Reliability and Reproducibility of Manual and Automated Volumetric Measurements of Periapical Lesions

Clinically Oriented CBCT Periapical Lesion Evaluation via 3D CNN Algorithm

Apical periodontitis (AP) is one of the most prevalent disorders in dentistry. However, it can be underdiagnosed in asymptomatic patients. In addition, the perioperative evaluation of 3-dimensional (3D) lesion volume is of great clinical relevance, but the required slice-by-slice manual delineation method is time- and labor-intensive. Here, for quickly and accurately detecting and segmenting periapical lesions (PALs) associated with AP on cone beam computed tomography (CBCT) images, we proposed and geographically validated a novel 3D deep convolutional neural network algorithm, named PAL-Net. On the internal 5-fold cross-validation set, our PAL-Net achieved an area under the receiver operating characteristic curve (AUC) of 0.98. The algorithm also improved the diagnostic performance of dentists with varying levels of experience, as evidenced by their enhanced average AUC values (junior dentists: 0.89-0.94; senior dentists: 0.91-0.93), and significantly reduced the diagnostic time (junior dentists: 69.3 min faster; senior dentists: 32.4 min faster). Moreover, our PAL-Net achieved an average Dice similarity coefficient over 0.87 (0.85-0.88), which is superior or comparable to that of other existing state-of-the-art PAL segmentation algorithms. Furthermore, we validated the generalizability of the PAL-Net system using multiple external data sets from Central, East, and North China, showing that our PAL-Net has strong robustness. Our PAL-Net can help improve the diagnostic performance and speed of dentists working from CBCT images, provide clinically relevant volume information to dentists, and can potentially be applied in dental clinics, especially without expert-level dentists or radiologists.

Volumetric Assessment of Apical Periodontitis Using Cone-Beam Computed Tomography-A Systematic Review

This systematic review aimed to investigate the scientific literature on volumetric studies concerning the diagnosis and treatment of apical periodontitis using CBCT. A systematic review protocol was written following the preferred reporting items for the systematic reviews and meta-analyses (PRISMA) checklist. Four electronic databases were searched for relevant publications in English, which were published up to 21 January 2023. The inclusion criteria and corresponding search keys were applied. The risk of bias was assessed using the Joanna Briggs Institute Meta-Analysis of Statistic Assessment and Review Instrument. The search strategy identified 202 studies, with 123 studies excluded during the title and abstract screening and 47 studies left for full text screening. A total of 17 studies met the inclusion criteria. The lesion volume was measured and classified according to different indices which compared the effectiveness of their diagnostics. Moreover, the volume of AP lesions increased with the thickness of the maxillary sinus mucosa in primary and secondary infections and decreased due to endodontic treatment. Volumetric measurements using CBCT are useful in the correct definition of periapical tissue pathosis using a CBCT periapical volume index and assessment of the dynamics of the treatment of apical lesions.

Acemannan induces rapid early osseous defect healing after apical surgery: A 12-month follow-up of a randomized controlled trial

Background/purpose

Acemannan is an osteoinductive material. This study's objective was to compare the outcomes of bone defect healing using 3-dimensional images after apical surgery with or without adding acemannan sponges.

Materials and methods

Twenty-two anterior teeth from 9 males and 13 females requiring apical surgery were included in this randomized controlled trial. Post-surgery, the bone defects were randomly divided into three groups: blood clot control, 5-, or 10-mg acemannan sponge groups. CBCT scans were taken immediately (baseline), 3-, 6-, and 12-month post-surgery. Sagittal serial sections (1 mm thick slices parallel to the long axis of the tooth) of the defect image were created. The defect boundary was located and the total bone defect volume (BDV) was calculated from the sum of the volume of the serial defect sections. The bone healing was assessed by the percentage of total bone defect volume reduction (%ΔBDV). The paired t-test and one-way ANOVA were used to analyze the differences within each group and between groups, respectively.

Results

The baseline mean BDV of the control, 5-, and 10-mg acemannan groups were not significantly different (p > 0.05). After treatment, the mean BDV for each group was reduced in a time-dependent manner. Compared with the control group, the 5- and 10-mg acemannan groups had a significantly greater %ΔBDV (approximately 2- and 1.89-fold) at 3-months post-surgery, respectively (p < 0.05). However, at the 6- and 12- month follow-up, the %ΔBDV was not significantly different between the groups.

Conclusion

These data suggest acemannan enhanced early bone healing after apical surgery.