May 04, 2026

Comparative Evaluation of XP-endo Retreatment, D-RaCe, and Fanta Retreatment Systems in Removing Gutta-Percha and Bioceramic Sealer: A Randomized In Vitro Study

DOI
https://dx.doi.org/10.17504/protocols.io.j8nlkzq75l5r/v1
  • Marina Mamdoh Kamal Antonyous1,2,3,
  • Prof.Dr. Alaa Abdelsalam Elbaz4,
  • Dr.Ghada Ihab ElWazan5
  • 1Cairo University, Egypt;
  • 2Faculty of Dentistry;
  • 3Master’s degree student, Department of Endodontics, Faculty of Dentistry, Cairo University;
  • 4Professor of Endodontics, Faculty of Dentistry, Cairo University;
  • 5Lecturer, Department of Endodontics, Faculty of Dentistry, Cairo University
  • Faculty of Dentistry, Cairo University
Marina Mamdoh Kamal
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DOI: https://dx.doi.org/10.17504/protocols.io.j8nlkzq75l5r/v1
Protocol Citation: Marina Mamdoh Kamal Antonyous, Prof.Dr. Alaa Abdelsalam Elbaz, Dr.Ghada Ihab ElWazan 2026. Comparative Evaluation of XP-endo Retreatment, D-RaCe, and Fanta Retreatment Systems in Removing Gutta-Percha and Bioceramic Sealer: A Randomized In Vitro Study. protocols.io https://dx.doi.org/10.17504/protocols.io.j8nlkzq75l5r/v1
License: This is an open access  protocol  distributed under the terms of the  Creative Commons Attribution License,  which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: Working
We use this protocol and it's working
Created: May 02, 2026
Last Modified: May 04, 2026
Protocol  Integer ID: 316201
Keywords: fanta retreatment systems in removing gutta, bioceramic sealer removal, teeth after retreatment, extracted teeth, bioceramic sealer, fanta af retreatment systems on the removal, deep penetration into dentinal tubule, removing gutta, effectiveness of gutta, dentinal tubule, fanta retreatment system, fanta af retreatment system, fanta af retreatment systems in conjunction, activated irrigant, endo retreatment, retreatment file, randomized in vitro study
Abstract
To our knowledge there are no studies in the literature comparing the efficiency of XP-Endo, D –Race, and Fanta AF retreatment systems on the removal of bioceramic sealer and gutta-percha. Bioceramic sealers are known for their strong adhesion and deep penetration into dentinal tubules, which makes retreatment particularly challenging, yet evidence on the combined role of retreatment files and activated irrigant remains scarce. Therefore, the aim of this study is to evaluate the effectiveness of gutta-percha and bioceramic sealer removal in single-rooted, single-canalled extracted teeth after retreatment using XP-Endo, D-Race, and Fanta AF retreatment systems in conjunction with ultrasonically activated irrigants (NaOCl 26 17% EDTA).
Safety warnings
Prolonged use or higher concentrations of chelating agents may cause erosion of dentin, so clinical protocols recommend limited exposure times to preserve tooth structure.
Ethics statement
Research ethics approval
Review of literature
Zehnder (2006) This review summarized the chemistry and roles of common irrigants, particularly sodium hypochlorite (NaOCl) and chelators. NaOCl was highlighted as essential for dissolving organic tissue and providing antimicrobial action, but it cannot remove inorganic smear layer. The author concluded that combined protocols using NaOCl with a chelating agent such as EDTA or citric acid are necessary to achieve comprehensive canal cleanliness.
Donnermeyer et al. (2019) This systematic review synthesized the properties of calcium silicate sealers, including composition, setting, solubility, and bioactivity. The authors found that bioceramic sealers are biocompatible and bioactive but exhibit formulation-dependent physical behaviour, including slight solubility. They highlighted the lack of clinical outcome data and noted that while bioceramics bond chemically and penetrate dentinal tubules, these same properties make retreatment more difficult.
Mohammadi et al. (2019) This review compared smear layer removal agents including EDTA, citric acid, MTAD, maleic acid, and QMix. The authors found that EDTA and citric acid remain effective standards, though some newer agents equal or exceed EDTA in specific contexts. The conclusion reinforced the need for chelation beyond NaOCl for comprehensive cleaning.
Rajda et al. (2021) This micro-CT study quantified residual volumes after retreatment of canals filled with TotalFill BC (bioceramic) versus AH Plus (epoxy resin) using Reciproc instruments. The bioceramic sealer/gutta-percha group showed lower residual volume than the epoxy resin group, but no technique achieved complete removal. The authors concluded that instrument–material interactions influence retreatment outcomes, and while bioceramic is not always harder to remove volumetrically, microstructural residues persist.
Abo El Magd et al. (2022) conducted an in vitro study to compare three rotary retreatment systems: Fanta AF, ProTaper Universal, and M3 ProGold. The researchers evaluated each system’s efficiency in removing root canal filling materials, the time required for retreatment, the amount of debris extruded, and the incidence of instrument fracture. The results showed that both Fanta AF and M3 ProGold were more efficient at removing obturating material than ProTaper Universal. However, ProTaper Universal completed the retreatment procedures in the shortest time. Fanta AF was associated with greater debris extrusion compared to the other systems, while fracture rates varied depending on the file design and system used. The authors concluded that Fanta AF is an effective and reliable option for retreatment, offering high efficiency in material removal. However, clinicians should be aware of its tendency to extrude more debris, which represents a trade-off that must be considered in clinical decision-making.
Ravindran et al. (2024) conducted an in vitro investigation using cone-beam computed tomography (CBCT) to compare the effectiveness of the D-RaCe retreatment file system with Hero Shaper rotary files in removing root canal obturation material. Ninety maxillary premolars were prepared and obturated with gutta-percha and bioceramic sealer, then subjected to retreatment with either system. Volumetric analysis revealed that the D-RaCe system achieved significantly greater removal of obturation material compared to Hero Shaper, although neither system was able to completely eliminate gutta-percha and sealer remnants. The authors concluded that while D-RaCe demonstrated superior efficacy in bulk material removal, residual obturation persisted, underscoring the need for supplementary techniques to achieve thorough canal cleanliness.
Verdugo Balcázar 6 Carrillo Rengifo (2025) This study investigated whether using additional cleaning systems after retreatment with Fanta AF files could improve the removal of bioceramic sealer. Two adjuncts were tested: the XP-Endo Finisher and the AF Max 1, compared against a control group with no adjunct. Both adjuncts improved sealer removal compared to the control, but there was no statistically significant difference between them overall. A slight trend favored the XP-Endo Finisher in the cervical third, while the apical third remained the most difficult area to clean in all groups. The authors concluded that complementary cleaning systems can enhance retreatment outcomes, but none achieved complete removal, and effective cleaning of the apical third still requires combining mechanical and chemical strategies.
Farias Silva et al. (2025) This study tested combinations of reciproc instruments with different activation adjuncts in canals filled with BioC Sealer. The results showed that both Irsonic and XP-Endo Finisher R significantly enhanced canal cleanliness after retreatment, while Flatsonic did not provide additional benefit. The authors concluded that ultrasonic and adjunct activation methods improve removal of bioceramic sealer remnants, although not all inserts are equally effective.
Ckırık 6 Yusufoğlu (2025) The authors compared final irrigation activation methods after retreatment of canals filled with BioSerra or MTA Fillapex. EDDY significantly improved removal of MTA Fillapex across all canal sections, while Ultra-X was superior for BioSerra in the middle and apical thirds. The study concluded that the choice of activation method should be tailored to the type of sealer used, as different systems show varying effectiveness depending on the material.
Haichal et al. (2025) This study compared three irrigant protocols—phosphoric acid 37%, EDTA 17% with ultrasonic activation, and Triton with activation—after retreatment of canals filled with Cerasal. The findings showed that EDTA with ultrasonic activation was statistically more effective overall than phosphoric acid or Triton. None of the protocols achieved complete removal, and performance varied depending on the obturation technique and canal third. The authors concluded that EDTA combined with activation remains a strong standard protocol for bioceramic retreatment.
Orhan et al. (2025) conducted a micro-CT study to compare the efficacy of several retreatment systems, including the XP-Endo Retreatment file, in removing root canal filling materials. Sixty mandibular molars with mesial root curvature between 20º and 40º were prepared with ProTaper Next and obturated using gutta-percha and AH Plus sealer. The teeth were divided into five groups: ProTaper Universal Retreatment (PTUR), Reciproc R25 (REC25), R-Endo (RE), XP-Endo Retreatment (XPER), and hand files with Gates Glidden burs (HF). The study measured both the time required to reach working length (T1), the time to complete filling removal (T2), and the residual obturation volume using micro-CT. Results showed that PTUR, XPER, and HF groups left less residual material than RE and REC25. The XP-Endo system also demonstrated shorter retreatment times (T1 and T2) compared to other rotary systems, while hand files required the longest times. The authors concluded that XP-Endo is an efficient retreatment system, capable of reducing residual filling volume and improving time efficiency compared to several conventional systems.
Introduction
Nonsurgical root canal treatment success rates consistently exceed 85–95% under controlled clinical conditions (Ng et al., 2011; Al Jallad et al., 2025). Nonetheless, failure occurs in a subset of cases, primarily due to persistent infection or reinfection, necessitating retreatment aimed at eliminating residual microbial contamination and reestablishing periapical health Successful retreatment critically depends on the complete removal of previous root canal filling materials, including gutta‑percha and bioceramic sealer, which if left behind, compromise thorough disinfection and sealing (Roshdy & AbdelWahed, 2021).
Bioceramic sealers, based on calcium silicate chemistry, have gained prominence in endodontics due to their bioactivity, chemical bonding to dentin, and ability to release calcium hydroxide, which promotes hydroxyapatite formation and enhances the seal at the dentin–sealer interface (Candeiro et al., 2012; Gandolfi et al., 2013; Donnermeyer et al., 2019). Their penetration into dentinal tubules and dimensional stability contribute to superior sealing and reduced microleakage, while their high biocompatibility and antimicrobial properties support periapical healing (Zhang et al., 2009; Camilleri, 2014).

However, these same properties that make bioceramic sealers clinically advantageous also create significant challenges during retreatment. Their strong adhesion to dentin and deep intratubular penetration hinder complete removal, even when advanced rotary systems and activation protocols are employed (Zuolo et al., 2016; Silva et al., 2019). Residual bioceramic material can compromise canal disinfection and re‑obturation, making retreatment of bioceramic‑obturated cases more complex compared to resin‑based sealers. This duality underscores both the importance of bioceramic sealers in primary treatment and the necessity of optimized retreatment strategies when failure occurs.

Advances in endodontic instrumentation have introduced rotary nickel–titanium (NiTi) file systems specifically designed for retreatment. The XP‑endo Retreatment system, manufactured with MaxWire alloy, demonstrates adaptive expansion within canal morphology and has shown efficient removal of filling materials with reduced procedural errors. Multiple micro‑CT and in vitro studies confirm its supplementary effectiveness, although complete removal of obturation material remains challenging (Silva et al., 2018; Orhan et al., 2025).

Clinical and laboratory investigations have also assessed the Fanta AF retreatment system. In vitro comparisons with ProTaper Universal and M3 ProGold files demonstrated that Fanta AF achieved efficient gutta‑percha removal and canal reshaping, with favorable safety outcomes including lower instrument separation rates and enhanced cyclic fatigue resistance (Abo El Magd et al., 2022). These properties make Fanta AF a reliable option for retreatment procedures requiring conservative yet thorough removal of obturation materials.

Sodium hypochlorite (NaOCl) remains the cornerstone irrigant for its potent antimicrobial and tissue‑dissolving properties, and recent studies confirm its positive influence on bond strength values (İlkgelen & İriboz, 2024; Zehnder, 2006). However, NaOCl alone cannot effectively remove the inorganic components and smear layer associated with bioceramic sealers.

Supplemental chelating agents such as ethylenediaminetetraacetic acid (EDTA) or citric acid are required to achieve optimal cleanliness of dentinal walls and tubules. Moreover, activation protocols significantly enhance irrigant efficacy. Passive ultrasonic irrigation and newer sonic systems (EDDY, Ultra-X) have demonstrated superior removal of bioceramic sealer remnants, particularly in the apical third.
EDTA acts as a chelating agent by removing the smear layer and decalcifying dentin, which facilitates the removal of mineralized bioceramic sealers. Concentrations around 17% have been shown to strike a balance between effectively softening sealer remnants and preserving the dentin substrate.
Chelating agents like EDTA improve the penetration and bonding of bioceramic sealers to root dentin by eliminating the smear layer and altering the mineral content of the dentin surface, thereby enhancing sealer adaptation.

However, prolonged use or higher concentrations may cause erosion of dentin, so clinical protocols recommend limited exposure times to preserve tooth structure. This balance allows for better retreatment outcomes by promoting sealer removal without compromising dentin integrity.
To our knowledge there are no studies in the literature comparing the efficiency of XP‑Endo, D –Race, and Fanta AF retreatment systems on the removal of bioceramic sealer and gutta‑percha. Bioceramic sealers are known for their strong adhesion and deep penetration into dentinal tubules, which makes retreatment particularly challenging, yet evidence on the combined role of retreatment files and activated irrigant remains scarce. Therefore, the aim of this study is to evaluate the effectiveness of gutta‑percha and bioceramic sealer removal in single‑rooted, single‑canalled extracted teeth after retreatment using XP‑Endo, D-Race, and Fanta AF retreatment systems in conjunction with ultrasonically activated irrigants (NaOCl & 17% EDTA)
Specific objectives
Research question: Which retreatment system is the most effective and efficient in removing gutta-percha and bioceramic sealer?
Null Hypothesis: There are no significant differences in removal efficiency, apical extrusion, or removal time among the tested retreatment systems.
PICO
Population: Extracted, decoronated human single-rooted teeth obturated with gutta-percha and calcium silicate-based sealer.
Intervention:
I1: Retreatment using XP Endo Retreatment kit
I2: Retreatment using Fanta retreatment kit
Comparator: Retreatment using D-RaCe retreatment kit
Outcomes:
O1: Gutta percha and bioceramic sealer remnants on canal walls
O2: Apical Debris Extrusion
O3: Retreatment Procedural Time
Prioritization Of Outcome Outcome Method of Measurement Unit of measurement
Primary Outcome Gutta percha and bioceramic sealer remnants on canal walls Stereomicroscope (Ali et al., 2019) Comparative Assessment of Manual, Rotary and Reciprocating Instruments for Removal of Root Fillings, Using Stereomicroscope: An in Vitro Study Percentage
Secondary Outcome Code 3-3-1 Apical Debris Extrusion Digital balance (Analytical) (Morsy, D. et al., 2022) Gram
Tertiary Outcome Retreatment Procedural Time. Digital Stopwatch (Kumar et.al 2024) Minutes & Seconds
Materials and Methods
1) Sample:
    Calculated sample size:
We are planning a study of a continuous response variable in three independent experimental groups. Based on a previous study with an estimated standard deviation of 10 and an expected effect size of 12, a sample size of 15 teeth per group was calculated to achieve a statistical power of 80% at a significance level of 0.05, resulting in a total sample size of 45 teeth.
Sample description:
45 single rooted teeth extracted owing to orthodontic, periodontal, or prosthodontic reasons were collected from the Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Cairo University.
Eligibility Criteria
Inclusion Criteria
  • Tooth type: Extracted human permanent teeth with a single root and a single canal.
  • Apical maturity: Fully formed apex with closed apical foramen.
  • Canal morphology: Straight canals with curvature <10° (Schneider), no visible canal bifurcations.
  • Root length: Adequate length after decoronation to achieve a standardized 16 mm working segment.
  • Pre‑operative status: No prior endodontic treatment, posts, or restorations affecting the root structure.
  • Structural integrity: Intact roots without visible cracks, fractures, or external defects
  • Radiographic confirmation: No internal resorption, calcifications, or perforations.
Exclusion Criteria
  • Anatomical complexity: More than one canal, isthmuses, canal bifurcation, or severe curvature ≥10°.
  • Developmental or pathological changes: Open apex, internal/external resorption, extensive calcification, or root anomalies.
  • Previous interventions: Any history of endodontic treatment, retreatment, post placement, or chemical canal modification.
  • Structural compromise: Root cracks, fractures, craze lines, or caries extending to the root that compromise instrumentation or obturation.
Sample Preparation
Extracted human permanent single‑rooted teeth were collected from university clinics for orthodontic, prosthodontic and periodontal reasons and ethical approval was obtained in accordance with institutional guidelines and the Declaration of Helsinki.
Cleaning and Storage
Soft tissue remnants were mechanically removed, and teeth were stored in saline solution at 4–8°C until use, before instrumentation, teeth were rinsed thoroughly with distilled water to eliminate residual saline
Standardization of Root Length
Crowns were decoronated using a diamond disc under water cooling to obtain a standardized root length of 16 mm,following the methodology of Olivieri et al. (2016).
Canal Patency and Working Length: A size 10 K‑file was introduced into the canal until visible at the apical foramen. The working length was established 1 mm short of the apical foramen, consistent with the approach of Cıkrık & Yusufoğlu (2025).
Initial Canal Preparation and Obturation
  • Canals will be prepared to a standardized apical size (#40/.04 taper) using rotary NiTi instruments.
  • Irrigation was performed with 5.25% NaOCl during instrumentation, followed by a final rinse with 17% EDTA to remove the smear layer (Zehnder, 2006; Gandolfi et al., 2013).
  • Canals will be obturated with gutta‑percha cones and a bioceramic sealer (WellRoot ST), using the single‑cone technique
  • Specimens were stored at 37°C and 100% humidity for 7 days to allow complete sealer setting
Intervention:
For Groups of XP endo rise retreatment files (FKG Dentaire, LA CHAUX-DE-FONDS, Switzerland):
· DR1 file will be used at 800 rpm and 1.5 Ncm torque into theobturation material to create a starting point for the XP-endo Rise Shaper tip. The active tip of DR1 will be used to facilitate the initial penetration. This is followed by XP-endo Rise Shaper at 1000 rpm - 1 Ncm. until working length or the end of the previous filling material is reached. The Finisher R will then be used for at least 1 minute
For D-Race retreatment kits(FKG Dentaire, LA CHAUX-DE-FONDS, Switzerland):
· DR1 instrument of D- Race retreatment (size 30, taper .10, length 15 mm)  will be used at high speed (around 800–1,000 rpm) with light apical pressure and a brushing motion to create a solvent path and clear coronal obstructions then DR2 instrument (size 25, taper .04, length 25 mm) is used at speed (400–600 rpm) and torque (≈1.5 Ncm) to reach working length and remove filling material from the apical third.
For the Fanta retreatment kits:
· Use of the Fanta #30 File in coronal third at 300–350 rpm with a torque 2.0 Ncm. establishing a straight‑line path for subsequent instrumentation, Use of the Fanta #25 File for middle third (tip size 25, taper .08, length 18 mm) operated under the same motor settings, Use of the Fanta #20 File for apical third: (tip size 20, taper .07, length 22 mm), at the same rotational speed and torque, the #20 file will complete the retreatment sequence by removing residual filling material apically and ensuring canal patency.
· Irrigation with 5.25% NaOCl, separated by saline then followed by 17% EDTA will be ultrasonically activated (passive ultrasonic irrigation for 3 cycles × 20 seconds each) to optimize sealer dissolution and smear layer removal for all samples
· If full WL isn't reached, small hand files (C files, C+files) will be used.
· Retreatment time recorded from file insertion to canal cleanliness confirmation via x-ray
· Final rinse with distilled water
· Apical debris extrusion: Eppendorf tubes that have their caps removed will be weighed and used for each tooth. The tooth will be attached to removed tube cap and placed over the tube to complete the retreatment procedure after which the tube cover and tooth will be removed again, Tubes will be weighted post instrumentation to measure extruded debris using an analytical balance.
Group Retreatment System Irrigant Protocol
1 XPR - E 5.25% NaOCl + 17% EDTA
2 D-R - E 5.25% NaOCl + 17% EDTA
3 FR - E 5.25% NaOCl + 17% EDTA
Outcome Measures
Primary outcome:
The primary outcome of the present study will be the percentage of root canal wall surface area covered by residual gutta‑percha and bioceramic sealer following endodontic retreatment using a stereomicroscope under standardised magnification. This evaluation method will be employed to enable assessment of visible surface remnants of obturation materials on the canal walls (Ali et al., 2019)
Specimen Sectioning
Roots will be externally grooved with a diamond disc and split longitudinally with a chisel to expose canal walls without altering the internal surface. Each specimen will be divided into coronal, middle, and apical thirds to standardize evaluation sites (Ali et al., 2019; Donnermeyer et al., 2018; Kaćunić et al., 2022; Hülsmann et al., 1997).
Quantitative Image Analysis
Quantitative evaluation will be carried out using image analysis software (ImageJ, National Institutes of Health, Bethesda, USA). For each canal third, the total visible canal wall surface area will be defined, and the area covered by residual gutta‑percha and/or bioceramic sealer will be identified using uniform thresholding criteria. The extent of remaining filling material will be calculated and expressed as a percentage of the total canal wall surface area, reflecting the area covered by obturation remnants(Ali et al., 2019; Donnermeyer et al., 2018; Kaćunić et al.,2022)
Secondary Outcome
Eppendorf tubes that have their caps removed will be weighed and used for each tooth. The tooth will be attached to removed tube cap and placed over the tube to complete the retreatment procedure after which the tube cover and tooth will be removed again, Tubes will be weighted post instrumentation to measure extruded debris using an analytical balance. (Burbano Balseca et al., 2019; Morsy,D. et al., 2022)
Tertiary Outcome
The tertiary outcome will be the retreatment time, measured in minutes & seconds from the initial engagement of the retreatment instrument until complete removal of gutta‑percha is confirmed radiographically and visually, consistent with the approach of Asiri (2024). All time measurements will be performed by a single operator (Zmener  et al 2007).
Prioritization Of Outcome Outcome Method of Measurement Unit of measurement
Primary Outcome Gutta percha and bioceramic sealer remnants on canal walls Stereomicroscope (Ali et al., 2019) Comparative Assessment of Manual, Rotary and Reciprocating Instruments for Removal of Root Fillings, Using Stereomicroscope: An in Vitro Study Percentage
Secondary Outcome Code 3-3-1 Apical Debris Extrusion Digital balance (Analytical) (Morsy, D. et al., 2022) Gm
Tertiary Outcome Retreatment Procedural Time. Digital Stopwatch (Kumar et.al 2024) Minutes & Seconds
B) Assignment to intervention:
Sequence generation
Randomization and sequence generation will be carried out using a computer based random sequence generator (https://www.random.org), where the samples (n = 45) will be randomly distributed into three groups (n = 15).
Allocation concealment
To minimize selection bias in the intervention, the allocation sequence will be secured and concealed until assignment by placing the teeth in sequentially numbered opaque sealed envelopes.
 Implementation
 Random allocation, sequence generation, and allocation concealment will be conducted by the Co-supervisor.
C. Blinding
To avoid detection bias, images will be taken and analyzed via software by two trained, blinded observers who will be unaware of the allocation sequence, and they will generate the outcome reports. Both the outcome assessor and the statistician will be blinded to the group allocations.
Statistical Methods
All data generated during the study will be recorded, tabulated, and statistically analysed using appropriate statistical software
Descriptive statistics will be used to summarise the data. Continuous variables, including the percentage of root canal wall surface area covered by residual gutta‑percha and bioceramic sealer, will be expressed as mean and standard deviation for normally distributed data, or as median and interquartile range for non‑normally distributed data.
Prior to inferential analysis, data will be assessed for distribution characteristics. The choice of statistical tests will be determined based on the distribution of the data and the homogeneity of variances.
Ethics
The research will be admitted to the ethics committee for review. After receiving the results and finishing the experiment all instruments and teeth samples will be sterilized and discarded in special incinerator under the supervision of Microbiology Department- Cairo university.
Bibliography
Abo El Magd IAH, Hussein S, Abdelaziz T. Efficacy of three different rotary Ni‑Ti instruments in removing gutta‑percha during root canal retreatment (in vitro study). Egypt Dent J. 2022;68(2):2533‑42.
  • AlBatati F, AbuMostafa N. Comparative evaluation of smear layer removal and dentin erosion using EDTA, citric acid, and QMix. PLoS One. 2024;19(3):e0298765.
  • Ali, A., Hussain, S., Metgud, S., Mishra, S., Sharma, A., & Gupta, N. (2019). Comparative Assessment of Manual, Rotary and Reciprocating Instruments for Removal of Root Fillings, Using Stereomicroscope: An in Vitro Study. Bangladesh Medical Research Council Bulletin, 45(1), 54–61.
  • Al Jallad N, Sun E, Wu T, Cui S, Basmaji A, Thakkar R, et al. The success of endodontic treatments performed by dental residents in advanced education in general dentistry program: a 10‑year retrospective study. Dent J. 2025;13(7):306.
  • Burbano Balseca MJ, Terán Ayala SB, da Costa Aznar FD, de Freitas-Aznar AR, Aguirre Balseca GM, Freitas KMS. In vitro comparison of apically extruded debris during root canal retreatment with rotary and reciprocating systems. Open Dent J. 2019;13:488‑492.
  • Camilleri J. Sealers and root canal filling materials. Aust Dent J. 2014;59(Suppl 1):103‑13.
  • Candeiro GTM, Correia FC, Duarte MAH, Ribeiro MA, Gavini G. Evaluation of radiopacity, pH, and calcium ion release of a bioceramic root canal sealer. J Endod. 2012;38(4):493‑7.
  • Cıkrık BN, Yusufoğlu SI. Efficacy of irrigation activation methods in removal of bioceramic‑based sealer in retreatment. Odontology. 2025;113(8):1119‑27.
  • Donnermeyer D, Vahdat‑Pajouh N, Schäfer E, Dammaschke T. Properties of calcium silicate‑based sealers: a narrative review. Materials. 2019;12(15):2533.
  • Donnermeyer, D., Bunne, C., Schäfer, E., & Dammaschke, T. (2018). Retreatability of three calcium silicate-containing sealers and one epoxy resin-based root canal sealer with four different root canal instruments. Clinical Oral Investigations, 22(2), 811–817.
  • Farias‑Silva CB, Limoeiro AG, Gouveia P, Marceliano‑Alves M, Fontana CE, Pelegrine RA, et al. Efficacy of Irrisonic, XP‑Endo Finisher R, and Flatsonic in bioceramic sealer removal: a micro‑CT study. Clin Oral Investig. 2025;29:243.
  • Gandolfi MG, Siboni F, Prati C. Chemical‑physical properties of calcium silicate‑based cements for endodontics and restorative dentistry. Int Endod J. 2013;46(10):908‑18.
  • Haichal WS, Pontoriero DIK, Ferrari Cagidiaco E, Verniani G, Ferrari M. Evaluation of the efficiency of different irrigation materials to remove bioceramic sealer in endodontic retreatment. J Osseointegration. 2025;17(3):125‑30.
  • Hülsmann M, Rümmelin C, Schäfers F. Root canal cleanliness after preparation with different endodontic instruments. J Endod. 1997;23(1):1‑6.
  • İlkgelen B, İriboz E. Effect of different irrigants on bond strength of bioceramic sealer Bioserra. Eur Endod J. 2024;9(2):85‑92.
  • Kaćunić, D. J., Tadin, A., Dijanić, P., Katunarić, A., Matijević, J., Trutina-Gavran, M., & Galić, N. (2022). Efficacy of Reciprocating Instruments in Retreatment of Bioactive and Resin-Based Root Canal Sealers. Acta Stomatologica Croatica, 56(4), 338–350.
  • Kumar SK, Kumar M, Sharma N, Arora P, Bhatt M, Akkanapally S. Comparative Evaluation of the Efficacy of Different Ni-Ti Rotary Instruments in Removal of Gutta-Percha During Root Canal Retreatment: An in vitro Study. Cureus. 2024;16(5):e24819.
  • Mohammadi Z, Shalavi S, Yaripour S, Kinoshita J, Manabe A, Kobayashi M, et al. Smear layer removing ability of root canal irrigation solutions: a review. J Contemp Dent Pract. 2019;20(3):395‑402.
  • Morsy, D., Abouelenien, S. Assessment of apically extruded debris during root canal retreatment using two different file kinematics (An in-vitro study). Egyptian Dental Journal, 2022; 68(4): 3981-3988.
  • Ng YL, Mann V, Gulabivala K. A prospective study of the factors affecting outcomes of nonsurgical root canal treatment: part 2: tooth survival. Int Endod J. 2011;44(7):610‑25.
  • Olivieri JG, Duran‑Sindreu F, Mercadé M, Roig M. Influence of root canal length standardization on retreatment studies. J Endod. 2016;42(2):284‑288
  • Orhan E, Orhan K, Ocak M, Gunes B. 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. 2025;25:544.
  • Prado M, Gusman H, Gomes BPFA, Simão RA. Efficacy of EDTA and citric acid on smear layer removal. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2010;109(5):e70‑6.
  • Rajda PJ, Ozcelik B, Ceyhanli KT, Erdilek N, Ozkocak I, Serefoglu B. Micro‑CT evaluation of retreatability of bioceramic and epoxy resin‑based sealers. Aust Endod J. 2021;47(2):20‑9.
  • Ravindran R, Ramesh S, Kumar A, Priya K, Senthilkumar B. Comparative evaluation of D‑Race and Hero Shaper systems in removing obturation material using CBCT. J Conserv Dent. 2024;27(2):150‑156
  • Roshdy NN, AbdelWahed A. Effectiveness of gutta‑percha/bioceramic sealer removal during retreatment using different irrigation protocols. Egypt Dent J. 2021;67:893‑903.
  • Silva EJNL, Belladonna FG, Zuolo AS, Rodrigues E, Ehrhardt IC, Souza EM, et al. Effectiveness of XP‑endo Finisher and XP‑endo Finisher R in removing root filling remnants. Int Endod J. 2018;51(1):86‑91
  • Silva EJNL, Carapiá MF, Lopes RT, Belladonna FG, Moreira EJL, De‑Deus G. Micro‑CT evaluation of retreatment techniques for bioceramic and resin‑based sealers. Int Endod J. 2019;52(6): 1‑10
  • Verdugo Balcázar JC, Carrillo Rengifo J. Effectiveness of XP‑Endo Finisher and AF Max 1 as adjuncts after Fanta AF retreatment. Restaur Dent Endod. 2025;50(1):1‑9.
  • Zhang W, Li Z, Peng B. Assessment of a new root canal sealer’s apical sealing ability. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009;107(6):e79‑82.
  • Zmener O, Pameijer CH, Banegas G. Retreatment efficacy of hand versus automated instrumentation in oval‑shaped root canals: an ex vivo study. Int Endod J. 2006;39:521‑6.
  • Zuolo AS, Mello JE Jr, Cunha RS, Zuolo ML, Bueno CE. Efficacy of reciprocating and rotary techniques for removing filling material during root canal retreatment. Int Endod J. 2016;49(11):1079‑1085.
Protocol references
Ng et al., 2011; Al Jallad et al., 2025; Roshdy 26 AbdelWahed, 2021; Candeiro et al., 2012; Gandolfi et al., 2013; Donnermeyer et al., 2019; Zhang et al., 2009; Camilleri, 2014; Zuolo et al., 2016; Silva et al., 2019; Silva et al., 2018; Orhan et al., 2025; Abo El Magd et al., 2022; Ilkgelen 26 Iriboz, 2024; Zehnder, 2006; Prado et al., 2010; Ckırık 26 Yusufoğlu, 2025; AlBatati 26 AbuMostafa, 2024; Donnermeyer et al., 2019; Mohammadi et al., 2019; Rajda et al., 2021; Ravindran et al., 2024; Verdugo Balcázar 26 Carrillo Rengifo, 2025; Farias Silva et al., 2025; Rajda et al., 2021; Abo El Magd et al., 2022; Ravindran et al., 2024; Verdugo Balcázar 26 Carrillo Rengifo, 2025; Farias Silva et al., 2025; Ckırık 26 Yusufoğlu, 2025; Haichal et al., 2025; Orhan et al., 2025.
Acknowledgements
No financial or material support in this study. The study is entirely funded by the main researcher (Self-funding). This study will be registered on Nature. This is the first version of the protocol. Roles and responsibilities: Marina Mamdouh Kamal Antonyous - main researcher, data enterer, and research writer. Prof. Dr. Alaa Abdelsalam Elbaz - Monitoring and editing the data, and the entire process of the study. Access the final results and data collected from the study. Dr. Ghada Ihab ElWazan - Monitor the process of data collection. Generate a random sequence of the sample and undergo proper allocation concealment, implantation. Access to the final data.