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Comparing the root canal filling removal efficiency of XP-endo retreatment system with hand Files, R-endo, reciproc and protaper universal retreatment systems in curved root canals: a micro-CT study

BMC Oral Health volume 25, Article number: 544 (2025) Cite this article

Abstract

Background

Residual root canal filling material might inhibit the efficacy of irrigation materials, medicaments and sealers during the endodontic non-surgical retreatment. The aim of this study was to compare the efficacy of the XP Endo Retreatment file with other retreatment systems on removing the root canal filling materials by using Micro-CT during the endodontic retreatment.

Methods

Sixty human mandibular molars with mesial root curvature between 20° and 40° were included in the study. Mesiobuccal canals of specimens were prepared with the ProTaper Next file and filled with gutta percha and AH Plus sealer. Samples were scanned with Micro-CT and they were randomly divided into 5 experimental groups. Root canal treatments were removed with the following systems.

Group PTUR: Root canal filling was removed using ProTaper Universal Retreatment System.

Group Rec25: Reciproc R25 file was used to remove the root canal filling.

Group RE: Retreatment of specimens were performed using R-Endo Retreatment System.

Group XPER: Root canal filling was removed using XP Endo Retreatment System.

Group HF: Hand files and Gates Glidden burs was used to remove the root canal filling.

The time (second) from the use of the first file to reach the WL (T1) and the time (second) to remove all obturation material (T2) were recorded. Micro-CT images were obtained from the samples after removing the root canal filling and the volume of the residual root canal filling was calculated. The data was statistically analyzed (P < 0.05).

Results

The residual root canal filling volume and the percentage of residual root canal filling material (%) in the RE and Rec25 groups were statistically higher than the PTUR, XPER, and HF groups. T1 and T2 values were the highest in the HF and time values were the lowest in the XPER.

Conclusions

According to the results of this study, all tested methods could not completely remove filling material from the root canal. PTUR, XPER, and HF removed the root canal filling more efficiently than Rec25, and RE. It was concluded that the XP-Endo group was the fastest retreatment system among the tested groups.

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Background

Improper chemo-mechanical shaping or obturation of root canal (RC), insufficient disinfection, and weak coronal restoration could lead to endodontic treatment failures [1, 2]. The most common treatment option for teeth with failed RC treatment is non-surgical endodontic retreatment [3]. The main purpose of non-surgical endodontic retreatment is to remove the obturation material and eliminate the microorganisms causing the periapical pathology [4, 5]. The residual obturation material in RCs during endodontic non-surgical retreatment process might prevent the efficiency of irrigation solutions and medicaments on residual microorganisms and periradicular infection might not be healed [4, 6].

Several instruments and techniques such as hand instruments, rotary or reciprocating systems, sonic and ultrasonic irrigation systems have been suggested to remove the endodontic obturation materials [4, 6, 7]. Engine driven Nickel-titanium (NiTi) file systems are more effective than hand files by reducing the treatment time and operator fatigue [5]. However, many studies showed that none of these retreatment systems were capable of totally removing the RC filling remnants [1, 2, 4, 6, 8].

The ProTaperUniversal Retreatment file-system (Dentsply Maillefer, Ballaigues, Switzerland), was manufactured for the removal of the RC filling materials. The system has three files; D1 (tip size 0.30), D2 (tip size 0.25) and D3 (tip size 0.20). The D1 file has a length of 16 mm and a taper of the file is 0.09 and used for initial preparation in the coronal region of the RC. The D2 instrument is suggested at the middle third and it has a length of 18 mm with a 0.08 taper. The D3 file has a length of 22 mm with a 0.07 taper [9]. The files have convex triangular cross-section design [10].

Reciproc (VDW, Munich, Germany) is an engine driven single-file NiTİ system used with reciprocating mode of endodontic motors is mainly manufactured for RC preparation and suggested for removal of the RC obturation. The file has an S-shaped cross-sectional design and it is manufactured with three instrument sizes (25/0.08, 40/0.06, and 50/0.05) [6].

The R-endo retreatment file system (Micro-Mega, Besancon-France) is manufactured particularly to remove the RC obturation material. The R-endo system has three files R1, R2 and R3 with a length of 15 mm (0.08 taper), 19 mm (0.06 taper), and 23 mm (0.04 taper), respectively. The R1 file is used in the coronal part, R2 is used in the middle part, and R3 is used in the apical region of the RC. The file has an inactive tip of size #25 and a triangular cross-sectional design. Also, it has three equally spaced cutting edge with no radial land [11, 12].

The XP-Endo retreatment file system (FKG Dentaire, La Chaux-de Fonds, Switzerland) contains an XP-endo Shaper and XP-endo Finisher R (XPFR) instruments. The XP-endo shaper files have a length of 25 mm and the tip size and taper are ISO 30/0.04. The XPFR is dedicated for removing the RC filling remnants. The file is manufactured with Max-Wire alloy with zero taper and it shows phase transformation (to austenitic phase) at body temperature that causes the “spoon like” shape at the tip of the instrument [8, 13]. Manufacturer claims that the “spoon like” shape of the file provides to reach to the irregularities of RC system without altering the original RC shape. The files of XP-endo retreatment system have a triangular-shaped cross-section design [14].

Micro Computed Tomography (micro-CT) is an imaging method that provides to evaluate the specimens in three dimensions quantitatively and qualitatively with high resolution [15]. Micro-CT allows the volumetric analysis and reconstruction of specimens, evaluation of the alterations in the instrumented surfaces of the RC system, conicity, and transversal-sectional shape of the teeth [16, 17]. Micro-CT is advantageous to assess the anatomy of the RC, changes in the RC space after the preparation, and also the quality of RC fillings and the quantity of remaining obturation materials after endodontic non-surgical re-treatment procedures [16].

Although there are several systems to use during endodontic retreatment none of them able to remove the obturation material completely. According to our knowledge there is no study comparing the XP-Endo retreatment file system with other four retreatment systems by using the micro-CT. The objective of this in-vitro study was to compare the performance of different engine driven retreatment file systems with XP-Endo retreatment file on removal of the RC obturation during the retreatment of curved mesial RCs of the lower molars by using Micro-CT. Also the retreatment time of file systems and hand files was compared. The null hypotheses of the study were that there were no differences between the operating times and efficiency on removing the RC fillings of tested file systems.

Methods

G*Power 3.1.9.7 Program was chosen to calculate the sample size with α type error of 0.05, β type error of 0.95 and the effect size (f) 0.6769 by using the data of a previous study [1]. After getting the approval of the study design by the Ethical Committee of the University (10.12.2019/36), Eighty-seven human lower molars extracted for periodontal reasons were saved and left in saline solution for a maximum period of six months. Mandibular molars with curved mesial root and mature apex and without previous RC treatment were selected for this study. Radiographic image was obtained to assess the curvature of the RCs in the mesial root for each sample. RCs with a curvature between 20° and 40° were chosen for the study. Curvature of the teeth were determined by using the method of Schneider [18]. The coronal portion of the remaining 60 teeth were abraded under water cooling using a high-speed fissure bur to obtain 18 ± 1 mm tooth length and the access cavities were prepared. A #10 K file (VDW GmbH, Munich, Germany) was placed into the curved mesial RC until the tip of the file was seen at the apex of the root, and 1 mm from this length was subtracted to calculate the working length (WL). The RCs were prepared by using the #15 K-file (VDW GmbH, Munich, Germany) and later ProTaper Next X1 and X2 NiTi files (Dentsply Sirona, Ballaigues, Switzerland). The ProTaper Next program of the X-Smart Plus endodontic motor (Dentsply Maillefer, Ballaigues, Switzerland) was used (300 rpm and 2 Ncm torque). During the RC preparation, the RCs were irrigated with 5% sodium hypochlorite (NaOCl) (Werax, Izmir, Turkey) solution. A 27-gauge needle placed almost 2 mm short of the WL was used for the irrigation procedure. The RCs were irrigated with 17% ethylenediaminetetraacetic acid (EDTA) (Werax, Izmir, Turkey), 5% NaOCl and distilled water for 1 min after finishing the mechanical preparation. Afterwards, the RCs were dried with paper-points and obturated with AH Plus sealer (Dentsply Sirona, Maillefer, Konstanz, Germany) and ProTaper Next X2 gutta percha (Dentsply Sirona, Maillefer, Ballaigues, Switzerland) using the single-cone technique. Access cavities were sealed with temporary filling material (Cavit-G, 3 M Espe, Seefeld, Germany) after removing the coronal excessive gutta percha with a heated plugger at the RC orifice level. Later, roots were radiographed in mesio-distal and bucco-lingual directions to verify the quality of the RC filling. Specimens were left at 37 °C and in 100% humidity for 2 weeks to completely set [1].

Pre-retreatment micro-CT scanning

The mandibular molars were randomly divided into 5 equal experimental groups of 12 specimens each by using a computer based simple randomization program (www.random.org). All specimens were imaged using the micro-CT device (Bruker-Skyscan 1272, Billerica, Massachusetts, USA) (Fig. 1-A). The X-ray source was calibrated at 100 μA and 100 kV using an aluminum and a copper filter. The micro-CT images were obtained with every 0.8° of a 180° rotation and each specimen was scanned for almost 50 min.

Fig. 1
figure 1

A-B Rrepresentative three-dimensional micro-CT images of each group; A pre-retreatment, B post-retreatment images

Full size image

Retreatment procedures

Group PTUR: Removal of the RC obturation of specimens were performed by using the ProTaper Universal-Retreatment files (Dentsply Maillefer, Ballaigues, Switzerland) at 2.5Ncm torque and 300 rpm speed of the X-Smart device. The D1 (30/0.09) file was operated for the removal of the coronal obturation, D2 (25/0.08) file was operated to remove the filling material in the middle part and D3 (20/0.07) file was used for removal of the apical root filling at the WL. RC irrigation was performed with 5% NaOCl after the use of each file.

Group Rec25: RC filling of the specimens was removed by using the Reciproc 25 file (VDW, Munich, Germany) at “Reciproc all” program (at 300 rpm and 150°−30°) of the X-Smart Plus device with in and out pecking motion. The R25 (25/0.08) file was operated with light apical pressure and brushing motion until it reached the WL. The instrument was removed from the RC after three pecking motions and the flutes of the file were cleaned. RC irrigation was performed with 5% NaOCl solution after removing the file from the RC.

Group RE: The RC obturation was removed using R-Endo system (Micro-Mega, Besancon, France) with the X-Smart Plus (2 Ncm torque and 350 rpm speed). The R1 (25/0.08) file was used for the removal of the coronal obturation, the R2 (25/0.06) was used to remove the obturation material in the middle part, and R3 (25/0.04) was used at the WL to remove the apical part of the RC filling. Irrigation was performed with 5% NaOCl after the use of each file.

Group 4 XPER: The retreatment procedure was performed using the XP-Endo retreatment system (FKG Dentaire, La Chaux-de Fonds, Switzerland). DR1 file (30/0.10) (FKG Dentaire, La Chaux-de Fonds, Switzerland) was used at 800 rpm speed and 1.5 Ncm torque to remove the coronal 3–4 mm of the RC obturation. The removal of the endodontic filling material was performed with an XP-Endo Shaper (30/0.04) file used at 1000 rpm speed and 1 Ncm torque operated in the X-Smart Plus endodontic device with a rotational movement. The file was used with an in-and-out movement until it reached the WL. The file was removed in each of the three cycles and the RCs were irrigated by using 5% NaOCl. After removing the RC obturation, the XP-Endo Finisher R (30/0.00) file was used to remove the RC filling remnants at WL. The file was used with a rotational movement at 800 rpm speed and 1 Ncm torque. The retreatment procedure of the XP-Endo retreatment system was performed in a 37 °C water bath to obtain phase transformation.

Group 5 HF: The coronal obturation was removed with Gates Glidden drills (Mani, INC, Tochigi, Japan) 3 and 2 respectively used at 2000 rpm. Subsequently, the RC fillings were removed with Hedstrom files (VDW GmbH, Munich, Germany) sized #30, 25, 20, and 15 using circumferential, quarter-turn push and pull movement until the #15 H file reached the WL. Then, #20, 25, and 30 H files were used at the WL by using circumferential, push and pull movement. Irrigation was performed with 5% NaOCl solution after changing each file.

All retreatment systems were used according to the manufacturers’ recommendations. 10 mL of 5% NaOCl solution was used for each sample during RC filling removal. Retreatment procedures of experimental groups were performed until the gutta percha and sealer remnants were not visible in the irrigation solution or the file flutes. Files were discarded after using in three RCs or a deformation on the file surface was seen. Two specimens were discarded from the study owing to the file fracture (PTU and HF groups). The time (as second) from the use of the first file to reaching the WL (T1) and the time (as second) to remove all obturation material (T2) were recorded during the experiment. Times for irrigation and file change were not included in the records.

The final RC preparation of each specimen was done by using the ProTaper Next X3 (tip size 0.30, taper 0.07) file used with the X-Smart Plus device at the ProTaper Next program (300 rpm speed, 2 Ncm torque). Final irrigation was performed with 5 mL of 17% EDTA, 5% NaOCl solutions and distilled-water after finishing the mechanical preparation. Subsequently, the RCs were dried with paper-points and access cavities were sealed with temporary filling material. Preparation of specimens for the study was performed by a single clinician experienced in endodontics.

Post-Retreatment Micro-CT scanning

Specimens were scanned using the micro-CT device (Bruker Skyscan 1272, Billerica, Massachusetts, USA) by using the same parameters of the first scanning (Fig. 1-B). The obtained images were transferred to the NRecon (ver. 1.6.10.4, SkyScan, Kontich, Belgium) and CTAn or DataViewer (ver. 1.17.7.2, SkyScan) softwares to visualize and evaluate the RC fillings quantitatively. Three and two dimensional images were reconstructed by a single micro-CT experienced researcher. The amount (mm3) of the filling material in the pre- and post-treatment images were calculated and the volume of the remaining obturation material was computed as a percentage. All measurements were performed twice by a single blinded researcher.

Statistical analysis

The obtained data was statistically analyzed with R studio statistical software program (R Core Team, Vienna, Austria) at a 5% significance level and a 95% confidence interval.

The volumes of residual RC obturation material values were distributed normally and analyzed with the One-way ANOVA test, and inter-group comparisons were done with the Tukey HSD test (P < 0.05).

The percentage values of residual obturation material were not distributed normally and were statistically analyzed with the Kruskal Wallis test (P < 0.05). The Bonferroni Dunn multiple comparison test was used to define the differences among the percentage of experimental groups (P < 0.05).

Retreatment times of experimental groups did not show normal distribution and were statistically analyzed with the Kruskal Wallis test (P < 0.05). The Bonferroni Dunn multiple comparison test was performed to specify the differences among the operation times of different retreatment systems (P < 0.05).

Results

The remaining obturation material was found in all experimental groups. A statistically significant difference between the volume of residual RC obturation material was observed between the PTUR, Rec25, RE, XPER, and HF groups (P < 0.05). The remaining obturation material values of Rec25 and RE groups were statistically higher than the PTUR, XPER and HF groups (P < 0.05). Also, the residual obturation material in the HF group was statistically higher than the PTUR and XPER groups (P < 0.05). Also, there was no statistically significant difference between the volume of the remaining material in the PTUR and XPER groups. The Rec25 and RE groups exhibited no statistical difference (P > 0.05) (Table 1).

Table 1 Minimum, maximum, mean ± standard error, standard deviation and median values of residual root canal filling material volume of experimental groups
Full size table

A statistically significant difference was found between the percentage values of the remaining obturation material between the PTUR, Rec25, RE, XPER, and HF groups (P < 0.05). The mean percentage values of residual RC obturation material in the RE and Rec25 groups were statistically higher than the PTUR, XPER and HF groups (P < 0.05). The RE and Rec25 groups exhibited no statistical difference. Also, no statistical difference was found between the mean percentage values of remaining obturation material in the PTUR, XPER and HF groups (P > 0.05) (Table 2).

Table 2 Minimum, maximum, mean ± standard error, standard deviation and median values of residual root canal filling material percent (%) of experimental groups
Full size table

Mean times to reach WL (T1) (Table 3) and to remove all obturation material (T2) (Table 4) of the experimental groups were statistically different (P < 0.05). T1 and T2 times in the HF were longer than in the other experimental groups (P < 0.05). Mean times to reach WL and to remove all obturation in the XPER group were statistically shorter than the other groups. Mean T1 and T2 time values in the PTUR and Rec25 groups were statistically shorter than in the RE group (P < 0.05). T1 and T2 times of the PTUR group were significantly longer than the Rec25 group (P < 0.05).

Table 3 Minimum, maximum, mean ± standard error, standard deviation and median values of time to reach apex (seconds)
Full size table
Table 4 Minimum, maximum, mean ± standard error, standard deviation and median values of time to remove root canal filling material (seconds)
Full size table

Discussion

The complete removal of RC filling materials and elimination of microorganisms and their toxins are crucial for the success of non-surgical endodontic retreatment. Remaining RC obturation materials obstruct the antimicrobial agents from reaching persistent microorganisms located in the RC irregularities and dentinal tubules [19]. Previous studies showed that there is no technique or file system can completely remove the obturation material during the retreatment procedures [2, 4, 6, 7, 13]. In this present study, we aimed to compare the retreatment efficiency of the XPER file system with hand files, Rec25, PTUR, and RE retreatment systems by using micro-CT. The percentage of remaining filling material was lower in the PTUR, XPER and HF groups. There was no statistical difference between the Rec25 and RE groups. Also, the PTUR, XPER and HF groups showed no difference when the amount of the residual obturation material percentage was compared. R25 which is one file system and RE system which has smaller taper than other systems represented more remaining obturation material. The lower percentage values of residual obturation material in the PTUR, XPER and HF groups could be related to the differences in the file kinematics, cross-sectional design differences, number of files in the system, cutting efficiency of the files, tip sizes or tapers of the file systems. The access files of PTUR and XPER systems which showed better removal performance than RE and R25 have greater taper and size than the other systems. Therefore, the null hypothesis of retreatment efficacy comparisons was partially rejected and the null hypothesis of time comparisons was completely rejected.

Rödig et al. [15] compared the retreatment efficiency of the PTUR, Reciproc and hand files in curved RCs and the percentage of remaining obturation material was not statistically different between the groups. Similarly, Azevedo Rios et al. [20] found no difference between the efficiency of the PTUR and Rec files on the residual obturation material in straight RCs. Bago et al. [7] compared the retreatment efficiency of the Reciproc 25, Reciproc Blue, PTUR and WaveOne Gold systems in curved canals and they reported no difference between the groups. The efficacy of the PTUR and Reciproc systems in oval shaped canals were evaluated during the removal of the initial RC obturation material in a previous study and the percentage of remaining material values were not significantly different in the coronal and middle sections and PTUR showed better performance in the apical region [1]. Özyürek et al. [21] found that PTUR was more effective than Rec25 in removing the RC obturation material. Similarly; PTUR and HF showed better performance than Rec25 to remove the obturation material and there was no difference between the PTUR and HF groups in our study. The reason for the better efficacy of PTUR might be as follows; large amounts of gutta-percha in spirals might be removed owing to the convex triangular cross sectional design of the PTUR files [9, 20] and this design transports the debris towards the RC ori [20, 22]. Also, The negative cutting-angle of PTUR file and the lack of radial-land might provide a cutting activity rather than a straightening action to the file [9]. Furthermore, RC anatomy, evaluation methods, and test designs might play a role in different study results. Beside these, operator related factors such as the intensity of brushing or other preparation motions and the determination of the working length during the obturation material removal might cause the differences between the study results.

Fenoul et al. [11] compared the retreatment efficacy of hand files and R-Endo files in single-rooted teeth and no differences were observed between the two techniques. In our study, the HF group showed better cleaning ability than the RE group in curved RCs. The use of #H files twice in the root canal and application of a circumferential, quarter-turn push and pull movement may have improved the efficacy of hand files. In addition, differences in root canal anatomy used in the studies may also lead to conflicting results.

Similar to our study results, Hassan et al. [23] reported that the XP-endo Shaper was significantly more effective than the R-Endo retreatment system in removing the RC obturation material. Iriboz et al. [24] found that the XPER system was more effective than the PTUR, hand files, and R25 in removing the obturation material. Similarly, Kapasi et al. [25] reported that XPS + XPF-R removed the RC filling more significantly than the PTUR and hand files. De-Deus et al. [26] compared the efficacy of the Reciproc, Reciproc Blue, and XP-endo Shaper files during RC filling removal procedures in mandibular incisors and found no difference between the Reciproc and XPS files. They used oval shaped RCs and this results were obtained before final re-preparation procedure. Differences between the operator experience, RC anatomy, retreatment procedure and the final preparation techniques of RCs after removing the obturation material, final preparation sizes, and variation in the evaluation methods might be responsible for conflicting results.

Mandibular molars have the lowest success rate after endodontic treatment and shaping of these teeth is more difficult and complicated owing to the curved RCs [2, 27, 28]. Hence, mandibular molar teeth with curved mesial RC were used to evaluate the retreatment efficiency of endodontic retreatment file systems in this study. During the retreatment procedure, RCs should be reshaped up to two sizes larger than the primary RC treatment to ensure the improved removal of obturation materials and a space for effective irrigation [15, 16, 29, 30]. Nevertheless, we need to avoid the excessive preparation of RC because of the weakening of the RC walls and susceptibility to perforation and vertical root fractures [15, 16]. Additionally, further enlargement can raise the risk of RC transportation and instrument fracture, especially in curved canals [31]. Considering the curvature and anatomy of lower mesial canals [32], RCs were enlarged to a larger apical size after removing the RC filling materials in our study (from #25 to #30).

The quantity of the remaining obturation material is assessed using several methods such as radiographic imaging, micro-CT, cone beam computed tomography (CBCT), and root sectioning for stereomicroscopic evalua [1, 5, 9, 11, 12, 20, 33]. Micro-CT is a non-invasive imaging method that provides to evaluate and analyze the filling material at different times of the experiment [13]. Also, it provides a quantitative evaluation of the tooth structure and filling materials with 3D high resolution images [13, 30]. Hence micro-CT was chosen to evaluate the remaining obturation material volume in our study.

In our study, mean times to reach the WL (T1) and to remove all obturation material (T2) were the longest in the HF group and the RE group was slower than the PTUR, Rec25, and XPER groups (P < 0.05). When T1 and T2 time values were compared, the XPER group showed faster removal of the RC obturation material than the REC25 and PTUR groups and also PTUR was slower than the Rec25. The tip designs and cross-sectional designs of files, amount of the files in the retreatment systems, and working kinematics of the file systems might be effective on the removing time of RC obturation materials. Similar to our study Zuolo et al. [34] found that TRUShape files which have triangular cross-section design removed RC filling material slower than Reciproc files. S-shaped cross-section of Reciproc files supplies better cutting efficiency than ProTaper files with a triangular cross-sectional design [35, 36]. Çanakcı et al. [37] compared the retreatment time of the Rec25, PTUR and RE file systems in lower premolar teeth and observed that REC25 was faster than other files and no difference was observed between the PTUR and RE groups. Different RC anatomies, using solvents for the removing of the obturation material, the size of apical preparation and also the operator-related variables might lead to differences between the results of these studies.

None of the five retreatment methods evaluated in our study could totally remove the RC obturation material. Further investigations are needed to evaluate more effective cleaning techniques and the supplementary systems to raise the success rate of endodontic non-surgical retreatment. This study was performed in controlled laboratory conditions only in the curved narrow root canals. Hence, the results of this study should not be adapted to the clinical conditions directly. Also, variations in the anatomic features of RC of lower molars is one of the limitations of this study. We aimed to compare the RC obturation material removal efficacy of XPER with other commonly used retreatment systems during the retreatment procedures. The limitation of the study design is that the systems have different tapers and tip sizes. Hence, we prepared the root canals with ProTaper Next X3 file to reduce the efficacy of this differences. More studies evaluating the clinical performance and post-operative pain or treatment success efficiency of the retreatment systems are needed. Also, further studies might be planned to assess the efficacy of the combination of the retreatment systems and supplementary use of irrigation activation systems to remove the all obturation material.

Conclusion

In conclusion, under the limitation of this ex-vivo research, the percentage of the remaining RC obturation material and residual RC obturation volume were lower in the PTUR, XPER and HF groups than in the RE and REC25 groups. The XPER retreatment system exhibited less T1 and T2 time values than the other retreatment systems while hand files show the most T1 and T2 values. As it provides effective RC filling removal in a shorter time, the XP-Endo Retreatment system might be advantageous for retreatment in curved RCs.

Data availability

The data that supports the findings of this study are available from corresponding author on reasonable request.

Abbreviations

CBCT:

Cone beam computed tomography

EDTA:

Ethylenediaminetetraacetic acid

micro-CT:

Micro-Computed tomography

NiTi:

Nickel-Titanium

NaOCl:

Sodium hypochlorite

RC:

Root canal

WL:

Working length

References

  1. Crozeta BM, Silva-Sousa YTC, Leoni GB, Mazzi-Chaves JF, Fantinato T, Baratto-Filho F, et al. Micro-Computed Tomography Study of Filling Material Removal from Oval-shaped Canals by Using Rotary, Reciprocating, and Adaptive Motion Systems. J Endod. 2016;42:793–7.

    Article  PubMed  Google Scholar 

  2. Kırıcı D, Demirbuga S, Karataş E. 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. J Endod. 2020;46:238–43.

    Article  PubMed  Google Scholar 

  3. Gomes ILL, Alves FRF, Marceliano-Alves MF, Silveira SB, Provenzano JC, Gonçalves LS. Canal transportation using Mani GPR or HyFlex NT during the retreatment of curved root canals: A micro-computed tomographic study. Aust Endod J. 2021;47:73–80.

    Article  PubMed  Google Scholar 

  4. Crozeta BM, Lopes FC, Menezes Silva R, Silva-Sousa YTC, Moretti LF, Sousa-Neto MD. Retreatability of BC Sealer and AH Plus root canal sealers using new supplementary instrumentation protocol during non-surgical endodontic retreatment. Clin Oral Investig. 2021;25:891–9.

    Article  PubMed  Google Scholar 

  5. Marques da Silva B, Baratto-Filho F, Leonardi DP, Henrique Borges A, Volpato L, Branco Barletta F. Effectiveness of ProTaper, D-RaCe, and Mtwo retreatment files with and without supplementary instruments in the removal of root canal filling material. Int Endod J. 2012;45:927–32.

  6. Alves FRF, Marceliano-Alves MF, Sousa JCN, Silveira SB, Provenzano JC, Siqueira JF. Removal of root canal fillings in curved canals using either reciprocating single- or rotary multi-instrument systems and a supplementary step with the XP-Endo Finisher. J Endod. 2016;42:1114–9.

    Article  PubMed  Google Scholar 

  7. Bago I, Plotino G, Katić M, Ročan M, Batinić M, Anić I. Evaluation of filling material remnants after basic preparation, apical enlargement and final irrigation in retreatment of severely curved root canals in extracted teeth. Int Endod J. 2020;53:962–73.

    Article  CAS  PubMed  Google Scholar 

  8. Machado AG, Guilherme BPS, Provenzano JC, Marceliano-Alves MF, Gonçalves LS, Siqueira JF, et al. Effects of preparation with the Self-Adjusting File, TRUShape and XP-endo Shaper systems, and a supplementary step with XP-endo Finisher R on filling material removal during retreatment of mandibular molar canals. Int Endod J. 2019;52:709–15.

    Article  CAS  PubMed  Google Scholar 

  9. Giuliani V, Cocchetti R, Pagavino G. Efficacy of ProTaper Universal Retreatment Files in Removing Filling Materials during Root Canal Retreatment. J Endod. 2008;34:1381–4.

    Article  PubMed  Google Scholar 

  10. Hussne RP, Braga LC, Berbert FLCV, Buono VTL, Bahia MGA. Flexibility and torsional resistance of three nickel-titanium retreatment instrument systems. Int Endod J. 2011;44:731–8.

    Article  CAS  PubMed  Google Scholar 

  11. Fenoul G, Meless GD, Pérez F. The efficacy of R-Endo® rotary NiTi and stainless-steel hand instruments to remove gutta-percha and Resilon. Int Endod J. 2010;43:135–41.

    Article  CAS  PubMed  Google Scholar 

  12. Topçuoǧlu HS, Demirbuga S, Tuncay Ö, Pala K, Arslan H, Karataş E. The effects of Mtwo, R-Endo, and D-RaCe retreatment instruments on the incidence of dentinal defects during the removal of root canal filling material. J Endod. 2014;40:266–70.

    Article  PubMed  Google Scholar 

  13. Volponi A, Pelegrine RA, Kato AS, Stringheta CP, Lopes RT, Silva AS de S, et al. Micro–computed Tomographic Assessment of Supplementary Cleaning Techniques for Removing Bioceramic Sealer and Gutta-percha in Oval Canals. J Endod. 2020;46:1901–6.

  14. Aktemur TS. The effect of XP-endo Finisher and XP-endo Finisher R supplementary files on apical debris extrusion during retreatment. Turkish Endod J. 2021;6:14–8.

    Google Scholar 

  15. Rödig T, Reicherts P, Konietschke F, Dullin C, Hahn W, Hülsmann M. Efficacy of reciprocating and rotary NiTi instruments for retreatment of curved root canals assessed by micro-CT. Int Endod J. 2014;47:942–8.

    Article  PubMed  Google Scholar 

  16. Azevedo MAD, da Silva TG, Fernandes Â, Piasecki L, Fariniuk LF, Neto UX da S. Endodontic retreatment using a single instrument from four nickeltitanium systems – a micro-ct study. Braz Dent J. 2020;31:605–10.

  17. Keleş A, Alcin H, Kamalak A, Versiani MA. Oval-shaped canal retreatment with self-adjusting file: A micro-computed tomography study. Clin Oral Investig. 2014;18:1147–53.

    Article  PubMed  Google Scholar 

  18. Schneider SW. A comparison of canal preparations in straight and curved root canals. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1971;32:271–5.

    Article  CAS  Google Scholar 

  19. Siqueira JF, Rôças IN, Ricucci D, Hülsmann M. Causes and management of post-treatment apical periodontitis. Br Dent J. 2014;216:305–12.

    Article  PubMed  Google Scholar 

  20. De Azevêdo RM, Villela AM, Cunha RS, Velasco RC, De Martin AS, Kato AS, et al. Efficacy of 2 reciprocating systems compared with a rotary retreatment system for gutta-percha removal. J Endod. 2014;40:543–6.

    Article  Google Scholar 

  21. Özyürek T, Demiryürek EÖ. Efficacy of different nickel-titanium instruments in removing gutta-percha during root canal retreatment. J Endod. 2016;42:646–9.

    Article  PubMed  Google Scholar 

  22. Saad AY, Al-Hadlaq SM, Al-Katheeri NH. Efficacy of Two Rotary NiTi Instruments in the Removal of Gutta-Percha During Root Canal Retreatment. J Endod. 2007;33:38–41.

    Article  PubMed  Google Scholar 

  23. Hassan HY, Hadhoud FM, Mandorah A. Retreatment of XP-endo Shaper and R-Endo files in curved root canals. BMC Oral Health. 2023;23:1–8.

    Article  Google Scholar 

  24. İriboz E, Bora T, Pehlivanoğlu E, Finisher E. The Efficiency of Hand-files, ProTaper R, Reciproc, XP-Endo Shaper and XP-Endo Finisher R in the Removal of Root Filling Material from Oval Root Canals. IOSR J Dent Med Sci e-ISSN. 2019;18:72–8.

    Google Scholar 

  25. Kapasi K, Kesharani P, Kansara P, Patil D, Kansara T, Sheth S. In vitro comparative evaluation of efficiency of XP-endo shaper, XP-endo finisher, and XP-endo finisher-R files in terms of residual root filling material, preservation of root dentin, and time during retreatment procedures in oval canals – A cone-beam co. J Conserv Dent. 2020;23:145.

    Article  PubMed  PubMed Central  Google Scholar 

  26. De-Deus G, Belladonna FG, Zuolo A de S, Cavalcante DM, Simões Carvalho M, Marinho A, et al. 3-dimensional Ability Assessment in Removing Root Filling Material from Pair-matched Oval-shaped Canals Using Thermal-treated Instruments. J Endod. 2019;45:1135–41.

  27. Gomes ILL, Alves FRF, Marceliano-Alves MF, Silveira SB, Sousa JCN, Provenzano JC, et al. Apical transportation using Mtwo or Reciproc retreatment systems in severely curved canals: a micro-computed tomographic study. Clin Oral Investig. 2023;27:1235–41.

    Article  PubMed  Google Scholar 

  28. Ricucci D, Russo J, Rutberg M, Burleson JA, Spngberg LSW. A prospective cohort study of endodontic treatments of 1,369 root canals: Results after 5 years. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2011;112:825–42.

    Article  PubMed  Google Scholar 

  29. Delai D, Jardine AP, Mestieri LB, Boijink D, Fontanella VRC, Grecca FS, et al. Efficacy of a thermally treated single file compared with rotary systems in endodontic retreatment of curved canals: a micro-CT study. Clin Oral Investig. 2019;23:1837–44.

    Article  PubMed  Google Scholar 

  30. Faus-Matoses V, Pasarín-Linares C, Faus-Matoses I, Foschi F, Sauro S, Faus-Llácer VJ. Comparison of obturation removal efficiency from straight root canals with protaper gold or reciproc blue: A micro-computed tomography study. J Clin Med. 2020;9:1–9.

    Article  Google Scholar 

  31. da Rosa RA, Santini MF, Cavenago BC, Pereira JR, Duarte MAH, Só MVR. Micro-CT evaluation of root filling removal after three stages of retreatment procedure. Braz Dent J. 2015;26:612–8.

    Article  PubMed  Google Scholar 

  32. de Castro RF, Melo J do SS, de Lima Dias Junior LC, Silva EJNL, da Silva Brandão JM. Evaluation of the efficacy of filling material removal and re-filling after different retreatment procedures. Braz Oral Res. 2018;32:1–7.

  33. Ajina MA, Shah PK, Chong BS. Critical analysis of research methods and experimental models to study removal of root filling materials. Int Endod J. 2022;55:119–52.

    Article  PubMed  Google Scholar 

  34. De Siqueira ZA, Zuolo ML, Da Silveira Bueno CE, Chu R, Cunha RS. Evaluation of the Efficacy of TRUShape and Reciproc File Systems in the Removal of Root Filling Material: An Ex Vivo Micro-Computed Tomographic Study. J Endod. 2016;42:315–9.

    Article  Google Scholar 

  35. Fruchi LDC, Ordinola-Zapata R, Cavenago BC, Hungaro Duarte MA, Da Silveira Bueno CE, De Martin AS. Efficacy of reciprocating instruments for removing filling material in curved canals obturated with a single-cone technique: A micro-computed tomographic analysis. J Endod. 2014;40:1000–4.

    Article  PubMed  Google Scholar 

  36. Bürklein S, Hinschitza K, Dammaschke T, Schäfer E. Shaping ability and cleaning effectiveness of two single-file systems in severely curved root canals of extracted teeth: Reciproc and WaveOne versus Mtwo and ProTaper. Int Endod J. 2012;45:449–61.

    Article  PubMed  Google Scholar 

  37. Çanakçi BC, Ustun Y, Er O, Genc SO. Evaluation of apically extruded debris from curved root canal filling removal using 5 nickel-titanium systems. J Endod. 2016;42:1101–4.

    Article  PubMed  Google Scholar 

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Acknowledgements

This study was an Endodontics specialty thesis of Eren Orhan and was financially supported (in purchasing materials and Micro-CT scannings) by the Eskisehir Osmangazi University Scientific Research Projects Coordination Unit (Project Number: 202045A208). The authors would like to thank to Dr. Yasin ALTAY from Eskisehir Osmangazi University, Faculty of Agriculture for statistical analysis.

Funding

This study (in purchasing materials) was financially supported by the Eskisehir Osmangazi University Scientific Research Projects Coordination Unit ((Project Number: 202045A208).). This research received no external funding.

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Authors and Affiliations

  1. Department of Endodontics, Eskisehir Osmangazi University, Faculty of Dentistry, Odunpazarı, Eskişehir, 26480, Turkey

    Eren Orhan & Betul Gunes

  2. Department of Dentomaxillofacial Radiology, Ankara University, Faculty of Dentistry, Yenimahalle, Ankara, 06560, Turkey

    Kaan Orhan

  3. Department of Anatomy, Ankara University, Faculty of Dentistry, Ankara, Yenimahalle, Turkey

    Mert Ocak

Authors
  1. Eren Orhan
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  2. Kaan Orhan
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  4. Betul Gunes
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Contributions

Authors’ Contribution EO: Conceptualization, Investigation, and Performing the experiments K.O.: Evaluation of the images and the reviewing the manuscript M.O.: Evaluation of the images, preparing the figures, B.G.: Conceptualization, Investigation, Performing the experiments, and Writing the manuscript text.

Corresponding author

Correspondence to Betul Gunes.

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Ethics approval and consent to participate

The study was conducted in accordance with the Declaration of Helsinki, and aproved by the Ethics Committee of Eskisehir Osmangazi University (10.12.2019/36). All participants gave informed consent to participate.

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Not applicable.

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The authors declare no competing interests.

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Orhan, E., Orhan, K., Ocak, M. et al. Comparing the root canal filling removal efficiency of XP-endo retreatment system with hand Files, R-endo, reciproc and protaper universal retreatment systems in curved root canals: a micro-CT study. BMC Oral Health 25, 544 (2025). https://doiorg.publicaciones.saludcastillayleon.es/10.1186/s12903-025-05849-y

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Keywords

BMC Oral Health

ISSN: 1472-6831

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