Nonsurgical Retreatment Research Articles

Root-end Surgery or Nonsurgical Retreatment: Are There Differences in Long-term Outcome?

IntroductionThe decision of which modality of secondary endodontic treatment to perform is multifactorial and clinician dependent. The literature surrounding the long-term survival of nonsurgical retreatment compared with surgical retreatment remains equivocal and warrants further investigation. This 7-year retrospective study seeks to compare the outcome of nonsurgical retreatments with that of root-end surgeries performed on teeth without prior nonsurgical retreatments. MethodsInsurance claims from 1021 teeth of 987 patients in the Delta Dental of Wisconsin database were analyzed from the years 2008–2017. Tooth survival was evaluated using Cox regression models, and the P value was set at .05. Survival time was considered from the time of completion of nonsurgical retreatment or root-end surgery to the time of an untoward event, which was defined as extraction after root-end surgery or extraction/root-end surgery after nonsurgical retreatment. Only procedures performed by endodontists were included in the analysis. ResultsThe survival rate of teeth that received nonsurgical retreatment was 90% after 2 years, 86.8% after 4 years, and 85% after 6 years. The survival rate of teeth that received root-end surgery was 93.7% after 2 years, 90.5% after 4 years, and 88% after 6 years. No statistically significant difference was found in the survival of nonsurgical retreatment compared with root-end surgery. Likewise, no statistically significant difference was found within or between tooth types (anterior, premolar, or molar) when comparing nonsurgical retreatment with root-end surgery. ConclusionsThe results of this study indicate that clinicians can choose either nonsurgical retreatment or root-end surgery after failed primary root canal therapy. Tooth location was not a determining factor in the survival rate after nonsurgical retreatment or root-end surgery.

Nonsurgical Treatment Outcomes and Prognostic Factors for Cases with Lesions of Endodontic Origin in a Private Practice

Aim: The prognosis of the healing of an apical lesion is extremely important for the treatment decision for tooth retention or implantation. In several studies, the presence of an apical lesion was shown to be a significant factor in both primary treatment and non-surgical retreatment. The aim of the present study was the retrospective investigation of the prognosis of the healing of bony apical lesions of teeth, which were treated endodontically. The evaluation contained various clinical parameters that can influence the success of the root canal treatment. Materials and Method: 62 teeth were treated in 52 patients during the study period. The treatment was carried out by a specialist in endodontics with the aid of the dental surgical microscope and a two-stage procedure. Two certified examiners assessed the radiological results after three to 72 months. Preoperative and postoperative information related to potential prognostic factors was evaluated. Results: Results of the 62 apical lesions, 82.3% (examiner 1) - 88.75% (examiner 2) were classified as healed. Of all the prognostic factors analyzed, none showed a significant influence on the treatment success. The success rate of the present study was in the range of comparable studies. Conclusions: The apical lesion can be treated with relatively high success rates if general micro-endodontic procedures are followed.

Adjunctive procedure with solvent mixtures in non-surgical endodontic retreatment: does it affect root dentin hardness?

The aim of this study was to compare the effects of new irrigation solvent mixtures with Methyl ethyl ketone (MEK)/Tetrachloroethylene (TCE) and MEK/Orange oil (OOil), and different agitation techniques on dentin hardness. One hundred forty-four mandibular teeth were prepared and standardized, with each root's middle part transversely sectioned. Initial hardness was measured using a Vickers microhardness tester. Specimens were divided into four groups of agitation techniques (n = 36): no agitation; EndoActivator; IrriSafe; and XP-endo Finisher R. Each group was subdivided into six subgroups of irrigation protocols (n = 6): saline solution; NaOCl + EDTA; NaOCl + EDTA + MEK/TCE; MEK/TCE; NaOCl + EDTA + MEK/OOil; MEK/OOil. Final hardness was measured. The irrigation protocols NaOCl + EDTA, NaOCl + EDTA + MEK/TCE, and NaOCl + EDTA + MEK/OOil significantly decreased dentin hardness, while MEK/OOil increased it (p < 0.05). Comparing to NaOCl + EDTA sequence, dentin hardness increased significantly with the additional exposure to MEK/TCE (3%NaOCl + 17%EDTA + MEK/TCE) or MEK/OOil (3%NaOCl + 17%EDTA + MEK/OOil) (p < 0.05). There were no significant differences regarding agitation effects on dentin hardness decrease. The irrigation protocols affected dentin hardness significantly. However, the additional solvent proposals do not seem to address further concerns on dentin's mechanical properties. Agitation did not show any influence on dentin's hardness reduction.

Outcomes and prognostic factors of apical periodontitis by root canal treatment and endodontic microsurgery-a retrospective cohort study.

The aim of this study was to analyze the outcome and prognostic factors of root canal treatment (RCT) and endodontic microsurgery (EMS) in the treatment of apical periodontitis (AP), respectively, and to compare the outcome and prognostic factors between initial RCT and nonsurgical retreatment (re-RCT) for AP. Patients with AP were recruited from the Stomatology Department of Peking University Third Hospital from January 2016 to December 2019. Data were collected by medical records review. Univariate analysis of treatment outcome was performed for the total RCT group, initial RCT group, re-RCT group and EMS group, respectively. Multivariate logistic regression was performed for the three RCT groups, respectively, but not for the EMS group. The overall success of treatment for AP was 73.8%. The success rate of RCT in 229 cases was 70.7%, while that of EMS in 34 cases was 94.1%. The failure of RCT was significantly higher for elderly patients [odds ratio (OR) =1.025, P=0.013], teeth with incomplete fracture (OR =7.082, P=0.013), teeth with a greater crown root ratio (OR =1.198, P=0.029), teeth treated by a general dentist (OR =2.16, P=0.042) and teeth with unqualified treatment (OR =2.841, P=0.002). Of the 166 teeth treated by initial RCT, the success was 68.1%. A greater crown root ratio (OR =1.333, P=0.004) was identified as a risk factor for treatment. Of the 63 teeth treated by re-RCT, the success was 77.8%. A lower success was observed in teeth with unqualified treatment (OR =5.291, P=0.018). With regard to EMS, the univariate analysis showed that none of the variables were significantly related to the outcome. For AP treated by RCT, age, incomplete tooth fracture, crown root ratio, doctor classification and unqualified treatment had a strong impact on determining outcome. For initial RCT, crown root ratio was a significant outcome predictor, while for re-RCT, unqualified treatment was a strong statistically significant factor. No significant difference was found between the success of initial RCT and re-RCT for AP.

The Efficacy of Reciproc Blue® For Canal Cleanliness Following the Retreatment of Maxillary First Molar: In Vitro Analysis

Nonsurgical retreatment involves removing mechanical barriers such as gutta-percha to achieve proper cleaning and disinfection. The complexity of the anatomy of molar tooth gives challenge in retreatment procedure. Thus, this study evaluates the amount of residual gutta-percha after retreatment with rotary files (Reciproc Blue®) from each maxillary first molar canal using cone-beam computed tomography (CBCT) and the time required to accomplish it. Nine freshly extracted maxillary molars were instrumented and obturated. Preoperative CBCT was taken, and retreatment was done using Reciproc Blue®. CBCT was taken post retreatment, and the residual volume percentage of gutta-percha from each canal was calculated. The total retreatment time was recorded, and the data were statistically analyzed. The result shows no statistically significant difference in the amount of residual filling material in mesiobuccal, distobuccal, and palatal canal for maxillary first molar and total time used for retreatment with Reciproc Blue® system.

Efficacy of Removing Thermafil and GuttaCore from Straight Root Canal Systems Using a Novel Non-Surgical Root Canal Re-Treatment System: A Micro-Computed Tomography Analysis.

The present study aims to evaluate the effectiveness of an XP-endo non-surgical root canal re-treatment system in removing both GuttaCore and Thermafil gutta-percha carrier-based root canal filling materials from straight root canal systems using micro-computed tomography (micro-CT) analysis. The study was performed on 20 single-rooted upper teeth, which were randomly allocated into the following study groups: Group A, Thermafil and AH Plus sealer (n = 10); Group B, GuttaCore and AH Plus sealer (n = 10). Before and after the non-surgical root canal re-treatment procedure, the samples were submitted for a micro-CT analysis. The volume of the root canal filling material (mm3), the volume of the remaining root canal filling material (mm3) and the time (minutes) needed to remove the root canal filling material were also recorded. Student’s t-test was used to analyze the results. No statistically significant differences were found between the volume of the remaining root canal filling material in the GuttaCore and Thermafil root canal filling systems at the coronal third (p = 0.782), middle third (p = 0.838) or apical third (p = 0.882) of the straight root canal systems; however, the GuttaCore required a statistically significant (p = 0.037) shorter amount of time (4.72 ± 0.76 min) to be removed than the Thermafil carrier-based root canal filling material (5.92 ± 1.42 min). The XP-endo Finisher non-surgical endodontic re-treatment system removes both GuttaCore and Thermafil gutta-percha carrier-based root canal filling materials from straight root canal systems, although removal of the GuttaCore gutta-percha carrier-based root canal filling material required less time.

Flapless application of enamel matrix derivative in periodontal retreatment: A multicentre randomized feasibility trial

To investigate the potential benefit of enamel matrix derivative (EMD) as adjunct to re-instrumentation of residual pockets persisting after steps 1 and 2 of periodontal therapy. 44 adult patients participated in a multicentre feasibility randomized clinical trial with split-mouth design. They had presented at re-evaluation after initial non-surgical periodontal therapy (steps 1 and 2 of periodontal therapy) for generalized periodontitis with at least 2 teeth with residual probing pocket depths (PPD) ≥5 and ≤8mm, with bleeding on probing (BOP). Two teeth with similar PPD were randomized to receive re-instrumentation either with (test) or without (control) adjunctive flapless administration of EMD. Differences in the changes of PPD and BOP from baseline to 6 and 12months were analysed, and the frequencies of pocket closure (PPD ≤4mm and no BOP) compared. For the primary outcome "change of mean PPD after 6months," a significant additional benefit of 0.79±1.3mm (p<.0001) could be observed for the test group. At 12months, this difference could be maintained (0.85±1.1mm; p<.0001). The frequency of pocket closure in the test group was 69% at 6 and 80% at 12months and significantly higher than in the control group with 34% and 42%, respectively (p<.01). The results of the present feasibility study indicate a benefit of adjunctive EMD during non-surgical retreatment (step 3 of periodontal therapy) of residual deep pockets.

INTENTIONAL REPLANTATION- A VIABLE SOLUTION FOR INSTRUMENT SEPARATION: A CASE REPORT

The fracture of an endodontic instrument is an obstacle in the completion of successful endodontic therapy. Non-surgical re-treatment and surgical endodontics are not always viable solutions. The various methods of re-treatment for a separated instrument include le bypass, le retrieval or the surgical method of Apicoectomy. However, the mode of treatment also depends on the position of the separated instrument in the tooth, the anatomy of the tooth and also the root. In certain cases, le bypass or retrieval is not advocated. In such cases, other options for re-treatment are needed to be considered. Intentional replantation is a treatment option considered by many as a procedure of last resort when non-surgical and surgical endodontics is contraindicated. This procedure is often indicated where the separated instrument is at or beyond the apex. The case report discussed in this paper presentation demonstrates the procedure of intentional replantation as a viable solution where other retreatment procedures are not possible.

Does the Endodontic Education Level Affect Decision-Making for Endodontically Treated Teeth With Apical Periodontitis? A Web-Based Survey

ObjectivesThe management of endodontically treated teeth with apical periodontitis is debated among clinicians. The aim of this study was to evaluate treatment choices for endodontically treated teeth with different sizes of periapical lesions among endodontists, endodontics postgraduate students, general dental practitioners, and undergraduate students who had fulfilled their theoretical and clinical training in endodontics. Materials and MethodsPeriapical lesion images (no periapical lesion and 1-mm, 3-mm, and 5-mm periapical lesions) were formed on 4 different radiographs with a software program, and the survey included 16 radiographs that were emailed to 1881 participants. Treatment options included extraction, surgical or nonsurgical retreatment, and wait and see. The χ2 test was used to compare the responses of the participants. ResultsThe survey was returned by 1039 participants (55.23%). There were statistically significant differences among the responses of all participants for all cases (P < .05), except a case with a broken file and no lesion (P = .918). All participants decided to extract at an increased size from a 1-mm periapical lesion to a 5-mm periapical lesion. At all lesion sizes, general dental practitioners planned retreatment less when compared with other groups. ConclusionsThis survey study showed that there was a positive correlation between endodontic education level and retreatment decision-making. Dentists who confront seemingly hopeless endodontically treated teeth such as an instrument fracture, a missing canal, or a large periapical lesion should consult with an endodontist before making the decision to extract the tooth.

PERSISTENT APICAL PERIODONTITIS AFTER ENDODONTIC TREATMENT: SURGICAL MANAGEMENT

The high success of endodontic therapy for apical periodontitis treatment is well known. However, studies showed that between 20% to 60% of treated teeth in the population present with apical periodontitis after root canal therapy. When viable, non-surgical retreatment is the rst option while endodontic surgery should be the last resource for elimination of the disease. The aim of this case report is emphasize the potentiality of the successful outcome of surgical endodontic treatment following failed non-surgical treatment of a second maxillary premolar and rst maxillary molar

Type IIIb dens in dente endodontic retreatment: a case report

Dens in dente is a developmental anomaly characterized by dental tissues invagination that varies from a slight increase of the cingulum´s fossa to a deep groove that can extend up to the dental apex. Objectives The aim of this study was to report a dens in dente endodontic retreatment case with the presence of fistula and periapical lesion. Case report: Non-surgical retreatment was performed from the removal of the filling endodontic material, use of Calcium Hydroxide as intracanal medication changed every two months for a one year and a half period, and later, apical closure with MTA and endodontic filling of the remaining thirds with thermoplastic gutta-percha. Results: Postoperative follow-ups were performed for a 4 years period where a reduction of the periapical lesion diameter and disappearance of the fistula were observed. Conclusion: These results demonstrate that the present non-surgical dens in dente endodontic retreatment protocol could be considered a viable option for success.

Multi-state outcome analysis of treatment interventions after failure of non-surgical root canal treatment: a 13-year retrospective study.

Objective To examine the factors affecting the transitions through treatment interventions after failure of non-surgical root canal treatment (NS-RCT).Methodology Insurance enrollment and claim information for enrollees of Delta Dental of Wisconsin (DDWI), USA were analyzed for 438,487 initial NS-RCT procedures to determine the effect of initial provider type and other covariates on additional treatments (no additional treatment, nonsurgical retreatment, surgical retreatment and extraction). A multi-state model was created using the “mstate” R package. Transitions between the four states identified by Code on Dental Procedures and Nomenclature were analyzed. Cox proportional Hazards regression stratified by transition type was used to estimate the effect of provider type on the risk of each transition, adjusting for covariates.Results The overall survival rates for all teeth that were treated by NS-RCT was 82.8% [95% CI 82.57%, 83.11%] at 10 years. Approximately, 7% of cases changed from the first state of initial NS-RCT during the 13-year study period with ultimately 0.9%, 0.4% and 5% of cases receiving non-surgical retreatment, surgical retreatment or extraction, respectively. Teeth are more likely to be retreated non-surgically than surgically, and to be extracted than retreated. In general, the probability of a tooth having non-surgical retreatment was higher if the initial provider was not an endodontist (Hazard Ratio (HR)=3.2). Molars were more likely to be non-surgically retreated (HR=2.0) or extracted (HR=2.8) when compared to anterior teeth. The probability of non-surgical retreatment (HR=0.93) or extraction (HR=0.50) was lower when a crown was placed within 90 days after NS-RCT.Conclusion Most teeth remained in the same state after treatment with no additional treatment transitions. When a transition occurred, it was more likely to be an extraction. Type of provider, age, location of the tooth, gender, and time to placement of final restoration significantly influence treatment transitions.

Using biodentine for non-surgical endodontic re-treatment of maxillary central incisor associated with severe external apical root: A case report with 2-years follow-up

A patient reported with pain and sinus opening in relation to a previously root canal treated maxillary central incisor. Intraoral radiograph revealed periapical radiolucency with shortening of root indicating external apical inflammatory root resorption associated with failed endodontic treatment. Nonsurgical re-treatment was started and intracanal calcium hydroxide (CaOH) was placed for four weeks. The tooth was obturated with Biodentine. At 6, 12, and 24 months follow-up, the patient was asymptomatic and radiograph revealed satisfactory healing. Inflammatory apical root resorption due to failed root canal treatment could compromise the root length and prognosis. Early arrest of such resorption is indicated by nonsurgical re-treatment using CaOH for root canal disinfection and obturating with bioactive material such as Biodentine, which results in the successful arrest of resorption and periapical healing.

Possible Causes for Failure of Endodontic Surgery - A Retrospective Series of 20 Resurgery Cases.

Objective:This study aimed to evaluate unsuccessful endodontic surgery cases for possible causes for treatment failure and evaluate if a nonsurgical retreatment (NSRTX) approach could have been a better alternative to resurgery.Methods:Analyses of clinical and cone-beam computed tomography (CBCT) images, periapical radiographs, and chart documentation determined study parameters. Preoperative factors were age, sex, tooth type, signs and/or symptoms, presence of periapical radiolucency, previous root canal treatment, timeline since previous endodontic surgery, presence of posts, cores, and restorations. The intra-operative factors were microsurgical classification, previous techniques, and current techniques utilized. Postoperative factors were signs and/or symptoms, time to follow-up, and healing status. The accessibility of the root canal system and the quality of the existing root filling were used to evaluate NSRTX as an alternative to resurgery.Results:A total of 1073 surgical cases from 2011-2019 were reviewed. In 14 patients, 20 cases matched the inclusion criteria and allowed for data extraction. The mean time since the previous surgery was 2.9±2.1 years, with a mean follow-up of 9.1±5.8 months after the resurgery. Possible reasons for failure identified were: insufficient root-end filling (leaking, off-axis preparation, lack of depth, overfill) n=12/20, 60.0%; missed anatomy (main and lateral canals, isthmus) n=9/20, 45.0%; incomplete resection n=6/20, 30.0%. In 18/20 cases (90.0%), resurgery appeared to be indicated for 2/20 cases (10.0%). Therefore, NSRTX may have been a potential alternative.Conclusion:Further evidence for possible causes of failure of endodontic surgery was provided, which were primarily iatrogenic. The evaluation of CBCT and high magnification intra-operative images proved beneficial for identifying critical issues for all investigated cases.

Characterization of the differential efficacy of austenitic vs martensitic NiTi rotary files in non-surgical root canal retreatment: a micro-CT analysis.

Aim: Our study aims to characterize the differential efficacy of martensitic and austenitic files in root canal retreatment regarding defiling ability, debris management and morphometric features. Materials and methods: A total of 10 human premolar teeth with two separate fully formed roots were selected, prepared with BioRace system (BR) up to a size BR2 (0.04/25). Root canals were filled and then divided according to the file type into two groups (n = 10). Two geometrically identical files have been used with the only difference between them is heat treatment; One Curve (OC) martensitic and One Shape (OS) austenitic. Preoperative and postoperative Micro-CT scans were done for all the samples, and the percent volume of residual filling materials was calculated. Canals reshaping and remaining debris in the canals were assessed by calculating the volume of the canals before and after retreatment using Micro-CT software. Results: The percentages of removed filling materials were similar between both groups (97.2% OC vs 97.8% OS). OS was significantly faster than OC (P < 0.05). Retreatment procedure did not significantly change volume, structure model index, surface area, and canal curvature. OS group transported the canals more than OC at the apical third (P < 0.05). There were no significant differences between both groups concerning un-instrumented surface area and accumulated hard tissue debris (AHTD) (P > 0.05). Conclusion: Under the circumstances of this study, neither file systems could completely remove the filling materials. However, OC resulted in less transportation than OS in the apical one third (P < 0.05). Also, OC resulted less AHTD than OS but with no statistical difference.

Non-Surgical Endodontic Retreatment of Anterior Tooth with a Large Periapical Lesion and Extruded Guta Percha with 36 Months Follow-Up: A Case Report

Root canal treatment failure depends on many factors. Overfillings, insufficient fillings, missing canals, failure to provide a complete apical plug, and impermeability of coronal restoration are some of them. Failed root canal treatment may not always manifest itself immediately after treatment. Sometimes, root canal treatments, which have not been done well, can manifest themselves with extensive lesions and severe pain in the apical after a long time. Apical resection may be considered as a solution in lesions that are too large to be treated, but retreatment without surgery should be attempted beforehand. Thus, the patient may have recovered from unnecessary surgical procedures and treated with a more conservative method. This case presents the non-surgical retreatment of a left lateral tooth with a large periapical lesion with extruded gutta percha followed by a 36-month follow-up.

Endodontic retreatment of a mandibular canine with two roots and two canals: a case report

Background: The knowledge of root canal anatomy is considered essential in the diagnoses and treatment of endodontic cases to assure successful outcomes. Although the mandibular canine is known to be a single- rooted tooth with a single canal, variations can be seen. However, the incidence of a mandibular canine having two roots and two canals is extremely rare. Case Presentation: This article reports a case of non-surgical retreatment of mandibular canine, with two roots and two canals, presented to the clinic with a periapical lesion. Chloroform and H-files were used to remove previous gutta percha, canals were shaped with a profile rotary system, and irrigated with 2.5% sodium hypochlorite. The canals were then obturated with gutta percha and AH Plus sealer. Conclusion: Clinicians must use all the available tools to help them detect anatomical variations to manage their cases successfully.

Root canal retreatment: a retrospective investigation using regression and data mining methods for the prediction of technical quality and periapical healing.

Objectives This study aimed to investigate patterns and risk factors related to the feasibility of achieving technical quality and periapical healing in root canal non-surgical retreatment, using regression and data mining methods.Methodology This retrospective observational study included 321 consecutive patients presenting for root canal retreatment. Patients were treated by graduate students, following standard protocols. Data on medical history, diagnosis, treatment, and follow-up visits variables were collected from physical records and periapical radiographs and transferred to an electronic chart database. Basic statistics were tabulated, and univariate and multivariate analytical methods were used to identify risk factors for technical quality and periapical healing. Decision trees were generated to predict technical quality and periapical healing patterns using the J48 algorithm in the Weka software.Results Technical outcome was satisfactory in 65.20%, and we observed periapical healing in 80.50% of the cases. Several factors were related to technical quality, including severity of root curvature and altered root canal morphology (p<0.05). Follow-up periods had a mean of 4.05 years. Periapical lesion area, tooth type, and apical resorption proved to be significantly associated with retreatment failure (p<0.05). Data mining analysis suggested that apical root resorption might prevent satisfactory technical outcomes even in teeth with straight root canals. Also, large periapical lesions and poor root filling quality in primary endodontic treatment might be related to healing failure.Conclusion Frequent patterns and factors affecting technical outcomes of endodontic retreatment included root canal morphological features and its alterations resulting from primary endodontic treatment. Healing outcomes were mainly associated with the extent of apical periodontitis pathological damages in dental and periapical tissues. To determine treatment predictability, we suggest patterns including clinical and radiographic features of apical periodontitis and technical quality of primary endodontic treatment.

Nonsurgical re-treatment of a twin-rooted maxillary lateral incisor

An accurate diagnosis of the anatomy of the root canal system is a prerequisite for successful endodontic treatment. Morphological variations or additional roots/root canal should always be expected. These variations should be strongly considered before starting any endodontic treatment using various diagnostic aids for better outcome therapy. Nonsurgical endodontic re-treatment of a painful twin-rooted maxillary lateral incisor tooth of a 40-year-old female was carried out due to improper diagnosis of the extra root. The clinical examination and radiographic analysis confirmed the diagnosis of previously treated/necrotic pulp and symptomatic apical periodontitis. The patient remained asymptomatic at 6-month follow-up both clinically and radiographically. The case report emphasized on the need for clinicians to be extra careful while treating such teeth and use of cone-beam computed tomography for their diagnosis and management.

Successful Retrieval of Metal Post and Nonsurgical Retreatment of Maxillary Canine Using Minimum Armamentarium

Removal of the different materials from the root canal in a failed endodontic treatment is a prime requisite for endodontic retreatment. Complete removal of the materials such as gutta percha, broken instruments, or post is of particular importance for accessing endodontic space, cleaning, shaping, and disinfection of the root canal. Intraradicular post removal poses a challenge to the clinician with associated risks. This case report focuses on removal of the metal post and endodontic retreatment of the maxillary canine with minimum armamentarium to enhance the longevity of the tooth.