandibular molars were prepared and divided into 4 experimental groups according to the final irrigation technique: Group C, syringe irrigation; Group U, ultrasonics activation; Group SC, VPro StreamClean irrigation; Group EV, EndoVac irrigation. Cross-sections at 1, 3 and 5 mm levels from the apex were examined to calculate remaining debris area in the canal and isthmus spaces. Statistical analysis was completed by using Kruskal-Wallis test and Mann-Whitney U test for comparison among groups, and multivariate linear analysis to identify the significant variables (regular replenishment of irrigant, vapor lock management, and ultrasonic activation of irrigant) affecting the cleaning efficacy of the experimental groups.ResultsGroup SC and EV showed significantly higher canal cleanliness values than group C and U at 1 mm level (p < 0.05), and higher isthmus cleanliness values than group U at 3 mm and all levels of group C (p < 0.05). Multivariate linear regression analysis demonstrated that all variables had independent positive correlation at 1 mm level of canal and at all levels of isthmus with statistical significances.ConclusionsBoth VPro StreamClean and EndoVac system showed favorable result as final irrigation regimens for cleaning debris in the complicated root canal system having curved canal and/or isthmus. The debridement of the isthmi significantly depends on the variables rather than the canals.

Irrigation protocol among endodontic faculty and post-graduate students in dental colleges of India: A survey

Background:Irrigation protocol is the most critical step during the disinfection of an infected root canal system.Aim:The purpose of this study was to determine the root canal irrigation trends being practiced among the endodontic teaching faculty and post-graduate students in the dental colleges present in India.Materials and Methods:A postal invitation to participate in this national survey was sent to the Department of Conservative Dentistry and Endodontic of 294 Dental Colleges present in India. A total of 2389 forms were successfully delivered out of which 794 duly filled forms were received back. Survey participants were asked about their irrigant selection, irrigant concentration, smear layer removal protocol, and use of adjuncts during irrigation.Results:This survey elicited a positive response rate of 33.23%. Our data indicated that 92.8% of respondents use sodium hypochlorite (NaOCl) as the primary endodontic irrigant, with 26 gauge needle being most preferred for syringe irrigation, with 49.3% of them using it at a concentration of 2.6-4.0%. 68% of our respondents aim to remove the smear layer during the endodontic treatment while 47% reported using ultrasonic activation as an adjunct during their irrigation protocol.Conclusions:The findings of this survey are that the majority of teaching institutions in India are employing NaOCl (2.6-4.0%) as the primary endodontic irrigant. The concept of smear layer removal is high (68%), and there is a general trend (78%) to modify the irrigation protocol according to the status of the pulp, status of the periapex and in retreatment cases.

Comparison of calcium hydroxide removal by self-adjusting file, EndoVac, and CanalBrush agitation techniques: An in vitro study

Objectives:This study comparatively evaluated the efficacy of self-adjusting file (SAF), Endovac, and CanalBrush irrigant agitation protocols in removing calcium hydroxide (Ca(OH)2) from the root canals.Materials and Methods:Sixty extracted human mandibular canine teeth were instrumented with ProTaper rotary instruments to size #40 and dressed with Ca(OH)2. The roots were randomly assigned to four groups according to irrigant agitation protocol used (n = 15). In Group 1: Conventional syringe irrigation (no activation, control); Group 2: Rotary brush agitation (CanalBrush); Group 3: Apical negative pressure irrigation (EndoVac system); and Group 4: Sonic agitation (SAF) were used. Scanning electron microscopic (SEM) evaluation was done for assessment of Ca(OH)2 removal in the coronal and apical thirds. Statistical analysis was performed by Wilcoxon and Kruskal-Wallis tests.Results:There were statistically significant differences among the groups (P = 0.218). A statistically significant difference was seen between the test groups in Ca(OH)2 removal from the apical third of the canal (P < 0.05). In the coronal third, there was no difference between the groups (P > 0.05). The most efficient Ca(OH)2 removal in apical third was recorded in Group 3 (EndoVac) and Group 4 (SAF) (P < 0.05). In Group 4 (sonic agitation), there was no significantly difference between Ca(OH)2 removal in coronal and apical thirds.Conclusions:SAF and EndoVac showed significantly better performance than CanalBrush and conventional syringe irrigation in removing Ca(OH)2 from apical third of the root canals.

Oscillation characteristics of endodontic files: numerical model and its validation

During a root canal treatment, an antimicrobial fluid is injected into the root canal to eradicate all bacteria from the root canal system. Agitation of the fluid using an ultrasonically vibrating miniature file results in a significant improvement in the cleaning efficacy over conventional syringe irrigation. Numerical analysis of the oscillation characteristics of the file, modeled as a tapered, driven rod, shows a sinusoidal wave pattern with an increase in amplitude and decrease in wavelength toward the free end of the file. Measurements of the file oscillation with a scanning laser vibrometer show good agreement with the numerical simulation. The numerical model of endodontic file oscillation has the potential for predicting the oscillation pattern and fracture likeliness of various file types and the acoustic streaming they induce during passive ultrasonic irrigation.