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

Risk factors for and clinical presentations indicative of vertical root fracture in endodontically treated teeth - a systematic review and meta-analysis

INTRODUCTION

The aim of this study was to identify specific clinical signs or symptoms and potential risk factors which are most likely associated with the presence of a vertical root fracture (VRF) in endodontically treated teeth (ETT).

METHODS

Electronic databases (MEDLINE via PubMed, EMBASE via Ovid, Scopus, and Web of Science) were searched by two reviewers in October 2022 for clinical studies, in which at least either the clinical presentation or potential risk factors associated with a VRF were assessed. Risk of bias was assessed using the Newcastle-Ottawa scale. Meta-analyses of odds ratios (ORs) were performed separately for several signs or symptoms and risk factors.

RESULTS

Fourteen sources reporting on 2,875 teeth (489 with VRF and 2,388 without VRF) were included in the meta-analyses. Regarding the clinical presentation, the presence of sinus tracts (OR=4.87; 95%-CI: 1.58-15.0), increased periodontal probing depths (OR=13.24; 95%-CI: 5.44-32.22), swelling/abscess (OR=2.86; 95%-CI: 1.74-4.70), and tenderness to percussion (OR=1.74; 95% CI: 1.18-2.61) were significantly associated with the presence of a VRF (P_adj. value<.05). None of the assessed risk factors (sex, type of teeth, tooth location, posts, indirect restoration, apical extension of the root canal filling), were found to be significantly associated with the presence of a VRF (P_adj. value>.05).

CONCLUSIONS

Four clinical presentations were identified to be the most significant signs or symptoms for a VRF in ETT: presence of sinus tracts, increased probing depths, swelling/abscess, tenderness to percussion. None of the assessed risk factors pointed out to be significantly associated with a VRF.

REGISTRATION

CRD42022354108 (PROSPERO).

Diagnostic efficacy of cone-beam computed tomography for detection of vertical root fractures in endodontically treated teeth: a systematic review

BACKGROUND

Vertical root fractures (VRFs) sometimes occur in endodontically treated teeth. They have a difficult diagnosis and a dismal result. The objective of this review was to evaluate the diagnostic performance of cone-beam computed tomography (CBCT) for detecting VRFs in teeth that had undergone endodontic treatment.

METHODS

Literature was reviewed from Web of Science, PubMed, Cochrane Review, SCOPUS, and Embase databases between 2000 and 2022. The searched keywords included "endodontically treated teeth," "cone-beam computed tomography," "CBCT," "tooth fracture," "vertical root fracture," "VRF," "accuracy," "sensitivity," and "specificity." Only articles in the English language were included. The final analysis included 20 papers that satisfied the eligibility requirements.

RESULTS

The overall mean ± SD values (%) for the diagnostic sensitivity and specificity of CBCT for detection of VRFs in endodontically treated teeth in the presence of root-filling materials without an intracanal post were 71.50 ± 22.19 and 75.64 ± 19.41, respectively. The overall mean (SD) value (%) for the sensitivity of CBCT for the detection of VRFs in the presence of root-filling materials and intracanal posts was 72.76 (18.73), while the mean (SD) specificity was 75.44 (18.26). The accuracy of CBCT (mean ± SD) was 78.47 ± 17.19% and 74.02 ± 10.64%, respectively, for teeth without intracanal posts and those with posts.

CONCLUSIONS

Further clinical research is needed to validate the optimum efficiency of CBCT as a diagnostic technique for detecting VRFs in teeth that have had endodontic treatment, given the low sensitivity, significant heterogeneity of studies, and lack of in-vivo studies on the subject.

Influence of the technical parameters of CBCT image acquisition on vertical root fracture diagnosis: a systematic review and meta-analysis

OBJECTIVES

To evaluate the influence of image acquisition parameters (voxel, FOV, kVp, mA) on the accuracy of cone-beam computed tomography (CBCT) in detecting vertical root fracture (VRF).

MATERIAL AND METHODS

Searches were performed in 6 main databases and the gray literature, without restrictions of language or date. Observational clinical studies (OCS) and in vitro-extracted teeth (IV) studies were considered eligible for inclusion when investigating the accuracy (sensitivity, specificity) of CBCT in detecting VRF in human teeth. The risk of bias was assessed using QUADAS-2, and a meta-analysis was performed using Review Manager v5.4 software and Jamovi software v1.6.

RESULTS

A total of 60 out of 132 articles was included after fulfilling the eligibility criteria. Of these, 54 were IV studies while 6 were OCS. In the IV studies, it was seen that smaller FOV sizes tended to present higher accuracy values. The meta-analysis of the 6 OCS showed that the overall sensitivity and specificity values for 0.08 mm and 0.1 mm voxels were greater (0.84 and 0.79, respectively) than the sensitivity and specificity values for 0.125 mm and 0.2 mm voxels (0.70 and 0.55, respectively).

CONCLUSIONS

Despite the uncertain risk of bias found for the IV and OCS studies, smaller voxel and FOV sizes seem to provide more accurate VRF detection values when using CBCT.

CLINICAL RELEVANCE

This information is crucial for supporting the clinician when prescribing CBCT in cases of a clinical suspicion of VRF, and contributes to the personalization of the CBCT prescription, thereby ensuring greater accuracy in the VRF diagnosis. Registration This protocol was registered at the PROSPERO database (International Prospective Register of Systematic Review) under registration number CRD42020210118.

Development and validation of a method for creating incomplete vertical root fracture in extracted teeth

The present study reported a method for inducing incomplete root fracture in human extracted teeth for the purpose of evaluating the merits of different diagnostic imaging techniques. Thirty-five single-rooted teeth were inspected under magnification and transillumination to exclude previously fractured teeth. Tooth crowns were removed, and the root canals were prepared up to the ProTaper Next X4 (40.06) file. Each root was lined with wax and embedded in a polystyrene resin block. The setup was attached to a universal testing machine for pressing a customized conical wedge (diameter at tip: 0.6 mm; taper: 0.2 mm/mm) into the instrumented canal with a 2 kN load at 5 mm/min. The machine was programmed to stop after a sudden 10% drop in loading force. Each specimen was removed from the resin block and inspected under × 20 magnification and transillumination to identify the fracture characteristics (pattern, surfaces and root-third affected). The gap width of each specimen was measured at different locations along the fracture line. The protocol induced incomplete vertical root fractures in all specimens. Fracture widths were < 100 μm in all specimens (mean gap width: 34.9 μm). The proposed methodology was successful in inducing incomplete vertical root fractures with characteristics that resemble the clinical presentation of these conditions. The method is easy to execute, highly reproducible and helps to minimize bias in laboratory studies that aims to mimic vertical root fractures.

A micro-CT analysis of radicular dentine thickness in mandibular first premolars presenting C-shaped root canals: Identification of potential danger zones

AIM

To describe the radicular dentine thickness in mandibular first premolars presenting C-shaped root canals, in order to identify the canal walls with less thickness as potential danger zones. In addition, to describe the internal and external anatomical characteristics of these teeth and to associate them to the dentine thickness.

METHODOLOGY

A total of 70 mandibular first premolars presenting C-shaped root canals were examined. Their internal morphology was analyzed using Vertucci´s and Fan´s criteria, and their external morphology was analyzed using the ASUDAS score. Besides, the dentine thickness around the root canals was two/three-dimensionally determined at five root planes and quantified in the distal and the mesial aspects.

RESULTS

According to Fan´s, ASUDAS, and Vertucci´s classifications, the most common canal configurations were category C3, grade 3, and type V, respectively. In Vertucci's type III anatomy, the mesial root wall of the lingual canal showed significantly less dentine thickness than the distal wall in the middle plane (p = 0.031). Similarly, in Vertucci's type V anatomy, significantly less dentine thickness was observed in the mesial root wall of the buccal and lingual canals in the middle plane (p < 0.001) and the buccal canal in the middle-apical plane (p = 0.014) than the distal root wall of these canals. In teeth with ASUDAS grade 3 and 4 scores, significantly less dentine thickness was observed in the mesial in comparison with the distal root wall of these canals. These differences were demonstrated in the middle and middle-apical planes (p < 0.001) of grade 3 teeth and the middle-apical plane (p < 0.001) of grade 4 teeth. In these root planes, the Ver1-AS3 and VerV-AS3 combinations presented a 4-times greater risk of presenting walls with a critical dentine thickness of 0.6 mm (OR=4, p = 0.025) than the combinations Ver1-AS2, VerV-AS2, VerV-AS4, and VerIII-AS3.

CONCLUSIONS

The root canal system configuration of mandibular first premolars with C-shaped canals showed a wide range of anatomical variations. The lowest dentine thickness was located in the mesial wall of the canals in the middle and apical root thirds of Vertucci´s type III and V anatomies and in teeth with deep radicular grooves scored as ASUDAS grade 3 and 4. In the middle and middle-apical planes, the presence of the combinations Ver1-AS3 and VerV-AS3 showed a high risk of presenting a critical dentine thickness of 0.6 mm. Therefore, these root canal walls with less dentine thickness represent potential instrumentation danger zones in mandibular first premolars with C-shaped canals.

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.