Quantitative evaluation of apically extruded debris with Twisted File Adaptive instruments in straight root canals: reciprocation with different angles, adaptive motion and continuous rotation

The effect of different kinematics on apical debris extrusion with a single-file system

To compare the amount of extruded debris caused by different motions using a single-file system. Fifty mandibular first molar teeth were randomized into 5 groups (n = 10) according to the motion tested: Optimize Torque Reverse (OTR), TF Adaptive Motion (TFA), continuous rotation (CR), reciprocation motion (+ 150°, -30°) (REC), and Jeni motion (Jeni). One Curve single file 25/06 (Micro-Mega, Besançon, France) was used in all experimental groups. The root canals were irrigated with 2.5% NaOCl, and the extruded debris were collected at pre-weighted glass vials. The glass vials were kept inside an incubator for one week at 70 °C to dry out the irrigating solution. The extruded debris was quantified by subtracting the pre-instrumentation from the post-instrumentation weight of the glass vials. The time required for each instrumentation procedure was digitally recorded. All data were analyzed statistically with one way ANOVA and post hoc Tukey test (P < 0.05). All the motions extruded apically debris with Jeni mode caused significantly less debris extrusion than TFA, REC, and CR (P < 0.05) while no significant difference emerged with OTR. Preparation time was not significantly different in all groups. Within the limits of the present study, all the kinematics produced apically debris extrusion, with Jeni reporting a similar amount of debris compared with OTR and significantly less than TFA, REC, and CR. Preparation time was similar among the tested kinematics.

Apically extruded debris of different file systems used with various kinematic movements during retreatment: An in vitro study

This study aimed to examine the amount of apically extruded debris and time during retreatment with five current file systems, which exhibit various kinematic movements. One hundred upper central incisors were shaped with manual files and filled using the thermoplastic injection method. The root canal fillings in each group (n = 20) were removed using the Genius (GN), ProTaper Next (PTN), Reciproc (RCP) Blue, Tango-Endo (TE) and Twisted File Adaptive (TFA) file systems. The apically extruded debris was collected in preweighed Eppendorf tubes. Time to reach working length and total time were also recorded. The PTN, RCP Blue and TFA instruments caused significantly less apically extruded debris and shorter total retreatment time than the GN and TE file systems (p < 0.05). The time to reach the working length was the shortest in the PTN group compared to the other groups (p < 0.05). All file systems extruded debris while removing the root canal filling.

Evaluation of apical extrusion of debris and centering ability in different nickel-titanium files during curved root canal preparation

BACKGROUND

Curved root canals lead to difficulties in cleaning, shaping and filling the root canal system. Apical extrusion of debris and root canal transportation are important factors causing postoperative complications. In clinical practice, commonly selected instruments include multifile NiTi systems, such as M3-Pro PLUS (M3-PRO), Orodeka Plex 2.0 (ODP), Rotate (ROT), and Protaper Gold (PTG), as well as single-file NiTi systems, such as M3-L Platinum 2019 (M3L), Waveone Gold (WOG), and Reciproc Blue (RCB). This study aimed to comprehensively evaluate the differences in the apical extrusion of debris and centering ability of the above NiTi files.

METHODS

Seventy 3D-printed resin teeth were used (n = 10). The apically extruded debris was collected in a preweighed centrifuge tube. The resin teeth with or without root canal preparation were cut into separate cross sections at 1 mm, 3 mm, 5 mm, and 7 mm away from the root apex, and then the root canal transportation and centering ratio of each cross section were calculated.

RESULTS

Apical extrusion of debris was highest in RCB but lowest in OD-P (P < 0.05). Root call deviation was lowest in ROT at the 3 mm level, in PTG at the 5 mm level, and in PTG and ROT at the 7 mm level (P < 0.05). The centering ratio of NiTi files was highest in the RCB group at the 3 mm level, in the PTG group at the 5 mm level, in the ROT group at the 7 mm level (P < 0.05).

CONCLUSIONS

For NiTi files with the same system, the cross-sectional design is the greatest factor affecting the extrusion of debris, and motion mode is the second. In addition, the multifile system could reduce the degree of root canal transportation.

Evaluation of Apically Extruded Debris During Retreatment Procedures Using Various File Systems in Teeth With Simulated Apical Root Resorption: An In Vitro Study

Aim The aim of this study was to compare the amount of debris produced apically during the removal of root canal obturating material by using various files in extracted teeth with simulated apical root resorption. Materials and methods An in vitro study was conducted in the root canals of 90 extracted mandibular premolar teeth that were prepared with a ProTaper Gold rotary file (Dentsply Maillefer, Ballaigues, Switzerland) and filled with gutta-percha and an AH Plus sealer (Dentsply Maillefer, Ballaigues, Switzerland) using a cold lateral compaction technique. A total of 45 mandibular premolar teeth were randomly assigned to three control groups (i.e., the ProTaper Universal retreatment file (Dentsply Maillefer), the Reciproc Blue file (VDW, Munich, Germany), and the HyFlex Remover file (Coltene/Whaledent, Altstatten, Switzerland) for the removal of root canal filling material, whereas the remaining 45 teeth were treated as the experimental group and their apical portion was modified to simulate apical root resorption. The teeth of this experimental group were randomly divided into three subgroups according to the same three techniques used with the control groups for the removal of root canal filling materials. The apically extruded debris was collected into pre-weighed borosilicate glass tubes and then dried. The mean weight of the apically extruded debris was assessed using an analytical balance to an accuracy of 10^-4 g. Further, the data were analyzed using the Kruskal-Wallis test and Tukey's post hoc test. Results In the simulated apical root resorption groups, all file systems were associated with significantly more debris extrusion than the groups without simulated root resorption (a < 0.05). In both the control groups and experimental groups, the ProTaper Universal retreatment file was associated with the least weight of the apically extruded debris (a < 0.05), followed by the Reciproc Blue file and the HyFlex Remover file. Conclusion The amount of debris extruded apically was significantly greater in the teeth with simulated apical root resorption than in those without it. Further, during the removal of the root canal filling materials, HyFlex Remover was associated with significantly more apically extruded debris in all groups.

Effect of mode of rotation on apical extrusion of debris with four different single-file endodontic instrumentation systems: Systematic review and meta-analysis

This systematic review and meta-analysis evaluated whether single-file endodontic instrumentation systems with the reciprocating type of motion are responsible for more debris extrusion than single-file endodontic instrumentation systems with the full rotational type of motion. Electronic and manual searches were performed following the recommendations of Preferred Reporting Items for Systematic Reviews and Meta-Analysis - PRISMA. We included studies comparing rotary (Neoniti and/ OneShape) versus reciprocating (WaveOne and/ Reciproc) systems. We evaluated the quality of studies and performed statistical analysis using R-Project software. Eight studies of high quality were included to perform the meta-analysis. Subgroup analysis was also done. The overall risk of bias was too low. In conclusion, single-file reciprocating systems tend to generate more extrusion of debris than single-file rotary systems.

Influence of pecking frequency at working length on the volume of apically extruded debris: A micro-computed tomography analysis

Background/purpose

There is no consensus to date on how many repetitive pecking motions at working length (WL) should be regarded as optimal during instrumentation. Therefore, this study aimed to evaluate the effect of pecking frequency at WL on the volume of apically extruded debris using three single-file systems in curved, oval-shaped canals.

Materials and methods

Forty-five single-rooted mandibular premolars with curved, oval-shaped canals were prescanned by micro-computed tomography, anatomically paired-matched, and randomly divided among three groups (n = 15 each): Reciproc Blue (RB), WaveOne Gold (WOG) and XP-endo Shaper (XPS). Samples were embedded in agarose gel to collect extruded debris. After preparation to the WL, each sample was rescanned after one, two, four, 10, and 20 pecking motions at WL, respectively. The debris volume was innovatively calculated by a modification of an existing method using micro-computed tomography. The apical preparation size was also measured. Data were compared using a two-way repeated-measures analysis of variance.

Results

All single-file systems extruded debris apically, irrespective of the pecking frequency at WL. The extruded debris volume correlated positively with the minor foramen size (P < 0.05); both increased with pecking frequency for each single-file system (P < 0.05). The minor foramen size corresponded to the instrument tip size when reaching the WL once.

Conclusion

To produce less debris extrusion and obtain a predictable foramen size corresponding to the instrument tip size, a single pecking motion may be preferred when using single-file systems. Caution should be exercised when applying the current results to clinical situations.

Retreatment of Experimental Carrier-Based Obturators with the Remover NiTi Instrument: Evaluation of Apical Extrusion and Effects of New Kinematics

The objective of this study is to evaluate the retreatment time and weight of apically extruded debris yielded by two different kinematics during the removal of different root canal filling materials. Forty straight single-rooted extracted teeth were instrumented with HyFlex CM files and obturated with two different techniques: 25.04 HyFlex experimental carrier-based obturators (Coltène/Whaledent, Altstätten, Switzerland) (group 1) or 25.04 single gutta-percha cones (Roeko Coltène/Whaledent, Altstätten, Switzerland) (group 2) and Guttaflow Bioseal as the sealer. Samples were divided into four subgroups (n = 10) according to the used kinematics for the removal of root canal filling materials: continuous rotation (A) or retreatment motion (B) with a Remover and HyFlex EDM Nickel-Titanium instruments activated with a CanalPro Jeni micromotor (Coltène/Whaledent, Altstätten, Switzerland). Time for retreatment was digitally recorded, and debris extruded from the apex was collected in Eppendorf tubes and weighted with an analytical balance. Data on retreatment time and apical extrusion were statistically analyzed with the Kruskal–Wallis test (p < 0.05). Working length was achieved in all the retreated samples. The removal of root filling material resulted significantly faster with the Jeni mode (p < 0.001), and the difference was significant for the removal of both filling materials (p < 0.05). No significant differences on debris extrusion between single cone and experimental obturators groups were noted (p > 0.05), and no significant differences between kinematics (continuous rotation vs. Jeni motion) were observed (p > 0.05). All the tested retreatment strategies lead to an extrusion of material from the apex, and the weight of apically extruded debris was similar. The use of the innovative CanalPro Jeni kinematics accelerates the time for the removal of root filling materials.

The effect of two rotary and two reciprocating NiTi systems on postoperative pain after root canal retreatment on single-rooted incisor teeth: A randomized controlled trial

AIM

This randomized clinical trial aimed to assess the effect of two rotary (ProTaper Retreatment + ProTaper Gold and Hyflex EDM) and two reciprocating (Reciproc Blue and WaveOne Gold) NiTi systems on postoperative pain after root canal retreatment on single-rooted incisor teeth.

METHODOLOGY

One hundred and eighty patients scheduled for root canal retreatment were randomly assigned to one of the four groups according to the NiTi system (ProTaper Retreatment + ProTaper Gold, Hyflex EDM, Reciproc Blue or WaveOne Gold) used for the removal of root canal fillings and further canal preparation. The working length was determined to be 1 mm shorter than the '0.0' mark of the apex locator. Root canals were filled with gutta-percha and an epoxy resin-based root canal sealer using a lateral compaction technique. The teeth were restored using a resin composite material. A single operator performed the retreatments in a single visit. The incidence and intensity of postoperative pain were rated on a numeric rating scale by patients 24, 48 and 72 h after retreatment. The number of analgesic tablets (400 mg Ibuprofen) taken by patients was also recorded. Data were analysed using the Mann-Whitney U, Wilcoxon and chi-square tests.

RESULTS

For the intensity of postoperative pain, the difference between the four groups was not significantly different (p > .05). No significant difference was found between the groups in terms of analgesic medication intake (p > .05).

CONCLUSIONS

The rotary and reciprocating NiTi systems tested in this study were associated with similar intensity of postoperative pain and intake of analgesics following root canal retreatment on single-rooted incisor teeth completed in one visit.

Evaluation of type of kinematics on glide path procedures and torsional fatigue resistance after preparation of moderately curved canals

Sixty moderately curved canals of mandibular molars classified as Vertucci's type IV canal configuration were selected by micro-CT 1174. The teeth were divided into two groups according to the kinematics used, whether reciprocating or rotary motion (n=30, totaling 60 mesial root canals). The instruments used to perform the glide path procedures had identical features (0.15 mm of tip size, 0.04 mm/mm taper, thermal treatment, and square cross-section), but differed in the direction of the cutting blade. The duration of the procedure and the absolute and percentage frequency of the instruments to reach the full working length were recorded. The torsional test (3630-1; 1992) was performed on both used and unused instruments, to evaluate a possible reduction in the torsional resistance when using the glide path procedure. Statistical analysis was performed using the unpaired t-test and the chi-square test, and the level of significance was set at 5%. The type of kinematics used affected the duration of glide path procedures, and the reciprocating motion seemed to induce less torsional stress during glide path procedures.

Comparison of apical debris extrusion using clockwise and counter-clockwise single-file reciprocation of rotary and reciprocating systems

The aim was to evaluate apical debris extrusion produced by a single-file system used in counter-clockwise reciprocation and compare it to rotary single-file systems used in clockwise rotation and clockwise reciprocation. A total of 100 first mandibular molars were divided into five groups (n = 20): (i) WaveOne Gold Glider and Primary instrument in counter-clockwise reciprocation; (ii) One G and One Curve file in clockwise rotation; (iii) One G and One Curve file in clockwise reciprocation; (iv) TruNatomy Glider and Prime instrument in clockwise rotation; and (v) TruNatomy Glider and Prime instrument in clockwise reciprocation. Apical debris extruded was measured after glide path preparation and canal preparation. WaveOne Gold displayed significantly higher amounts of apical debris extrusion in all the groups (P < 0.05). The lowest mean values were recorded by clockwise reciprocation groups: TruNatomy Glider, One Curve and TruNatomy Glider and Prime combined value, for glide path, canal preparation and combined mean values, respectively.

Apically Extruded Debris following Programmed Over Instrumentation of Curved Canals with Three Nickel Titanium Rotary Instruments

OBJECTIVES

 This in vitro study aimed to compare the amount of mixed and dried debris extruded with three endodontic NiTi (nickel-titanium) systems at three levels beyond the major apical foramen. The null hypothesis is that there would be no differences between the different rotary systems in terms of apically extruded debris.

MATERIALS AND METHODS

 Forty-eight roots of human extracted molars with 20 to 40-degrees curvature were divided randomly into three groups (n = 16) instrumented with ProTaper Next, BT RaCe, and WaveOne Gold, respectively. Instrumentation was performed at the major foramen and over instrumented 0.5 mm, 1.0 mm and 1.5 mm beyond. Irrigation was performed with sodium hypochlorite. Apically extruded debris was collected.

RESULTS

 Comparison of mixed extruded debris (solution/debris)and dried debris according to group and level of instrumentation showed that WaveOne Gold at the foramen and ProTaper Next beyond the foramen (p < 0.0001) resulted in significantly less extruded debris than other files and within the four levels using repeated measures analysis of variance (p < 0.0001b).

CONCLUSIONS

 All systems exhibit extruded debris during instrumentation but in different amounts.

Apically extruded debris produced during glide path preparation using R-Pilot, WaveOne Gold Glider and ProGlider in curved root canals

The present study aimed to compare the apically extruded debris produced during glide path preparation using R-Pilot (RP), WaveOne Gold Glider (WGG) and ProGlider (PG) with the subsequent preparation using Reciproc Blue in curved root canals. Mesial roots of mandibular molars with angle of curvature between 25° and 35° were selected (n = 20). The Myers and Montgomery method was used to collect and assess apically extruded debris. The glide path was prepared either manually with K-file, ProGlider, R-Pilot or WaveOne Gold Glider. Manual preparation group produced the highest amount of apically extruded debris (P < 0.05), while all groups caused debris extrusion. There were no significant differences among the extruded debris caused by RP, PG and WGG groups (P > 0.05). Apically extruded debris produced by engine-driven reciprocational or continuous rotational single file glide path instruments was similar, whereas manual glide path preparation was associated with the greatest amount of extruded debris.

Evaluation of apically extruded debris during the removal of canal filling material using three different Ni-Ti systems and hand files in teeth with simulated apical root resorption

AIM

To compare the weight of apically extruded debris produced during the removal of root canal filling material using various files in extracted teeth with simulated apical root resorption.

METHODOLOGY

The root canals of one hundred and twenty extracted mandibular premolar teeth were prepared with Revo-S files and filled using a cold lateral compaction technique with gutta-percha and a resin-based sealer (AdSeal; Meta-Biomed, Cheongwon, Korea). Sixty teeth were randomly assigned to four control groups (hand file, ProTaper Universal retreatment file, D-RaCe retreatment file, and Reciproc file) for the removal of root canal filling material. The apical portion of the remaining 60 teeth was modified to simulate apical root resoption, and the teeth were then randomly divided into 4 experimental groups (using the same techniques as in the control groups) for the removal of root canal filling material. Apically extruded debris was collected into pre-weighed Eppendorf tubes and then dried. The mean weight of the apically extruded debris was assessed with an analytical balance to an accuracy of 10^-4  g. Data were analysed using two-way analysis of variance and a Tukey's post hoc test.

RESULTS

In the simulated apical root resorption groups, all file systems were associated with significantly more debris extrusion compared to the groups without simulated resorption (P < 0.05). The amount of apically extruded debris was greatest in the hand file groups compared with the other groups (P < 0.05). In the groups with simulated apical root resorption, the Reciproc system was associated with the least weight of apically extruded debris (P < 0.05), whereas there was no significant difference between the ProTaper Universal retreatment and D-RaCe files (P > 0.05). In the groups without simulated apical root resorption, there was no significant difference between Reciproc, ProTaper Universal retreatment and D-RaCe retreatment files (P> 0.05). The time required to remove the root canal filling material was as follows: hand file > ProTaper Universal retreatment = D-RaCe retreatment > Reciproc (P < 0.05).

CONCLUSIONS

The weight of apically extruded debris was significantly greater in teeth with simulated apical root resorption than in those teeth without simulated apical root resorption. Hand files were associated with significantly more apically extruded debris in all groups during removal of root canal filling material.

Evaluation of Apically Extruded Debris Using Continuous Rotation, Reciprocation, or Adaptive Motion

The aim of this study was to compare the amount of apically extruded debris during root canal instrumentation using ProTaper Next (PTN), Twisted File (TF) Adaptive, and Reciproc instruments. Forty-five extracted human maxillary canines were selected and randomly assigned into 3 groups. The root canals were prepared using PTN instruments with continuous rotation (n=15), TF Adaptive instruments with adaptive motion (n=15), Reciproc instruments with reciprocating motion (n=15). During the preparations, canals were irrigated using distilled water and material extruded apically was collected in pre-weighed Eppendorf tubes. After a 5-day drying period in an incubator, the tubes were weighed and the dry weight of the extruded debris was calculated. Data distributions were assessed via the Shapiro-Wilk test, and groups were compared via the Kruskal-Wallis test. The greatest amount of debris extruded by TF Adaptive and the least by PTN, but the difference was insignificant between groups (p=0.259). All instrumentation systems were associated with debris extrusion.

Nickel-titanium instruments in endodontics: a concise review of the state of the art

The introduction of automated instrumentation in endodontics represented a major advance in progress for this specialty, with improvements in the quality and predictability of root canal preparation and a significant reduction in procedural errors. In recent years, endodontic instruments have undergone a series of changes brought about by modifications in design, surface treatments, and thermal treatments. In addition, new movements have also been incorporated to offer greater safety and efficiency, optimizing the properties of the NiTi alloy, especially through eccentric rotary motion. An understanding of the mechanical properties of these new NiTi instruments and their effect on the clinical performance of root canal preparation is essential if dental practitioners are to select the instruments that provide optimal clinical outcomes, especially in curved or flattened canals. The objective of this literature review is to present and discuss the characteristics of the NiTi alloys used in the major instrumentation systems available in the market, as well as the influence of the metallurgical and mechanical properties of NiTi instruments and the movements that drive them, to enable more accurate and predictable planning of root canal preparation.

Apical extrusion of debris during root canal preparation using a novel nickel-titanium file system: WaveOne gold

Aim:

This study was intended to evaluate the amount of apically extruded debris following root canal preparation with three different instrumentation systems.

Materials and Methods:

Sixty mandibular incisor teeth were selected and randomly divided into three groups (n = 20/group) according to the instrumentation system used: the ProTaper Next (PTN; Dentsply Maillefer, Ballaigues, Switzerland), the Twisted File Adaptive (TFA; SybronEndo, Orange, CA, USA), and the WaveOne Gold (WOG; Dentsply Maillefer, Ballaigues, Switzerland). All apically extruded debris was collected and dried in preweighed glass vials. The mean weight of the apically extruded debris was obtained using a microbalance. The time for root canal preparation was also recorded. The data were analyzed using a one-way analysis of variance.

Results:

The mean weights of apically extruded debris were 0.00035 ± 0.00014 g (PTN); 0.00023 ± 0.0001 g (TFA); and 0.00019 ± 0.0001 g (WOG) (P < 0.01). The mean preparation time value was 301,13 ± 62.14 s (PTN); 234.27 ± 34.88 s (TFA); and 239.8 ± 58.6 s (WOG) (P < 0.05).

Conclusions:

The PTN system extruded more debris than the TFA and WOG systems. The TFA and WOG systems were faster than the PTN system.

Influence of three Ni-Ti cleaning and shaping files on postinstrumentation endodontic pain: A triple-blinded, randomized, controlled trial

Aim:

This randomized, controlled trial evaluated the incidence of postinstrumentation pain on using two different rotary Ni–Ti and one reciprocating Ni–Ti cleaning and shaping systems.

Materials and Methods:

Asfter sample size estimation, a total of 152 patients were randomized to three groups (Group WO [WaveOne], Group PU [ProTaper Universal], and Group Mt [Mtwo]). Selection of patients was based on root curvature, periapical lesion, vitality, gender, and diagnosis of the patient. A similar clinical protocol was followed and endodontic treatment was performed. Pre- and post-instrumentation pain scores (2, 4, 6, 8, 12, 36, and 48 h) were recorded using visual analog scale score. Kruskal–Wallis test was done for overall comparison of the groups. Bonferroni-corrected Mann–Whitney test was done for pair-wise comparisons and Friedman test was done to compare pain between time points in each file system (P < 0.05).

Results:

All preinstrumentation pain values were higher than postinstrumentation pain values (P < 0.05). At 48 h, patients in Group WO experienced more pain compared to the other two groups. Pain scores of nonvital teeth were significantly higher when compared to vital teeth. Among nonvital teeth, patients in Group WO had early onset of pain at 6 h and lasted till 48 h, whereas pain started at 12 h and lasted till 36 and 48 h for Group Mt and Group PU, respectively.

Conclusion:

Patients treated with WaveOne files experienced more pain when compared to the other files. Nonvital teeth experienced more pain compared to vital teeth. Group Mt had the lowest postinstrumentation pain.