Outcome of Endodontic Micro-resurgery: A Retrospective Study Based on Propensity Score–matched Survival Analysis

The outcome of combined use of iRoot BP Plus and iRoot SP for root-end filling in endodontic microsurgery: a randomized controlled trial

OBJECTIVES

Root-end filling is important for the clinical outcome of endodontic microsurgery. Our previous study showed that combined application of iRoot BP Plus Root Repair Material (BP-RRM) and iRoot SP Injectable Root Canal Sealer (SP-RCS) in root-end filling exhibited better apical sealing as compared to the application of BP-RRM alone. The aim of this randomized controlled clinical trial was to evaluate the effect of the combined use of BP-RRM and SP-RCS on the prognosis of teeth with refractory periapical diseases after endodontic microsurgery.

MATERIALS AND METHODS

240 teeth with refractory periapical diseases scheduled for endodontic microsurgery were randomly divided into BP-RRM/SP-RCS group (n = 120) and BP-RRM group (n = 120). The patients were followed up at 3 months, 6 months, and 12 months after endodontic microsurgery. Pre- and post-operative clinical and radiographic examinations were performed to evaluate the treatment outcome. The 1-year success rate of endodontic microsurgery in BP-RRM/SP-RCS and BP-RRM groups was compared by Chi-square test. Factors that might impact the prognosis were further analyzed using Chi-square test or Fisher's exact test.

RESULTS

A total of 221 teeth completed the 12-month follow-up. The 1-year success rates of the BP-RRM/SP-RCS and BP-RRM groups were 94.5% (104/110) and 92.8% (103/111), respectively. The combined use of BP-RRM and SP-RCS achieved a clinical outcome comparable to BP-RRM alone (P = 0.784). Tooth type (P = 0.002), through-and-through/apico-marginal lesion (P = 0.049), periodontal status (P < 0.0001), and Kim's lesion classification (P < 0.0001) were critical factors associated with the 1-year success of endodontic microsurgery.

CONCLUSIONS

The combined use of BP-RRM and SP-RCS is a practicable method for root-end filling in endodontic microsurgery with a satisfactory 1-year clinical outcome.

CLINICAL RELEVANCE

The combined application of BP-RRM and SP-RCS in EMS is an effective root-end filling method with a satisfactory 1-year clinical outcome.

TRIAL REGISTRATION

This study was registered in the Chinese Clinical Trial Registry (ChiCTR2100052174).

Cost-effectiveness analysis of full versus selective root canal retreatment

AIM

Selective root-canal retreatment has been proposed as an alternative to full retreatment in multirooted, root-canal-filled teeth with evidence of apical pathology, where only the affected root(s) is retreated. Whilst this option may save costs initially, failures and retreatments may compensate for these initial savings. We assessed the cost-effectiveness of full versus selective root-canal retreatment using data from a recent clinical pilot study, employing a modelling approach.

METHODOLOGY

A Markov model was constructed to follow up a previously root-canal treated maxillary molar with apical pathology on a single root (mesio-buccal), receiving either selective or full root-canal retreatment. A private-payer perspective in Dutch health care was adopted. Permanent molar teeth with apical lesions on the mesial root were simulated over the lifetime of initially 50-year-old patients. Teeth could have endodontic complications and require interventions such as retreatment or tooth extraction and replacement. Costs were calculated based on the Dutch dental fee catalogues. Monte-Carlo microsimulations were performed to assess lifetime costs and effectiveness (measured as tooth retention time), and the resulting cost-effectiveness. Probabilistic joint uncertainty and sensitivity analyses were performed, and cost-effectiveness at different willingness-to-pay-thresholds was evaluated.

RESULTS

In the base-case scenario, selective retreatment was less costly (2137; 2.5%-97.5% percentiles: 1944-2340 Euro) and more effective (19.6; 18.3-20.8 Years) than full retreatment (2495; 2305-2671 Euro; 16.5; 15.2-17.9 Years) in 100% of the simulations and regardless of the willingness-to-pay threshold. Only in a worst case scenario was selective retreatment more costly, but remained more effective.

CONCLUSIONS

Selective retreatment, when clinically applicable, is likely to be more cost-effective than full retreatment in endodontically treated molars with persistent apical periodontitis. Our results should be interpreted with caution because the quality of the underlying data is limited.

PROBE 2023 guidelines for reporting observational studies in endodontics: Explanation and elaboration

Observational studies play a critical role in evaluating the prevalence and incidence of conditions or diseases in populations as well as in defining the benefits and potential hazards of health-related interventions. There are currently no reporting guidelines for observational studies in the field of Endodontics. The Preferred Reporting Items for study Designs in Endodontology (PRIDE) team has developed and published new reporting guidelines for observational-based studies called the 'Preferred Reporting items for OBservational studies in Endodontics (PROBE) 2023' guidelines. The PROBE 2023 guidelines were developed exclusively for the speciality of Endodontics by integrating and adapting the 'STrengthening the Reporting of OBservational studies in Epidemiology (STROBE)' checklist and the 'Clinical and Laboratory Images in Publications (CLIP)' principles. The recommendations of the Guidance for Developers of Health Research Reporting Guidelines were adhered to throughout the process of developing the guidelines. The purpose of this document is to serve as a guide for authors by providing an explanation for each of the items in the PROBE 2023 checklist along with relevant examples from the literature. The document also offers advice to authors on how they can address each item in their manuscript before submission to a journal. The PROBE 2023 checklist is freely accessible and downloadable from the PRIDE website (http://pride-endodonticguidelines.org/probe/).

The effect of various in-vitro and ex-vivo parameters on irrigant flow and apical pressure using manual syringe needle irrigation: Systematic review

BACKGROUND

Fluid dynamics is a majorly neglected aspect to be studied in root canal irrigation. The fundamental rule to understand mechanics is to observe patterns of flow during the process. Thus, this work is conducted to do a systemic assessment of the in-vitro and ex-vivo based studies to evaluate the effect of various parameters on the irrigant flow and apical pressure on using a manual syringe needle for root canal irrigation.

METHODS

The literature search was conducted through libraries such as PubMed (Medline), CINAHL, Embase, Scopus and other hand literature from Google Scholar, the British medical library etc. The systematic review was reported following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. As they include studies that were in-vitro and ex-vivo based, the risk of bias of the selected articles was assessed using a customized tool based on the previous literature and parameters evaluated in the studies included.

RESULTS

The literature search resulted in 101 items of which 19 records were included in this review. Results reported that multiple factors and parameters were assessed to evaluate the flow and apical pressures on using manual syringe needle irrigation.

CONCLUSIONS

Present systematic review gives insights in-depth about the irrigation dynamics of manual syringe needle irrigation. Besides, it is inconclusive to compile a single factor or a single parameter contributing to the enhanced irrigant flow and least apical pressures.

Machine learning models for prognosis prediction in endodontic microsurgery

OBJECTIVES

This study aimed to establish and validate machine learning models for prognosis prediction in endodontic microsurgery, avoiding treatment failure and supporting clinical decision-making.

METHODS

A total of 234 teeth from 178 patients were included in this study. We developed gradient boosting machine (GBM) and random forest (RF) models. For each model, 80% of the data were randomly selected for the training set and the remaining 20% were used as the test set. A stratified 5-fold cross-validation approach was used in model training and testing. Correlation analysis and importance ranking were conducted for feature selection. The predictive accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), F1 score, and the area under the curve (AUC) of receiver operating characteristic (ROC) curves were calculated to evaluate the predictive performance.

RESULTS

There were eight important predictors, including tooth type, lesion size, type of bone defect, root filling density, root filling length, apical extension of post, age, and sex. For the GBM model, the predictive accuracy was 0.80, with a sensitivity of 0.92, specificity of 0.71, PPV of 0.71, NPV of 0.92, F1 of 0.80/0.80, and AUC of 0.88. For the RF model, the accuracy was 0.80, with a sensitivity of 0.85, specificity of 0.76, PPV of 0.73, NPV of 0.87, F1 of 0.79/0.81, and AUC of 0.83.

CONCLUSIONS

The trained models were developed by eight common variables, showing the potential ability to predict the prognosis of endodontic microsurgery. The GBM model outperformed the RF model slightly on our dataset.

CLINICAL SIGNIFICANCE

Clinicians can use machine learning models for preoperative analysis in endodontic microsurgery. The models are expected to improve the efficiency of clinical decision-making and assist in clinician-patient communication.

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.

Outcome of Periapical Surgery in Molars: A Retrospective Analysis of 424 Teeth

INTRODUCTION

The objective of this retrospective study was to assess the outcome of periapical surgery in a large number of molars in order to identify possible variables that might affect the outcome.

METHODS

The healing outcome of patients undergoing periapical surgery of molars from October 1999 to October 2019 was retrospectively evaluated. Outcome was dichotomized into "healed" and "nonhealed" using well-established clinical and radiographic healing criteria. The potential influence of patient-, tooth-, and treatment-related parameters on the healing outcome was analyzed.

RESULTS

A total of 424 molars in the same number of patients (45.5% male and 54.5% female) were evaluated. Three hundred seventy-two molars were classified as healed (87.7%). Three significant outcome predictors were identified: 1-year follow-up versus >1-5 years, >5-10 years, and >10 years (95.3% vs 82.2%, 76.3%, and 76.5% healed, respectively; P < .0001); root end filling material with bioceramic root repair material versus mineral trioxide aggregate (96.9% vs. 86.3% healed, respectively; P = .001); and preoperative evaluation based on cone-beam computed tomographic imaging versus 2-dimensional radiography (90.2% vs 81.4% healed, respectively; P = .02). Sex, age, tooth location, type of restoration, attachment level, presence of a post, quality of the root canal filling, technique of root end preparation, administration of antibiotics, and type of surgery had no significant impact on the healing outcome.

CONCLUSIONS

The healed rate for the concave (Retroplast) and cavity (mineral trioxide aggregate, SuperEBA [Staident International, Staines, UK], and bioceramic root repair material) root end preparation technique over all follow-up periods was 84% and 88.5%, respectively. The follow-up period, root end filling material, and preoperative evaluation based on cone-beam computed tomographic imaging had a significant influence on the healing outcome.

Impact of Periodontal Attachment Loss on the Outcome of Endodontic Microsurgery: A Systematic Review and Meta-Analysis

Background and Objectives: Endodontic microsurgery (EMS) aims to eradicate the sources of infection once the apical root resection removes most of the infected anatomical structures and repairs potential procedural errors in the apical region. An endodontic-periodontal lesion yields a pathological communication between the pulp and the periodontium. The purpose of this systematic review and meta-analysis is to evaluate the impact of periodontal attachment loss on the outcome of teeth submitted to EMS. Materials and Methods: PRISMA guidelines were followed. An electronic search was performed in EBSCOhost, Embase and PubMed databases with the following search key: (“endodontic microsurgery” AND “outcome”). No filters were used concerning the year of publication or language. Only randomized clinical trials, prospective and retrospective clinical studies in humans, with a minimum one-year follow-up, defined clinical and radiographic outcome criteria and estimable success rate for endodontic-periodontal lesion were included. Statistical analysis was performed using OpenMeta[Analyst] software. Results: Of a total of 113 articles, 34 were selected for full-text reading after duplicates deletion and title and abstract analysis. Thirteen and six studies were included in the systematic review and meta-analysis, respectively. A total of 2775 pooled teeth were submitted to EMS, of which 492 teeth and 4 roots had periodontal involvement. According to the qualitative analysis, success rates of the endodontic-periodontal group ranged from 67.6% to 88.2%. Meta-analysis revealed that the absence of periodontal attachment loss was predictive of a higher likelihood of success with an odds ratio of 3.14. Conclusions: Periodontal attachment loss presents a risk factor for EMS outcome. Although endodontic-periodontal lesions were associated with lower success rates considering a 1 to 10 years follow-up period, long-term successful prognosis following EMS has been reported, therefore presenting a fully valid and viable therapeutic option for the management of this type of lesions.

A retrospective study of endodontic microsurgery about 302 patients

OBJECTIVES

To investigate the outcome of endodontic microsurgery and analyze the potential prognostic factors, and to evaluate the value of surgical classification by Kim and Kratchman.

METHODS

Collecting clinical examination and radiographical examination of endodontic microsurgery cases (which were followed up at least 1 year), which were classified according to Kim and Kratchman, and we analyzed the outcome of endodontic microsurgery and its potential prognostic factors.

RESULTS

302 patients (400 teeth) who received endodontic microsurgery were included. The one year success rate of endodontic microsurgery was 94.25%. Different classification had significant influences on the outcome of endodontic microsurgery (P<0.05), and the success rate of class B and C were better than those of class D, E, and F. The position of teeth had significant influences on the outcome of endodontic microsurgery (P<0.05). The success rate of maxillary teeth was higher than that of mandibular teeth. The success rate of anterior teeth was higher than that of posterior teeth (P<0.05). The quality of root end filling and first or second surgery had no effect on the outcome (P>0.05).

CONCLUSIONS

Endodontic microsurgery is an effective treatment method for saving affected teeth, and it can get a good result. Tooth position and classification are the potential prognostic factors. The surgical classification of Kim and Kratchman can help to predict the outcome of endodontic microsurgery.

An Update on Endodontic Microsurgery of Mandibular Molars: A Focused Review

Endodontic microsurgery is a highly predictable treatment option in most cases when conventional endodontic treatment is not feasible. Nevertheless, mandibular molars are still considered by clinicians to be the most difficult type of teeth, with the lowest success rate. In recent years, endodontic microsurgery has been attempted more frequently with the emergence of modern cutting-edge technologies such as dental operating microscopes, various microsurgical instruments, and biocompatible materials, and the success rate is increasing. This review describes the current state of the art in endodontic microsurgical techniques and concepts for mandibular molars. Notably, this review highlights contemporary equipment, technology, and materials.

Targeted Endodontic Microsurgery: A Retrospective Outcomes Assessment of 24 Cases

INTRODUCTION

Targeted endodontic microsurgery (TEMS) replaces freehand carbide or diamond bur osteotomy and root-end resection with a guided approach using an end-cutting trephine bur rotated within a guide tube. TEMS departs from traditional endodontic microsurgery in osteotomy size, control of resection level and bevel, surgical time, and resection method; yet, the impact of these departures on clinical outcomes has yet to be assessed. The aim of this study was to assess clinical outcomes of TEMS surgeries at least 1 year after treatment.

METHODS

Potential cases were retrospectively identified from a secure database of all patients who received TEMS in the Air Force Postgraduate Dental School from June 2017-May 2019 with a postsurgical follow-up examination at 1 year or beyond (23 patients with 24 teeth). Two board-certified endodontists completed a calibration exercise before assessing radiographs. A retrospective outcomes assessment was conducted considering follow-up clinical and radiographic findings to assign 1 of 3 healing designations: complete healing, reductive healing, or failure.

RESULTS

Combined clinical and radiographic data led to 20 designations of complete healing, 2 designations of reductive healing, and 2 failures (91.7% success rate). Considered alone, radiographic criteria for complete healing were met for 20 cases, reductive healing for 3 cases, and radiographic failure for 1 case.

CONCLUSIONS

This limited retrospective outcomes assessment is an early indication that TEMS-guided trephine bur root-end resection leads to similar success as is established for freehand carbide and diamond bur resection. Controlled clinical trials with long-term follow-up are warranted.

The Buffalo study: Outcome and associated predictors in endodontic microsurgery- a cohort study

AIM

To (i) evaluate and compare the outcome of endodontic microsurgery (EMS) using periapical radiographs (PAs) and cone-beam computed tomography (CBCT) scans; (ii) identify prognostic factors affecting the outcome; and (iii) correlate the effect of guided tissue regeneration (GTR) on the pattern of apical bone remodelling.

METHODOLOGY

Eighty-two patients (101 teeth) who received EMS were included and followed-up using clinical and radiographic examinations (PAs and CBCT scans). Two calibrated endodontists evaluated the radiographic healing (favourable or unfavourable) by assessing PAs and CBCT. The success (favourable radiographic outcome with no clinical symptoms) and survival rates (tooth retention without clinical symptoms) were calculated, and the cause of failure (diseased or fractured) was identified. Pre-treatment (age, sex, tooth type, position, sequence of treatment, quality of root canal before surgery, presence/absence of through-and-through lesion, presence/absence apico-marginal defect) and treatment (presence/absence of errors during surgery, type of error (major or minor), retro-preparation depth, presence/absence of an isthmus, retro-filling material used, presence/absence bone graft material and/or resorbable membrane) factors were recorded. Data were analysed statistically to determine the inter-observer, intra-observer and inter-radiographic agreements. Univariate, bivariate and logistic regression analysis were used to determine prognostic factors affecting the outcome and the effect of GTR on the pattern of apical bone remodelling. The significance level was set at 5%.

RESULTS

Sixty-eight patients (83 teeth) presented for outcome evaluation (recall rate: 84%). The survival rate was 93%. The success rate was 88% using PA and 86% using CBCT when vertical root fracture (VRF) cases were included and 94% using PAs, and 91% using CBCT when VRF cases were excluded. The intra- and inter-observer agreements were substantial using CBCT, slight to a fair agreement using PA (P < 0.001), and slight to moderate for inter-radiographic agreement. The occurence of a major procedural error during surgery was the only negative predictor for the outcome of EMS (P = 0.013). GTR did not affect the success rate or the type of healing when assessed using PA but it affected the type of healing on CBCT scans (complete vs incomplete healing) and the pattern of cortical plate remodelling (P < 0.001).

CONCLUSION

The success and survival rate of endodontic microsurgery was very high, and the occurrence of a major procedural error during surgery was the only factor affecting the outcome. GTR did not improve the outcome, but did affect the quality of apical bone remodelling following EMS.

Evaluation of Root-End Preparation with Two Different Endodontic Microsurgery Ultrasonic Tips

The aim of this study is to compare root-end preparation performed with two different ultrasonic tips-CVDentus and NSK-and respective time requirements. After root-end resection, 32 teeth were randomly divided in two groups, according to the ultrasonic tip used for root-end preparation. Preparation time was recorded. Photomicrographs were taken to assess the following parameters: root surface microcracking, marginal integrity and presence of debris. One ultrasonic tip from each group was analyzed through scanning electron microscopy before and after root-end preparation. The significance level was set at α = 0.05. Incidence of microcracks in both groups was 12.5%. Solely intracanal microcracking was found, consistently positioned within the widest side of the remaining dentine. No statistically significant differences were verified between both experimental groups regarding marginal integrity (p = 0.102) and preparation time (p = 0.780), whereas statistical differences (p = 0.003) were found concerning the presence of debris (the minimum registered score was mostly verified in CVDentus group). NSK tips showed major morphological changes, with extensive surface wear and noticeable loss of particles, which was not verified on CVDentus tips. Our findings suggest significant differences regarding root-end preparation walls quality, with CVDentus tips showing better results. Concerning microcracking, as well as preparation time and marginal integrity, both ultrasonic tips showed similar results. Qualitative analysis exposed NSK tips major morphological changes and wear after use, which was not verified on CVDentus tips.

Prognostic Factors of Long-Term Outcomes in Endodontic Microsurgery: A Retrospective Cohort Study over Five Years

The aim of this study was to analyze the long-term outcomes of endodontic microsurgeries in a cohort and identify their association with prognostic factors. A cohort of endodontic microsurgeries followed up periodically with complete clinical and radiographic records for at least 5 years were reviewed retrospectively. Their survival and healing status and profile characteristics were analyzed by Pearson chi-square test and logistic regression (α = 0.05) to identify prognostic factors that influenced outcomes. Of 652 cases in the cohort, 225 (34.5%) were included. The mean follow-up period was 90.4 months (range, 60–168 months). The long-term success rate was 80.5%, and the 5-year survival rate was 83.5%. Logistic regression showed higher success in anteriors compared to molars (OR = 5.405, (95% CI, 1.663–17.571; p = 0.005)) and in teeth with crown restorations (OR = 10.232, (95% CI, 3.374–31.024; p < 0.001)). Conversely, lower success was found in teeth with periodontal disease (OR = 0.170, (95% CI, 0.032–0.900; p = 0.037)) and maxillary sinus involvement (OR = 0.187, (95% CI, 0.035–0.994; p = 0.049)). Endodontic microsurgery has a highly favorable long-term outcome. Tooth position, crown restoration, periodontal disease, and maxillary sinus involvement were identified as main prognostic factors.