Radiological diagnosis of periapical bone tissue lesions in endodontics: a systematic review

Evaluation of preoperative apical periodontitis, treatment indications, and methods in endodontically treated teeth: a retrospective study

BACKGROUND

This study evaluated the presence of preoperative apical periodontitis (AP) in endodontically treated teeth within a Turkish population, along with its causes, treatment methods, and the effectiveness of preventive and early intervention practices.

METHODS

A retrospective analysis was conducted on 1,440 teeth from 1,055 patients treated at Van Yüzüncü Yıl University between 2021 and 2023. Preoperative panoramic and periapical radiographs and postoperative periapical radiographs were examined. Data recorded included patient demographics, treated tooth location, presence of preoperative AP, coronal restorations, reasons for treatment, treatment methods, and number of missing and endodontically treated teeth. Statistical analyses were performed using Chi-Square, Mann-Whitney U, Kruskal-Wallis, and Spearman correlation tests.

RESULTS

The overall incidence of AP was reported as 28.7%. It was more frequently observed in the mandible than in the maxilla and in incisors compared to other tooth groups (p < 0.001). Caries was the primary reason for treatment in molars (81.5%), while periodontal disease was more common in incisors (p < 0.001). As age increased, the number of endodontically treated and missing teeth also rose (p = 0.019; p < 0.001). Teeth with crowns had a lower AP rate, while retreatments due to periodontal disease or previous root canal failures showed higher AP rates (p < 0.001).

CONCLUSIONS

The high AP rate and the predominance of caries and periodontal disease as treatment causes indicate insufficient application of preventive and early treatments. AP prevalence varied by jaw location, tooth group, coronal restoration and treatment method. This study provides epidemiological data on endodontically treated teeth and their association with AP. These findings emphasize the importance of early diagnosis, preventive measures, and effective treatment planning in preserving tooth survival.

Apical periodontitis in inflammatory bowel disease: a meta-analysis at patient and tooth level

Apical periodontitis (AP) is the local inflammation of periapical tissues originating from the dental pulp disease. Cumulative evidence suggests a link between oral and gastro-intestinal systems in both health and disease. In this context, the relationship between AP and inflammatory bowel diseases (IBDs) has not yet been elucidated. The aims of this systematic review and meta-analysis were to describe the prevalence of AP in patients with IBDs and evaluate the potential association between AP and IBDs. Electronic (Embase, PubMed, Scopus, Web of Science) and manual literature searches were conducted from inception to 31 October, 2023 (updated in August, 2024). Strict inclusion criteria were applied to identify observational and experimental clinical studies on AP in IBDs patients. The bias risk was assessed using the Joanna Briggs Institute critical appraisal tools and a biases' report selected from the Oxford Centre for Evidence Based Medicine Catalogue of Bias. A meta-analysis was performed to determine the pooled prevalence and risk of AP at individual and tooth level and the quality of evidence was assessed by the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. The search strategy identified 82 articles with 5 studies included (657 subjects, 7,142 teeth). The overall proportion of AP was 58% at patient level (95% CI = 37%-78%, I 2 = 95.3%) and 7% at tooth level (95% CI = 2%-15%; I 2 = 99.2%). AP was prevalent in IBDs subjects than in healthy controls, both at patient and tooth level. The pooled OR was 1.57 (95% CI = 1.04-2.35; P = 0.038; I 2 = 20%) at patient level, and 1.91 (95% CI = 1.16-3.15; P = 0.011; I 2 = 82%) at tooth level. A potential association between AP and IBDs is plausible, although the quality evidence was low to very low. Longitudinal and experimental studies should be conducted to better understand the relationship between these two conditions and explore any potential causative factors.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=411038, PROSPERO (CRD42023411038).

Radicular Cysts and Periapical Granulomas: Data Documentation for 696 Cases and Findings on Fibrosis, and Porphyromonas gingivalis and Fusobacterium nucleatum in These Lesions

OBJECTIVE

The objective of our study was to re-evaluate periapical lesions, including radicular cysts (RCs) and periapical granulomas (PGs) for locations, histopathological features, and degree of fibrosis in relation to the inflammatory response. In addition, we examined the presence of Porphyromonas gingivalis (Pg) and Fusobacterium nucleatum (Fn) since both are widely recognized pathogens in periodontal infections.

METHODS

We re-evaluated samples of RCs and PGs (n = 728) and collected data for analyses by IBM's SPSS Statistics. Among these samples, we stained 93 samples to determine the immunoexpression of Pg and Fn. For immunostaining, we used Gingipain R1 antibody for Pg and Rabbit anti-Fn antibody for Fn.

RESULTS

Fibrosis is associated with mild inflammation. We found a significant positive correlation between Pg and Fn. Thus, these pathogens are likely to occur together in periapical inflammatory lesions. We additionally noted that these periodontopathic pathogens are more likely to be present in RCs than in PGs.

CONCLUSIONS

Asymptomatic radiologically diagnosed periapical lesions may not necessarily need root canal retreatment in healthy patients since these lesions may represent scar tissue rather than active apical periodontitis. Clinical and radiological follow-up is still needed. Yet, periapical lesions, especially cysts, may contain dystopic periodontopathic pathogens, and Pg and Fn often occur together in periapical lesions.

Comparison of periapical parallel radiography with cbct with different field of views (FOV) for the detection of periapical lesions

Background

Chronic apical periodontitis (AP) may influence the outcome of root canal treatment. Thus, it is important to diagnose AP using the best method available. This research was done to compare the diagnostic accuracy of parallel periapical radiography (PR) and different field of views (FOVs) of cone-beam computed tomography (CBCT).

Materials and Methods

This ex vivo study was done on six human mandibles. After extraction of the teeth, periapical lesions with different sizes were prepared randomly by drilling a hole at the base of the socket using a bur. From among 67 sockets, 21 sockets had no lesion (control); then, all mandibles were scanned by CBCT with different FOVs and paralleling periapical technique radiography. The images were assessed by two examiners. The quantitative data were analyzed by intraclass correlation coefficient (ICC) and the qualitative data were analyzed by McNemar's test (α = 0.05). Sensitivity, specificity, and accuracy were calculated. Inter-observer agreement was assessed using kappa statistics for qualitative data and ICC for quantitative data.

Results

The quantitative scores were compared with the gold standard using ICC, which showed maximum agreement for the dental FOV of CBCT (93.3) and minimum agreement for PR (62.5) (P < 0.001). For qualitative data, maximum agreement was found for the dental FOV of CBCT (97.1%), and minimum agreement was reported for PR (59.7%). Kappa values were variable between 0.271 and 0.924 (P < 0.001). Maximum sensitivity was found for the dental FOV of CBCT (96%) and minimum sensitivity was observed for PR (51%). The inter-observer agreement was 0.922 for qualitative data and 0.90 for quantitative data (P < 0.001). There were no significant differences between CBCT with different FOVs and defect sizes (gold standard) while we found significant differences for periapical by defect sizes.

Conclusion

CBCT with dental FOV presents the highest sensitivity and diagnostic accuracy for detection and characterization of simulated AP.

Endodontic Treatment Outcomes in Cone Beam Computed Tomography Images-Assessment of the Diagnostic Accuracy of AI

Background/Objectives: The aim of this study was to assess the diagnostic accuracy of the AI-driven platform Diagnocat for evaluating endodontic treatment outcomes using cone beam computed tomography (CBCT) images. Methods: A total of 55 consecutive patients (15 males and 40 females, aged 12-70 years) referred for CBCT imaging were included. CBCT images were analyzed using Diagnocat's AI platform, which assessed parameters such as the probability of filling, adequate obturation, adequate density, overfilling, voids in filling, short filling, and root canal number. The images were also evaluated by two experienced human readers. Diagnostic accuracy metrics (accuracy, precision, recall, and F1 score) were assessed and compared to the readers' consensus, which served as the reference standard. Results: The AI platform demonstrated high diagnostic accuracy for most parameters, with perfect scores for the probability of filling (accuracy, precision, recall, F1 = 100%). Adequate obturation showed moderate performance (accuracy = 84.1%, precision = 66.7%, recall = 92.3%, and F1 = 77.4%). Adequate density (accuracy = 95.5%, precision, recall, and F1 = 97.2%), overfilling (accuracy = 95.5%, precision = 86.7%, recall = 100%, and F1 = 92.9%), and short fillings (accuracy = 95.5%, precision = 100%, recall = 86.7%, and F1 = 92.9%) also exhibited strong performance. The performance of AI for voids in filling detection (accuracy = 88.6%, precision = 88.9%, recall = 66.7%, and F1 = 76.2%) highlighted areas for improvement. Conclusions: The AI platform Diagnocat showed high diagnostic accuracy in evaluating endodontic treatment outcomes using CBCT images, indicating its potential as a valuable tool in dental radiology.

Artificial Intelligence and Its Application in Endodontics: A Review

AIM AND BACKGROUND

Artificial intelligence (AI) since it was introduced into dentistry, has become an important and valuable tool in many fields. It was applied in different specialties with different uses, for example, in diagnosis of oral cancer, periodontal disease and dental caries, and in the treatment planning and predicting the outcome of orthognathic surgeries. The aim of this comprehensive review is to report on the application and performance of AI models designed for application in the field of endodontics.

MATERIALS AND METHODS

PubMed, Web of Science, and Google Scholar were searched to collect the most relevant articles using terms, such as AI, endodontics, and dentistry. This review included 56 papers related to AI and its application in endodontics.

RESULT

The applications of AI were in detecting and diagnosing periapical lesions, assessing root fractures, working length determination, prediction for postoperative pain, studying root canal anatomy and decision-making in endodontics for retreatment. The accuracy of AI in performing these tasks can reach up to 90%.

CONCLUSION

Artificial intelligence has valuable applications in the field of modern endodontics with promising results. Larger and multicenter data sets can give external validity to the AI models.

CLINICAL SIGNIFICANCE

In the field of dentistry, AI models are specifically crafted to contribute to the diagnosis of oral diseases, ranging from common issues such as dental caries to more complex conditions like periodontal diseases and oral cancer. AI models can help in diagnosis, treatment planning, and in patient management in endodontics. Along with the modern tools like cone-beam computed tomography (CBCT), AI can be a valuable aid to the clinician. How to cite this article: Ahmed ZH, Almuharib AM, Abdulkarim AA, et al. Artificial Intelligence and Its Application in Endodontics: A Review. J Contemp Dent Pract 2023;24(11):912-917.

Factors that affect the outcomes of root canal treatment and retreatment-A reframing of the principles

This paper undertakes a broad and comprehensive synthesis of relevant clinical, biological, biomechanical, technical and healthcare services data to understand the factors affecting outcomes of periapical healing after root canal (re)treatment. The medical and dental evidence-based era (1980-present) is contextualized with the earlier evidence drive in endodontics (1911-1940) triggered by the focal infection era. The current evidence-based approach has a sharper focus on evidence quality and derivation of practice guidelines. Contrary views question whether guideline-driven, or expertise-development-driven endeavours would best serve outcome improvement in society. The endodontic discipline functions in a broad healthcare framework and sustains industrial, economic and trend pressures that may be deemed to influence outcomes. The nature of root canal treatment and the challenges in determining the factors that affect its outcomes is discussed. The factors potentially affecting periapical healing after root canal treatment are classified into pre-operative, intra-operative and postoperative groups. These categories subsume multiple elements with interactive influences, creating a complex picture, further confounded by some apparently surprising, counter-intuitive and contradictory findings. The technical versus biological conundrum in root canal treatment continues to cause cognitive dissonance. However, due reflection and cross-discipline-synthesis resolve the apparent data conflicts into a very simple, consistent and plausible picture of how root canal treatment works and the key factors that affect periapical healing. Root canal retreatment is considered mainly in the context of its differences from primary treatment as the majority of factors influencing outcomes are common to both. The exceptional difference is that retreatments have a proportionately reduced probability of healing by virtue of compromised apical root canal ramification access or modified host/infection interactions. Root canal (re)treatment outcomes are dominantly influenced by the nature of prior dynamic host/infection interaction (pre-operative patient factors) and how the direction of this dynamic is influenced by two factors: (1) the active efficacy of the operators' root canal treatment protocol to sustain a microbial ecological shift (intra-operative treatment factors) and dampen periapical inflammation; and (2) the passive ability of the functional tooth (and its restoration margin) to maintain its integrity to resist infection reversal (postoperative restorative factors).

Clinical decision making of post-treatment disease

Root-filled teeth presenting with signs of post-treatment disease is a common finding in virtually every dental practice. There is both empirical and experimental evidence that, as long as the condition is asymptomatic, it is often left untreated. Professional judgements and decision making in endodontics as in any medical discipline are based on qualified estimations of the probability and the value of relevant outcomes. In this paper we describe various aspects of clinical decision making in general, from a descriptive as well as a normative point of view, but with a particular focus on the condition of the root-filled tooth with post-treatment disease. We review how attention to various types of uncertainties are relevant for the decision-making process. Additionally, we discuss the nature of value judgements and different concepts of health and disease which are important for understanding the complexity of the clinical decision-making process. We also refer to a set of principal rules that can guide the clinician's decision making in every-day practice in front of a case with endodontic post-treatment disease. Finally, we provide some aspects on the sometime cumbersome decision whether to go for a non-surgical or surgical method, whenever a decision on retreatment has been made.

Current status of cone-beam computed tomography teaching in Brazilian undergraduate endodontic programs - A web-based survey

PURPOSES

This study aimed to assess the current status of cone-beam computed tomography (CBCT) education in Brazilian undergraduate Endodontic programs.

METHODS

One hundred program directors were emailed. The questionnaire asked whether the CBCT topic was included in the program, the availability of a CBCT machine, and, the total length of the dental program. For the group that does not teach, seven questions discussed the reasons for not teaching and whether another subject included this topic. For the programs that included CBCT, seven questions discussed the number of hours included, and the impression of the program directors with the quality of the teaching. The chi-square test was used for the correlation between the availability of the CBCT machine and the length of the dental program with the inclusion of the topic.

RESULTS

Thirty-five program directors replied to the questionnaire. Twenty-six (74.3%) reported that the topic of CBCT is not included in their programs. There was no impact of the availability of a CBCT machine on the inclusion of the topic (p > 0.05). The increased length of the dental program decreased the inclusion of the topic (p < 0.05). Fifty percent of the directors replied that lack of time is the reason for not including the topic. Among the programs that include CBCT, the majority (55.6%) deliver 3-5 h of lectures. The practical activities range from 1 to 5 h or more. The majority (77.8%) of the directors are satisfied with the content delivered and 44.4% understand that the students are competent in the interpretation of CBCT images.

CONCLUSIONS

The majority of the Endodontic undergraduate programs in Brazil do not include CBCT in the program. The availability of a CBCT machine does not impact the inclusion of the topic, the increased duration of the dental program decreases the inclusion of the CBCT topic.

The Changes in Size of Periapical Lesions after Root Canal Treatments Assessed by Digital Periapical Radiography and Cone-Beam Computed Tomography: A 2-Years Prospective Clinical Study

Background and Objectives: There is limited information regarding comparison of long-term dynamics of periapical bone destruction estimated by digital periapical radiography (DPR) and by cone-beam computed tomography (CBCT). This study aimed to compare the radiographically assessed periapical changes of endodontically treated teeth over 2 years of follow-up and to analyse disagreements in periapical lesion size estimates around the same roots using DPR and CBCT. Materials and Methods: A total of 176 endodontically treated teeth, of 128 patients with apical periodontitis, were assessed by DPR and CBCT, at baseline and after 2 years. All periapical radiolucencies were categorised by severity (S0, S1, S2, S3) concerning their size. Descriptive statistics were used to report distribution of the radiolucencies at baseline and at follow-up, and their size transitions over 2 years. Site-specific comparison of the radiolucencies identified by two methods was performed using Z test and Pearson’s chi-square test. Results: majority of the detected radiolucencies were scored as S0: 65% and 68% at baseline; 89% and 83% at follow-up, by DPR and CBCT, respectively. Site-specific score comparison showed that disagreements comprised 18% and 20% of the total number of radiolucencies detected by DPR and CBCT, respectively. There were more disagreements between DPR and CBCT within categories S1 and S2 + S3 compared to S0: at baseline, they comprised 17–33% and after two years 62–95% of all detected radiolucencies within the category. 65% of non-matching score transitions over two years occurred between S0 and S1. The CBCT-based evaluation resulted in negative treatment outcomes for 10 more root canals than the DPR-based result. Conclusions: Most remarkable disagreement between DPR and CBCT recordings was observed within the radiolucency categories S2 and S3. However, the diagnostic accuracy of both radiographic methods was questionable as it resulted in a high proportion of non-matching S0-S1 lesion transitions over 2 years.

Artificial Intelligence in Dentistry: Past, Present, and Future

Artificial intelligence (AI) has remarkably increased its presence and significance in a wide range of sectors, including dentistry. It can mimic the intelligence of humans to undertake complex predictions and decision-making in the healthcare sector, particularly in endodontics. The models of AI, such as convolutional neural networks and/or artificial neural networks, have shown a variety of applications in endodontics, including studying the anatomy of the root canal system, forecasting the viability of stem cells of the dental pulp, measuring working lengths, pinpointing root fractures and periapical lesions and forecasting the success of retreatment procedures. Future applications of this technology were considered in relation to scheduling, patient care, drug-drug interactions, prognostic diagnosis, and robotic endodontic surgery. In endodontics, in terms of disease detection, evaluation, and prediction, AI has demonstrated accuracy and precision. AI can aid in the advancement of endodontic diagnosis and therapy, which can enhance endodontic treatment results. However, before incorporating AI models into routine clinical operations, it is still important to further certify the cost-effectiveness, dependability, and applicability of these models.

Linking Dentistry and Chronic Inflammatory Autoimmune Diseases – Can Oral and Jawbone Stressors Affect Systemic Symptoms of Atopic Dermatitis? A Case Report

Background

This case report demonstrates the value of ultrasound measurements, and immunological and toxicological diagnostics in addition to current x-ray imaging procedures to diagnose hidden oral and maxillofacial infections. Using a clear scheme shows the procedure of the authors’ steps. The positive impact on the patient’s dermatological clinical picture is shown. Functional regeneration using metal-free ceramic implants and autologous bone augmentation is demonstrated. After a healing period, a postoperative control took place.

Question

Are chronic inflammatory and chronic toxic stressors from the oral region affecting the patient’s state of health and dermatological symptoms?

Patients and Methods

A 52 year old female suffering from neurodermatitis, who had been therapy-resistant for several years, was rehabilitated by oral surgery and prosthetics. Radiological examinations with orthopantomogram (OPG) and three-dimensional imaging (DVT/CBCT) were inconclusive for possible jawbone inflammatory sites. Immunological, toxicological diagnostics and trans-alveolar bone densitometry with ultrasound (TAU), were able to show immunological and toxicological stressors and areas of reduced bone density. Bone densitometry with ultrasound raised the suspicion of silent inflammations in the jawbone with potentially increased cytokine levels.

Results

For the patient incompatible materials, teeth with increased toxin exposure and surrounding softened, fatty, ischaemic bone was removed. Histologies and cytokine profiles were obtained. The resulting defects were functionally regenerated using ceramic implants and autologous augmentation. The cytokine profiles showed significantly elevated RANTES/CCL5, confirming the need for surgical intervention. The patient’s atopic dermatitis improved significantly in this case.

Summary

Individualized immunological and toxicological diagnostics and trans-alveolar bone density bone densitometry with ultrasound (TAU) identified immunological and toxicological stressors as well as reduced bone density with increased cytokine levels. A therapy-resistant neurodermatitis improved significantly after treatment.

Conclusion

This case report illustrates the need for patient-specific and individualized examinations that link dentistry more closely with other medical conditions in order to clarify possible interactions.

Quantitative Analysis of Cone-Beam Computed Tomography Artifacts Induced by Nonmetallic Root Canal Filling Materials Using Different Fields of View: In Vitro Study

Cone-beam computed tomography (CBCT) imaging artifacts can hinder accurate diagnosis of several conditions. The aim of this study was to quantify CBCT artifacts created by nonmetallic root canal filling materials using two fields of view (FOV). Root canals of twenty extracted maxillary central incisors (n = 20) were instrumented and randomly divided into four equal groups: canals in Group 1 were filled with gutta-percha, canals in Group 2 with mineral trioxide aggregate (MTA) and gutta-percha, canals in Group 3 with gutta-percha and glass-fiber posts, and canals in Group 4 with MTA and glass-fiber posts. Each tooth was mounted on a silicon block and scanned three times using a CBCT machine, first with a prefilling scan (control) and then with postfilling scans, using two different FOV (40∗50 mm and 80∗50 mm). Imaging software was used to measure grayscale pixel values of canal cross sections. Data were analyzed using t-test and paired t-test statistical tests, with statistical significance set at p ≤ 0.05. Dentin at the apical and middle third of the teeth showed a significant decrease in minimum grayscale values in association with gutta-percha (p = 0.027, p = 0.034). However, a wide 80∗50 FOV showed a significant increase in maximum grayscale values of coronal (p = 0.048) and apical dentin (p = 0.049). Glass-fiber posts in middle third cross sections also corresponded to an increase in maximum grayscale values (p = 0.018). Gutta-percha produced dark band artifacts in the root's middle and apical thirds, whereas white streak artifacts were produced by gutta-percha in the coronal third and glass-fiber posts in the coronal and middle thirds when imaged with a wider FOV. A smaller FOV is therefore recommended for CBCT imaging, as it produces fewer artifacts.

Comparison of the diagnostic efficacy of 2D radiography and cone beam computed tomography in persistent apical periodontal disease: A PRISMA-DTA systematic review and meta-analysis

OBJECTIVE

The objective of this study was to answer the question: Do conventional radiographs (periapical/panoramic) afford better diagnostic outcomes than cone beam computed tomography (CBCT) as a complement for clinical diagnosis of apical lesions with persistent apical periodontitis or disease after root canal treatment?

STUDY DESIGN

Five electronic databases were searched and provided information to enable construction of a table to determine primary diagnostic measures and secondary parameters. The evidence was appraised with the Quality Assessment of Diagnostic Accuracy Studies tool and GRADEpro software.

RESULTS

Twenty-seven articles (9903 diagnostic images) were included. The pooled sensitivity, specificity, area under the receiver operating characteristic curve (AUC_ROC), positive predictive value, negative predictive value, negative likelihood ratio, and accuracy were 0.58, 1, 0.77, 1, 0.68, 0.45, and 0.79, respectively.

CONCLUSIONS

Moderate certainty evidence suggested that conventional radiographs showed poor sensitivity and excellent specificity but good diagnostic performance in terms of AUC_ROC and accuracy. Sensitivity, AUC_ROC, and negative likelihood ratio values could be reduced if the time elapsed to diagnosis after root canal treatment exceeded 5 years. The use of CBCT with a reduced field of view or a 2D radiographic technique should be weighed considering patient-specific and indication-oriented criteria as taking precedence over the therapeutic goal.

Ultrasound Imaging versus Radiographs in Differentiating Periapical Lesions: A Systematic Review

BACKGROUND

Ultrasonography is a non-invasive method of diagnosing periapical lesions while radiologic methods are more common. Periapical lesions due to endodontic infection are one of the most common causes of periapical radiolucency that need to be distinguished to help determine the course of treatment. This review aimed to examine the accuracy of ultrasound and compare it to radiographs in distinguishing these lesions in vivo.

METHODS

This review process followed the PRISMA guidelines. A literature search of databases (PubMed, Scopus, Embase, and Web of Science) was conducted without any restrictions on time. Articles available in English were included. The selection was done according to the inclusion and exclusion criteria. The QUADAS-2 tool was used to assess the quality of the studies.

RESULTS

The search provided a total of 87 articles, out of which, five were selected for the final review. In all the studies, ultrasound had higher accuracy in distinguishing periapical lesions. All the studies indicated a risk of bias, especially in patient selection.

CONCLUSION

Within limitations, the study indicates that ultrasound is a better diagnostic tool to distinguish periapical lesions compared to radiographs but further studies with well-designed, rigorous protocols and low risk of bias are needed to provide stronger evidence.

Evaluation of the accuracy values of cone-beam CT regarding apical periodontitis: a systematic review and meta-analysis

Specialists need to know how accurate and effective each radiographic procedure is, and which ones can provide better images for bone resorption around the apical periodontitis. Therefore, the researcher decided to conduct the present study with the aim of evaluate the accuracy values of cone-beam CT regarding apical periodontitis. The PubMed, Embase, ISI, Scopus, and Medicine have been used to search articles over the last 15 years between 2005 and December 2020. Meta-analysis data with 95% confidence interval (CI), Random effect model, and restricted maximum-likelihood methods were calculated. Random effects were used to deal with potential heterogeneity and I² showed heterogeneity. I² values above 50% signified moderate-to-high heterogeneity. The meta-analysis has been evaluated with the statistical software Stata/MP v.16 (The fastest version of Stata). One hundred and fifty-eight studies were selected to review the abstracts, six papers met these crucial criteria to do a systematic review and meta-analysis. Sensitivity and specificity of digital periapical radiography was 50% (ES 0.50; 95% CI 0.05, 0.95) and 83% (ES 0.83; 95% CI 0.52, 1.15), respectively. Sensitivity and specificity of cone-beam computed tomographic was 95% (ES 0.95; 95% CI 0.80, 1.00) and 90% (ES 0.90; 95% CI 0.78, 1.03), respectively. In conclusion, CBCT imaging reports values with excellent accuracy vs digital periapical radiography.

Artificial Intelligence in Endodontics: Current Applications and Future Directions

INTRODUCTION

Artificial intelligence (AI) has the potential to replicate human intelligence to perform prediction and complex decision making in health care and has significantly increased its presence and relevance in various tasks and applications in dentistry, especially endodontics. The aim of this review was to discuss the current endodontic applications of AI and potential future directions.

METHODS

Articles that have addressed the applications of AI in endodontics were evaluated for information pertinent to include in this narrative review.

RESULTS

AI models (eg, convolutional neural networks and/or artificial neural networks) have demonstrated various applications in endodontics such as studying root canal system anatomy, detecting periapical lesions and root fractures, determining working length measurements, predicting the viability of dental pulp stem cells, and predicting the success of retreatment procedures. The future of this technology was discussed in light of helping with scheduling, treating patients, drug-drug interactions, diagnosis with prognostic values, and robotic-assisted endodontic surgery.

CONCLUSIONS

AI demonstrated accuracy and precision in terms of detection, determination, and disease prediction in endodontics. AI can contribute to the improvement of diagnosis and treatment that can lead to an increase in the success of endodontic treatment outcomes. However, it is still necessary to further verify the reliability, applicability, and cost-effectiveness of AI models before transferring these models into day-to-day clinical practice.

Low-dose Multidetector Computed Tomographic and Cone-beam Computed Tomographic Protocols for Volumetric Measurement of Simulated Periapical Lesions

INTRODUCTION

The purpose of this study was to evaluate the accuracy of low-dose multidetector computed tomographic (LD-MDCT) imaging for the volumetric measurement of simulated periapical lesions.

METHODS

Eighteen monoradicular teeth were introduced in bone blocks, and periapical lesions were simulated at the periapical region of each tooth. All teeth were imaged using 4 acquisition protocols: large (dentoalveolar) field of view (FOV) cone-beam computed tomographic (CBCT) imaging (120 kV, 5 mA, and 0.2-mm voxel), small (dental) FOV CBCT imaging (90 kV, 10 mA, and 0.2-mm voxel), standard multidetector computed tomographic imaging (120 kV, 50 mA, and 0.62-mm voxel), and LD-MDCT imaging (120 kV, 10 mA, and 0.62-mm voxel). Tomographic images were evaluated by a single trained and calibrated examiner (intraclass correlation coefficient = 0.991) using ITK-SNAP segmentation software (University of Pennsylvania, Philadelphia, PA). The gold standard was obtained by the impressions of the lesions with regular fluid addition silicone and individual weighing using a precision analytical scale. Data were evaluated by the repeated measures analysis of variance test; the significance level was defined as P < .05.

RESULTS

No statistical differences (P > .05) were found among the groups regardless of the device, milliamperage, FOV, or voxel size.

CONCLUSIONS

LD-MDCT shows performance comparable with other standard reference methods for measuring the volume of periapical lesions and can be a useful and safe protocol in clinical situations in which CBCT imaging is not available, such as in cases of patients admitted to hospitals.

Effect of a formalin-based fixation method on bone mineral content in human ex-vivo specimens

OBJECTIVE

Histopathology of formalin-fixated human ex-vivo specimens may be used as reference standard for evaluation of diagnostic index tests like CBCT or MRI. The aim was to estimate changes in bone mineral content (BMC) over time in human ex-vivo bone specimens fixated in a formalin-based solution for 24 h followed by storage in an alcohol-based medium for six months, assessed by dual-energy X-ray absorptiometry (DXA).

METHODOLOGY

Bone specimens (n = 19) from human ex-vivo mandibles donated for science were included. BMC was measured by DXA before fixation (D₀), after 24 h of immersion fixation in a formalin-based solution (D₁), and hereafter every 30 days (M₁-M₆) during storage in a 30% ethanol-based storage medium for 6 months. Changes in BMC from D₀ to D₁ and from D₀ to M₆ were calculated and mean change in BMC estimated.

RESULTS

Mean change in BMC from D₀ to D₁ was -0.73% (95% CI -1.75%; 0.29%), and from D₀ to M₆ -1.19% (95% CI -2.14%; -0.23%).

CONCLUSIONS

No changes in BMC of ex-vivo human bone specimens were found after 24 h formalin-based immersion fixation. After six months storage in an ethanol-based medium, BMC mean loss of 1% was detected. In this range, changes in BMC are not clinically relevant.

Endodontic disease detection: digital periapical radiography versus cone-beam computed tomography-a systematic review

Purpose: To assess the comparative diagnostic performance of digital periapical (PA) radiography and cone-beam computed tomography (CBCT) imaging on endodontic disease detection and to provide study methodology and design recommendations for future studies comparing the diagnostic performance of imaging modalities on endodontic disease detection. Approach: A search of the Medline, Embase, Scopus, Web of Science, and the Cochrane Central Register of Controlled Trials databases was conducted. Studies that compared the performance of CBCT to digital PA radiography for detecting endodontic disease had an independent reference standard determining the presence of endodontic disease and conducted data analysis including either sensitivity, specificity, receiver operating characteristic (ROC) analysis or free response operating characteristic analysis were included. Of the 20,530 identified studies, only 3 fulfilled the inclusion criteria. Results: Most studies assessed for eligibility were excluded due to limitations and biases in study design-15 of 18 studies had no reference standard. Only one retrospective clinical study reported on the diagnostic performance of CBCT and showed a sensitivity of 86% and specificity of 26%. Two cadaver studies reported sensitivity ranging from 60% to 100%, specificity ranging from 79% to 100%, and an area under the ROC curve of 0.943 for CBCT. The reported sensitivity for digital PA radiography ranged from 27% to 60%, specificity was 99%, and the area under the ROC curve was 0.629. Conclusions: There is a lack of quality evidence and insufficient data to compare diagnostic performance of digital PA and CBCT imaging. This emphasizes the need for well-designed studies to inform clinicians about the relative diagnostic performance of these imaging modalities.

Two decades of research on CBCT imaging in DMFR - an appraisal of scientific evidence

OBJECTIVE

This article aims to appraise how scientific evidence related to CBCT has changed over the years, based on levels of evidence and diagnostic efficacy.

METHODS

A general search strategy was used in different databases (Pubmed, Embase, and Web of Science) to identify systematic reviews (SRs) on CBCT until November of 2020. The SRs included were divided according to different specialties of dentistry. A critical review of the articles was made, describing the level of evidence and efficacy.

RESULTS

In total, 75 articles were selected. There was an increase in the number of SRs on CBCT from 2014 onwards, as 83% of the SRs on this topic were published after 2013, and 72% between 2016 and to date. Twenty SRs (27%) performed meta-analysis. Only 28% of the SRs provided a detailed description of CBCT protocols. According to SR evidence, almost all specialties of dentistry have advanced concomitantly with the introduction of CBCT. The majority of SRs were related to clinical applications (level 2 of efficacy), followed by technical parameters (level 1 of efficacy). Only some CBCT models were mentioned in the SRs selected.

CONCLUSION

Over the course of 20 years, SRs related to CBCT applications for a broad range of dental specialties have been published, with the vast majority of studies at levels 1 and 2 of diagnostic efficacy. Not all CBCT models available on the market have been scientifically validated. At all times, one should remain cautious as such not to simply extrapolate in vitro results to the clinical setting. Also, considering the wide variety of CBCT devices and protocols, reported results should not be overstated or generalized, as outcomes often refer to specific CBCT devices and protocols.

Clinical decision-making and importance of the AAE/AAOMR position statement for CBCT examination in endodontic cases

AIM

To compare conventional radiographic and cone beam computed tomography (CBCT) findings with reference to the American Association of Endodontics and American Academy of Oral and Maxillofacial Radiology (AAE/AAOMR) joint position statement and to determine the effect of the CBCT on the initial diagnoses and treatment plans in a single-centre Postgraduate Endodontic Programme.

METHODOLOGY

The clinical CBCT scans of patients, treated at the Endodontic Department of the University of British Columbia, were reviewed for CBCT referrals by comparing them with corresponding radiographs. The features considered were periapical lesions, missed/extra canals, root fractures, complex anatomy, calcified canals and root resorption of tooth/teeth in question. Reasons for the CBCT prescriptions were assigned to 3 groups: to formulate the primary diagnosis, to confirm the diagnosis achieved by clinical examination and conventional radiographs, and to assist in treatment planning. Variables were compared statistically using chi-square and McNemar tests.

RESULTS

A total of 128 CBCT examinations were performed on 110 patients. No CBCT examination was performed more than once on the same tooth. Overall, 76% of CBCT examinations were performed on previously root filled teeth. CBCT images revealed a significantly higher incidence of periapical lesions (P = 0.002), missed canals (P < 0.001), vertical root fractures (P = 0.004) and complex anatomy (P = 0.008) than periapical radiographs. CBCT was prescribed most frequently to assist surgical treatment planning (62%) rather than for generating a diagnosis (9%) or confirming diagnoses (29%). Both the diagnosis (P = 0.001) and the treatment plan (P = 0.005) initially made by examining periapical radiographs were altered significantly by the subsequent CBCT examination by revealing information such as new periapical lesions, missed canals or involvement of buccal or lingual cortical bone.

CONCLUSION

CBCT examinations were prescribed mainly to assist treatment planning rather than for diagnosis. The majority of CBCT examinations were performed on previously root filled teeth. The additional information obtained from CBCT scans resulted in the alteration of the initial diagnoses as well as subsequent treatment plans in 59 out of 128 cases.

Periradicular Lesions in Cancellous Bone Can Be Detected Radiographically

INTRODUCTION

The purpose of this study was to evaluate whether naturally occurring periradicular lesions confined to cancellous bone can be detected on periapical digital radiography and whether the size of the lesion had any effect on lesion detection.

METHODS

One hundred twenty-nine roots were chosen based on cone-beam computed tomographic imaging and categorized as having no lesion, a lesion confined to cancellous bone, a lesion that encroaches on junctional corticocancellous trabeculae, or a lesion with cortical involvement. The largest buccolingual dimension of the lesions was measured on cone-beam computed tomographic imaging. Two observers separately viewed the corresponding periapical radiographs in their original version as well as in the edge-enhanced setting on MiPACS (LEAD Technologies Inc, Charlotte, NC). Observers were asked to evaluate and interpret the periapical radiographs as having a lesion present, absent, or "unsure." Evaluations of images were conducted at 2 times 1 week apart. Data were analyzed, and the level of significance was set at P = .05.

RESULTS

Lesion size, not the degree of cortical involvement, significantly affected the observers' ability to accurately detect lesions. As the size of the lesion increased, the probability of correctly identifying a lesion increased (P = .0008). Lesions were correctly identified 97.6%, 94.1%, 91.6%, and 89.3% of the time, respectively, when in cortical bone, at the junction of corticocancellous bone, in cancellous bone, and when no lesion was present. Observers were "unsure" whether a lesion was present or absent 10.7% of the time. Only lesions in cortical bone significantly increased observers' certainty in making a diagnosis.

CONCLUSIONS

This study concluded that lesions confined to cancellous bone can be detected radiographically at a high rate. Lesion size was positively correlated with correct lesion identification, whereas the degree of cortical involvement had no significant effect. This suggests that lesion size may be a better predictor for correct lesion identification than lesion location.

Retrieving 3D medical data along fitted curved slices and their display

BACKGROUND

Computeros tomography and magnetic resonance imaging are usually offered to the clinician in the form of sequences of axial, sagittal and coronal planar cuts. Frequently this does not allow for the full inspection of the morphology of the area of interest, because it is limited by the planarity. Efforts have been made to extract information along curved slices but their planar display is prone to metric deformation.

METHODS

We propose a new visualization alternative of 3D medical volumes using curved slices adapted to areas of interest. We use surfaces fitted to specific organs as visualization canvasses. We describe the differential geometry techniques used to build the surfaces that may be isometrically flattened. These are referred to as develpable surfaces.

RESULTS

We show concrete examples deemed useful for the development of clinical and educational tools. Our examples are centered in magnetic resonance data of the rotator cuff muscle complex and computed tomography data of maxillofacial and dental studies. We also look at the extraction and display of information from volumes of aortic aneurysms along transversal surfaces.

DISCUSSION

We look at extensions of the technique and propose further possible clinical use of texturized surfaces in the context of volume navigation.

CONCLUSIONS

We presented a technique to extract information from computer tomography and magnetic resonance volumes, using two different texturization techniques. In the cases that the fitting surfaces are chosen to be developable, they may be flattened without distortion. We also discuss how tu use the technique in other visualization tasks such as volume navigation and detection of volumetric features.

Detection of Simulated Periapical Lesion in Intraoral Digital Radiography with Different Brightness and Contrast

Objective:

To assess the detection of simulated periapical lesions in digital intraoral radiography with different levels of brightness and contrast combinations, and to investigate the observers’ preference of image quality for this diagnostic task.

Methods:

Digital radiographs were acquired prior to periapical lesion simulation and after each one of four defects enlargement. Original images were adjusted in 4 brightness and contrast combinations. Five observers evaluated the images according to the presence of periapical lesion on a 5-point scale. In a second moment, the observers ordinated the images subjectively, according to quality, from the best to the worst to detect the bone defect. The area under the receiver operating characteristic curve was calculated for the diagnostic values and compared by two-way ANOVA. The significance level was set at 5% (P<0.05).

Results:

No differences were found between the diagnostic values of the five combinations of brightness and contrast (P>0.05). The overall results showed low values of area under the Receiver Operating Characteristic (ROC) curve and sensitivity of the periapical radiography in the detection of periapical lesions of sizes from 1 to 3, which rose substantially in size 4. For image quality, combinations with the lowest brightness and highest contrast were preferred by the observers in 58% of the cases.

Conclusion:

Brightness and contrast adjustments do not influence the detection of simulated periapical lesions in digital intraoral radiography. Lower brightness and higher contrast images were preferred for this diagnostic task.

Effectiveness of Using a Mobile App to Improve Dental Students' Ability to Identify Endodontic Complications from Periapical Radiographs

The aim of this study was to evaluate the feasibility and effectiveness of a mobile application as a supplementary tool in the radiographic diagnosis of endodontic complications by dental students. Radiographic images of the following endodontic conditions were selected: 1) absence of endodontic treatment (ET) without periapical lesion (PL); 2) absence of ET with PL; 3) satisfactory ET without PL; 4) satisfactory ET with PL; 5) unsatisfactory ET without PL; 6) unsatisfactory ET with PL; 7) fractured instrument; 8) deviated cast post; 9) root fracture; and 10) root resorption. In 2018, images were evaluated by 20 students at a dental school in Brazil who had been divided into experimental and control groups. The experimental group was permitted to use the Kahoot! mobile application (app) to access reference images of endodontic conditions. Reference standards were established through consensus by two endodontists and three oral radiologists. The results showed that intraobserver agreement ranged from moderate to substantial for both groups. Significant differences from the specialists' reference standards were found in the evaluation of conditions 4 and 10 for the experimental group, which used the app (p<0.001), and conditions 1, 4, 6, 7, 8, and 10 for the control group, which did not use the app (p<0.05). No statistically significant differences were found in accuracy, sensitivity, or specificity values between the groups for any of the endodontic conditions evaluated (p>0.05). This study found that the use of a mobile app containing reference images improved the students' ability to diagnose endodontic complications, suggesting it would be a valuable supplementary tool in dental education.

Correlation between crestal alveolar bone loss with intracanal bacteria and apical lesion area in necrotic teeth

OBJECTIVE

This study aimed to analyze the correlation between crestal alveolar bone loss with the presence of some bacterial species in root canals and the apical lesion area of necrotic teeth.

DESIGN

Data from 20 patients with diagnosis of pulp necrosis and acute apical abscesses, without active periodontal diseases, were evaluated. Patients with history of antibiotic usage three months prior to the study, with exposed pulp cavity, and with probing depth >3 mm were not included. The root size, the distance between the bone crest to the tooth apex in the mesial and distal surfaces, and the apical lesion area were measured from standard periapical radiographies by a calibrated examiner. Root canal samples were collected using sterilized paper points. In multirooted teeth, the largest root canal was sampled. Culture, microbial isolation and identification by phenotypic methods were performed. Spearman correlation and exact Fischer test were calculated between higher/lower existing bone crests, according to the median and the presence of specific bacteria.

RESULTS

No statistically significant differences were found between occurrence of pathogenic bacteria, such as Porphyromonas gingivalis, Porphyromonas endodontalis, and Prevotella intermedia, and groups with higher/lower degree of bone loss (p > 0.05). A negative significant correlation was found between Parvimonas micra and periodontal bone loss (p = 0.02). Additionally, no statistically significant association was found between crestal bone loss and the apical lesion area.

CONCLUSIONS

It was concluded that, in patients without active periodontitis, the presence of pathogenic bacteria in the root canal was not correlated with periodontal bone loss.

An Insight into Histopathologic Examination as a Gold Standard for the Diagnosis of Chronic Apical Periodontitis

Objective: The purpose of our study was to determine the level of correlation between histopathologic results after surgery for chronic apical periodontitis and the radiographic and clinical diagnosis. The status of gold standard technique of histologic examination was evaluated in the diagnosis of apical radiolucency in necrotic teeth.

Methods: Out of 154 patients with incorrect root fillings and apical radiolucency included in an endodontic retreatment protocol, 87 patients (108 teeth) were scheduled for apical surgery at 3-6 months control recall. Clinical and radiographic exams were completed prior to surgery and compared to the histological results of apical biopsies. The collected data were statistically analyzed with the SPSS version 20.0 and the Chi-square test was used to determine the associations between clinical and histologic diagnosis. A value of p <0.05 was considered statistically significant.

Results: There was a statistically significant difference between the number of cases diagnosed as granulomas or cysts during clinical and radiological evaluation compared to histologic evaluation of tissue samples, with 40.9% to 75.9% and 54.2% to 16.8% respectively (p<0.05).

Conclusions: The final diagnosis was obtained only after histologic examination of apical tissue samples, which means that the observations made based on radiologic investigations must be confirmed by biopsy.

Methodological and Reporting Quality of Systematic Reviews and Meta-analyses in Endodontics

INTRODUCTION

The aim of this systematic review (SR) was to evaluate the quality of SRs and meta-analyses (MAs) in endodontics.

METHODS

A comprehensive literature search was conducted to identify relevant articles in the electronic databases from January 2000 to June 2017. Two reviewers independently assessed the articles for eligibility and data extraction. SRs and MAs on interventional studies with a minimum of 2 therapeutic strategies in endodontics were included in this SR. Methodologic and reporting quality were assessed using A Measurement Tool to Assess Systematic Reviews (AMSTAR) and Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA), respectively. The interobserver reliability was calculated using the Cohen kappa statistic. Statistical analysis with the level of significance at P < .05 was performed using Kruskal-Wallis tests and simple linear regression analysis.

RESULTS

A total of 30 articles were selected for the current SR. Using AMSTAR, the item related to the scientific quality of studies used in conclusion was adhered by less than 40% of studies. Using PRISMA, 3 items were reported by less than 40% of studies, which were on objectives, protocol registration, and funding. No association was evident comparing the number of authors and country with quality. Statistical significance was observed when quality was compared among journals, with studies published as Cochrane reviews superior to those published in other journals. AMSTAR and PRISMA scores were significantly related.

CONCLUSIONS

SRs in endodontics showed variability in both methodologic and reporting quality.

Clinical efficacy of main radiological diagnostic methods for odontogenic maxillary sinusitis

The objective of the study was to compare the ability of dental, ENT and radiology specialists to identify the dental cause of maxillary sinusitis with conventional computed tomography, dental and panoramic radiographs. Out of 34 dental records from subjects treated at ENT and Oral and Maxillofacial Surgery Department, LUHS Kaunas Clinics, 22 females and 12 males with the diagnosis of odontogenic maxillary sinusitis, periapical (DPA), panoramic (DPR) and computed tomography (CT) images of posterior maxilla were selected for further studies. In total, 39 sinuses with an odontogenic and 37 sinuses with only rhinogenic cause (control group) were included in the study. Sinuses with mucosal thickening less than 3 mm were excluded from the research. Each image was evaluated by 5 endodontologists, 5 oral surgeons, 6 general dentists, 6 otorhinolaryngologists and an experienced oral radiologist. DPR and DPA views were not evaluated by ENT specialists. The dental cause of maxillary sinusitis was marked according to the given scale. Intraclass correlation coefficient and ROC curve statistical analysis were performed. The best accuracy was observed when CT views were evaluated by experienced oral radiologist and oral surgeons: the AUC was 0.958 and 0.859, respectively. DPR views showed the best accuracy when evaluated by oral surgeons (0.763) and DPA-by endodontologists (0.736). The highest inter-rater agreement was observed between experienced oral radiologist and oral surgeons/otorhinolaryngologists (0.87/0.78) evaluating CT. Sensitivity and specificity of CT were 89.7 and 94.6%, DPR-68.2 and 77.3%, DPA-77.9 and 67%. Identification of dental cause of maxillary sinusitis sometimes is a challenge, which depends on radiological method and, more importantly, on evaluator's experience.

Endodontic procedures for retreatment of periapical lesions

BACKGROUND

When primary root canal therapy fails, periapical lesions can be retreated with or without surgery. Root canal retreatment is a non-surgical procedure that involves removal of root canal filling materials from the tooth, followed by cleaning, shaping and obturating of the canals. Root-end resection is a surgical procedure that involves exposure of the periapical lesion through an osteotomy, surgical removal of the lesion, removal of part of the root-end tip, disinfection and, commonly, retrograde sealing or filling of the apical portion of the remaining root canal. This review updates one published in 2008.

OBJECTIVES

To assess effects of surgical and non-surgical therapy for retreatment of teeth with apical periodontitis.To assess effects of surgical root-end resection under various conditions, for example, when different materials, devices or techniques are used.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Oral Health Trials Register (to 10 February 2016), the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 1), MEDLINE Ovid (1946 to 10 February 2016) and Embase Ovid (1980 to 10 February 2016). We searched the US National Registry of Clinical Trials (ClinicalTrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform for ongoing trials (to 10 February 2016). We placed no restrictions regarding language and publication date. We handsearched the reference lists of the studies retrieved and key journals in the field of endodontics.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) involving people with periapical pathosis. Studies could compare surgery versus non-surgical treatment or could compare different types of surgery. Outcome measures were healing of the periapical lesion assessed after one-year follow-up or longer; postoperative pain and discomfort; and adverse effects such as tooth loss, mobility, soft tissue recession, abscess, infection, neurological damage or loss of root sealing material evaluated through radiographs.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data from included studies and assessed their risk of bias. We contacted study authors to obtain missing information. We combined results of trials assessing comparable outcomes using the fixed-effect model, with risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, and 95% confidence intervals (CIs). We used generic inverse variance for split-mouth studies.

MAIN RESULTS

We included 20 RCTs. Two trials at high risk of bias assessed surgery versus a non-surgical approach: root-end resection with root-end filling versus root canal retreatment. The other 18 trials evaluated different surgical protocols: cone beam computed tomography (CBCT) versus periapical radiography for preoperative assessment (one study at high risk of bias); antibiotic prophylaxis versus placebo (one study at unclear risk); different magnification devices (loupes, surgical microscope, endoscope) (two studies at high risk); types of incision (papilla base incision, sulcular incision) (one study at high risk and one at unclear risk); ultrasonic devices versus handpiece burs (one study at high risk); types of root-end filling material (glass ionomer cement, amalgam, intermediate restorative material (IRM), mineral trioxide aggregate (MTA), gutta-percha (GP), super-ethoxy benzoic acid (EBA)) (five studies at high risk of bias, one at unclear risk and one at low risk); grafting versus no grafting (three studies at high risk and one at unclear risk); and low energy level laser therapy versus placebo (irradiation without laser activation) versus control (no use of the laser device) (one study at high risk).There was no clear evidence of superiority of the surgical or non-surgical approach for healing at one-year follow-up (RR 1.15, 95% CI 0.97 to 1.35; two RCTs, 126 participants) or at four- or 10-year follow-up (one RCT, 82 to 95 participants), although the evidence is very low quality. More participants in the surgically treated group reported pain in the first week after treatment (RR 3.34, 95% CI 2.05 to 5.43; one RCT, 87 participants; low quality evidence).In terms of surgical protocols, there was some inconclusive evidence that ultrasonic devices for root-end preparation may improve healing one year after retreatment, when compared with the traditional bur (RR 1.14, 95% CI 1.00 to 1.30; one RCT, 290 participants; low quality evidence).There was evidence of better healing when root-ends were filled with MTA than when they were treated by smoothing of orthograde GP root filling, after one-year follow-up (RR 1.60, 95% CI 1.14 to 2.24; one RCT, 46 participants; low quality evidence).There was no evidence that using CBCT rather than radiography for preoperative evaluation was advantageous for healing (RR 1.02, 95% CI 0.70 to 1.47; one RCT, 39 participants; very low quality evidence), nor that any magnification device affected healing more than any other (loupes versus endoscope at one year: RR 1.05, 95% CI 0.92 to 1.20; microscope versus endoscope at two years: RR 1.01, 95% CI 0.89 to 1.15; one RCT, 70 participants, low quality evidence).There was no evidence that antibiotic prophylaxis reduced incidence of postoperative infection (RR 0.49, 95% CI 0.09 to 2.64; one RCT, 250 participants; low quality evidence).There was some evidence that using a papilla base incision (PBI) may be beneficial for preservation of the interdental papilla compared with complete papilla mobilisation (one RCT (split-mouth), 12 participants/24 sites; very low quality evidence). There was no evidence of less pain in the PBI group at day 1 post surgery (one RCT, 38 participants; very low quality evidence).There was evidence that adjunctive use of a gel of plasma rich in growth factors reduced postoperative pain compared with no grafting (measured on visual analogue scale: one day postoperative MD -51.60 mm, 95% CI -63.43 to -39.77; one RCT, 36 participants; low quality evidence).There was no evidence that use of low energy level laser therapy (LLLT) prevented postoperative pain (very low quality evidence).

AUTHORS' CONCLUSIONS

Available evidence does not provide clinicians with reliable guidelines for treating periapical lesions. Further research is necessary to understand the effects of surgical versus non-surgical approaches, and to determine which surgical procedures provide the best results for periapical lesion healing and postoperative quality of life. Future studies should use standardised techniques and success criteria, precisely defined outcomes and the participant as the unit of analysis.

Endodontic Treatment of an Autogenous Transplanted Tooth Using an Er,Cr:YSGG Laser and Radial Firing Tips: Case Report

OBJECTIVE AND BACKGROUND

Although several surgical techniques have been reported, no study has yet reported alternative strategies for endodontic treatment of autogenous transplanted teeth. Therefore, the aim of this clinical report is to present the long-term endodontic outcome of a nonvital autogenously transplanted third molar treated with an Er,Cr:YSGG laser and radial firing tips (RFTs).

CASE REPORT

Autogenous tooth transplantation can be considered an alternative to restore edentulous areas and, in donor's teeth with complete root formation, root canal treatment should be performed up to 14 days following transplantation. In the present case report, the patient returned only after 6 months, with clinical and radiological signs of apical periodontitis (AP) associated with the transplanted tooth.

METHODS

Instead of traditional endodontic chemical irrigants or medications, the protocol for smear-layer removal and root canal disinfection was based on intracanal irradiation with an Er,Cr:YSGG laser and RFTs.

RESULTS

After 3-years' follow-up, the complete reestablishment of the periodontal ligament and the arrest of the resorptive process could be noticed.

CONCLUSIONS

This protocol has shown to be effective for the endodontic treatment of a transplanted multi-rooted tooth with AP. Further randomized clinical trials should be conducted to clearly demonstrate the effectiveness of this laser-assisted endodontic protocol.

Critical Assessment of Search Strategies in Systematic Reviews in Endodontics

INTRODUCTION

The aim of this study was to perform an overview of literature search strategies in systematic reviews (SRs) published in 2 endodontic journals, Journal of Endodontics and International Endodontic Journal.

METHODS

A search was done by using the MEDLINE (PubMed interface) database to retrieve the articles published between January 1, 2000 and December 31, 2015. The last search was on January 10, 2016. All the SRs published in the 2 journals were retrieved and screened. Eligible SRs were assessed by using 11 questions about search strategies in the SRs that were adapted from 2 guidelines (ie, AMSTAR checklist and the Cochrane Handbook).

RESULTS

A total of 83 SRs were retrieved by electronic search. Of these, 55 were from the Journal of Endodontics, and 28 were from the International Endodontic Journal. After screening, 2 SRs were excluded, and 81 SRs were included in the study. Some issues, such as search of grey literature and contact with study authors, were not fully reported (30% and 25%, respectively). On the other hand, some issues, such as the use of index terms and key words and search in at least 2 databases, were reported in most of the SRs (97% and 95%, respectively). The overall quality of the search strategy in both journals was 61%. No significant difference was found between the 2 journals in terms of evaluation criteria (P > .05).

CONCLUSIONS

There exist areas for improving the quality of reporting of search strategies in SRs; for example, grey literature should be searched for unpublished studies, no language limitation should be applied to databases, and authors should make an attempt to contact the authors of included studies to obtain further relevant information.

Computed tomography (CT) in the selection of treatment for root-filled maxillary molars with apical periodontitis

OBJECTIVES

The aims of this study were to evaluate whether the use of CT facilitates agreement among endodontists in selecting treatments for root-filled maxillary molars with apical periodontitis and to assess the efficacy of CT in choosing a treatment for such teeth.

METHODS

39 root-filled maxillary molars from 34 patients with suspected apical periodontitis were independently evaluated by 4 endodontists and 1 postgraduate student (decision-makers). Treatment decisions were made based on intra-oral radiographs and a fictive clinical history. After 1-3 months, the same decision-makers repeated the examination of the same teeth but with additional information from a CT examination. Agreement between decision-makers with or without the availability of the CT results was measured with Cohen's kappa coefficient. Differences in selected treatments with or without accessibility to the CT results were plotted for the same endodontists using descriptive statistics.

RESULTS

The agreement in assessments among endodontists was slight or fair before the CT results were available (range: 0.081-0.535). No increase was observed after reviewing the CT results (range: 0.116-0.379). After the use of CT, the treatment plan was changed 38-76% of the time by all decision-makers, and the changes affected 57.8% of the cases in the study.

CONCLUSIONS

The endodontists in this study exhibited a low degree of agreement when choosing a treatment for root-filled maxillary molars with apical periodontitis. A CT examination of the investigated teeth did not result in a significantly higher degree of agreement, and CT frequently contributed to a shift in the selected therapy.

Dose optimization by altering the operating potential and tube current exposure time product in dental cone beam CT: a systematic review

OBJECTIVES

Current guidelines highlight the need to optimize exposure parameters on CBCT equipment to levels that are as low as diagnostically acceptable. This systematic review aimed to answer the question "Can altering operating potential (kV) and tube current exposure time product (mAs) on CBCT machines reduce radiation dose to patients undergoing dental and/or maxillofacial scans without a detrimental impact on image quality/diagnostic accuracy?"

METHODS

Studies were selected and results reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method. For each individual study, two authors (RG and JD or KH) independently extracted data using a specifically designed collection form, and an overall quality value was assigned using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Any disagreements in the overall quality value of a study were resolved by discussion between the current authors.

RESULTS

Nearly 75% of studies were considered to be of low or very low methodological quality using the GRADE system, and more studies stated that their results applied only in the specific situations they had investigated. However, most studies demonstrated that patient dose reduction is possible without a clinically relevant reduction in image quality.

CONCLUSIONS

For many CBCT machines, it should be possible to optimize one, or more, of the investigated exposure parameters and therefore reduce patient radiation dose, while maintaining diagnostic image quality for some diagnostic tasks. However, more rigorous research is still required.

Noninvasive differential diagnosis of dental periapical lesions in cone-beam CT scans

PURPOSE

This paper proposes a novel application of computer-aided diagnosis (CAD) to an everyday clinical dental challenge: the noninvasive differential diagnosis of periapical lesions between periapical cysts and granulomas. A histological biopsy is the most reliable method currently available for this differential diagnosis; however, this invasive procedure prevents the lesions from healing noninvasively despite a report that they may heal without surgical treatment. A CAD using cone-beam computed tomography (CBCT) offers an alternative noninvasive diagnostic tool which helps to avoid potentially unnecessary surgery and to investigate the unknown healing process and rate for the lesions.

METHODS

The proposed semiautomatic solution combines graph-based random walks segmentation with machine learning-based boosted classifiers and offers a robust clinical tool with minimal user interaction. As part of this CAD framework, the authors provide two novel technical contributions: (1) probabilistic extension of the random walks segmentation with likelihood ratio test and (2) LDA-AdaBoost: a new integration of weighted linear discriminant analysis to AdaBoost.

RESULTS

A dataset of 28 CBCT scans is used to validate the approach and compare it with other popular segmentation and classification methods. The results show the effectiveness of the proposed method with 94.1% correct classification rate and an improvement of the performance by comparison with the Simon's state-of-the-art method by 17.6%. The authors also compare classification performances with two independent ground-truth sets from the histopathology and CBCT diagnoses provided by endodontic experts.

CONCLUSIONS

Experimental results of the authors show that the proposed CAD system behaves in clearer agreement with the CBCT ground-truth than with histopathology, supporting the Simon's conjecture that CBCT diagnosis can be as accurate as histopathology for differentiating the periapical lesions.

Periapical repair following endodontic surgery: two- and three-dimensional imaging evaluation methods

This study quantitatively assessed the periapical bone repair following endodontic surgery, using planimetric evaluation based on two- (conventional and digital intraoral radiographic images - IRs) and three-dimensional (cone beam computed tomography - CBCT) evaluation. Eleven maxillary anterior teeth (of 11 patients) with periapical bone lesions and indication for surgical endodontic treatment were selected. IRs and CBCT images were acquired before the endodontic surgery, and 48 h, 4, and 8-months after the surgery. In each period of evaluation, the area (mm2) of the bone lesion was measured in the images, and the values for the three methods were compared. The area in the CBCT images was measured in the mesio-distal sections comprising the largest diameter of the lesion. Data were submitted to repeated measures 2-way ANOVA and t-tests with Bonferroni correction. There was significant difference between the periods of evaluation (p=0.002) regarding the assessed periapical bone lesion area. There was no statistically significant difference between the methods of evaluation (p=0.023). In the CBCT images the lesion areas were 10% larger than those observed in the conventional IRs (22.84 mm2) and 15% larger than those observed in the digital IRs (21.48 mm2). From the baseline (40.12 mm2) to 4 (20.06 mm2) and 8-months (9.40 mm2), reductions of 50 and 77% in the lesion area, respectively, were observed (p<0.0001). From 4 to 8-months, this value was 53%. Progressive bone repair could be seen from 48 h to 8-months following endodontic surgery based on two- (conventional and digital IRs) and three-dimensional (CBCT) evaluation. CBCT images provided results similar to those assessed by means of IRs.

CBCT-based evaluation of integrity of cortical sinus close to periapical lesions

The purpose of the present study was to test the applicability of cone beam computed tomography (CBCT) to evaluate the integrity of the cortical sinus close to periapical lesions. Two observers analyzed samples of 64 alveoli of first molar roots in macerated swine maxillas prepared with perchloric acid to simulate periapical lesions. The specimens were evaluated using CBCT (55-mm high and 100-mm diameter cylinder at 0.2-mm voxel resolution) for the presence of oroantral communication (OAC) caused by the simulated lesions. Sensitivity, specificity, and accuracy were calculated. Fair values were obtained for accuracy (66%-78%) and good values for specificity (70%-98%), whereas the values for sensibility showed relevant variation (41%-78%). For this reason, the interobserver agreement score was weak. CBCT proved capable of evaluating the integrity of the cortical sinus (absence of oroantral communication) when it lies close to an apical periodontitis lesion. However, the low interobserver agreement reflects the difficulty in performing diagnoses when OAC is adjacent to a periapical lesion, using the acquisition protocol adopted in this research. This could be attributed to the high level of image noise.

Association between chronic apical periodontitis and low-birth-weight preterm births

INTRODUCTION

The objective of this study was to investigate the association between chronic apical periodontitis (CAP) and low-birth-weight preterm births (LBWPB).

METHODS

Sixty-three women in postpartum period were included in this case-control study. The case group consisted of mothers of LBWPB infants (n = 33), and the control group was represented by mothers of newborns at term (n = 30). The CAP diagnosis was performed by using periapical radiographs through the periapical index in postpartum period. The χ(2) test, Fisher exact test, and linear and logistic regression were used for statistical analysis.

RESULTS

It was observed that CAP was present in 54.5% of mothers in the case group and 20.0% in the control group (P = .004); postpartum women with CAP had about 3.5 times greater odds of LBWPB newborns than women without CAP (adjusted odds ratio, 3.52; 95% confidence interval, 1.01-12.32). Postpartum women who reported 6 or more prenatal consultations reduced odds of LBWPB newborns in 80% (adjusted odds ratio, 0.20; 95% CI, 0.06-0.69). It can be estimated that the increase of 1 unit of periapical index had a significant association with the reduction of 1½ gestational weeks in the crude analysis (β = -1.5, P = .010) and the reduction of 211 g in birth weight after the adjusted analysis (β = -211, P = .058).

CONCLUSIONS

Prematurity and low birth weight were associated with radiographically detected CAP. Women with CAP in postpartum period had greater odds of LBWPB.