Comparative assessment of the incidence of vertical root fractures between conventional versus surgical endodontic retreatment

Endodontic Microsurgery Outcomes over 10 Years and Associated Prognostic Factors: A Retrospective Cohort Study

INTRODUCTION

This retrospective cohort study aimed to evaluate long-term healing outcomes (10-17.5 years) after contemporary endodontic microsurgery (EMS) and identify the associated prognostic factors.

METHODS

Clinical and radiographic data of an EMS cohort (2006-2013) from the electronic database of the dental hospital were reviewed retrospectively by 2 independent examiners to determine their survival and healing outcomes, and potential prognostic factors were analyzed by Cox proportional hazards regression and logistic regression (α = 0.05).

RESULTS

Through strict inclusion and exclusion criteria and 721 EMS-treated teeth in the cohort, 309 (42.9%) were included (male = 35.0%; female = 65.0%; age = 45.83 ± 15.53 years) with a mean final follow-up of 152.26 ± 26.37 months (range, 120-211 months; median = 148 months). Clinical and radiographic assessments found an 80.5% 10-year survival rate with 63.4% of success. Collectively, tooth type, tooth mobility, preoperative lesion size, clinical crown-to-root ratio, and crown restorations at follow-up were significantly associated with long-term success and survival over 10 years.

CONCLUSIONS

The preoperative status and condition of the tooth including its alveolar bone support and adequate full-crown restorations may be relevant prognostic determinants of success and survival after EMS over time.

Retrospective Assessment of Endodontically Treated Teeth Replaced by Dental Implants

INTRODUCTION

This study investigated endodontically treated teeth that were replaced by dental implants at the University of North Carolina (UNC) at Chapel Hill School of Dentistry. The primary objective of this study was to determine the reasons leading to the extraction of endodontically treated teeth and their subsequent replacement with dental implants. The secondary objective was to evaluate the proportion of these teeth that, according to experienced endodontists, could have been preserved.

METHODS

The UNC-Chapel Hill's dental electronic health records between 2004 and 2019 were probed for implant placement that replaced root canal-treated teeth. Preextraction radiographs and clinical charts were examined to ascertain the primary reason related to the extraction and to compile a profile for each case. In cases in which endodontic failure was the primary reason for extraction, radiographs and clinical findings were evaluated by 2experienced endodontists to assess potential treatment options.

RESULTS

Between 2004 and 2019, 29.3% (1564 of 5229) of teeth replaced by dental implants at UNC School of Dentistry had undergone root canal treatment, with the mandibular first molar being the most commonly replaced tooth. The leading reasons for extraction were recurrent caries associated with defective restoration (26.6%), fracture of coronal structure (21.5%), vertical root fracture (20.9%), compromised periodontal condition (13.8%), and endodontic failure (2.4%). Two experienced endodontists evaluated extractions due to endodontic failure and concluded that 61.7% of them could have been candidates for endodontic retreatment.

CONCLUSION

Substantial loss of tooth structure was the leading cause of extraction of root canal-treated teeth, followed by vertical root fracture and periodontal disease. Although endodontic failure constituted a minor portion of the reasons for extraction, a considerable number of teeth were extracted due to vertical root fractures following root canal treatment. A significant proportion of the extracted teeth due to endodontic failure could have been considered as potential candidates for endodontic retreatment.

Comparison of Endodontic Failures between Nonsurgical Retreatment and Endodontic Surgery: Systematic Review and Meta-Analysis with Trial Sequential Analysis

Background and Objectives: In the presence of a persistent endodontic lesion or endodontic failure, the alternative for the recovery of the dental element is endodontic retreatment or endodontic surgery, which consists in the surgical removal of the root apices with retrograde closure of the endodontium. The objective of this systematic review and meta-analysis was to provide an updated value of the Risk Ratio between the two types of treatment in order to offer to clinicians who propose a non-surgical endodontic retreatment or an endodontic surgery a direct comparison. Materials and Methods: The revision was performed according to PRISMA indications: three databases (PubMed, Scopus and Cochrane register) were consulted through the use of keywords relevant to the revision topic: surgical endodontic retreatment, endodontic retreatment, apicoectomy. This search produced 7568 records which, after eliminating duplicates and applying the inclusion and exclusion criteria, resulted in a total of seven included articles. The meta-analyses were conducted by applying fixed-effects models, given the low percentage of heterogeneity. In addition, trial sequency analysis (TSA) was performed for the analysis of the statistical power of the results and GRADE for the quality of the evidence. Results: The results of the meta-analyses' data report an aggregate risk ratio (RR) between non-surgical endodontic retreatment and surgical endodontic retreatment of: 1.05 [0.74, 1.47] at one year of follow-up; RR 2.22 [1.45, 3.41] at two years of follow-up; an RR 1.08 [0.73 1.62] for a follow-up period of 3-4 years; and an RR 0.92 [0.53, 1.61] for a follow-up period of 8-10 years. Conclusions: The results of the present meta-analysis show that in the long term, the risk of failure is identical for the two groups, and there is only a slightly higher risk of failure for non-surgical endodontic retreatments, when only two years of follow-up are considered.

Vertical root fractures in root treated teeth-current status and future trends

Vertical root fracture (VRF) is a common reason for the extraction of root filled teeth. The accurate diagnosis of VRF may be challenging due to the absence of clinical signs, whilst conventional radiographic assessment is often inconclusive. However, an understanding of the aetiology of VRFs, and more importantly, the key predisposing factors, is crucial in identifying teeth that may be susceptible. Thorough clinical examination with magnification and co-axial lighting is essential in identifying VRFs, and although CBCT is unable to reliably detect VRFs per se, the pattern of bone loss typically associated with VRF can be fully appreciated, and therefore, increases the probability of correct diagnosis and management. The prevalence of VRFs in root filled teeth is significantly greater than in teeth with vital pulps, demonstrating that the combination of loss of structural integrity, presence of pre-existing fractures and biochemical effects of loss of vitality, are highly relevant. Careful assessment of the occlusal scheme, presence of deflective contacts and identification of parafunctional habits is imperative in both preventing and managing VRFs. Furthermore, anatomical factors such as root canal morphology, may predispose certain teeth to VRF. The influence of access cavity design and root canal instrumentation protocols should be considered although the impact of these on the fracture resistance of root filled teeth is not clearly validated. The post-endodontic restoration of root filled teeth should be expedient and considerate to the residual tooth structure. Posts should be placed 'passively' and excessive 'post-space' preparation should be avoided. This narrative review aims to present the aetiology, potential predisposing factors, histopathology, diagnosis and management of VRF and present perspectives for future research. Currently, there are limited options other than extraction for the management of VRF, although root resection may be considered in multi-rooted teeth. Innovative techniques to 'repair' VRFs using both orthograde and surgical approaches require further research and validation. The prevention of VRFs is critical; identifying susceptible teeth, utilizing conservative endodontic procedures, together with expedient and appropriate post-endodontic restorative procedures is paramount to reducing the incidence of terminal VRFs.

Vertical root fractures: A time-dependent clinical condition. A case-control study in two colombian populations

Background

This nested case-control study can be viewed as an efficient way to sample subjects from a large cohort study case-control study aimed to analyze the effect of different clinical factors on the appearance of vertical root fractures in endodontically-treated teeth (ETT) over time.

Material and Methods

By matching 90 cases and 270 controls nested in a cohort of 450 patients. Incident “cases” included those ETT in which a confirmed VRF. The “controls” were ETT with clinical and radiographic evidence of normality. When an “incident case” was detected, three random “controls” according to the evaluation time registered in years were selected. Time interval corresponded to the exposure time from the end of the endodontic treatment until the tooth was included in the study. Demographic and clinical parameters included: age, gender, type, and location of the tooth, type of endodontic treatment, number of appointments necessary to complete the endodontic treatment, use of intra-canal medication, the apical extension of the filling, type of coronal restoration, the role of the tooth in the rehabilitation treatment, presence of intra-radicular posts, and presence of an adjacent implant, were analyzed over time. Statistical analysis: univariate descriptive analysis, Pearson’s χ2 test, and a logistic regression model adjusted for the most significant variables with a 95% confidence interval.

Results

The prevalence of vertical root fractures was 16.42%. The multivariate analysis confirmed that re-treatment (OR:12.19; OR:4.28;P<0.05) lasting five to ten years and intra-canal medication (OR:6.16;P=0.004) for more than eleven years significantly more associated with the risk of vertical root fracture. For teeth with intra-canal post or direct coronal restorations, the risk of vertical root fracture was three times lower.

Conclusions

Endodontic re-treatment and the use of intracanal medication such as calcium hydroxide should be considered primary and secondary risk factors, respectively, according to the appearance of VRF over time.

Key words:Apical surgery, endodontic re-treatment, endodontically-treated teeth, risk factors, vertical root fracture.

Repair of teeth with cracks in crowns and roots: An observational clinical study

AIM

This retrospective observational study investigated the survival rate of teeth with radicular cracks that were restored using composite materials.

METHODOLOGY

The study was approved by the Ethical Committee of Sistema Sanitario Nazionale (prot. N°2370CELazio1), Clinicaltrials.gov identifier: NCT04430205. Between 1991 and 2019, 87 teeth with radicular cracks (87 patients [46 men, 41 women, mean age 50.2 years]) were treated with adhesive composite restorations. Forty-five cracks were observed in the maxillary posterior teeth (molars and premolars), 40 in the mandibular posterior teeth and only two cracks in the anterior teeth, both in maxilla. Based on the depth of the crack, teeth were categorized as proximal radicular cracked teeth (PRCT), in which the fracture line was restricted within the pulpal floor or the coronal one-third of the root and deep radicular cracked teeth (DRCT), in which the fracture line extended to the middle and apical thirds of the root canal up to the apex. Bone loss/recovery was evaluated radiographically at 1-year follow-up. All patients were treated using surgical microscopy by the same operator. Logistic regression analysis was performed to determine independent predictors of extraction. Kaplan-Meier survival curves were used to analyse PRCT and DRCT.

RESULTS

Among 87 cracked teeth, 66 were molars, 19 premolars and 2 incisors. Fifty-two were DRCT, 35 were PRCT, 46 had a periodontal probing defect. Patients were followed up for a mean of 66.9 months (standard deviation 44.6, min 1 to max 172). Lack of probing depth was a significant protective factor against extraction (odds ratio [OR] 0.027, 95% confidence interval [CI] 0.003-0.27, p < .05), whereas further bone loss (OR 10.63, 95% CI 2.08-54.36, p < .05) was a risk factor for extraction. More than 50% of teeth treated with the adhesive protocol were functional (46 of 87 teeth [χ² test], p < .05) at 5-year follow-up. Among the PRCT group, a 78% survival rate at 5 years was found, while among the DRCT group, a 58% survival rate was found.

CONCLUSION

Composite resin restorations resulted in tooth survival in >50% of patients; 85.4% of PRCT and 61.5% of DRCT were functional after 5 years of follow-up.

In vivo detection of vertical root fractures in endodontically treated teeth: Accuracy of cone-beam computed tomography and assessment of potential predictor variables

Background

This study aimed: (a) to determine the diagnostic performance of cone-beam computed tomography (CBCT) for detection of vertical root fractures (VRFs); (b) to evaluate the predictive value of diagnostic criteria regarding the definition of VRFs; and (c) to examine the robustness of the association of patient-, tooth-, and treatment-related variables with VRFs.

Material and Methods

130 root-filled teeth with signs/symptoms of VRFs underwent clinical and CBCT assessments. Definite diagnosis of VRF was confirmed by endodontic microsurgical (EMS) exploration. Determination of diagnostic performance of CBCT was based on standard algorithms derived from two-way contingency table analysis. Predictive value of diagnostic criteria and the association between predictor variables with VRFs were analyzed using logistic regression models.

Results

VRFs were detected during EMS in 50% of the teeth. Based on the finding of fracture lines on CBCT scans, sensitivity, specificity, and accuracy were 86.2%, 13.8%, and 50%, respectively. Teeth having more than three diagnostic criteria present had significant higher odds for VRF diagnosis. After logistic regression analysis, parafunctional habits, one-canal roots, excessive root canal enlargement, and absence of intra-radicular posts remained as robust predictor variables of VRFs.

Conclusions

Although the sensitivity of CBCT for VRFs detection is high, the risk of false-positive results related to its low specificity makes that all suspected cases must be confirmed by surgical exploration. VRFs cannot be reliably diagnosed by isolated clinical signs/symptoms; instead those teeth possessing more than three diagnostic criteria might be considered practically pathognomonic. The parafunctional habits, one-canal roots, excessive root canal enlargement, and the absence of intra-radicular posts may act strongly/independently for the occurrence of VRFs in endodontically treated teeth.

Key words:Cone-beam computed tomography, diagnostic accuracy, diagnostic surgery, predictor variables, root canal treatment, vertical root fracture.

Occurrence of Vertical Root Fractures after Apical Surgery: A Retrospective Analysis

INTRODUCTION

Vertical root fractures (VRFs) are among the most frequent causes of tooth loss, mainly of endodontically treated teeth. However, very few data is available about the occurrence of VRFs following apical surgery.

METHODS

Patient charts from 864 patients with 1058 teeth treated with apical surgery (September 1999 to December 2018) were retrospectively evaluated, if a VRF had occurred after surgery. The following, possibly influencing factors were analyzed: sex and age, type of treated tooth, primary versus resurgery, technique of root-end preparation, and timepoint of VRF diagnosis. Endpoints were either tooth extraction or the last follow-up.

RESULTS

The study cohort (55% women, 45% men) had a mean age of 52.00 ± 13.97 years (range 9-93 years). The overall rate of VRFs after apical surgery was 4% (42 of 1058 teeth). Among these 42 teeth, 33.3% were mandibular first molars and 26.2% were maxillary second premolars. The most frequently affected root was the mesial root of mandibular first molars (28.6%). With regard to the study parameters, significant differences of VRF rates were observed only for the type of tooth treated.

CONCLUSIONS

A low VRF rate of 4% was observed in this study. VRFs commonly occurred in maxillary premolars and mandibular molars, with the mesial root of mandibular first molars affected most frequently. This is in line with previous reports about VRFs in endodontically treated teeth without additional apical surgery.

Influence of Metal Post in Adjacent Teeth in the Detection of Vertical Root Fracture Using Cone-beam Computed Tomography with Different Acquisition Parameters

INTRODUCTION

The aim of the present study was to evaluate the detection of vertical root fracture (VRF) in the presence of adjacent teeth restored with a metal post and the influence of acquisition parameters (tube current and metal artifact reduction [MAR] algorithm) on this diagnostic task.

METHODS

Cone-beam computed tomographic images of 10 single-rooted teeth were acquired before and after the simulation of VRF. The acquisitions were set up to simulate different conditions regarding the presence of adjacent teeth restored with a metal post (control, 1 adjacent tooth, and both adjacent teeth), different tube currents (4, 8, and 10 mA), and the use of MAR (without MAR and with MAR). Images were assessed by 5 oral and maxillofacial radiologists using a 5-point scale for the presence of VRF. Diagnostic values were calculated and compared by 2-way analysis of variance (significance level of 5%).

RESULTS

The area under the receiver operating characteristic curve (Az) values for VRF detection were affected by the presence of adjacent teeth and the variation of milliamperes. For 4 mA, when both restored teeth were present, Az values were significantly lower than the control group (P ≤ .05). In the presence of both restored teeth, 8 mA presented significantly higher Az values compared with 4 mA (P ≤ .05).

CONCLUSIONS

The presence of both adjacent teeth restored with a metal post impairs VRF detection; however, an increase in tube current up to 8 mA may aid in this diagnostic task. Moreover, the MAR tool does not seem to be efficient in those cases.

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.

Analysis of clinical associated factors of vertical root fracture cases found in endodontic surgery

BACKGROUND/PURPOSE

Early diagnosis of vertical root fracture (VRF) has been a great challenge. Since there is no single specific etiology identified, prevention of VRFs in endodontically treated teeth is quite difficult. The study aimed to evaluate the clinical associated factors of VRFs.

MATERIALS AND METHODS

A retrospective observational study of medical charts was conducted in the Department of Endodontics of Taipei Medical University Hospital in Taiwan from January 2012 to July 2018. Logistic regression model was performed to determine the association between VRF and its clinical associated factors, inclusive of the tooth characteristics (age, gender and tooth type) and iatrogenic risk factors (history of root canal treatment, restoration and post).

RESULTS

A total of 359 teeth were included in the study. The prevalence of VRF on a tooth basis was 18.7%. The result showed that age of more than 50 years (adjusted OR = 3.20, 95% CI: 1.81-5.64, p < 0.001) had significant higher risk of VRFs than those of less than 50 years. The subjects of molars (adjusted OR = 4.31; 95%CI = 2.24-8.27; P value < 0.001) and premolars (adjusted OR = 2.61; 95%CI = 1.16-5.86; P value = 0.021) had significant higher risk of VRFs than those of incisors. However, other variables such as gender, history of root canal treatment, restoration and post had no significant association with the VRF.

CONCLUSION

Age and tooth type are significant clinical associated factors of VRF. In the presence of these factors as well as predominant diagnostic factors, clinical practitioners should be aware of the possible diagnosis of VRFs.

Tooth Survival after Surgical or Nonsurgical Endodontic Retreatment: Long-term Follow-up of a Randomized Clinical Trial

INTRODUCTION

The aim of the study was to determine long-term tooth survival after endodontic retreatment and whether the presence of intraradicular posts influences the outcome.

METHODS

Ninety-five teeth were randomly assigned to surgical or nonsurgical endodontic retreatment. Forty-seven teeth in 45 patients were treated by conventional endodontic surgery and 48 teeth (47 patients) by nonsurgical retreatment, including the removal of intraradicular posts in 37 (77%). The outcome was tooth survival; follow-up continued until the tooth had been extracted, at least 10 years had elapsed since retreatment, the patient declined further follow-up, or the patient died. The Fisher exact test was used to analyze differences between the groups.

RESULTS

The median follow-up time was 10.1 years (range, 0.0-15.6 years). The overall survival rate was 76%, with no significant differences in long-term tooth survival between retreatment methods or the presence of an intraradicular post. The reasons for tooth extraction were related to the retreatment method. Vertical root fractures were significantly more frequent in the nonsurgical group when retreatment included post removal (P = .036).

CONCLUSIONS

There was no significant difference in long-term tooth survival after surgical or nonsurgical retreatment. The presence of intraradicular posts did not affect long-term tooth survival, but for teeth with posts, those retreated nonsurgically were more frequently extracted because of vertical root fractures than those retreated surgically (P = .036). The major limitations of the study were a smaller sample size and the use of outmoded retreatment techniques.

Diagnosis and Managment of Maxillary Incisor with Vertical Root Fracture: A Clinical Report with Three-Year Follow-Up

According to the American Association of Endodontists, "a 'true' vertical root fracture is defined as a complete or incomplete fracture initiated from the root at any level, usually directed buccolingually." Vertical root fracture (VRF) usually starts from an internal dentinal crack and develops over time, due to masticatory forces and occlusal loads. When they occur in teeth, those types of fractures can present difficulties in diagnosis, and there are however many clinic and radiographical signs which can guide clinicians to the existence of the fracture. Prognosis, most often, is hopeless, and differential diagnosis from other etiologies may be difficult sometimes. In this paper, we present a case of VRF diagnosed after surgical exploration; the enlarged fracture line was filled with a fluid resin. A 36-month clinical and radiological follow-up showed an asymptomatic tooth, reduction of the periodontal probing depth from 7 mm prior to treatment to 4 mm with no signs of ankylosis. In this work, the diagnosis and treatment alternatives of vertical root fracture were discussed through the presented clinical case.

An Automatic Segmentation and Classification Framework Based on PCNN Model for Single Tooth in MicroCT Images

Accurate segmentation and classification of different anatomical structures of teeth from medical images plays an essential role in many clinical applications. Usually, the anatomical structures of teeth are manually labelled by experienced clinical doctors, which is time consuming. However, automatic segmentation and classification is a challenging task because the anatomical structures and surroundings of the tooth in medical images are rather complex. Therefore, in this paper, we propose an effective framework which is designed to segment the tooth with a Selective Binary and Gaussian Filtering Regularized Level Set (GFRLS) method improved by fully utilizing three dimensional (3D) information, and classify the tooth by employing unsupervised learning Pulse Coupled Neural Networks (PCNN) model. In order to evaluate the proposed method, the experiments are conducted on the different datasets of mandibular molars and the experimental results show that our method can achieve better accuracy and robustness compared to other four state of the art clustering methods.