Evaluation of furcation involvement with diagnostic imaging methods: a systematic review

Accuracy of Ionizing-Radiation-Based and Non-Ionizing Imaging Assessments for the Diagnosis of Periodontitis: Systematic Review and Meta-Analysis

AIMS

To evaluate the diagnostic accuracy of periapical, bitewing or panoramic radiographs (standard 2D radiographs) in detecting and monitoring periodontitis (PICO 1) and to assess the clinical relevance of alternative and emerging diagnostic methods (e.g., cone-beam computed tomography [CBCT], magnetic resonance imaging [MRI], ultrasound imaging [USG]) compared to standard 2D radiographs or clinical/intra-surgical examination in the diagnosis and surveillance of the disease (PICO 2).

MATERIALS AND METHODS

A systematic literature search was conducted through MEDLINE EMBASE, Scopus and Cochrane Library. When feasible (n > 2 comparable studies), a meta-analysis of diagnostic accuracy was performed.

RESULTS

For PICO 1, 26 studies met the inclusion criteria. Pooled-data analysis from three studies showed a sensitivity of 0.77 (95% confidence interval, CI: 0.66-0.85), specificity of 0.76 (95% CI: 0.64-0.84) and accuracy of 0.82, with a diagnostic odds ratio (DOR) of 137.99 (95% CI: 6.99-368.90). For PICO 2, 51 articles were included dealing with different techniques. The meta-analysis for CBCT (three studies) showed a pooled sensitivity and specificity of 0.98 (95% CI: 0.96-1.00) and 0.98 (95% CI: 0.95-1.00), respectively, and a diagnostic accuracy of 0.99 in the detection of furcation involvement compared to intra-surgical measurements.

CONCLUSIONS

Standard 2D radiographs appear to have adequate diagnostic accuracy for periodontitis, while CBCT is highly sensitive and specific to detect and classify furcation involvement. The role of non-ionizing techniques (MRI and USG) in diagnosing periodontitis remains under investigation.

Enhancing furcation involvement classification on panoramic radiographs with vision transformers

BACKGROUND

The severity of furcation involvement (FI) directly affected tooth prognosis and influenced treatment approaches. However, assessing, diagnosing, and treating molars with FI was complicated by anatomical and morphological variations. Cone-beam computed tomography (CBCT) enhanced diagnostic accuracy for detecting FI and measuring furcation defects. Despite its advantages, the high cost and radiation dose associated with CBCT equipment limited its widespread use. The aim of this study was to evaluate the performance of the Vision Transformer (ViT) in comparison with several commonly used traditional deep learning (DL) models for classifying molars with or without FI on panoramic radiographs.

METHODS

A total of 1,568 tooth images obtained from 506 panoramic radiographs were used to construct the database and evaluate the models. This study developed and assessed a ViT model for classifying FI from panoramic radiographs, and compared its performance with traditional models, including Multi-Layer Perceptron (MLP), Visual Geometry Group (VGG)Net, and GoogLeNet.

RESULTS

Among the evaluated models, the ViT model outperformed all others, achieving the highest precision (0.98), recall (0.92), and F1 score (0.95), along with the lowest cross-entropy loss (0.27) and the highest accuracy (92%). ViT also recorded the highest area under the curve (AUC) (98%), outperforming the other models with statistically significant differences (p < 0.05), confirming its enhanced classification capability. The gradient-weighted class activation mapping (Grad-CAM) analysis on the ViT model revealed the key areas of the images that the model focused on during predictions.

CONCLUSION

DL algorithms can automatically classify FI using readily accessible panoramic images. These findings demonstrate that ViT outperforms the tested traditional models, highlighting the potential of transformer-based approaches to significantly advance image classification. This approach is also expected to reduce both the radiation dose and the financial burden on patients while simultaneously improving diagnostic precision.

Classification of mandibular molar furcation involvement in periapical radiographs by deep learning

Purpose

The purpose of this study was to classify mandibular molar furcation involvement (FI) in periapical radiographs using a deep learning algorithm.

Materials and Methods

Full mouth series taken at East Carolina University School of Dental Medicine from 2011-2023 were screened. Diagnostic-quality mandibular premolar and molar periapical radiographs with healthy or FI mandibular molars were included. The radiographs were cropped into individual molar images, annotated as " healthy" or " FI," and divided into training, validation, and testing datasets. The images were preprocessed by PyTorch transformations. ResNet-18, a convolutional neural network model, was refined using the PyTorch deep learning framework for the specific imaging classification task. CrossEntropyLoss and the AdamW optimizer were employed for loss function training and optimizing the learning rate, respectively. The images were loaded by PyTorch DataLoader for efficiency. The performance of ResNet-18 algorithm was evaluated with multiple metrics, including training and validation losses, confusion matrix, accuracy, sensitivity, specificity, the receiver operating characteristic (ROC) curve, and the area under the ROC curve.

Results

After adequate training, ResNet-18 classified healthy vs. FI molars in the testing set with an accuracy of 96.47%, indicating its suitability for image classification.

Conclusion

The deep learning algorithm developed in this study was shown to be promising for classifying mandibular molar FI. It could serve as a valuable supplemental tool for detecting and managing periodontal diseases.

Biometric analysis of furcation area of molar teeth and its relationship with instrumentation

The anatomy of furcation favours the bacterial retention and makes periodontal debridement as well as oral hygiene procedures difficult. Teeth that have lost attachment to a level of the furcation are said to have a furcal invasion or furcation involved.Involvement of furcation in a multi-rooted tooth poses a very different type of clinical situation in terms of establishment of diagnosis, determination of prognosis and of course planning the treatment modality.The present study was carried out on 200 selected extracted human first and second permanent molar teeth based on a predefined criteria. Teeth with prosthetic crowns, fused or fractured roots, those not fully developed, grossly carious or heavily restored at the cementoenamel junction (CEJ) were excluded from the study. The morphology of the root trunk was recorded by measuring various dimensions of the root trunk,including furcal angle and root trunk volume was calculated by using a custom made special apparatus. The furcation areas were debrided with different types of curettes in the market in order to see how best the instrument could be maneuvered in the furcation area. The data so obtained was statistically analysed using SPSS version 22. The highest root trunk volume and the longest root trunk length were found to be in the maxillary second molar. 48.60% furcations didn't allow instrument engagementof furcation area with standard area specific curettes. The proposal of inclusion of root trunk length (mm) is suggested in addition to classification of FI to have assess prognosis and appropriate treatment for of the involved tooth.

Diagnostic application of intraoral ultrasonography to assess furcation involvement in mandibular first molars

OBJECTIVES

The objectives were to clarify if intraoral ultrasonography (USG) is: (1) more accurate than conventional periodontal examinations in detection of furcation involvement, and (2) comparable to conventional periodontal examinations in accurate horizontal classification of furcation involvement in comparison to cone beam computed tomography (CBCT).

METHODS

The buccal furcation in 61 lower first molars were evaluated with conventional periodontal examinations, intraoral USG and CBCT. The presence and classification of the horizontal depth of furcation involvement were defined clinically by assessment with a Nabers periodontal probe and a periapical radiograph with reference to the bone loss under the fornix. The horizontal depth of furcation involvement was measured in intraoral USG and CBCT images. Based on the measurements, presence diagnosis and horizontal classification were performed. Results from conventional periodontal examinationsand intraoral USG were compared with those from CBCT.

RESULTS

κ value (κ) for agreement of presence diagnosis of furcation involvement between intraoral USG and CBCT was 0.792, while agreement with conventional periodontal examinations was 0.225. Diagnostic accuracy of intraoral USG exhibited higher values (sensitivity: 98.3%, accuracy: 98.4 %) than conventional periodontal examinations (81.4% and 81.9 %). Weighted κ statistics showed substantial agreement in the classification between intraoral USG and CBCT (κ = 0.674). High agreement (ICC: 0.914) for the measurement of horizontal depth of furcation involvement was found between intraoral USG and CBCT.

CONCLUSIONS

Intraoral USG may be a reliable diagnostic tool for assessment of furcation involvement of mandibular molars with a similar performance to CBCT, but without ionizing radiation.

Effects of Advanced Platelet Rich Fibrin (A-PRF+), Enamel Matrix Derivative (EMD) and Open Flap Debridement on clinical and wound healing parameters in molar furcation sites: A case series from a RCT study

Aim

To study the effects of advanced platelet-rich fibrin (A-PRF+) and enamel matrix derivative (EMD) compared to open flap debridement (OFD) alone in molar furcation sites grade II on clinical and wound healing parameters.

Materials and methods

A randomized controlled trial was designed. Eligible patients were randomly allocated to one of three treatment groups: A-PRF+, EMD or OFD. The patients and clinical examiners were blinded for the treatment received. A minimally invasive microsurgical approach was performed for the three modalities. Clinical measurements were scored at baseline and 6 months post-operatively. The clinical healing of each furcation was scored via the Early Wound Healing Index on day 3, 1 week, 2 weeks and 6 weeks.

Results

17 patients (A-PRF+ n = 6, EMD n = 5, OFD n = 6) completed the 6 months of follow-up. The further completion of the trial had to be cancelled due to the COVID-19 pandemic. In three patients in the A-PRF+ group, the grade II of the treated furcation regressed to grade I; the corresponding number in the EMD and OFD groups was zero and one respectively. Further, 3, 1 and 4 patients in the PRF, EMD and OFD groups respectively, showed a gain of bone level ≥1 mm. The defects in the A-PRF+ group showed delayed early healing compared to the EMD and OFD groups.

Conclusion

The case series (RCT design) suggests a slight advantage for A-PRF+ over EMD and OFD, regarding the regressing of a furcation II to grade I; however this treatment showed delayed early wound healing compared to EMD or OFD.

Clinical Trial Registration

https://www.isrctn.com/, identifier ISRCTN13520922.

Comparison between Conventional Modality Versus Cone-Beam Computer Tomography on the Assessment of Vertical Furcation in Molars

This study aimed to assess the accuracy of diagnosis of vertical furcation subclass in molars using periapical radiographs (PAs) and clinical chartings compared against cone-beam computer tomography (CBCT) as the gold standard. The protocol involved examiners with different levels of experience. This retrospective radiographic study retrieved 40 molar teeth with full periodontal chartings, PAs, and CBCT records. Fifteen examiners with different levels of experience evaluated the PAs and periodontal chartings to assess the vertical depth of furcation and, thus, the vertical subclassification. CBCT was used as the gold standard for comparison. The accuracy of vertical furcal depth measured was assessed together with the accuracy of vertical subclassification assignment. The reliability of the conventional diagnostic modality among the examiners was also evaluated. A linear mixed model adjusted for the CBCT vertical furcal depth measurement was constructed to determine if tooth position, horizontal furcation distribution, and examiner experience level affect the bias in the vertical depth of furcation measurement. The reliability of the conventional periodontal diagnostic method in measuring vertical furcal depth was found to be fair, while vertical subclass assignment was moderate. Significantly better reliability during subclass assignment was found with mandibular molars (p < 0.001) and in maxillary molars with isolated buccal class II furcation. Within the study’s limitations, conventional periodontal diagnostics based on periapical radiographs and clinical periodontal chartings appear to be in poor to fair agreement with CBCT (gold standard) when measuring the vertical depth of furcation. Examiners with the least experience were more prone to bias when estimating the vertical furcal depth.