Retreatment Techniques Research Articles

Comparison of Retreatability of AH Plus Sealer and Bioceramic Sealer with Solvent, Retreatment Files and Diode Laser: A CBCT and SEM Analysis

ABSTRACT Aim: The present study evaluated the retreatability of canals obturated using AH Plus sealer and Bioceramic (BC) sealers, employing Cone beam computed tomography (CBCT) and Scanning Electron Microscope (SEM). Methodology: A group of 90 extracted premolars was classified into two main categories based on whether they were sealed with AH Plus or BC Sealer. Each of these categories was then divided into two subcategories according to the retreatment technique applied. CBCT and SEM were used to assess the residual filling material within the canals. Results: The findings showed that there was no marked statistical variation in the retreatment success of canals sealed with BC and AH Plus sealers. Conclusion: The diode laser was the most effective modality for eliminating root canal filling materials in the least amount of time. None of the retreatment modalities used removed the obturating material completely.

Orthodontic re-treatment of class II malocclusion – Strategies for correction of anchorage loss

Orthodontic re-treatment may be required in cases of sub-optimal treatment outcomes. These outcomes may often be due to appliance-driven treatment plan, inadequate bio-mechanical considerations during treatment or poor operator skills. Common issues include anchorage loss, deepening of bite, incorrect extraction protocols, re-opened extraction spaces and loss of vertical control. To address these problems, traditional orthodontic appliances, skeletal anchorage systems, customized appliances, and clear aligners may offer a ray of hope, provided they are used judiciously. To effectively manage re-treatment techniques, it's important to have a solid understanding of the anatomic limits, biomechanics, and potential side effects. Proper case selection is extremely crucial for overall clinical success in such complex situations. Therefore, establishing guidelines and understanding the biomechanical perspectives of various appliance systems are essential to address these challenges in modern orthodontic practice.

Laser-assisted Root Canal Filling Removal of Lower Incisors - A Micro-CT Study.

To compare the efficiency of root canal filling removal from oval-shaped root canals with high-energy Er:YAG laser and additional instrumentation with a rotary Ni-Ti XP-Endo Finisher R system. The in vitro study was accomplished on 12 freshly extracted single-rooted mandibular incisors with one straight oval-shaped root canal, shaped with XP-Endo Shaper 30/.04 and obturated by using the warm vertical condensation technique subjected to further endodontic orthograde retreatment. Group 1: the first retreatment was carried out using a high-energy Er:YAG laser (n = 12). Group 2: the additional retreatment of the same specimens was performed with the XP-Endo Finisher-R system (n = 12). The effectiveness of the retreatment techniques was evaluated by a threefold micro-CT examination. The amount of the remaining root canal filling material was analyzed by Mann-Whitney U test and Friedman tests. A significant decrease in the quantity of the root canal filling was found following the first and after the second retreatment, compared to the initial values in all examined sections (P < 0.001). Within groups, additional application of the Ni-Ti system resulted in no significant removal of the filling materials (P > 0.05). None of the systems resulted in complete root canal filling removal. Despite the improved results after the application of the supplementary retreatment protocol, none of the root canal walls were completely clean in the apical area. The high-energy Er:YAG laser and XP-Endo Finisher R rotary system can be successfully used in endodontic orthograde retreatment under relevant operating parameters.

Factors Influencing the Success of Endodontic Retreatment: Insights from a Retrospective Study.

The purpose of this retrospective study was to assess the variables affecting endodontic retreatment technique success. A 5-year period of 500 patient records from a dental clinic were examined. Pre-operative factors, procedure specifics, post-operative results, and demographic information were all documented. The study employed statistical analysis to determine the important factors that influence retreatment success. The average age of the study group was 45.2 years, and 56% of the participants were female. Sixty-four percent of patients had multiple root canals, and the most frequent initial diagnosis (60%) was apical periodontitis. The results of the surgery varied: 50% of patients had full healing, 30% had partial healing, and 20% had no improvement at all. Significant indicators of retreatment success were found to include age, initial diagnosis, and root canal morphology (P < 0.05). The effectiveness of endodontic retreatment operations is mostly influenced by age, apical periodontitis, and root canal morphology. Optimizing treatment results requires individualized treatment techniques based on each patient's unique features. Clinicians can benefit greatly from these findings in terms of increasing endodontic retreatment success rates and enhancing patient care.

Extrusion of debris during retreatment using various nickel-titanium files in teeth with simulated lateral root perforation.

To investigate the influence of various nickel-titanium (Ni-Ti) files on debris extrusion during the retreatment of teeth with simulated lateral root perforation, focusing on root resorption. Sixty human mandibular premolar teeth were divided into groups with and without perforation and further subdivided based on the retreatment technique. Lateral root perforations were created in one group (Group 1), while the other group had no perforations (Group 2). Two retreatment techniques were compared: Remover (RE)+One RECI (OR) and ProTaper Universal Retreatment (PTUR)+WaveOne Gold (WOG). The weight of the extruded debris was determined. The time of both retreatment procedures was measured. Statistical analyses were performed using a two-way analysis of variance (ANOVA) test (P < 0.05). Teeth with simulated lateral root perforation exhibited higher extrusion of debris during retreatment. In both groups, RE+OR files led to more extruded debris than PTUR+WOG files. However, this difference was statistically significant in Group 2 (P < 0.001). Compared to PTUR+WOG files, RE+OR files showed a statistically significant longer time to remove obturation material (P < 0.001). Perforated teeth exhibited significantly higher debris extrusion. While both file systems demonstrated similar debris extrusion in perforated teeth, the RE+OR files significantly increased debris extrusion in non-perforated teeth compared to the PTUR+WOG files.

Endodontic retreatment of premolar with an impediment

Background: Root canal treatment can fail due to several causes. One of them is root canal calcifications. Purpose: To explain root canal retreatment technique in premolar with calcification. Case(s): A 65 years old female patient came to universitas airlangga dental hospital with a chief complaint of pain on tooth number 34 and 35. Tooth number 34 and 35 had an old restoration with secondary caries. Both teeth did not respond to vitality test. Both teeth were tender on percussion and bite test. Surrounding soft tissue was normal. Radiograph image reveals inadequate root canal obturations on both teeth and a periapical lesion on tooth 35. Case Management: Old restoration and root canal filling material was removed, then root canal retreatment was performed. Subsequently the tooth was restored with fiber post and zirconia crown. Discussion: old restoration has to be removed gently in order to prevent further damage to tooth structure. Root canal filling material can be removed with heated instruments, solvent, and rotary instruments. After root canal filling material removal, the remaining root canals need to be thoroughly shaped, cleaned, and sealed. Conclusion: root canal retreatment on premolar with an impediment can be successfully performed with appropriate instruments, materials, and technique.

Comparative Evaluation of Three Rotary Retreatment Systems for Apical Extrusion of Root Canals Obturated with Different Techniques

The aim of this study was to evaluate the quantitative amount of apically extruded debris after endodontic retreatment using three retreatment rotary systems D-RaCe, R-Endo, and EdgefileXR in the teeth obturated by two techniques (single cone and continuous wave compaction). Sixty human mandibular premolars with single straight root canals were prepared by 2Shape endodontic rotary system with file size (25/0.04). After that, samples were divided into two groups according to the technique of obturation used (n=30/group): A: single cone and B: continuous wave compaction. Then, further random subdivision for each group into three sub groups according to the system used for retreatment (n=10/group) as follow: A1,B1:D-RaCe, A2,B2:R-Endo, and A3,B3: EdgefileXR. Preweighed Eppendorf tubes were used to collect the apical extruded material during endodontic retreatment. Then, Eppendorf tubes were stored in an incubator at 68C for 5 days. The weight of extruded debris was calculated by subtracting the weight of the empty tube from the weight of the tube containing the extruded debris. Data were analyzed statistically using one way ANOVA analysis of variance and post hoc Duncan test. EdgeFileXR and R-Endo were significantly not different, but significantly different from D-race in two obturation technique. Also, result showed that the same system exhibited no difference in both obturation techniques. All retreatment techniques resulted in apical extrusion debris. Also, it was concluded that the techniques of obturation had no significant effect in the amount of apical extruded debris by different retreatment systems used in this study.

Evaluation of the efficacy of rotary and reciprocating systems for the removal of filling material for various root canal filling techniques.

This study aimed to evaluate the efficacy of various filling and retreatment techniques for oval-shaped root canals. Sixty distal roots of mandibular molar teeth were included in the study. The roots were prepared using the ProTaper Next (PTN) X4 rotary system and irrigation with 2.5% NaOCl. The roots were then divided into three groups and filled with Total Fill BC Sealer (FKG Dentaire) using three different techniques (n=20): single cone (SC), GuttaCore (GC), and warm vertical condensation (WVC). The retreatment procedure was performed using two different instrumentation techniques: Reciproc 50 (R50) and PTN X5 (n=10). To analyze the remaining filling material, the roots were divided buccolingually in two parts with the help of diamond separators, and photographs were taken at x16 magnification using a dental operating microscope (DOM). The ratio of the remaining filling materials was calculated using image analysis software and statistically evaluated using the Kruskal-Wallis test. None of the assessed retreatment procedures completely removed the filling materials from the root canals. For both instrumentation techniques, more root canal filling material remained in the WVC group (P<0.05). The GC filling technique had a higher cleaning percentage than the WVC and SC techniques in the coronal region. The R50 system was found to be superior to the PTN X5 system for retreatment, and the root canal fillings applied using the WVC technique were more difficult to remove than the fillings applied using the other techniques.

Effect of different retreatment files using different kinematics on the release of inflammatory mediators in root canal retreatment of single-rooted teeth: a randomized clinical trial.

This randomized clinical trial aimed to evaluate the effect of two rotaries (ProTaper Universal Retreatment (PTUR)), D-Race (DR) + XP-Endo Finisher R (XPFR) and one reciprocating (Reciproc Blue (RB) retreatment techniques on the release of neuropeptides (Substance P, calcitonin gene-related peptide (CGRP)), and cytokines (IL-6 and IL-10) in periapical fluid in root canal retreatment of single-rooted teeth. In this randomized clinical trial (ClinicalTrials.gov ID: NCT05039502), seventy-five patients scheduled for retreatment were randomly divided into 3 groups according to the file system used to remove root canal filling materials (n = 25): PTUR, RB, and DR + XPFR. After reshaping and disinfection of the root canals, periapical fluid samples were taken, and the levels of Substance P, CGRP, IL-6, and IL-10 were measured by enzyme-linked immunosorbent assay (ELISA) test. Data were analyzed using the Kruskal-Wallis and chi-square tests. The level of significance was set as p = 0. 05. All the allocated participants received the intervention and were analyzed. There was no statistically significant difference among groups in terms of gender, age, tooth localization, and the distribution of analgesic use after treatment (p values 0.799, 0.095, 0.637, 1.000, respectively). No statistically significant difference was found in terms of the levels of Substance P, CGRP, and IL-10 among groups (p > .05), except IL-6. PTUR, RB, and DR + XPFR files have comparable results in the expression of inflammatory mediators. Retreatment files powered with rotary or reciprocating motion produced similar neuropeptide and cytokine levels in patients.

Retreatment of Oval-Shaped Root Canals – Difficulties and Treatment Approaches

The complex anatomy of oval-shaped root canals presents a major challenge for secondary endodontic retreatment. The positive outcome of the retreatment depends on the proper cleaning and reshaping of the root canal space. Despite the use of various retreatment techniques and the improvement of additional protocols, none of them has yet succeeded in cleaning the entire root canal from filling residue. The untouched irregularities of the oval-shaped canals represent a reservoir for debris and microorganisms that are the main cause of endodontic treatment failure or delayed healing process. Further research should be done to improve the retreatment protocols of oval shaped canals. The aim of this review was to observe the articles investigating the efficacy for retreatment of oval-shaped root canals in the last 10 years.

Microcomputed tomographic analysis of the efficiency of two retreatment techniques in removing root canal filling materials from mandibular incisors

This study aimed to evaluate the removal effect of the ProTaper Next system (PTN) combined with manual nickel-titanium Hedström (MNiTiH) files or chloroform on filling materials of mandibular incisors by microcomputed tomography (micro-CT). Sixty-four extracted human mandibular incisors were finally selected and assigned to two groups (n = 32) based on root canal morphology after instrumentation. Two subgroups (n = 16) were formed based on two retreatment methods. The volume of residual filling materials (RFMs) and the surface area covered by RFMs were analyzed by micro-CT, the apical extrusion and the time taken for removing the filling materials were recorded. A smaller percentage of the volume of RFMs and less surface area covered by RFMs occurred in PTN combined with MNiTiH groups and round-shaped canal incisors (P < 0.05). The time taken for removing the filling materials was not significantly different in all groups (P > 0.05). The apical extrusion was significantly less in PTN combined with MNiTiH groups than in PTN combined with chloroform groups (P < 0.05). Neither of the two methods rendered root canals completely free from filling materials. PTN combined with MNiTiH could reduce the apical extrusion and remove filling materials more efficiently than PTN combined with chloroform.

Effectiveness of Retreatment of Oval-Shaped Canals Filled With Warm Gutta-Percha: A Systematic Review

Oval-shaped canals with their isthmuses and inter-canal communications represent a challenge for secondary endodontic treatment. Different techniques have been proposed to enhance the filling removal during retreatment procedures of oval canals filled with warm gutta-percha techniques. The aim of this review article is to systematically summarize and analyze published in vitro studies over a ten-year period of time (2012-2022), evaluating the effectiveness of retreatment of oval-shaped canals filled with warm vertical compaction technique and/or carrier-based gutta-percha. A thorough search in PubMed - MEDLINE, The Cochrane Library and Science Direct databases and manual web search was performed. After the investigations were assessed by two reviewers. A total number of eleven articles out of 145 titles covered all eligibility criteria and were selected for further synthesis. All articles investigated the effectiveness of retreatment techniques in oval-shaped root canals filled with warm vertical compaction or/and carrier-based gutta-percha. According to the present review none of the currently described retreatment techniques resulted in completely clean of remnants root canal walls. Secondary endodontic treatment is still a difficult procedure and due to the complex anatomy of oval-shaped root canals, their retreatment represents even a bigger challenge and often requires additional cleaning procedures.

Micro-CT evaluation of the removal of root fillings using rotary and reciprocating systems supplemented by XP-Endo Finisher, the Self-Adjusting File, or Er,Cr:YSGG laser.

This study aimed to compare the effectiveness of a single-file reciprocating system (WaveOne Gold, WOG) and a multi-file rotary system (ProTaper Universal Retreatment, PTUR) in removing canal filling from severely curved canals and to evaluate the possible adjunctive effects of XP-Endo Finisher (XPF), the Self-Adjusting File (SAF), and an erbium, chromium: yttrium, scandium, gallium garnet (Er,Cr:YSGG) laser using micro-computed tomography (μCT). Sixty-six curved mandibular molars were divided into 2 groups based on the retreatment technique and then into 3 based on the supplementary method. The residual filling volumes and root canals were evaluated with μCT before and after retreatment, and after the supplementary steps. The data were statistically analyzed with the t-test, Mann-Whitney U test, analysis of covariance, and factorial analysis of variance (p < 0.05). PTUR and WOG showed no significant difference in removing filling materials (p > 0.05). The supplementary techniques were significantly more effective than reciprocating or rotary systems only (p < 0.01). The supplementary steps showed no significant differences in canal filling removal effectiveness (p > 0.05), but XPF showed less dentin reduction than the SAF and Er,Cr:YSGG laser (p < 0.01). The supplementary methods significantly decreased the volume of residual filling materials. XPF caused minimal changes in root canal volume and might be preferred for retreatment in curved root canals. Supplementary approaches after retreatment procedures may improve root canal cleanliness.

The Effect of Number of Visits, Use of Solvent and Gutta-percha Removal Technique on Postoperative Pain following Nonsurgical Endodontic Retreatment; A Systematic Review and Meta-analysis.

The nonsurgical endodontic retreatment (NERT) is the first choice of dental ministration when primary/initial endodontic treatment fails. The present study aimed to investigate the presence of postoperative pain (POP) after NERT in permanent asymptomatic teeth as well as possible factors associated with POP. A comprehensive search of literature was performed in Pubmed/MEDLINE, Embase, Scopus and Web of Science databases, up to January 2023; including randomized clinical trials and prospective studies. The risk of bias was assessed with RoB 2.0 and ROBINS-I tools. Subgroups analyses were conducted to evaluate the differences in the incidence or level of POP between the number of visits, the use/not use of solvent, the removal technique of gutta-percha, and the period of POP analysis. Mean differences and confidence intervals (CI) of 95% were used as measures of effect, and meta-regression was used along with subgroup analysis. The certainty of evidence was assessed using GRADE, and the probability value of <0.05 was considered significant. Twenty-four studies were selected, with thirteen included in the meta-analysis. There was a statistical difference between the incidence of POP after 24 h (95% CI, 0.28 to 0.52) and one week (95% CI, 0.02 to 0.13) from the endodontic retreatment (P<0.01). However, there was no statistical difference between different techniques, number of visits and use of solvent (P>0.05) in the same period. In addition, the certainty of evidence was very low. Post-operative pain is a common response to NERT, independent of the retreatment technique(s) applied, number of visits and use of solvent(s); with very low certainty of evidence as well as low risk of bias. Moreover, the current analysis showed a (very) serious risk of inconsistency and imprecision. However, POP was significantly reduced within 1 week of the NERT.

Evaluation of Dentinal Microcracks following Diode Laser- and Ultrasonic-Activated Removal of Bioceramic Material during Root Canal Retreatment.

This study is aimed at evaluating the use of microcomputed tomography (micro-CT) analysis and the dentinal microcrack formation following retreatment of bioceramic sealer employing adjunct laser-activated irrigation and ultrasonic-activated irrigation. Thirty sound human single-canal teeth (n = 30) obturated using the single-cone technique with bioceramic sealer were retreated using nickel-titanium (NiTi) rotary files. The sample was randomly divided into three equal groups: group 1, the control group, was not subjected to further treatment; group 2 underwent ultrasonic activation of irrigants; group 3 underwent active irrigation with a diode laser (980 nm wavelength). Using micro-CT, the teeth were scanned before and after retreatment protocols. Two calibrated experienced observers viewed the cross-sectional images and calculated the number of dentinal defects. The presence of any crack or craze line on the external root surface or internal canal wall was counted. Data were analyzed using Friedman's two-way analysis of variance and Fisher's exact test. Statistical significance was set at p < 0.05. A significant increase occurred in the number of cracks post retreatment protocols, specifically in the coronal and middle canal thirds, compared to pre- and postinstrumentation (p = 0.0001). However, ultrasonic- or laser-activated irrigation did not result in a significant increase in the number of cracks (p = 0.345). NiTi rotary root canal retreatment was associated with a significant increase in dentinal microcracks. However, employing ultrasonic- or laser-activated irrigation as adjunct retreatment techniques did not reveal a significant increase in dentinal microcracks within the roots.

Comparison of the Time Required by Six Different Retreatment Techniques for Retrieval of Gutta-Percha: An In Vitro Study

Abstract Objective A retreatment is a conservative approach than periapical surgery in case of failed root canal treatment. Retreatment techniques that are efficient and faster should be the main concern to treat endodontic failure. This study aimed to compare the time required by various hand and rotary retreatment systems for the retrieval of gutta-percha (GP) from root canals. Materials and Methods A total of 120 extracted single-rooted premolar teeth with straight canals were chosen. Biomechanical preparation was completed using the Step-Back approach keeping the master apical file size 35. Then, teeth were down-packed and back-filled with System B device, along with AH Plus sealer. The teeth were categorized into six groups (n = 20) at random as per techniques applied for retrieval of GP: group I hand instrumentation (Hedstrom files and Gates-Glidden drills); group II ProTaper Universal Retreatment (PTUR) system; group III Mtwo Retreatment (Mtwo R) system; group IV D-RaCe; group V R-Endo; and group VI Mani Gutta Percha Remover (NRT-GPR). A chronometer was used to measure the time required for retrieval of GP. Data were examined by comparative evaluation of one-way analysis of variance and chi-square test. Results Among all the retreatment techniques used, D-RaCe was faster in GP retrieval than other groups. NRT-GPR system also took less time than other groups except for the D-RaCe system. The Mtwo R system was the slowest among all groups. Conclusion D-RaCe retreatment instruments required extensively less time for retrieval of GP than other groups (p &lt; 0.001).

Efficiency of diode laser and ultrasonic-activated irrigation in retreatment of gutta percha and bioceramic sealer: An in vitro study.

This study was to determine the effectiveness of diode laser (LI) and ultrasonic (UI)-activated irrigation with or without a surfactant as adjunct techniques during the retreatment of gutta-percha and tricalcium silicate-based sealer (BC) sealer. Forty-two single-rooted premolars were instrumented and filled with gutta-percha and BC sealer, then retreated using NiTi retreatment rotary files. Teeth were randomly divided into three equal groups: Control (manual irrigation), UI and LI groups. Each group was subdivided into 2.5% NaOCl irrigant and ChlorCid™️ Surf subgroups. The amount of material removed following UI and LI was significantly greater than that of manual irrigation (p < 0.0001). However, there was no significant difference between the surfactant subgroups, irrespective of irrigation technique (p=1.00, p=0.535, p=0.805). The use of UI and LI adjuncts to NiTi rotary retreatment techniques showed significant improvement in gutta-percha with BC sealer removal. However, surfactants had no effect on the efficacy.

Effectiveness of the REvision System and Sonic Irrigation in the Removal of Root Canal Filling Material from Oval Canals: An In Vitro Study.

This study aimed to evaluate the effectiveness of the Endostar REvision system (Poldent, Warsaw, Poland) in the removal of filling materials from oval root canals using sonic irrigation as an additional cleaning method. Thirty human-extracted mandibular premolars with oval canals were prepared using the ProTaper Universal system (Dentsply Maillefer, Ballaigues, Switzerland) up to instrument F1 (20/.07), and then filled by the continuous wave vertical compaction technique using pulp canal sealer EWT (Sybron Dental Specialties, Orange, CA, USA). The teeth were randomly divided into two groups (n = 15) according to the instrumentation system and the additional cleaning method, as follows: REvision (30/.08, 25/.06) with EQ-S sonic activation (Meta Biomed, Chungcheongbuk-do, Korea), REvision (30/.08, 25/.06) without additional activation. All specimens were sectioned longitudinally at 3 and 7 mm from the apex, and analyzed using digital microscopy (KEYENCE, Osaka, Japan) to measure the total area of the residual obturation materials, followed by SEM analysis. The data on the percentage of remaining filling material were analyzed by Kruskal–Wallis one-way Analysis of Variance on ranks. None of the retreatment protocols completely removed the filling material from the root canals (p > 0.05); the retreatment technique using sonic activation showed statistically less residual filling materials than the retreatment technique using irrigants without activation at the coronal third (p < 0.05), whilst no significant difference was found between both tested groups at the apical and middle thirds (p > 0.05). The REvision system showed promising results in the removal of filling materials from oval canals.

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

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

Efficacy of Rotary Retreatment Techniques Assisted with Passive Ultrasonic Activation of Resin Solvent in Removal of Gutta-percha with Epoxy Resin and MTA Based Root Canal Sealers: An In-vitro Study

Introduction: Endodontic retreatment is indicated in cases of failed primary endodontic treatment. The main goal of retreatment is to establish conditions that will enable the healing of the periapical tissue. Aim: To evaluate the efficacy of rotary retreatment with the ProTaper Universal Retreatment system supplemented with passive ultrasonic activation of solvent in retreatment of singlerooted mandibular premolar teeth obturated with gutta-percha and two different root canal sealers (AH Plus and MTA Fillapex). Materials and Methods: This in-vitro study was conducted in the Department of Conservative Dentistry and Endodontics at Mahatma Gandhi Mission’s Dental College and Hospital, Navi Mumbai, Maharashtra, India, from January 2019 to April 2019. Total 66 freshly extracted human single rooted mandibular premolars were used in this study. Root canal preparation was done using ProTaper Next rotary files. Teeth were decoronated to get a uniform length of 18 mm and were divided into three retreatment groups based on the technique used for retreatment. Group I included rotary retreatment, Group II involved rotary retreatment with solvent and paper point wicking, and Group III involved rotary retreatment with passive ultrasonic activation of solvent and paper point wicking. Based on the sealer used for obturation, teeth in each group were further divided into two subgroups, subgroup A with AH Plus sealer and subgroup B with MTA Fillapex sealer. Teeth were stored in an incubator for 30 days to allow sealer to set after which sectioning of the specimens was done buccolingually for examination under the stereomicroscope and photographed. Statistical analysis was done by using parametric Analysis of Variance (ANOVA) followed by Post-hoc tests and Unpaired t-test. Results: No statistically significant difference in percentage area of residual root canal filling material noted between the group I and II and when obturated with gutta-percha and AH Plus sealer (subgroup A) as p-value=0.215. Whereas, it revealed a statistically significant difference between the group I, II, and III when obturated with gutta-percha and MTA Fillapex sealer (subgroup B) as p-value&lt;0.001. Conclusion: Passive ultrasonic activation of solvent after guttapercha removal using ProTaper Universal rotary files could improve the quality of endodontic retreatment.