ProFile Rotary Instruments Research Articles

The flaring efficiency of the Profile and Protaper on resin simulated root canals

Forty resin simulated root canals with standardized curvature prepared for thisstudy, divided into four groups ten canals for each group. Thirty canals were preparedwith rotary endodontic instruments, profile 04, profile 04, 06 and protaper, ten canalsfor each type, with slow speed contra angle hand piece (300 rpm) using crown — downtechnique the other l0 canals were prepared with stainless steel k-flexo handinstrument using step — back technique. The total time required for preparation wascalculated. The resin blocks were scanned; the pre-instrumented and post -instrumented images were stored in the computer and superimposed for twodimensional evaluation of canals preparation using Adobe photoshope 8.0 and Coreldraw 9. For the coronal portion the amount of canal substance removed wascalculated at 7mm, 9mm, llmm levels from the working length. For the apicalcurvature the centering ratio was calculated at 2mm and 4mm level from the workinglength. The results showed that the amount of canal substance removed from thecoronal portion by protaper was statistically higher than other groups with statisticallyless ability to stay center in the canal than profile rotary instruments but more abilityto preserve apical curvature than k-flexo hand instruments with less time required forpreparation. K-flexo files showed statistically less amount of canal substance removalat coronal portion and statistically higher centering ratio than other groups, andrequire more time for canals preparation .

The Penetration Ability of Calcium Silicate Root Canal Sealers into Dentinal Tubules Compared to Conventional Resin-Based Sealer: A Confocal Laser Scanning Microscopy Study.

The purpose of this study was to compare the penetration ability of calcium silicate root canal sealers and conventional resin-based sealer using confocal laser scanning microscopy (CLSM). A total of 60 recently extracted single-rooted human premolars were used in this study. The root canals were prepared to a size 40/0.06 taper with ProFile rotary instruments and irrigated with NaOCl and EDTA. After drying all canals, the specimens were randomly divided into three experimental groups (n = 20): Group 1, gutta-percha (GP)/AH Plus with continuous wave compaction; group 2, GP/BioRoot RCS with a single-cone technique; and group 3, GP/Endoseal MTA with a single-cone technique. All experimental samples were sectioned perpendicular to their long axis using a low-speed diamond wheel at the apical, middle, and coronal third levels. The penetration abilities of all samples were evaluated using CLSM. A Kruskal–Wallis analysis and a series of Mann–Whitney U post hoc tests were performed. A higher intensity level was found in the coronal area and a lower intensity level in the apical area in all the experimental groups. The AH Plus group showed higher sum fluorescence intensity in the apical and coronal thirds compared with the BioRoot RCS and Endoseal MTA groups, whereas the BioRoot RCS group showed a higher intensity level in the middle third, similar to the AH Plus group. The maximum sealer penetration depth was low in the apical area and high in the coronal area in the AH Plus and Endoseal MTA groups. In the BioRoot RCS group, maximum sealer penetration was observed in the middle third. In conclusion, there were significant differences in sealer penetration pattern and distance according to the root level and sealer type.

Dynamic Torsional and Cyclic Fracture Behavior of ProFile Rotary Instruments at Continuous or Reciprocating Rotation as Visualized with High-speed Digital Video Imaging

IntroductionThis study examined the dynamic fracture behavior of nickel-titanium rotary instruments in torsional or cyclic loading at continuous or reciprocating rotation by means of high-speed digital video imaging. MethodsThe ProFile instruments (size 30, 0.06 taper; Dentsply Maillefer, Ballaigues, Switzerland) were categorized into 4 groups (n = 7 in each group) as follows: torsional/continuous (TC), torsional/reciprocating (TR), cyclic/continuous (CC), and cyclic/reciprocating (CR). Torsional loading was performed by rotating the instruments by holding the tip with a vise. For cyclic loading, a custom-made device with a 38° curvature was used. Dynamic fracture behavior was observed with a high-speed camera. The time to fracture was recorded, and the fractured surface was examined with scanning electron microscopy. ResultsThe TC group initially exhibited necking of the file followed by the development of an initial crack line. The TR group demonstrated opening and closing of a crack according to its rotation in the cutting and noncutting directions, respectively. The CC group separated without any detectable signs of deformation. In the CR group, initial crack formation was recognized in 5 of 7 samples. The reciprocating rotation exhibited a longer time to fracture in both torsional and cyclic fatigue testing (P < .05). The scanning electron microscopic images showed a severely deformed surface in the TR group. ConclusionsThe dynamic fracture behavior of NiTi rotary instruments, as visualized with high-speed digital video imaging, varied between the different modes of rotation and different fatigue testing. Reciprocating rotation induced a slower crack propagation and conferred higher fatigue resistance than continuous rotation in both torsional and cyclic loads.

Efficacy of Different Irrigation Protocols for Removing Gutta-Percha and Sealer Remnants in Artificial Un-instrumented Areas.

Objective:The purpose of this study was to determine the efficacy of different irrigants and irrigation protocols in the removal of gutta-percha and sealer from simulated un-instrumented areas.Methods:Eighty-four uniradicular teeth were used. After standardizing working length (WL) and preparing the glide path, coronal flaring was performed. The instrumentation phase was completed with ProFile rotary instruments up to size #35 LightSpeed LSX. Roots were split into halves: in one of them, a groove was prepared in the apical 6 mm. In the opposite one, 5 depressions were made (at 2, 4, 6, 8 and 10 mm). Irregularities were filled with AH Plus sealer and flowable gutta-percha. The Efficacy of sodium hypochlorite (NaOCl) and chloroform in removal of material and the effect of positive pressure (PP), passive ultrasonic irrigation (PUI) (one or three cycles) and paper points were analysed with the chi-square test.Results:Delivery by PP did not eliminate the obturator material from any artificial depression. Chloroform, when activated, demonstrated a significant linear trend in the amount of gutta-percha removed at all tested levels (P<0.01). The use of paper points after passive delivery of chloroform increased significantly the removal of gutta-percha in the groove and at 4 and 10 mm (P<0.05). Three cycles of PUI and chloroform showed significantly fewer remnants of gutta-percha (P<0.01).Conclusion:Positive pressure was not effective in the removal of obturator materials with any of the tested irrigants. Chloroform delivered by PP in combination with paper points obtained a better cleaning efficacy, although its activation using PUI for three cycles of 20 s showed the best cleanliness.

Comparative evaluation of efficacy and effectiveness of profile rotary instruments in conjugation with solvent for retreatment of resilon and gutta-percha: An In vitro study

Aim: The aim is to determine the effectiveness of rotary instrumentation (ProFile 0.06 tapered rotary NiTi instruments) in conjugation with solvent (chloroform) in the removal of resilon compared to gutta-percha during root canal retreatment. Materials and Methods: Sixty recently extracted human mandibular permanent premolars with straight roots with single canals were used. Decoronation of samples done at cementoenamel junction using the diamond disk. The length of each canal was determined with a size 15 K file and canals were instrumented using a crown down technique with ProFile 0.06 tapered NiTi rotary instruments. Irrigation done followed by obturation. Result and Conclusion: Statistical evaluation was done using paired t-test (P < 0.05) which showed that the samples obturated with resilon showed significantly better results at the apical third when compared to samples obturated with gutta-percha and the time required for Group 2 is significantly less than Group 1.

Comparison of the shaping ability of RaCe, FlexMaster, and ProFile nickel-titanium instruments in severely curved root canals.

BackgroundThis in vitro study compared the shaping ability of RaCe, FlexMaster, and ProFile rotary nickel-titanium instruments in severely curved root canals of extracted teeth.Material and MethodsSixty maxillary molars with curvatures ranging from 25° to 65° were embedded in a muffle system and portioned into five horizontal sections (thickness 1.2 mm), starting from the apex. Canals were divided into three groups (n = 20, each) and were prepared with RaCe, FlexMaster, or ProFile rotary nickel-titanium instruments and the TriAuto ZX handpiece using a crown-down preparation technique. We evaluated the difference between pre- and postoperative root canal cross-sections, loss of working length, instrument failure, and preparation time. The root canal area before and after the intervention was determined using an area-measuring software. The data were analyzed statistically using a one-way ANOVA followed by a Kruskal-Wallis multiple-comparison Z-value test.ResultsSpecimens treated with FlexMaster showed the greatest change from preoperative cross-sections, followed by RaCe and ProFile. The cross-sectional changes induced by RaCe and FlexMaster preparation differed significantly from those produced by ProFile. Loss of working length, instrument failure, and preparation time did not differ significantly between the groups.ConclusionsRoot canal preparation with the three instruments did not lead to any significant alteration of the original root anatomy or working length. Thus, we conclude that RaCe, FlexMaster, and ProFile instruments are of comparable efficiency and usefulness in the preparation of severely curved root canals. Key words:Endodontics, root canal preparation, rotary, extracted teeth, nickel-titanium.

Effect of time on electronic working length determination with a novel endodontic module in preclinical endodontic training

Aim: To evaluate electrical conductivity of the medium provided with ModuPRO endodontic modules, and compare it with those of alginate and vinyl polysiloxane impression materials over varying time intervals. Materials and Methods: A 24 Real Endo-t teeth were mounted in the ModuPRO Endo™ modules using three different mounting media [Groups A (Apex Putty), B (alginate), C (extra-light body vinyl polysiloxane)]. The working lengths were predetermined by microscopy, and the root canals were prepared with ProFile rotary instruments before mounting. Working lengths were checked with an electronic apex locator at 24 and 48 hours; 1, 4, and 6 weeks; and 6 months. Data were analyzed using one-way analysis of variance (ANOVA), the Tukey-Kramer multiple comparison tests, and the Wilcoxon Signed Rank Sum test, with significance set at P Results: Group C showed higher measurements and significant differences from groups A and B for up to 6 weeks (P 0.05). After 6 months, all groups showed significantly higher working lengths from those predetermined, but no statistically significant differences were observed among them (P > 0.05). For all groups, differences from predetermined working lengths were lowest at the 1-week interval. Conclusions: Both alginate and the Apex Putty can be used for determining the working lengths using an apex locator over a longer time period. Our study has shown that ModuPRO Endo™ modules, along with the Apex Putty, are effective tools for teaching working length determination with apex locators in preclinical endodontic training.

Percentage exposure of root dentin collagen after application of two irrigation protocols with manual or rotary instrumentation and two methacrylate resin-based sealers.

To compare the percentage of collagen exposed in dentin root thirds after two irrigation protocols with manual or rotary instrumentation using two methacrylate resin-based sealers. Forty-eight single-root human teeth were prepared with manual (n = 24) or nickeltitanium ProFile rotary (n = 24) instrumentation, using 5% NaOCl between instruments and 5 ml 17% EDTA as final irrigant or 20% citric acid + 2% chlorhexidine (CHX) between instruments and as the final irrigant. RealSeal or EndoREZ were used as filling materials. One 1-mm slice per third was abraded and stained with Masson's trichrome method. Mean exposed collagen values were obtained in four areas from each section (at 60X magnification) and a complete factorial ANOVA was used to analyze the influence of the study variables. Non-parametric Mann-Whitney's test was used to compare groups. Differences with p < 0.05 were considered significant. A significantly higher percentage of collagen was exposed in all thirds with the use of the 20% citric acid + 2% CHX protocol with rotary vs manual instrumentation, but percent collagen exposed did not differ as a function of the filling material. After the 5% NaOCl + 17% EDTA protocol, the percentage of collagen exposed did not differ between rotary and manual instrumentation but was higher with the use of RealSeal. The highest percentage exposure of collagen was with 20% citric acid + 2% CHX using rotary instrumentation, regardless of the filling material.

Dentinal defects before and after rotary root canal instrumentation with three different obturation techniques and two obturating materials

Aim:To evaluate the role of rotary root canal instrumentation followed by obturation with three different techniques and two different materials on the incidence of dentinal defects.Materials and Methods:One hundred and sixty mandibular premolars were divided into eight groups (n = 20). Group I was left untreated and served as control. The other seven groups were prepared with profile rotary instruments till #40.06 taper. After preparation, group II was left unfilled, groups III, IV, and V were obturated with Gutta-percha and AH Plus sealer using passive technique, lateral compaction and warm vertical compaction, respectively. Groups VI, VII, and VIII were obturated with Resilon and Realseal sealer using passive technique, lateral compaction, and warm vertical compaction, respectively. Roots were then sectioned at 3, 6, and 9 mm from the apex and inspected under a stereomicroscope (50×) for dentinal defects. Chi-square test was performed to compare the incidence of dentinal defects between the groups (P < 0.05).Results:The unprepared control group had no dentinal defects. The instrumentation group (group II) and the obturation group (groups III-VIII) showed significantly more defects than the uninstrumented control group (group I) (P < 0.001). There was no significant difference between the root canal obturating techniques (group III-VIII) when compared with the instrumentation group (group II). On inter group comparison among the obturation groups the number of defects after lateral compaction with Gutta-percha (group IV) was significantly larger than passive Gutta-percha obturation (group III) (P < 0.05).Conclusions:The results suggest that root canal instrumentation significantly influenced the incidence of dentinal defects or fracture. Dentinal defects were more significantly attributed to the role of root canal instrumentation rather than the type of obturation technique or material. Lateral compaction with Gutta-percha significantly produces more defects than passive Gutta-percha obturation.

Comparison of the Self-Adjusting File with Rotary and Hand Instrumentation in Long-oval–shaped Root Canals

IntroductionThe aim of this study was to compare the root canal debridement ability of the self-adjusting file (SAF) with ProFile rotary (PF) and hand filing (HF) instrumentation in long-oval–shaped canals. MethodsExtracted human teeth (n = 30) were selected on the basis of a root canal ratio of ≥2.5:1 measured 5 mm from the root apex. Each group (n = 10) was matched with regard to the average root canal ratio. Canals were filled with a radiopaque contrast medium (Vitapex) and instrumented by using SAF, PF, or HF with 20 mL of saline irrigation. Teeth receiving irrigation alone served as controls. Preoperative and postoperative radiographs were taken and submitted to digital subtraction, and the percentage reduction of contrast medium was quantified at 0–5 mm and >5–10 mm from the apex. Values were compared by using 1-way analysis of variance and unpaired t tests. ResultsIn the 0- to 5-mm segment, the SAF, PF, and HF removed 80.6% ± 14.1%, 84.2% ± 7.7%, and 76.5% ± 10.2% of the contrast medium, respectively (P > .05). In the >5-to 10-mm segment, the SAF, PF, and HF removed 75.5% ± 10.8%, 72.3% ± 12.0%, and 60.9% ± 11.3% of the contrast medium, respectively, with significantly more material removed by SAF compared with HF (P < .05). There was significantly more contrast medium removed by using combined instrumentation and irrigation compared with irrigation alone (P < .01). ConclusionsAll 3 techniques removed contrast medium equally well from the 0-to 5-mm segment of long-oval–shaped canals. The SAF performed significantly better than hand filing in the >5-to 10-mm canal segment.

Effect of root canal curvature on the failure incidence of ProFile rotary Ni-Ti endodontic instruments

To investigate the effect of root canal curvature on the failure incidence and fracture mechanism of ProFile rotary Ni-Ti endodontic instruments. Three hundred mesial root canals of mandibular molars were instrumented using the ProFile system in a crown-down technique up to size 25 0.06 taper. Root canals were classified according to the angle and radius of curvature to: straight (group A: 0 + 10°, radius 0 mm), moderately curved (group B: 30 ± 10°, radius 2 ± 1 mm) and severely curved (group C: 60 ± 10°, radius 2 ± 1 mm). After each use, instruments were cleaned ultrasonically and autoclaved. Instruments that prepared 20 root canals, fractured or were plastically deformed without fracture were retrieved and substituted. Kaplan-Meier estimator was used for survival analysis and post hoc test for determination of significant differences (a=0.05). All fractured instruments were subjected to fractographic analysis under SEM, and all used instruments were viewed under the metallographic microscope. Regardless of the size of instrument, fracture and overall failure were significantly more frequent (P<0.05) in group C. SEM examination of the fracture surfaces revealed mainly the characteristic pattern of ductile failure, whereas examination under the metallographic microscope revealed no sign of cracks. The abruptness of root canal curvature negatively affected the failure rate of ProFile rotary Ni-Ti instruments. The fractographic results confirmed that failure of Ni-Ti files was caused by a single overload during chemomechanical preparation.

Comparison of apical transportation and change of working length in K3, NRT AND PROFILE rotary instruments using transparent resin block

Objectives: The purpose of this study is to compare the apical transportation and working length change in curved root canals created in resin blocks, using 3 geometrically different types of Ni-Ti files, K3, NRT, and Profile. Materials and Methods: The curvature of 30 resin blocks was measured by Schneider technique and each groups of Ni-Ti files were allocated with 10 resin blocks at random. The canals were shaped with Ni-Ti files by Crown-down technique. It was analyzed by Double radiograph superimposition method (Backman CA 1992), and for the accuracy and consistency, specially designed jig, digital X-ray, and CAD/CAM software for measurement of apical transportation were used. The amount of apical transportation was measured at 0, 1, 3, 5 mm from 'apical foramen - 0.5 mm' area, and the alteration of the working length before and after canal shaping was also measured. For statistics, Kruskal-Wallis One Way Analysis was used. Results: There was no significant difference between the groups in the amount of working length change and apical transportation at 0, 1, and 3 mm area (p = 0.027), however, the amount of apical transportation at 5 mm area showed significant difference between K3 and Profile system (p = 0.924). Conclusions: As a result of this study, the 3 geometrically different Ni-Ti files showed no significant difference in apical transportation and working length change and maintained the original root canal shape.

Apical sealing of root canal fillings performed with five different endodontic sealers: analysis by fluid filtration

ObjectivesTo evaluate the sealing ability of five root canal sealers, including two experimental cements (MBP and MTA-Obtura) using the fluid filtration method. Material and MethodsTeeth were divided into 5 study groups: G1-AH Plus; G2-Acroseal; G3-Sealapex; G4-MBP; G5-MTA-Obtura; and two controls. Chemical-mechanical preparation was performed with ProFile rotary nickel-titanium instruments 1 mm short of the apical foramen. The sealing ability was evaluated by fluid filtration at 15, 30, and 60 days. ResultsThe statistical analysis showed significant difference between the materials at different periods (p<0.05). AH Plus and MBP had similar leakage values at 15 and 60 days, alternating with significant reduction at 30 days, while the other materials showed progressive increase in leakage values. Acroseal and Sealapex presented the best results at 15 days and the worst at 60 days. ConclusionsAll sealers evaluated presented fluid leakage, with AH Plus and MBP showing the best results at the end of the experimental period. Acroseal, Sealapex, and MTA-Obtura presented increase in leakage values at longer observation periods.

Effect of aquatine endodontic cleanser on smear layer removal in the root canals of ex vivo human teeth

ObjectivesThe purpose of this study was to measure and compare the root canal cleanliness and smear layer removal effectiveness of Aquatine Endodontic Cleanser (Aquatine EC) when used as an endodontic irrigating solution in comparison with 6% sodium hypochlorite (NaOCl).Material and MethodsForty-five human teeth were randomly allocated to five treatment groups; the pulp chamber was accessed, cleaned, and shaped by using ProTaper and ProFile rotary instrumentation to an ISO size #40. The teeth were then processed for scanning electron microscopy, and the root canal cleanliness and removal of smear layer were examined.ResultsThe most effective removal of smear layer occurred with Aquatine EC and NaOCl, both with a rinse of EDTA.ConclusionsAquatine EC appears to be the first hypochlorous acid approved by the FDA to be a possible alternative to the use of NaOCl as an intracanal irrigant. Further research is needed to identify safer and more effective alternatives to the use of NaOCl irrigation in endodontics.

Endodontic retreatment Effectiveness of nickel - titanium rotary instruments versus stainless steel hand files: An in vitro study

The purpose of this study was to compare the effectiveness in retreating gutta percha obturated root canals using Profile, with and without the aid of chloroform, to hand files with chloroform. Also the time required for retreatment with each of the methods was determined and compared. A total of thirty extracted maxillary and mandibular canines were distributed to 3 groups of 10 teeth. Group A - Conventional hand files with chloroform. Group B -Profile rotary instruments with chloroform. Group C - Profile rotary instruments alone without chloroform. The teeth were instrumented with k-type files and filled using lateral condensation technique with gutta-percha and AH plus sealer. Retreatment was carried out using Gates Glidden drills and the test instruments. Teeth were split longitudinally, photographed and subjected to software Autocad 2005 to measure remaining gutta-percha/sealer on the root canal wall. Profiles without chloroform, showed less obturation material when compared to Hand files with chloroform and Profiles with chloroform respectively but without any significant difference. Profiles with chloroform took the least time for removing gutta percha/sealer. The study demonstrated that all the retreatment techniques used, resulted in some amount of residual filling material in root canal space after retreatment. It was impossible to achieve completely clean canals.

Comparison of removed dentin thickness with hand and rotary instruments.

The aim of this study was to evaluate the amount of dentine removed after canal preparation using stainless steel (SS) hand instruments or rotary ProFile instruments. Thirty-six extracted human teeth with root canal curvatures less than 30º were embedded in clear polyester resin. The roots were cut horizontally at apical 2, 4 and 7 mm. Dentin thickness was measured at each section and the sections were accurately reassembled using a muffle. Root canals were randomly prepared by SS hand instruments or rotary ProFile instruments. Root sections were again separated, and the remaining dentin thickness was measured. Mann-Whitney U and t tests were performed for analytic comparison of the results. The thickness of removed dentin was significantly different between the two used methods (P<0.05). Significantly greater amounts of dentin was removed mesially in all sections in hand instrumentation group (P<0.001). ProFile rotary instrumentation prepares root canals with a greater conservation of tooth structure.

A comparative scanning electron microscopic study of the effect of three different rotary instruments on smear layer formation

The aim of this study was to evaluate the effect of RaCe, FlexMaster and ProFile rotary instruments on smear layer formation by scanning electron microscopy. Eighty-four caries-free freshly extracted human single-rooted teeth were selected and divided into three groups, each containing 28 teeth. The teeth were instrumented with rotary instruments sequentially: Group A: ProFile Rotary Instruments; Group B: FlexMaster Rotary Instruments; and Group C: RaCe Rotary Instruments. Instrumentation was performed by the crown-down method and according to the manufacturer's instructions. The specimens were then examined with SEM according to Hülsmann's classification. One-way ANOVA and a post hoc Tukey test were used for statistical analysis. The results showed that there were no statistically significant differences among the three groups in the coronal third (P = 0.39), but at the apical and middle thirds there were statistically significant differences between the RaCe group and the other groups (P < 0.05). Smear layer in the RaCe group was less than that in the ProFile and FlexMaster groups, but the difference between the ProFile group and FlexMaster group was not statistically significant (P > 0.05). It was concluded that RaCe Rotary Instruments produce less smear layer than FlexMaster and ProFile Rotary Instruments.

The Comparison of the Effect of Endodontic Irrigation on Cell Adherence to Root Canal Dentin

The purpose of this study was to compare the effect of 10 different endodontic irrigation and chelating treatments on dental pulp stem cell (DPSC) attachment to root canal surfaces. Thirty-eight extracted human nondiseased single-canal teeth were cleaned and shaped using ProTaper and ProFile rotary instrumentation (Tulsa Dentsply, Tulsa, OK). The irrigation treatments investigated were 6% sodium hypochlorite, 2% chlorhexidine gluconate, Aquatine Endodontic Cleanser, and Morinda citrifolia juice. The irrigation treatments were used in conjunction with EDTA or MTAD. The instrumented teeth were immediately placed in cell culture with confluent DPSCs for 1 week. The number of attached DPSCs appeared to be correlated with the cytotoxicity of the root canal irrigating solution (analysis of variance, p < 0.0001). The presence or absence of the smear layer had little influence on DPSC activity (chi-square, p > 0.05). The results suggest that biocompatible irrigants are needed to promote DPSC attachment to root canal dentin, which is essential to accomplish some regenerative endodontic therapies.

Efficacy of ProTaper Universal Retreatment Files in Removing Filling Materials during Root Canal Retreatment

The aim of this study was to evaluate the efficacy of the ProTaper Universal System rotary retreatment system and of Profile 0.06 and hand instruments (K-file) in the removal of root filling materials. Forty-two extracted single-rooted anterior teeth were selected. The root canals were enlarged with nickel-titanium (NiTi) rotary files, filled with gutta-percha and sealer, and randomly divided into 3 experimental groups. The filling materials were removed with solvent in conjunction with one of the following devices and techniques: the ProTaper Universal System for retreatment, ProFile 0.06, and hand instruments (K-file). The roots were longitudinally sectioned, and the image of the root surface was photographed. The images were captured in JPEG format; the areas of the remaining filling materials and the time required for removing the gutta-percha and sealer were calculated by using the nonparametric one-way Kruskal-Wallis test and Tukey-Kramer tests, respectively. The group that showed better results for removing filling materials was the ProTaper Universal System for retreatment files, whereas the group of ProFile rotary instruments yielded better root canal cleanliness than the hand instruments, even though there was no statistically significant difference. The ProTaper Universal System for retreatment and ProFile rotary instruments worked significantly faster than the K-file. The ProTaper Universal System for retreatment files left cleaner root canal walls than the K-file hand instruments and the ProFile Rotary instruments, although none of the devices used guaranteed complete removal of the filling materials. The rotary NiTi system proved to be faster than hand instruments in removing root filling materials.

Evaluation of Morinda citrifolia as an Endodontic Irrigant

The purpose of this study was to compare the in vitro effectiveness of M orinda citrifolia juice (MCJ) with sodium hypochlorite (NaOCl) and chlorhexidine gluconate (CHX) to remove the smear layer from the canal walls of endodontically instrumented teeth. Sixty extracted, single-rooted, mature, permanent, human premolar teeth with a single canal were inoculated with Enterococcus faecalis at 37°C in a CO 2 atmosphere for 30 days. The teeth were randomly allocated to 6 treatment groups; the pulp chamber was accessed, cleaned, and shaped by using ProTaper and ProFile rotary instrumentation to a size 35. During instrumentation the irrigation was provided by MCJ, NaOCl, CHX, MCJ/CHX, followed by a final flush of 17% ethylenediaminetetraacetic acid (EDTA). MCJ irrigation was also followed by a final flush of saline, and saline irrigation was also used as a negative control. The teeth were then processed for scanning electron microscopy, and the removal of smear layer was examined. Data were analyzed by χ 2 statistical tests ( P values) at a significance of 95%. The most effective removal of smear layer occurred with MCJ and NaOCl, both with a rinse of 17% EDTA. Both MCJ and NaOCl treatments were similarly effective with a rinse of 17% EDTA ( P < .2471) to completely remove up to 80% of the smear layer from some aspects of the root canal. MCJ was more effective than CHX for removing smear layer ( P < .0085) and saline as the negative control ( P < .0001). The efficacy of MJC was similar to NaOCl in conjunction with EDTA as an intracanal irrigant. MJC appears to be the first fruit juice to be identified as a possible alternative to the use of NaOCl as an intracanal irrigant.