Micro–computed Tomographic Assessment of the Residual Filling Volume,Apical Transportation,and Crack Formation after Retreatment with Reciproc and Reciproc Blue Systems in Curved Root Canals

IntroductionThe purpose of the present study was to evaluate the remaining root canal filling material, apical transportation, and crack formation after retreatment with M-Wire Reciproc (VDW GmbH, Munich, Germany) and Reciproc Blue (VDW GmbH) systems in curved root canals.MethodsTwenty-six mandibular first and second molars with mesial roots that had 2 separate canals with angles between 20° and 40° were selected for this study. The root canals were prepared with M-Wire Reciproc size 25 instruments (VDW GmbH), and they were filled with gutta-percha and AH Plus sealer (Dentsply Sirona, Tulsa, OK). The samples were randomly divided into 2 groups (n = 13 each) according to the retreatment system used: an M-Wire Reciproc group and a Reciproc Blue group. The canals were retreated up to instrument size 25 and then to size 40 in both groups. After the retreatment procedures, the residual filling material volume, apical transportation, and crack formation were assessed using micro–computed tomographic imaging.ResultsThere were no significant differences between the groups in the amount of residual filling material (P > .05). The apical canal transportation values were significantly higher in the M-Wire Reciproc group than in the Reciproc Blue group at 1 mm. No significant differences were observed between the groups at any of the other levels with regard to apical transportation (P > .05) The new uncompleted and completed cracks were observed in both groups. There were no statistically significant differences between the groups in terms of crack and fracture formation (P > .05).ConclusionsThe Reciproc Blue system is as effective as the M-Wire Reciproc system in terms of the retreatment of the curved mesial roots of mandibular molars. However, the formation of new uncompleted and completed cracks was found during the retreatment procedures.     

The supplementary use of XP-endo Finisher R after Reciproc enhances the removal of a bioceramic sealer in oval root canals

This study compared the performance of Reciproc and Reciproc Blue endodontic files in retreatment time and re-establishment of apical patency, plus removal of a bioceramic sealer from the canal surface with the supplementary use of the XP-endo Finisher R. Following preparation, slightly curved oval root canals in mandibular incisors were filled using a corresponding gutta-percha point and a bioceramic sealer. Apical patency achievement was assessed and the time required to reach the original working length was recorded. The samples were split longitudinally and were photographed to assess the material remaining on the canal walls. No significant differences were observed regarding patency achievement or retreatment times when comparing Reciproc and Reciproc Blue. Significant less material remained on the canal walls when Reciproc was followed by XP-endo compared with Reciproc alone, and when the data for Reciproc and Reciproc Blue were pooled.     

Efficacy of a thermally treated single file compared with rotary systems in endodontic retreatment of curved canals: a micro-CT study

Objectives

This study aimed to compare WaveOne Gold with ProTaper and RaCe systems regarding remaining filling material, apical transportation (AT), and working time (WT) after (i) filling removal and (ii) shaping of curved canals.

Methods

Thirty mesiobuccal canals of maxillary molars were prepared and filled. After 30 days, they were randomly assigned into three groups (n = 10), according to the instruments used for filling removal and shaping, respectively: WOG—WaveOne Gold Primary and Medium; PTG—ProTaper Retreatment and ProTaper Next; RCG—D-RaCe and RaCe. Micro-CT analysis assessed the residual filling material and AT. WT was recorded. Data were statistically analyzed (α = .05).

Results

There was no significant difference between groups in the amount of filling material at any evaluated moment (P > .05). All groups presented low AT values. The WT was similar in all groups in filling removal (P > .05), and in shaping step WOG was faster than PTG and RCG (P < .05).

Conclusions

Neither system could completely remove the filling material. The instruments evaluated were safe and the reciprocating system was faster than the rotary systems in shaping the canals.

Clinical relevance

This study provided consistent information on filling material removal capacity of WaveOne Gold. Considering that all tested systems were safe, WaveOne Gold may be an alternative with cost-effectiveness and shorter learning curve for endodontic retreatment.

     

Dentinal tubule penetration of AH Plus,BC Sealer and a novel tricalcium silicate sealer: a confocal laser scanning microscopy study

Objectives

The aim of this in vitro study was to assess the dentinal tubule penetration of three different sealers, AH Plus, BC Sealer and a novel tricalcium silicate sealer (NTS).

Materials and methods

Ninety-six human maxillary central incisors were divided into three experimental groups (n = 32) and were filled with gutta-percha using a single-cone technique in conjunction with one of the three sealers: AH Plus, BC Sealer or NTS. The roots in each group were cross-sectioned at 1 and 5 mm from the root apex, and the surfaces were examined under confocal laser scanning microscopy (CLSM). The sealer penetration depths were measured at their maximum depths and at four circumferential depths (12, 3, 6 and 9 o’clock) and were evaluated using ImageJ software (ImageJ, NIH).

Results

The maximum and mean penetration depths were significantly higher at 5 mm compared to 1 mm from the apex in the AH Plus (p < 0.001), BC Sealer (p < 0.001) and NTS groups (p < 0.001). No significant difference was observed between the groups at 1 mm for both parameters. The maximum and mean penetration depths were significantly lower at 5 mm for AH Plus compared with the other two groups (p = 0.012).

Conclusions

Within the study limitations, the BC Sealer and NTS demonstrated better tubule penetration results than the AH Plus sealer.

Clinical relevance

Although no study has confirmed a relationship between the penetration depth of root canal sealers and the prevention of apical periodontitis, dentinal tubule sealer penetration may improve obturation quality.

     

3-dimensional Ability Assessment in Removing Root Filling Material from Pair-matched Oval-shaped Canals Using Thermal-treated Instruments

IntroductionThe purpose of this study was to evaluate the ability of the XP-endo Shaper instrument (FKG Dentaire, La Chaux-de-Fonds, Switzerland) during the removal of root fillings from oval-shaped canals. M-Wire Reciproc and Reciproc Blue systems (VDW, Munich, Germany) were used as reference instruments for comparison, and micro–computed technology was used as an analytical tool.MethodsThirty mandibular incisors with oval-shaped canals were matched based on similar anatomic features of the canal (eg, volume, aspect ratio, and 3-dimensional configuration) after scanning procedures. The canals were prepared with M-Wire Reciproc R25 instruments and filled with gutta-percha and AH Plus sealer (Dentsply DeTrey, Konstanz, Germany) using the continuous wave of condensation technique. Then, the sample was allocated into 3 experimental groups (n = 10) according to the retreatment protocol used: M-Wire Reciproc, Reciproc Blue, and XP-endo Shaper. M-Wire Reciproc R25, Reciproc Blue R25, and XP-endo Shaper instruments were used to remove the root fillings. Apical enlargement was performed with M-Wire Reciproc R40, Reciproc Blue R40, and BioRace BR5 (FKG Dentaire) instruments. Each sample was scanned after each endodontic procedure. The volume of remaining root filling material was quantified before and after apical enlargement. The percentage volumes of root filling reduction in relation to the instrumented canals at both time points (before and after apical enlargement) were calculated and considered for statistical analysis. Data were analyzed statistically with a significance level of 5%.ResultsReciproc Blue presented significantly lower removal of filling material compared with the XP-endo Shaper (Tukey test, P < .05). No difference was detected either between M-Wire Reciproc and Reciproc Blue (Tukey test, P > .05) or M-Wire Reciproc and XP-endo Shaper (Tukey, P > .05). The increase of apical enlargement significantly improved the removal of root fillings from the root canals (P < .05); this effect was similar for all systems (time point × file system, P > .05).ConclusionsThe XP-endo Shaper instrument showed a higher percentage of root filling removal, but no differences were observed comparing M-Wire Reciproc with the XP-endo Shaper or Reciproc Blue. The increase of apical enlargement improved the removal of root fillings in all groups. None of them was able to render root canals completely free from root fillings.     

Comparative evaluation of cone beam CT and micro-CT on blooming artifacts in human teeth filled with bioceramic sealers

Aim

To assess blooming artifacts caused by root canal sealers in CBCT images compared with those that appeared in micro-CT scan images used as references.

Materials and method

Thirty freshly extracted human mandibular central incisors were used. Root canals were prepared with nickel titanium files with an ISO size 40/0.06 taper and filled with a single cone (40/0.06 taper) and three different sealers. The samples were divided into the following three groups with 10 roots each: (I) AH Plus sealer; (II) Sure Seal Root; and (III) Total BC sealer. Teeth were scanned with the same voxel sizes (0.2 mm) in different CBCT devices and the micro-CT images were acquired as reference images.

Results

Significantly different results in terms of blooming artifacts were detected between CBCT and micro-CT images, as well as among the CBCTs images. The canals filled with AH Plus sealer showed more blooming artifacts than those filled with bioceramic sealers (p < 0.05). Additionally, the worst blooming artifact was observed when the images were acquired with lower kilovoltage peak.

Conclusion

The appearance of blooming artifacts is dependent on sealer and CBCT, and their effects are significantly worse than they are in micro-CT images. The differential effect of different sealers and distinct CBCT protocols should be further investigated to enable the use of bioceramic sealers without a significant impact on post-treatment imaging.

Clinical relevance

Root canal sealers showed a different extent of blooming artifact in CBCT images. Hence, researchers and clinicians should be aware of these artifacts before conducting endodontic evaluations using CBCT images.

     

Efficacy of Different Solvents for Achieving Patency in Teeth Obturated Using Bioceramic Sealer

IntroductionThe retreatment of teeth obturated with bioceramic sealers has been shown to be challenging. The purpose of this study was to compare the efficacy of 10% formic acid (FA), 20% hydrochloric acid (HCl), and chloroform for achieving patency in teeth obturated with a bioceramic sealer.MethodsForty-five extracted single-canal teeth were instrumented and obturated 1.5 mm short of the working length using gutta-percha and EndoSequence BC Sealer (Brasseler USA, Savannah, GA). Two weeks later, gutta-percha was removed, and apical patency was attempted with a 10 C-file and a solvent (FA, HCl, or chloroform). The time to gain patency through EndoSequence BC Sealer was recorded. Five additional teeth were irrigated with the solvents, and scanning electron microscopy was used to evaluate the effect of solvents on the dentin. The Kruskal-Wallis and Mann-Whitney tests were used for statistical analysis.ResultsPatency was achieved in all canals, except for 1 in the chloroform group. Regarding the time to achieve patency, no significant difference was noted between chloroform and FA (P > .05). However, there was a significant difference between chloroform and HCl (P < .05) and between FA and HCl (P < .05). The erosion of dentinal tubules was more evident when HCl was used compared with the other irrigants.ConclusionsTwenty percent HCl was superior to 10% FA and chloroform in achieving patency in teeth obturated with EndoSequence BC Sealer. Regardless of the solvent used, patency may be achieved for most of the cases obturated with gutta-percha and EndoSequence BC Sealer.     

In vitro evaluation of the antibacterial effect of four root canal sealers on dental biofilms

Objectives

To dynamically evaluate the effect of four root canal sealers on the killing of biofilms within dentinal tubules.

Materials and methods

Dentin blocks were prepared for infection of the dentinal tubules. Enterococcus faecalis VP3-181 and multi-species bacteria from two donors were cultured. After 3 days of incubation, the infected dentin specimens were rinsed with sterile water for 1 min and subjected to treatment. Additionally, multi-species bacteria from donor 1 were incubated for 3 weeks to allow biofilm maturation and then the specimens were subjected to treatment. Gutta-percha-treated dentin specimens comprised the control group. A root canal sealer (bioceramic sealers: EndoSequence BC Sealer, ProRoot Endo Sealer, or GuttaFlow Bioseal; and a traditional silicone-based sealer: Guttaflow 2) was spread onto the canal walls of the dentin. The specimens were examined with confocal laser scanning microscopy at 7, 30, or 60 days.

Results

In the 3-day-old biofilm group, the proportion of killed bacteria decreased significantly from the first 7 days of treatment to 60 days of treatment for all sealers (p?<?0.05). In the 3-week-old biofilm group, 60 days of exposure to bioceramic sealers resulted in more significant dead bacteria than 7-day exposures of the biofilms (p?<?0.05). Bioceramic sealers were more effective in killing bacteria than the GuttaFlow 2 sealer (p?<?0.05).

Conclusions

Calcium silicate–based sealers showed good antimicrobial effects against biofilms within dentinal tubules, especially in the first week in young biofilms. There is no substantive antibacterial activity observed for the examined root canal sealers against young dentinal tubule biofilms.

Clinical relevance

The bioceramic root canal sealers examined demonstrate minimal additional antibacterial effects after long-term exposure to young biofilms.

     

Effect of Ultrasonic Activation of Endodontic Sealers on Intratubular Penetration and Bond Strength to Root Dentin

IntroductionThis study aimed to evaluate the effect of ultrasonic activation (UA) of endodontic sealers on dentin tubule penetration and the bond strength to root dentin.MethodOne hundred single-rooted teeth were prepared with 40.06 nickel-titanium instruments and divided into 2 groups: with or without UA. Three resin-based sealers (MTA Fillapex [Angelus Dental Solutions, Londrina, PR, Brazil], Sealer Plus [MK Life Medical and Dental Products, Porto Alegre, RS, Brazil], and AH Plus [Dentsply, DeTrey GmbH, Konstanz, Germany]; n = 20) and 2 calcium silicate–based sealers (Sealer Plus BC [MK Life Medical and Dental Products] and EndoSequence BC [Brasseler, Savannah, GA], n = 20) were used and subdivided (n = 10) according to the protocols. Fluo-3 (Thermo Fisher Scientific, Waltham, MA) and rhodamine B dyes were added to the calcium silicate- and resin-based sealers, respectively. In the UA groups, the activation was performed for 40 seconds followed by lateral compaction. Samples were transversely sectioned to evaluate the dentin tubule penetration and the bond strength to root dentin. The penetration data were analyzed with the Student t test, 1-factor analysis of variance, and Bonferroni tests. Bond strength was evaluated using the Student t test, Kruskal-Wallis, and Dunn post hoc test.ResultsResin-based sealers showed the highest tubule penetration without UA (P < .05). UA significantly enhanced MTA Fillapex and Endosequence BC dentin tubule penetration (P < .05). AH Plus and Sealer Plus BC improved their bond strength to root dentin after UA (P < .05). AH Plus/UA, Sealer Plus/UA, and Sealer Plus BC/UA presented the highest bond strength values (P < .05). Adhesive failures were predominant in all groups regardless of the use of ultrasound.ConclusionsUA interferes with tubule penetration and the bond strength to root dentin of resin- and calcium silicate–based sealers.     

Postoperative pain after the removal of root canal filling material using different techniques in teeth with failed root canal therapy: a randomized clinical trial

Objectives: This study evaluated the intensity and duration of postoperative pain after the removal of root canal filling material in retreatment procedures of upper incisor teeth with chronic apical periodontitis, using different techniques.

Materials and methods: One hundred and thirty-five patients requiring retreatment of upper incisor teeth with chronic apical periodontitis were included in the study. The patients were assigned to three groups of 45 patients, according to the method used to remove old canal filling material. In group 1, canal filling material was removed using hand files. In group 2, the canal filling material was removed with ProTaper universal retreatment (PTUR) instruments. In group 3, Reciproc instruments were used to remove canal filling material. Teeth were then medicated with calcium hydroxide and sealed using temporary filling material. The presence of postoperative pain was assessed after 6, 12, 24, 48 and 72?h, 7 days, and finally after 10 days.

Results: In all time intervals, except for 72?h, 7 days and 10 days, group 1 participants reported more intense postoperative pain than those in groups 2 and 3 (p?=?0.02). In all time intervals, there was no difference in the pain scores between groups 2 and 3 (p?=?0.08). In all groups, the intensity of postoperative pain decreased over time. The required time to remove canal filling material was less for the Reciproc group compared to the hand and ProTaper retreatment groups (p?=?0.032).

Conclusions: Hand files caused greater postoperative pain after non-surgical endodontic retreatment (NSER) of upper incisor teeth with chronic apical periodontitis compared to the ProTaper retreatment and Reciproc files.     

Efficiency Evaluation of Various Solvents in Retreatment of Endodontic Filling in Extracted Teeth

ObjectivesThe aim of this study was to evaluate the retreatment duration and efficacy of eucalyptol and tea tree oil in engine driven and manual retreatment of epoxy resin based endodontic filling in extracted human teeth.Methods and materialsSixty human single rooted teeth were randomly divided into two groups. The first group was prepared using hand files, and the second one using Reciproc system. Root canals were filled with gutta-percha points and AH Plus sealer. Retreatment was performed using K-reamers and Hedström files for the first group, and Reciproc instruments for the second group. Each group was divided into two subgroups (n=15) according to the retreatment solvent used (eucalyptol or tea tree oil). Root canals were longitudinaly split and analized with stereomicroscope (15x magnification). The surface of the remaining filling material was measured using an image processing software.ResultsThere were no statistically significant differences in the area of residual filling material among used solvents, nor in applied technique. Retreatment with Reciproc instruments was significantly faster compared to retreatment using hand files. The manual retreatment technique was faster when tea tree essential oil was used as a solvent compared to eucalyptol.ConclusionsAustralian tea tree oil and eucalyptus oil were equally effective in removing endodontic filling material, but none of canals were completely free of the residual filling material. Retreatment with Reciproc instruments was faster compared to retreatment using hand files. The manual retreatment technique is faster when tea tree essential oil is used as a solvent compared to eucalyptol.     

Cyclic Fatigue Resistance of Multiused Reciproc Blue Instruments during Retreatment Procedure

IntroductionRoot canal retreatment procedure may reduce the mechanical resistance of nickel-titanium instruments and increase the frequency of instrument fracture. The aim of the present study was to evaluate the effect of multiuse of Reciproc Blue R25 instruments on cyclic fatigue resistance during retreatment procedure in mandibular molar teeth.MethodsForty-eight Reciproc Blue R25 files were included in the study. In control group, 12 new Reciproc Blue R25 instruments were subjected to cyclic fatigue test by using a stainless steel artificial canal with a 90° angle and 3-mm radius of curvatures. In experimental groups, Reciproc Blue R25 files (n = 12) were used to remove the root canal filling (RCF) material of 1, 2, and 3 molar teeth, respectively. Then cyclic fatigue tests of these 36 instruments were performed. The number of cycles to fracture (NCF) and the length of the fractured fragment were calculated for each instrument. Working time for retreatment procedures was determined in seconds with a digital chronometer. The data were analyzed by using one-way analysis of variance followed by post hoc Tukey test and mixed-effect analysis (P = .05).ResultsNo significant difference was found between NCF values of new and first time used files (P > .05), but NCF values of new and first time used files were significantly higher than those of second and third time used files (P < .05). The second and third time used files revealed no difference (P > .05). As the number of uses increased, the average time for retreatment procedure statistically extended (P < .05).ConclusionsReciproc Blue R25 instrument can be used to remove RCF material of 2 molar teeth. However, because of its decreased NCF values, multiple use over 2 molars may not be suggested.     

Micro–computed Tomographic Assessment of Supplementary Cleaning Techniques for Removing Bioceramic Sealer and Gutta-percha in Oval Canals

IntroductionThe aim of this study was to conduct a micro–computed tomographic assessment of the effectiveness of 3 supplementary cleaning techniques in reducing the residual volume of gutta-percha and a bioceramic sealer after performing endodontic retreatment procedures in teeth with oval canals.MethodsThirty-six mandibular premolars were instrumented with the ProTaper Next system (instruments X1–X3; Dentsply Maillefer, Ballaigues, Switzerland) and filled with gutta-percha and Bio-C Sealer (Angelus, Londrina, PR, Brazil) using the single-cone technique. The teeth were reinstrumented with the Reciproc R40 instrument (VDW, Munich, Germany) and divided into 3 groups according to the supplementary cleaning technique used (n = 12): ultrasonic-assisted irrigation (UAI), EndoActivator (Dentsply Tulsa Dental Specialties, Tulsa, OK) irrigation (EAI), or the XP-endo Finisher R system (XPR; FKG Dentaire, La Chaux-de-Fonds, Switzerland). Micro–computed tomographic imaging was used to quantify the residual volume of filling material. One-way analysis of variance complemented by the Tukey test was used to perform the statistical analysis (P < .05).ResultsSignificant reductions were obtained in the residual filling material after supplementary cleaning (P < .05). XPR (47.5%) led to significantly greater (P < .05) filling material removal than UAI (16.6%) or EAI (22.6%). The removal values of the 2 latter systems were not significantly different.ConclusionsXPR was more effective than UAI and EAI in removing filling material in mandibular premolars with oval canals. None of the tested supplementary cleaning techniques completely removed the residual filling material.     

三种镍钛器械对弯曲根管成形能力的实验研究

目的 比较Reciproc、Reciproc Blue和Protaper 3种机用镍钛器械在弯曲根管中成形能力的差异,为临床器械选择提供实验依据.方法 选择透明树脂弯曲根管30个,随机分成3组.分别用Reciproc(R组)、Reciproc Blue(RB组)和Protaper(P组)机用镍钛锉进行根管预备,记录预备...     

The Antimicrobial Effect of Bioceramic Sealer on an 8-week Matured Enterococcus faecalis Biofilm Attached to Root Canal Dentinal Surface

IntroductionThe aim of this study was to test the antibacterial activity of bioceramic sealer in comparison with AH Plus (Dentsply International Inc, York, PA) on 8-week-old Enterococcus faecalis biofilms attached to root canal surfaces using a dentin infection model.MethodsThe canal surfaces of single-rooted intact extracted teeth were infected by growing E. faecalis biofilms for 8 weeks. AH Plus sealer and EndoSequence BC Sealer (Brasseler USA, Savannah, GA) were placed on the root canal wall of the dentin specimens for 24 hours and 2 weeks in humid conditions at 37°C. Infected samples incubated with no sealers for similar periods were used as the negative controls. Specimens were labeled with fluorescent viability staining, and confocal laser scanning microscopy was used as an assessment tool of the proportions of dead and live bacteria on canal walls after exposure to root canal sealers for the determined times.ResultsEndoSequence BC Sealer killed significantly more E. faecalis in biofilm attached to the canal surfaces when compared with AH plus sealer and control at both time points (P < .05–.0005).ConclusionsEndoSequence BC Sealer exhibited significant antimicrobial capacity in the presence of dentin for up to 2 weeks on an 8-week-old E. faecalis biofilm in comparison with AH Plus sealer.     

2种镍钛器械对根管充填物清除效率比较

目的:比较Mtwo R再治疗锉、Reciproc锉与手动器械在根管再治疗过程中对根管内充填物的清除效率.方法:取45颗离体下前牙,清理根管后,预备至40#.牙胶尖和AH Plus糊剂以冷侧压法充填根管.随机分为3组,分别用手用器械、Mtwo R和Reciproc去除根管内充填材料,收集推出根尖孔的碎屑,称重,记录所用时间.样本沿长轴颊舌向劈开,显微镜下进行观察、评分.采用SPSS 13.0软件包对数据进行统计学分析.结果:3种方法碎屑推出量和管壁清洁度无显著差异(P＞0.05),Mtwo R组和Reciproc组用时更少(P＜0.05).结论:镍钛器械并不能完全清除根管充填物,但可以提高效率.     

The influence of root canal shape on the sealing ability of two root canal sealers

AIM: To evaluate the influence of root canal form on the sealing ability of two root canal sealers. METHODOLOGY: Twenty radiographically confirmed straight and 20 curved root canals were prepared with a stepback hand filing technique. Root canal aberrations created during preparation were determined by the use of double exposure radiographic technique. The prepared canals were filled with lateral condensation of gutta-percha and one or other of two root canal sealers (Pulp Canal Sealer and Sealapex). Leakage along the apical 10 mm of roots was measured with a fluid transport model at 1, 3, 6, 9 and 12-month intervals. RESULTS: There were no statistically significant differences between straight and curved root canals (P > 0.05) for prevalence of root canal transportation. The prevalence of apical transportation was 80% in the straight and 85% in the curved root canals. A complete seal was more frequently observed in straight canals compared with curved canals. Utilizing the pi* index, analysis showed the filling with Sealapex allowed more leakage than Pulp Canal Sealer at 1 year. CONCLUSION: Under the conditions of the study, root canal form influenced short-term sealing ability. In the long-term the seal was affected by the sealer rather than root canal form.     

Effectiveness of a silicon-based root canal sealer for filling of simulated lateral canals

The purpose of this in vitro study was to evaluate the ability of a silicon-based root canal sealer, compared to zinc oxide and eugenol and an epoxy resin-based sealers, for filling of simulated lateral canals. Thirty extracted single-rooted human teeth were selected, conventional access was made and the working length was established 1 mm from the apical foramen. Three simulated lateral canals, one in each root third (coronal, middle and apical) were prepared in both the mesial and distal surfaces of each tooth using a size 15 reamer adapted to a low-speed handpiece. Each root canal was instrumented using ProTaper rotary files up to file F3 at the working length, and then irrigated with 2.5% NaOCl followed by EDTA. The teeth were assigned to 3 groups (n=10), according to the root canal sealer: Roeko Seal (Group 1), Sealer 26 (group 2) and Grossman's sealer (Group 3). Gutta-percha cold lateral condensation technique was performed in all groups. Postoperative radiographs were taken and the images were projected for evaluation of the quality of lateral canal filling. Data were submitted to statistical analysis by Kruskal Wallis test at 5% significance level. The results showed that Grossman's sealer filled a larger number of lateral canals than Roeko Seal (p<0.05) and Sealer 26 (p<0.01). It may be concluded that Roeko Seal silicone-based root canal sealer was not as effective as the Grossman's sealer for filling of simulated lateral canals. The lateral canals localized in the apical third of the root were more difficult to be filled.     

Cyclic Fatigue Resistance of Reciproc Blue and Reciproc Files in an S-shaped Canal

Introduction

This study evaluated the cyclic fatigue resistance (CFR) of Reciproc (R25 and R40; VDW, Munich, Germany) and Reciproc Blue (R25 and R40, VDW) instruments used in an artificial S-shaped canal.