Prognostic Factors after Endodontic Microsurgery: A Retrospective Study of 111 Cases with 5 to 9 Years of Follow-up

Two- and three-dimensional healing assessment after endodontic microsurgery in through-and-through periapical lesions: 5-year follow-up from a randomized controlled trial

AIM

To evaluate clinical and radiographic outcome of endodontic microsurgery in through-and-through periapical lesions at 1-year and 5-year follow-up with adjunct use of platelet-rich plasma (PRP).

METHODOLOGY

Thirty-two patients with large through-and-through periapical lesions were randomized in platelet-rich plasma (PRP) group and control group. Two-dimensional (2D) healing was evaluated with Molven's criteria and three-dimensional (3D) healing with modified PENN 3D criteria. Healing at resection plane (R), apical area (A), buccal cortex (BC), palatal cortex (PC) and overall bone healing (B) was assessed using CBCT scans. The volume of lesion was measured using ITK-Snap software. The analysis included comparison of 1- to 5-year intragroup (Friedman test/McNemar test) and intergroup scoring (Chi-square/ Mann-Whitney test). Logistic regression analysis was performed to determine the effect of various factors on healing at 5 years.

RESULTS

Out of 32 patients/59 teeth evaluated after 1-year of endodontic microsurgery, 24 patients/44 teeth reported at 5 - year follow-up. Healing assessment with modified PENN 3D criteria revealed improvement in overall success rate of 66.7% at 1 year to 83.3% at 5 years, with no deterioration in any healing category. PRP group exhibited significantly better 3D healing than control group; both at 1 year (84.6% vs. 45.5%) and 5 years (100% vs. 63.6%). A significantly higher number of completely healed teeth were observed in PRP group than the control group at 5 years with respect to R, BC and B parameters. A volume reduction of 88% (91.4% PRP, 84% control) was depicted at 1 year and 94% (97.1% PRP, 91.1% control) at 5 years. None of the recorded factors including age, gender, size of lesion, preoperative swelling and sinus, histology of lesion, use of PRP, tooth location, preoperative buccal bone had significant effect on 3D healing at 5 years.

CONCLUSIONS

This 5-year study suggested improvement in 3D radiographic healing of large through-and-through periapical lesions from 1 to 5 years with no deterioration in any healing parameter in both control and PRP groups. The additional use of PRP led to significantly better healing in such lesions. RACB index using CBCT allows better estimation of healing at resected, apical and cortical plane over modified PENN 3D or Molven's criteria.

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).

A novel simplified approach for endodontic retrograde surgery in short single-rooted teeth

BACKGROUND

High technical thresholds, long operative times, and the need for expensive and specialized equipment impede the widespread adoption of endodontic microsurgery in many developing countries. This study aimed to compare the effects of a simplified, cost-effective, and time-efficient surgical approach involving orthograde obturation using biological ceramic material greater than 6 mm combined with apicoectomy for single-rooted teeth with short lengths with those of the conventional and current standard methods.

MATERIALS AND METHODS

Forty-five premolars equally categorized into three groups: conventional surgery group, standard surgery group, and modified surgery group. A µCT scan was used to calculate the volume of voids. A micro-leakage test and scanning electron microscope (SEM) were performed to assess the sealing effect. Additionally, four cases of chronic periapical periodontitis in the anterior region were selected, and the patients received either the modified approach or the standard surgery for endodontic microsurgery.

RESULTS

The volumes of voids in the apical 0-3 mm of the modified group and the standard group were comparable. The micro-leakage test and SEM examination demonstrated closely bonded fillings in the dentinal walls in both the modified surgery group and standard surgery group. The outcomes of the preliminary application of this modified procedure on patients were successful at the time of the follow-up cutoff.

CONCLUSIONS

The modified surgery group exhibited similar root canal filling and apical sealing abilities with the standard procedure for single-rooted teeth with short lengths (< 20 mm). The preliminary application of this modified surgical procedure achieved favorable results.

Analysis of mandibular molar anatomy in Taiwanese individuals using cone beam computed tomography

Background/purpose

Before periapical surgery in the mandibular posterior teeth is performed, the thicknesses of the buccal alveolar bone wall and buccolingual root might be a critical issue. This study aimed to assess the anatomical structure of the posterior region of the mandible in Taiwanese individuals using cone-beam computed tomography (CBCT).

Materials and methods

The CBCT images of 96 Taiwanese individuals (51 male and 45 female), which included 192 mandibular first molars and 192 mandibular second molars, were imported into medical imaging software to measure the buccal alveolar bone thickness and buccolingual root thickness at 3 mm above the root apex. Statistical analysis was conducted to examine the impact of tooth position, gender, and age on the anatomical position of mandibular molars.

Results

The buccal alveolar bone thickness at 3 mm above the root apex of the mandibular second molar demonstrates a significantly higher value when compared to that of the first molar. Nonetheless, concerning the buccolingual root thickness, no significant differences were observed between these two teeth. In addition, the buccal alveolar bone thickness and buccolingual root thickness at 3 mm above the root apex may not be influenced by gender and age.

Conclusion

The anatomical structures of the posterior region of the mandible in Taiwanese individuals exhibited variations between the mandibular first and second molars. However, these differences were not influenced by gender or age.

The effect of hard tissue defects on the clinical outcome of endodontic microsurgery: a systematic review and meta-analysis

OBJECTIVES

The purpose of this systematic review was to appraise the existing literature on the effect of hard tissue defects on the clinical outcome of endodontic microsurgery (EMS).

METHODS

MEDLINE (PubMed), Embase, Web of Science, Cochrane Library and grey literature were searched from January 2000 to May 2023. Study selection and data extraction were performed in duplicate. Eligible studies were critically appraised for the risk of bias using the Cochrane Risk of bias tool. The quality of evidence was assessed using GRADE. Review Manager (RevMan Computer program Version 5.4, The Cochrane Collaboration, 2020) was utilized and the Mantel Haenszel fixed or random effects model was applied, depending on the heterogeneity of the studies. Meta-analysis was performed to estimate the Risk ratio (RR) and 95% Confidence Interval (CIs) to correlate the effects of these factors on treatment outcomes.

RESULTS

Nineteen studies were included. The EMS overall pooled success rate was 84.5%. Five characteristics of hard tissue were identified. The size of the lesion (Small ≤ 5 mm: 78.4% vs. Large > 5 mm: 63.3%, RR = 1.12, 95% CI 1.00-1.26, P ≤ .05), significantly affected the outcomes of EMS. Endodontic lesions exhibited slightly better outcomes than endodontic-periodontal lesions (81.4% vs. 68.2%, RR = 1.14 95% CI 0.98-1.33, P > .05). Cases with the height of the buccal bone > 3 mm also exhibited slightly better outcomes (91.5% vs. 71.4%, RR = 1.20, 95% CI 0.88-1.62, P > .05). Additionally, through and through lesions exhibited better outcomes when grafting was completed during the EMS procedure both in 2D (RR = 1.12 95% CI 0.97-1.29, P > .05) and 3D evaluation ((RR = 1.28 95% CI 0.69-2.37 P > .05). The overall quality of evidence was graded as low to high.

CONCLUSION

With a low to high quality of evidence, the size of the lesion is a key prognostic variable that significantly affects the outcome of EMS, as lesions ≤ 5 mm exhibit better outcomes as compared to larger lesions.

CLINICAL SIGNIFICANCE

The presence of hard tissue defects can affect the outcome of endodontic microsurgery (EMS). The presented data can aid the clinicians' decision-making process by examining certain pre-operative prognostic variables, when considering EMS as a treatment option. Clinical cases with more favorable hard tissue characteristics lead to a better prognosis in EMS.

Efficacy of mixture of injectable-platelet-rich fibrin and type-1 collagen particles on the closure of through-and-through periapical bone defects: A randomized controlled trial

AIM

To determine the efficacy of a combination of injectable-platelet-rich fibrin and type-1 collagen particles on the healing of through-and-through periapical bone defect and subsequent closure of bony window.

METHODOLOGY

The clinical trial was registered in ClinicalTrials.gov (NCT04391725). Thirty-eight individuals with radiographic evidence of periapical radiolucency in maxillary anterior teeth and confirmed loss of palatal cortical plates in cone beam computed tomographic imaging were randomly assigned to either the experimental group (n = 19) or the control group (n = 19). A mixture of i-PRF and collagen as a graft was applied to the defect in adjunct to periapical surgery in the experimental group. No guided bone regeneration procedures were used in the control group. The healing was evaluated using Molven's (2D) and modified PENN 3D (3D) criteria. Percentage reduction of the buccal and palatal bony window area, and complete closure of through-and-through periapical bony window (tunnel defect) were assessed using Radiant Diacom viewer software (Version 4.0.2). The reduction in the periapical lesion area and volume was measured using Corel DRAW and ITK Snap software.

RESULTS

Thirty-four participants (18 and 16 in the experimental and control groups respectively) reported for follow-up at 12 months. There was 96.9% and 97.96% reduction of buccal bony window area in the experimental and control groups respectively. Similarly, palatal window showed 99.03% and 100% reduction in the experimental and control groups respectively. No significant difference in both buccal and palatal window reduction was noticed between the groups. A total of 14 cases (seven in the experimental group and seven in the control group) showed complete closure of through-and-through bony window. No significant difference in clinical, 2D and 3D radiographic healing, percentage reduction in area and volume was observed between the experimental and control groups (p > .05). Neither the area nor the volume of lesion, and the size of buccal or palatal window had significant effect on healing of through-and-through defects.

CONCLUSION

Endodontic microsurgery results in high success rate in large periapical lesions with through-and-through communication with more than 80% reduction in volume of lesion and size of both buccal and palatal window after 1 year. A mixture of type-1 collagen particles and i-PRF, adjunct to periapical micro-surgery did not improve the healing in through-and-through periapical defects.

Clinical and radiological outcomes of dynamic navigation in endodontic microsurgery: a prospective study

OBJECTIVES

This study was aimed at evaluating the clinical and radiological outcomes of novel dynamic navigation (DN)-aided endodontic microsurgery (EMS), with an analysis of potential prognostic factors.

MATERIALS AND METHODS

Forty-six teeth from 32 patients who received DN-aided EMS were included. Clinical and radiographic assessments were performed at least 1 year postoperatively. Two calibrated endodontists assessed radiological outcomes according to two-dimensional (2D) periapical radiography (PA) and three-dimensional (3D) cone-beam computed tomography (CBCT) imaging using Rud's and Molven's criteria and modified PENN 3D criteria, respectively. Fisher's exact test was used for statistical analysis of the predisposing factors.

RESULTS

Of the 32 patients with 46 treated teeth, 28 with 40 teeth were available for follow-up. Of the 28 patients, four (five teeth) refused to undergo CBCT and only underwent clinical and PA examinations, and the remaining 24 (35 teeth) underwent clinical, PA, and CBCT examinations. Combined clinical and radiographic data revealed a 95% (38/40) success rate in 2D healing evaluations and a 94.3% (33/35) success rate in 3D healing evaluations. No significant effect was found in sex, age, tooth type, arch type, preoperative lesion volume, preoperative maximum lesion size, presence/absence of crown and post, and the root canal filling state on the outcome of DN-aided EMS.

CONCLUSIONS

DN-aided EMS has a favorable prognosis and could be considered an effective and reliable treatment strategy. Further investigations with larger sample sizes are required to confirm these results.

CLINICAL RELEVANCE

DN-aided EMS could be considered an effective and reliable treatment strategy.

Endodontic Surgery of the Palatal Root of a Maxillary Molar Associated with Simultaneous Management of a Maxillary Sinus Lesion

This case report describes a particular application of endodontic microsurgery with a palatal approach in the presence of a radiopaque lesion inside the maxillary sinus. The patient presented complaining of pain related to the first maxillary molar and events of nasal obstruction and facial pain in the cheek and nasal area. The endodontic orthograde treatment and retreatment were done, respectively, 7 and 4 years earlier. The cone-beam computed tomography (CBCT) scan taken before the treatment showed two separate lesions: one associated with the palatine root of the molar and another one inside the maxillary sinus. The patient agreed to solve both problems in one surgical step: endodontic surgery of the palatine root with palatal access with the simultaneous asportation of a lesion from the maxillary sinus floor. Complete bone healing of the periapical area and the maxillary sinus was visualized on intra-oral radiographs, and CBCT was taken one year after the treatment. As far as the authors know, no one in literature has ever described this approach and solved in such a conservative way both the problems at the tooth and in the maxillary sinus.

Effect of orthodontic treatment on the periapical radiolucency of endodontically treated teeth: a CBCT analysis

BACKGROUND

This study aimed to evaluate periapical radiolucency of endodontically treated teeth before and after orthodontic treatment using cone-beam computed tomography (CBCT).

METHODS

Patients who underwent orthodontic treatment at Wonkwang University Daejeon Dental Hospital between January 2009 and June 2022 were included based on the following criteria: root canal treatment, and availability of CBCT images taken before and after orthodontic treatment with an interval of > 1 year between both scans. Patients with primary teeth or orthodontic tooth extractions were excluded. The size of the periapical radiolucency (SPR) of the endodontically treated tooth was evaluated using CBCT. Pre-orthodontic treatment CBCT images and the latest post-orthodontic treatment CBCT images were analyzed. The selected teeth were further categorized based on the orthodontic duration, CBCT interval, the patient sex and age, the tooth type and position (maxilla or mandible), and quality of root canal obturation. Statistical analyses were performed to evaluate changes in SPR using the paired t-test and multiple regression analysis.

RESULTS

In total, 115 teeth (37 anterior teeth, 22 premolars and 56 molars) from 61 patients (age, 14-54 years) were included, with 39 teeth from male patients and 76 teeth from female patients. The age was ranged between 14 and 54 years old, and mean age was 25.87 years old. The mean CBCT interval and orthodontic treatment period were 43.32 months and 36.84 months, respectively. Seventy-five teeth showed good obturation quality, 80 were not used as anchors during orthodontic treatment, and 71 were maxillary. The SPR size increased after orthodontic treatment for 56 teeth and decreased for 59 cases. The average change in SPR was -0.102 mm and the difference was not significant. Significant decrease of SPR were observed between female patients (p = 0.036) and maxillary teeth (p = 0.040).

CONCLUSION

Orthodontic treatment had no significant impact on the changes in the SPR in endodontically treated teeth in most categories. However, there was a significant difference among females and the maxillary teeth. In both categories, the size of radiolucency decreased significantly.

Clinical Effect Evaluation of Concentrated Growth Factor in Endodontic Microsurgery: A Cross-Sectional Study

INTRODUCTION

Concentrated growth factor (CGF) is the third-generation platelet concentrate product. This study aimed to evaluate whether the use of CGF during endodontic microsurgery had a positive influence on surgical outcomes.

METHODS

Fifty-four patients who underwent endodontic microsurgery from January 2017 to November 2021 were enrolled. They were assigned to the CGF and the control group according to whether CGF was used during the surgery and followed up at 6, 12, and 18 months post-surgery. Preoperative classification of the cases and follow-up radiographic outcomes were based on Kim's classification and Molven's criteria respectively and evaluated by two calibrated endodontists. Student t-test and Chi-square test were used to assess the baseline of two groups. Rank sum test was used to determine whether CGF had an impact on the surgical outcome.

RESULTS

Thirty-one patients (41 periapical lesion sites) were included in the CGF group, and twenty-three patients (26 periapical lesion sites) were included in the control group. The overall success rate of endodontic microsurgery was above 90%. The baseline of the two groups had no difference (P<0.05). In the CGF group, the success rate was always 100% in three follow-ups, while the success rate was 84.2%, 92.8%, and 90% respectively in the control group. The success rate between the CGF group and the control group was statistically significant in all three follow-up points (P<0.05).

CONCLUSIONS

The application of CGF during endodontic microsurgery might have a positive influence on surgical outcomes, thus, its prognosis. However, higher-grade evidence is needed to demonstrate its role.

Non-surgical Root Canal Treatment of an Upper First Molar With an Unusual Morphology: A Case Report

This paper presents the unusual morphology of an upper right first molar with two roots, each containing a single canal, in a patient seeking emergency endodontic treatment. Clinical and radiographic examinations revealed the unusual root canal morphology of the tooth, which required further investigation using cone beam computed tomography (CBCT) imaging, which confirmed this unusual anatomical structure. It was also noted that the upper right first molar was asymmetrical to the upper left first molar, which had the normal three-root morphology. The buccal and palatal canals were instrumented using ProTaper Next Ni-Ti rotary instruments and enlarged to ISO size 30, with a taper of 0.7; irrigated with 2.5% NaOCl; filled with gutta-percha using the warm-vertical-compaction technique, with the aid of a dental operating microscope (DOM); and then confirmed via periapical radiograph. The DOM and CBCT are valuable aids that helped us to confirm the endodontic diagnosis and treatment of this unusual morphology.

Factors that influence the outcomes of surgical endodontic treatment

Surgical endodontic treatment encompasses a broad spectrum of procedures, amongst which root-end cavity preparation and filling, retrograde root canal treatment and through-and-through endodontic surgery, may be classified under the umbrella term 'Root-end surgery'. This narrative review considers the available data on periapical healing, soft tissue healing, tooth survival and oral health-related quality of life (OHRQoL), following root-end surgery and the factors that affect its outcomes. The pooled periapical healed rate for the studies published up to 2021 was 69% (95% CI: 65%, 73%) but increased to 76% (95% CI: 66%, 86%) when only data from the 2020's studies were analysed. The prognostic factors consistently reported for periapical healing have included: pre-operative periapical lesion with complete loss of buccal plate, quality of root-end preparation, remaining thickness of apical root dentine and restorative status. Soft tissue healing of the reflected flap was found to have a positive association with periapical healing. The survival rates following root-end surgery range from 48% to 93%, with failure of periapical healing associated with root and crown fracture, being the predominant reasons for tooth extraction. The factors influencing impact of root-end surgery on patients' quality of life could not be adequately evaluated due to design flaws in the available studies. In conclusion, if root canal treatment failure due to leakage through cracks, fractures or restoration margin are excluded, the remaining cases may represent localized residual infection and inflammation at the periapex that should be amenable to predictable management with the aid of modern root-end surgery.

The effect of periapical lesion size on the success rate of different endodontic treatments: a systematic review and meta-analysis

INTRODUCTION

This systematic review evaluated the effect of periapical lesion (PL) size on the success rate of different endodontic treatments, including root canal treatment (RCT), non-surgical retreatment (NSR), and apical surgery (AS).

METHODS

Cohorts and randomized controlled trials investigating the outcomes of endodontic treatment of permanent teeth with PL and its size were identified electronically through Web of Science, MEDLINE, Scopus, and Embase databases. Two reviewers independently conducted the study selection, data extraction, and critical appraisal process. The quality of the included studies was evaluated using the Newcastle-Ottawa Scale and the 11-item Critical Appraisal Skills Program checklist for randomized controlled trials. The success rates of the endodontic treatments (small lesions and large lesions) were estimated using the rate ratios (RRs) with an associated 95% confidence interval (CI).

RESULTS

Out of 44 included studies, 42 were cohort, and 2 were randomized controlled trials. Thirty-two studies had poor quality. For the meta-analysis, five studies in RCT, 4 in NSR, and 3 in AS were considered. The RR of the endodontic treatment success in PLs was 1.04 in RCT (95% CI, 0.99-1.07), 1.11 in NSR (95% CI, 0.99-1.24), and 1.06 in AS (95% CI, 0.97-1.16). Only sub-group analysis of long-term follow-up of RCT showed a significantly higher success rate in small lesions than in large lesions.

CONCLUSIONS

Considering the quality of studies and variation in outcomes and size classification, our meta-analysis demonstrated that the PL size had no significant effect on the success rate of different endodontic treatments.

Prognostic Factors in Endodontic Surgery Using an Endoscope: A 1 Year Retrospective Cohort Study

This retrospective study clarified the success rate of endoscopic endodontic surgeries and identified predictors accounting for successful surgeries. In this retrospective study, 242 patients (90 males, 152 females) who underwent endoscopic endodontic surgery at a single general hospital and were diagnosed through follow-up one year later were included. Risk factors were categorized into attributes, general health, anatomy, and surgery. Then, the correlation coefficient was calculated for the success or failure of endodontic surgery for each variable, the odds ratio was calculated for the upper variable, and factors related to the surgical prognosis factor were identified. The success rate of endodontic surgery was 95.3%, showing that it was a highly predictable treatment. The top three correlation coefficients were post, age, and perilesional sclerotic signs. Among them, the presence of posts was the highest, compared with the odds ratio, which was 9.592. This retrospective study revealed the success rate and risk factors accounting for endoscopic endodontic surgeries. Among the selected clinical variables, the presence of posts was the most decisive risk factor determining the success of endodontic surgeries.

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.

Healing after surgical retreatment at four time points: A retrospective study

AIM

To evaluate the outcome of surgical retreatment at four time points, that is 6, 12, 24 and 48 months post-operatively, and to search for prognostic factors that may affect the outcome.

METHODOLOGY

Clinical records and intraoral periapical radiographs were collected from patients who had undergone surgical retreatment between 2009 and 2015 and attended 6-, 12-, 24- and 48-month follow-up visits. Surgical retreatment was performed by one endodontist and involved minimal root-end resection and maximal length root-end preparation using prebent ultrasonic files. Outcomes were categorized as complete, incomplete, uncertain or unsatisfactory healing, based on clinical and radiographic findings. The complete and incomplete categories were pooled and considered successes, while uncertain and unsatisfactory outcomes were considered failures. Changes in healing outcome were analysed using the McNemar-Bowker test, and prognostic factors were analysed using univariate analysis.

RESULTS

The study cohort included 297 patients with 384 teeth. The overall success rate after 48 months was 90.6% compared with 88.5%, 93% and 92.4% after 6, 12 and 24 months respectively. Age, gender, presence of isthmus and length of canal preparation had no significant influence on the outcome. Lesion size and tooth type had a significant influence only after 6 and 12 months, respectively, with no significant differences at other time points. Fifty per cent of the teeth classified as unsatisfactory or uncertain healing at the 6 months follow-up improved to incomplete or complete healing after 12 months. None of the cases classified as unsatisfactory healing after 12 months subsequently improved, and only 2 cases that were classified as uncertain healing after 12 months improved after 24 months.

CONCLUSIONS

Surgical retreatment was found to be a predictable procedure with a high success rate of 90.6% after 4 years. Over the follow-up periods, only a minor regression in the success rate was found. The 12 months follow-up results closely indicated the long-term outcome of surgical retreatment.

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.

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.