Effectiveness of various irrigation activation protocols and the self-adjusting file system on smear layer and debris removal. Smear layer removal with passive ultrasonic irrigation and the NaviTip FX: a scanning electron microscopic study. Efficacy of four different irrigation techniques combined with 60°C 3% sodium hypochlorite and 17% EDTA in smear layer removal A Scanning electron microscopic evaluation of intracanal smear layer removal by two different final irrigation activation systems Effect of different irrigant activation protocols on push-out bond strength Effect of passive ultrasonic irrigation and manual dynamic irrigation on smear layer removal from root canals in a closed apex in vitro model. Comparison of the effectiveness of three irrigation techniques in reducing intracanal Enterococcus faecalis populations: an in vitro study. Effects of subgingival chlorhexidine irrigation on peri-implant maintenance. Comparison of irrigant penetration up to working length and into simulated lateral canals using various irrigating techniques. Comparative evaluation of postoperative pain after using endodontic needle and EndoActivator during root canal irrigation: A randomised controlled trial. Root canal debridement efficacy of different final irrigation protocols. Hard tissue debris removal from the mesial root canal system of mandibular molars with ultrasonically and laser-activated irrigation: a micro-computed tomography study Smear Layer Evaluation on Root Canal Preparation with Manual and Rotary Techniques using EDTA as an Irrigant: A Scanning Electron Microscopy Study. In vivo efficacy of three different endodontic irrigation systems for irrigant delivery to working length of mesial canals of mandibular molars. Efficacy of a new brush-covered irrigation needle in removing root canal debris: a scanning electron microscopic study. The efficacy of dynamic irrigation using a commercially available system (RinsEndo) determined by removal of a collagen 'bio-molecular film' from an ex vivo model. A comparative study of the debridement efficacy and apical extrusion of dynamic and passive root canal irrigation systems
The purpose of the present study is to evaluate smear layer generation and residual debris after using self-adjusting file ( SAF ) or rotary instrumentation and to compare the debris and smear layer removal efficacy of the SAF cleaning/shaping irrigation system against final agitation techniques . One hundred and eight maxillary lateral incisor teeth were r and omly divided into nine experimental groups ( n = 12 ) , and root canals were prepared using ProTaper Universal rotary files , with the exception of the SAF instrumentation group . During instrumentation , root canals were irrigated with a total of 16 mL of 5 % NaOCl . For final irrigation , rotary-instrumented groups were irrigated with 10 mL of 17 % EDTA and 10 mL of 5 % NaOCl using different irrigation agitation regimens ( syringe irrigation with needles , NaviTip FX , manual dynamic irrigation , CanalBrush , EndoActivator , EndoVac , passive ultrasonic irrigation ( PUI ) , and SAF irrigation ) . In the SAF instrumentation group , root canals were instrumented for 4 min at a rate of 4 mL/min with 5 % NaOCl and received a final flush with same as syringe irrigation with needles . The surface of the root dentin was observed using a scanning electron microscope . The SAF instrumentation group generated less smear layer and yielded cleaner canals compared to rotary instrumentation . The EndoActivator , EndoVac , PUI , and SAF irrigation groups increased the efficacy of irrigating solutions on the smear layer and debris removal . The SAF instrumentation yielded cleaner canal walls when compared to rotary instrumentation . None of the techniques completely removed the smear layer from the root canal walls OBJECTIVE The aim of this study was to compare the effect of continuous , intermittent passive ultrasonic irrigation ( PUI ) and active scrubbing of irrigants with NaviTip FX ( Ultradent , South Jordan , UT ) in removing smear layer . STUDY DESIGN Forty single-rooted teeth were r and omly divided into 5 test groups and subjected to final irrigation with 17 % EDTA followed by 2.5 % NaOCl for 1 minute each using different activation methods : no activation ( control ) , brushing with NaviTip FX , continuous PUI with irrigant delivered at pulp chamber , continuous PUI with irrigant delivered through the ultrasonic unit , and intermittent PUI . Specimens were examined under scanning electron microscope , and the data were analyzed using Friedman 2-way analysis of variance , Kruskal-Wallis , and Mann-Whitney U tests . RESULTS NaviTip FX and intermittent PUI showed significantly lower smear score than other groups at the 3 mm level ( P < .05 ) . CONCLUSIONS Both brush and intermittent ultrasonic activation were effective in the removal of smear layer from the apical third Background Efforts to improve the efficacy of smear layer removal by applying irrigant activation at the final irrigation or by elevating the temperature of the irrigant have been reported . However , the combination of such activation protocol s with 60 ° C 3 % sodium hypochlorite ( NaOCl ) has seldom been mentioned . The aim of this study was to compare the efficacy in smear layer removal of four different irrigation techniques combined with 60 ° C 3 % NaOCl and 17 % EDTA . Methods Fifty single-rooted teeth were r and omly divided into five groups ( n = 10 ) according to the irrigant agitation protocol s used during chemomechanical preparation(Dentsply Maillefer , Ballaigues , Switzerl and ): a side-vented needle group , a ultrasonic irrigation ( UI ) group , a NaviTip FX group , an EndoActivator group , and a control group ( no agitation ) . After each instrumentation , the root canals were irrigated with 1 mL of 3 % NaOCl at 60 ° C for 1 minute , and after the whole instrumentation , the root canals were rinsed with 1 mL of 17 % EDTA for 1 minute . Both NaOCl and EDTA were activated with one of the five irrigation protocol s. The efficacy of smear layer removal was scored at the apical , middle and coronal thirds . The Data were statistically analyzed using SAS version 9.2 for Windows ( rank sum test for a r and omised block design and ANOVA ) . Results No significant differences among the NaviTip FX group , EndoActivator group and control groups , and each of these groups showed a lower score than that of UI group ( P < 0.05 ) . Within each group , all three thirds were ranked in the following order : coronal > middle > apical ( P < 0.05 ) . In the coronal third , the NaviTip FX group was better than UI group . In the middle and apical third , the differences were not significant among any of the groups . Conclusions Even without any activation , the combination of 60 ° C 3 % NaOCl and 17 % EDTA  could remove the smear layer effectively , similar to NaviTip FX or EndoActivator , and these three protocol s were more effective than UI . However , regardless of different types of irrigation technique applied , complete removal of the smear layer was not achieved , particularly in the apical third Aim : The aim of this study was to compare smear layer removal at apical 1 mm level after final irrigation activation with an EndoVac system and Max-I probe . Material s and Methods : Fifty freshly extracted maxillary central incisors were r and omly divided into two groups after completing cleaning and shaping with ProTaper rotary files . In one group , final irrigation was performed with an EndoVac system while in the other group final irrigation was performed with a 30 gauge Max-I probe . 3 % sodium hypochlorite and 17 % ethylenediaminetetracetic acid were used as final irrigants in all teeth . After instrumentation and irrigation , the teeth were sectioned longitudinally into buccal and palatal halves and viewed under a scanning electron microscope for evaluation of the smear layer . Statistical analysis was performed using the Kruskal Wallis and Mann-Whitney U tests . Results : The EndoVac group showed significantly better smear layer removal compared with the Max-I probe at the apical 1 mm level . Conclusion : An apical negative pressure system ( EndoVac ) results in better debridement at apical 1 mm when compared with side-vented closed ended needle irrigation ( Max-I probe ) The study aim ed to evaluate the effect of various final irrigant activation protocol s on push-out bond strength of fiber post . Thirty-two single-rooted human maxillar central teeth were sectioned below the cementoenamel junction , instrumented and obturated . Post-space preparation was performed , and roots were r and omly divided into eight groups ( n = 4 ) according to the final irrigant activation protocol s ; distilled water was used as an irrigant in group 1 . The other groups were treated with 2.5 % NaOCl and 17 % EDTA . Conventional syringe irrigation ( CSI , no activation ) was used in group 2 . Irrigation solutions were activated using passive ultrasonic irrigation ( PUI , group 3 ) , EndoVac apical negative pressure ( ANP , group 4 ) , diode laser ( group 5 ) , neodymium : yttrium – aluminum-garnet ( Nd : YAG ) laser ( group 6 ) , erbium : yttrium – aluminum-garnet ( Er : YAG ) laser ( group 7 ) , and Er : YAG laser using with photon-induced photoacoustic streaming ( PIPS ™ ) technique ( group 8) . In all groups , fiber posts ( White Post DC , FGM ) were luted using Panavia F 2.0 ( Kuraray , Osaka , Japan ) . The specimens were transversally sectioned , and all slices from coronal and apical regions were subjected to push-out tests . The data were calculated as megapascals and analyzed by using two-way analysis of variance followed by post hoc Tukey honestly significant difference ( HSD ) tests . Removing the smear layer increased the bond strength to dentine when compared with the control group ( p < 0.05 ) . The highest bond strength was obtained in the PIPS laser-activated irrigation group ( p < 0.05 ) . Coronal root region presented significantly higher bond strength than the apical region ( p < 0.05 ) . PIPS laser-activated irrigation showed higher efficiency as a final irrigant activation protocol on push-out bond strength of fiber post AIM To compare the effect of passive ultrasonic irrigation with manual dynamic irrigation on smear layer removal from root canals using a closed apex in vitro model . METHODS The root canals of 45 freshly-extracted human single-rooted m and ibular premolar teeth were prepared by the Pro-Taper rotary system to an apical preparation of F4 size . Prepared teeth were r and omly divided into three groups ; two experimental groups and one control group ( n = 15 ) on the basis of the type of activation of final irrigation as follows : ( a ) Group A , 3 % sodium hypochlorite ( NaOCl ) and 17 % ethylenediaminetetraacetic acid ( EDTA ) , no activation received ; ( b ) Group B , 3 % NaOCl and 17 % EDTA , ultrasonic activation with a small file ; and ( c ) Group C , 3 % NaOCl and 17 % EDTA , manual activation with a master gutta-percha point . The prepared teeth were decoronated and split into two halves longitudinally , and observed under a scanning electron microscope to assess the removal of the smear layer . RESULTS In the apical-third region , the mean smear scores for groups B and C were significantly less than those of Group A ( control group ) ( P < 0.05 ) . CONCLUSION Both activation techniques are important adjuncts in removing the smear layer , with manual dynamic activation being a simpler , safer , and more cost-effective technique INTRODUCTION Several irrigation techniques have been recently introduced with the main objective of improving root canal disinfection . This in vitro study aim ed at comparing the intracanal bacterial reduction promoted by chemomechanical preparation with 3 different irrigation techniques . METHODS Root canals from extracted teeth were contaminated with Enterococcus faecalis ATCC 29212 for 7 days and then r and omly distributed into 3 experimental groups of 20 teeth each : group 1 , conventional irrigation with NaviTip needles inserted up to 3 mm short of the working length ; group 2 , same as group 1 , but supplemented with final irrigant activation by the EndoActivator system ; and group 3 , irrigation with the EndoVac system . NaOCl and ethylenediaminetetraacetic acid ( EDTA ) were the irrigants used in all experimental groups . The overall preparation time was kept constant for the groups , but the total volume ranged from 20 mL ( groups 1 and 2 ) to 43 mL ( group 3 ) . The control group was irrigated with saline solution ( total volume , 43 mL ) . Sample s taken before and after chemomechanical procedures were cultured , and the colony-forming units ( CFUs ) were counted . RESULTS Reduction in the bacterial population s was highly significant for all groups . The 3 experimental groups with NaOCl and EDTA as irrigants were significantly more effective than the control group with saline in reducing CFU counts . There were no significant differences between the 3 techniques tested . CONCLUSIONS There was no evident antibacterial superiority of any of the irrigation techniques evaluated in the present in vitro model PURPOSE To evaluate the effect of irrigation with 0.06 % chlorhexidine ( PerioGard ) ( CHX ) using a powered oral irrigator ( Water Pik ) with a special subgingival irrigating tip ( Pik Pocket Subgingival Tip ) compared to rinsing with 0.12 % chlorhexidine gluconate once daily . MATERIAL S AND METHODS Following a prophylaxis , patients were r and omly assigned to an irrigation or a rinse group . The following clinical parameters were measured at baseline and at the 3-month end of the study : Modified Gingival Index ( MGI ) , Plaque Index ( PI ) , Bleeding Index ( BI ) , and Calculus Index ( CI ) . Also , a Stain Index ( SI ) was measured at 3 months . RESULTS Patients irrigating with diluted CHX showed a statistically significant reduction ( P < 0.05 ) from their baseline in the MGI , PI , BI , and CI scores at 3 months . In the rinse group both MGI and BI showed statistically significant reduction from their baseline ( P < 0.05 ) at 3 months . The rinse group showed a nonsignificant ( P > 0.05 ) increase from baseline in CI and a nonsignificant decrease in PI . Intergroup comparisons showed that CHX irrigation produced statistically significantly greater reductions than CHX rinsing in the PI , MGI , and SI . The irrigation group also showed a greater reduction in BI and CI than the rinsing group but these differences were not statistically significant ( P = 0.12 ) . The results of this study suggest that use of diluted 0.06 % CHX when used in a powered irrigator may be a valuable adjunct to oral health in patients with implants AIM To evaluate the effect of an apical negative pressure system , a passive ultrasonic irrigation system and a combination of both apical negative pressure and passive ultrasonic irrigation on the penetration of the  irrigating contrast solution ( ICS ) up to working length and into simulated lateral canals . METHODOLOGY The root canals of 64 single-rooted teeth were instrumented using the ProTaper rotary system . In each sample , three simulated lateral canals were created at 2 , 4 and 6 mm levels from the root apex using a 06-size C+ file ( Dentsply Maillefer , Ballaigues , Switzerl and ) . Sample s were r and omly assigned into 4 experimental groups ( n = 16 ) : group I - conventional needle irrigation , group II - passive ultrasonic irrigation , group III - apical negative irrigation system and group IV - combination of passive ultrasonic irrigation and apical negative pressure irrigation system . To examine irrigating solution penetration , Indian ink was mixed with 5.25 % NaOCl and delivered into the root canals . Sample s were then assessed by direct observation of the images taken using Canon EOS rebel T3 . The depth of penetration of ICS up to the working length and into the simulated lateral canals was analysed using chi-squared tests . RESULTS The combination ( ANP and PUI ) and ANP group had significantly deeper ICS penetration up to the working length ( P < 0.001 ) . The combination ( ANP and PUI ) and the PUI group exhibited significantly greater ICS penetration into lateral canals at the 6 mm level ( P < 0.001 ) . At the 4 and 2 mm levels , the combination of ANP and PUI had significantly greater ICS penetration into the lateral canals than the other groups ( P < 0.001 ) . CONCLUSIONS The combination of ANP and PUI was the only group able to achieve irrigating contrast solution penetration both up to the working length and into lateral canals The purpose of this study was to evaluate and compare the postoperative level of pain after activation of irrigants using EndoActivator with conventional needle irrigation during root canal therapy . In this prospect i ve r and omised clinical trial , 72 symptomatic irreversible pulpitis patients were selected . Based on block r and omisation after routine root canal preparation , patients were assigned to two groups . In group EN , procedures were performed with endodontic irrigating needle ( n = 36 ) while group EA received activation using EndoActivator ( n = 36 ) in the final irrigation protocol . All the participants were called through phone at 8 , 24 and 48 h to analyse pain score using visual analogue scale . Those patients who developed pain were prescribed ibuprofen 200 mg . Pain score and frequency of tablet intake were recorded and statistically analysed . Results showed that group EA result ed in significantly less postoperative pain and analgesics intake than group EN . In conclusion , within the limitations of this study , the activation of irrigants using EndoActivator can be considered an effective method for reducing postoperative pain AIM To compare the smear layer and debris removal effectiveness of four root canal irrigation protocol s as well as their effectiveness in removing remaining soft tissues in curved root canals . METHODOLOGY The mesiobuccal and mesial root canals of 107 extracted human maxillary and m and ibular molars were instrumented using Mtwo rotary NiTi instruments then r and omly divided into four groups according to a final rinse protocol : Group 1 ( n = 28 ) - manual agitation of 1 % NaOCl and 15 % EDTA ; Group 2 ( n = 26 ) - CanalBrush agitation of 1 % NaOCl and 15 % EDTA ; Group 3 ( n = 26 ) - 3 % H(2 ) O(2 ) alternated with 1 % NaOCl ; Group 4 ( n = 27 ) - passive ultrasonic agitation of 1 % NaOCl and 15 % EDTA . All irrigation protocol s were performed in a closed system . Eleven roots per group were prepared and histologically stained ( H&E ) to assess percentage of remaining pulpal tissues in the apical thirds . The remaining specimens were split longitudinally and examined under scanning electron microscope at ×2000 magnification to assess smear layer and debris removal . Image Pro Plus 6.0 software was used to analyse smear layer and remaining pulp tissue . Debris presence was scored by two blinded investigators using a five-point scale . Data were analysed using Univariate analysis of variance ( GenStat 13 , α = 0.05 ) . RESULTS CanalBrush and passive ultrasonic irrigation were equally effective with significantly less smear layer and debris than manual agitation and H(2 ) O(2 ) alternated with NaOCl ( P < 0.05 ) . The H(2 ) O(2 ) alternated with NaOCl protocol was significantly more effective in removing pulp tissue remnants in the apical level than manual agitation ( P = 0.009 ) and passive ultrasonic irrigation ( P = 0.01 ) . CONCLUSIONS CanalBrush was as effective as passive ultrasonic irrigation in smear layer and debris removal . Alternating H(2 ) O(2 ) with NaOCl was effective in removing soft tissues from root canal complexities . Further studies are required to evaluate effectiveness of this regimen taking into account irrigant volume differences and effect of root canal system configuration This study is to investigate the efficacy of different irrigant activation techniques on removal of accumulated hard tissue debris ( AHTD ) in mesial roots of human m and ibular molars . Extracted human m and ibular molars with an isthmus between the mesial root canals were selected based on micro-CT ( μCT ) scans . The mesial canals were instrumented to an apical diameter ISO30 using ProTaper rotary files . Teeth were r and omly assigned to three irrigant activation groups ( n = 10 ) : ultrasonically activated irrigation ( UAI ) using a size 20 Irrisafe for 3 × 20 s , laser-activated irrigation ( LAI ) with an Er : YAG laser ( 2940 nm ) and plain 300 μm fiber tip inside the canal ( 20 mJ , 20 Hz , 3 × 20 s ) , and laser-activated irrigation with identical parameters with a 400 μm photon-induced photoacoustic streaming ( PIPS ) tip held at the canal entrance . All teeth were scanned with μCT before and after instrumentation and after irrigant activation . After reconstruction and image processing , the canal system volume filled with hard tissue debris before and after irrigant activation was calculated . Changes in hard tissue debris volumes were compared between groups using one-way ANOVA . The percentage volume of hard tissue debris ( vol% ) was significantly lower after irrigant activation in all groups . Although the lowest debris values were observed in the laser groups , no significant differences in the vol% of accumulated hard tissue debris after activation were observed between groups . Accumulated hard tissue debris was reduced significantly in all activation groups . Ultrasonically and laser-activated irrigation regimens performed similarly in this respect . None of the tested methods was able to render the root canal systems free of debris INTRODUCTION The aim of any root canal treatment is to achieve a canal free of micro organisms , residual pulp remnants , debris and smear layer for the long term success of the procedure . Manual and automated instrumentation techniques along with proper irrigation regime is used to arrive at the aforementioned goal . Many authors focused on the preparation capabilities of various manual and rotary instruments but very few investigators stressed on the actual cleaning abilities of these instruments . AIMS AND OBJECTIVES This study was undertaken to evaluate the cleaning efficiency of manual K flex files and rotary Pro File systems in the root canals using a scanning electron microscope . MATERIAL AND METHODS Thirty single rooted m and ibular first premolars were divided into two groups and r and omized ( the manual group-M and the ProFile group-P ) with respect to the preparation technique . The Manual group was h and instrumented with stainless steel K- Flexofiles by means of a conventional filing technique . The Pro File group was instrumented according to the manufacturer 's instructions using a rotary h and piece . All canals were shaped and cleaned under frequent irrigation with EDTA . Final irrigation was carried out with 3 mL of normal saline solution to neutralize the action of the irrigant . The roots were split , one half of each tooth was selected for further SEM technique analysis and examined under the scanning electron microscope . The canal walls were quantitatively evaluated for the amount of debris and smear layer . The apical , middle and coronal regions of the canal surface , were grade d ( 1 - 5 ) for debris and smear layer . A statistical analysis was performed using a Mann-Whitney Rank Sum test . ProFile performed least effective cleaning . Manual K-Flexofiles led to a grooved pattern . RESULTS AND CONCLUSION A statistically significant difference was observed ( p<0.05 ) between the two instrumentation techniques concerning the amount of debris and smear layer at the apical level . The manually filed canals had less debris and smear layer than those using a rotary technique . It was concluded from this study that none of the instrumentation techniques employed , produced the canal walls which were free of surface debris and smear layer . The manual instrumentation technique was better in cleaning the canals compared to the ProFile rotary Ni-Ti instruments despite the step-back technique used for manual instrumentation . How to cite this article : Manjunatha M , Kini A , Sudhakar V , Sunil K V C , Hiremath V K , Shah A. Smear Layer Evaluation on Root Canal Preparation with Manual and Rotary Techniques using EDTA as an Irrigant : A Scanning Electron Microscopy Study . J Int Oral Health 2013 ; 5(1):66 - 78 INTRODUCTION Many in vitro studies have debated over the ability of different irrigant delivery and /or agitation systems to reach the apical third of curved root canals ; however , little is known about irrigant penetration in vivo . Therefore , the purpose of this study was to compare the efficacy of the conventional endodontic irrigation needle , passive ultrasonic irrigation ( PUI ) , and a negative pressure system for irrigant delivery to working length ( WL ) of mesial canals of m and ibular molars . METHODS Thirty mesial canals of 30 vital m and ibular first or second molars were r and omly assigned into 3 groups ( n = 10 ) : ( 1 ) Monoject syringe with 27-gauge needle ; ( 2 ) PUI with IrriSafe tip ; and ( 3 ) EndoVac system . All canals were treated following the same preparation protocol to size 35/0.04 by using 5.25 % NaOCl as irrigant during preparation procedure . Before obturation , canals were irrigated with 1 mL of a radiopaque solution by using the assigned irrigation system , and a digital radiograph was taken by using a parallel technique . With the aid of image editing software the distance between WL and maximum irrigant penetration was measured . RESULTS Mean distances for Monoject , PUI , and EndoVac groups were 1.51 mm , 0.21 mm , and 0.42 mm , respectively . Analysis of variance test showed statistically significant differences between groups ( P < .001 ) . Tukey honestly significant difference test showed statistically significant differences between the Monoject group and the other 2 groups ( P < .001 ) but no significant differences between PUI and EndoVac groups ( P = .06 ) . CONCLUSIONS PUI and EndoVac are more effective than the conventional endodontic needle in delivering irrigant to WL of root canals The usefulness of NaviTip FX , a brush-covered irrigation needle , in endodontic therapy has never been reported . Therefore , the purpose of this investigation was to evaluate the cleaning efficacy of this new brush-covered irrigation needle , the NaviTip FX .  Thirty single-rooted teeth were r and omly divided into two equal groups and instrumented using the crown-down technique with 0.04 taper ProFile . Following each file use , the canals were irrigated with 1 ml of 5.25 % NaOCl using the NaviTip FX needle for group 1 or using the same needle without the brush for group 2 . At the end of instrumentation , the roots were cut longitudinally and each half was divided into three equal parts . The specimens were then routinely prepared for scanning electron microscopic evaluation . The results showed that using the NaviTip FX produced cleaner coronal thirds of instrumented root canals compared to the control group . On the other h and , the middle and apical thirds were not statistically significantly different between the two groups . Further development of this irrigation technique to improve cleanliness of the apical and middle thirds is required before the NaviTip FX can be recommended for routine use during root canal therapy AIM To compare the efficacy of three irrigation protocol s using an established ex vivo bio-molecular film model . METHODOLOGY Thirty human teeth with single straight canals were r and omly allocated to three groups [ static , manual-dynamic , automated-dynamic ( RinsEndo ] ; each with a sub-group ( n = 5 ) for needle position at 4 or 10 mm short of the working length ( WL ) . The root canals were prepared to apical size 40 , taper 0.08 . The teeth were split longitudinally into two halves and a st and ard coat of stained-collagen was applied to the canal surfaces . The re-assembled teeth were irrigated using one of the protocol s with the irrigation needle at one of two positions . Digital images of the canal surfaces , before and after irrigation with 18 mL of 2.5 % NaOCl , were used to score surface coverage with stained-collagen using image-analyses ( ipWin4 ) . The data were analysed using linear regression models . RESULTS The canal area covered with stained-collagen was significantly ( P < 0.001 ) less after dynamic irrigation ( manual/automated ) compared with static irrigation ; but automated-dynamic irrigation was significantly ( P = 0.037 ) less effective than manual-dynamic irrigation . The ' orientation of needle port ' , ' corono-apical level of canal ' and ' apical extent of needle placement ' were significant ( P < 0.001 ) factors influencing efficacy of irrigation . Residual collagen was most evident in the coronal third . Deeper penetration of the needle tip result ed in significantly ( P < 0.001 ) more effective collagen removal . CONCLUSIONS Automated-dynamic irrigation was significantly more effective ( 16 % ) than static irrigation but significantly less effective ( 5 % ) than manual-dynamic irrigation . Irrigation was more effective ( 7 % ) when the needle was placed closer to WL Background Root canal irrigation carries a risk of extrusion of irrigant into the periapical tissues which can be associated with pain , swelling , and tissue damage . Studies have shown less extrusion with sonic or apical negative pressure devices compared with syringe and side-port needle or passive ultrasonic irrigation with continuous irrigant flow . This study aim ed to evaluate the effectiveness of the EndoVac irrigation system , regarding 1 ) debris removal and 2 ) the control of apically extruded irrigating solution . Methods Fifty extracted human single-rooted teeth were used in this study . The teeth were then r and omly divided into three experimental groups according to the type of irrigation used and one control group . In group 1 , irrigation was performed using the EndoVac irrigation system . In group 2 , irrigation was performed using a 30-gauge , tip-vented irrigation needle . In group 3 , irrigation was performed using a 30-gauge , side-vented irrigation needle . The control group received instrumentation with no irrigation to serve as a control for cleaning efficiency . Root canal instrumentation was performed using the Profile NiTi rotary system with a crown-down technique . All of the experimental teeth were irrigated with the same amount of 5.25 % sodium hypochlorite . The amount of extruded irrigating solution was then measured by subtracting the post-instrumentation weight from the pre-instrumentation weight using an electronic balance . The cleanliness of debris removal was evaluated using scanning electron microscopy . Results EndoVac irrigation had the least amount of extrusion followed by the side-vented and tip-vented method . The difference between the groups was statistically significant ( P < 0.01 ) . As for the cleaning results , the debris collection in the EndoVac and tip-vented groups was the least in the apical third . In the control and the side-vented groups , the debris was the greatest in the apical third , but this difference was not significant among the three experimental groups . Conclusions The EndoVac irrigation system extruded significantly less irrigant solution than either needle irrigation system . Debris collection was the least in the apical third for the EndoVac irrigation system . No significant difference was found in the cleaning efficiency among the three irrigation systems
IATs improve intracanal cleanliness across a substantial portion of the canal , and therefore , their use is recommended throughout root canal preparation .
AIMS To establish whether irrigant activation techniques ( IATs ) result in greater intracanal smear layer and debris removal than conventional needle irrigation ( CNI ) .