Dento maxillo facial radiology最新文献

Objective: The aim of this study was to investigate MR sialography and SPECT/CT for parotid glands in Sjögren's syndrome patients.

Methods: Thirty Sjögren's syndrome patients underwent MR sialography and SPECT/CT. The MR sialographic stagings of Sjögren's syndrome were determined by the criteria (stage 0: normal; stage 1: punctate appearance; stage 2: globular appearance; stage 3: cavitary appearance; stage 4: destructive appearance). The maximum standardized uptake value (SUVmax) of the right and left parotid glands with SPECT/CT was obtained using a workstation and software. MR sialographic stagings and SUVmax of parotid glands were evaluated at pre- and post-stimulation and ratio of pre- to post-stimulation.

Results: Regarding pre-stimulation, the SUVmax of stage 0 (31.9 ± 19.3) was significantly higher than that of stage 2 (19.7 ± 7.5, P = .046), stage 3 (10.2 ± 7.1, P < .001) and stage 4 (6.8 ± 4.3, P < .001). Furthermore, the SUVmax at ratio of pre- to post-stimulation of stage 0 (1.87 ± 0.55) was significantly higher than that of stage 3 (1.16 ± 0.30, P = .001) and stage 4 (1.16 ± 0.40, P < .001).

Conclusion: This study suggests that MR sialography and SPECT/CT SUV are effective tool for the management of Sjögren's syndrome patients.

Objectives: To assess the influence of disinfecting a photostimulable phosphor plate (PSP) receptor with 0.2% peracetic acid on the vertical root fracture (VRF) diagnosis.

Methods: Baseline radiographs of 20 single-rooted teeth (10 without VRF and 10 with VRF) inserted in an alveolar socket of a human mandible were obtained with an unused PSP receptor of the Express digital system (Instrumentarium Dental Inc., Milwaukee, United States) and a Focus X-ray unit (Instrumentarium, Tuusula, Finland) set at 70 kVp, 7 mA, and an exposure time of 0.125 s. Then, 20 disinfections were performed on the PSP receptor, representing one disinfection cycle. Each disinfection lasted 30 s and the interval between them was 40 min. Subsequently, another 20 radiographs were obtained. This process occurred 9 more times, resulting in 200 disinfections (10 cycles × 20 disinfections) and 220 radiographs ([10 cycles × 20 teeth] + 20 baseline radiographs). All 220 radiographs were assessed independently by 5 examiners for VRF diagnosis. Area under the receiver operating characteristic curve (AUC), sensitivity, and specificity were calculated and compared among the number of disinfections by analysis of variance. The significance level was set at 5%. Weighted Kappa test evaluated intra- and inter-examiner agreements.

Results: The disinfections did not affect the AUC, sensitivity and specificity values for VRF diagnosis (P > 0.05). Moreover, the intra- and inter-examiner agreements ranged from moderate to perfect (0.55-1.00) and from fair to moderate (0.22-0.49), respectively.

Conclusions: Disinfecting a PSP receptor with 0.2% peracetic acid did not affect the radiographic diagnosis of VRF.

To investigate the effectiveness of Virtual Reality (VR) simulations in improving learning outcomes in dental radiology in panoramic radiography. Thirty-two volunteer dental students (first and second year of study) had the same theoretical lecture about panoramic imaging. For practical training, students were randomly divided into 2 groups: G1: traditional educational method and G2: VR (Qbion AB software). Panoramic images of 2 anthropomorphic phantoms using a VistaVoxS 3D device were acquired. The type and number of positioning errors and the need for a retake were evaluated by 1 Oral Radiology teacher and 1 senior radiographer in consensus. To test the retention of knowledge, students from both groups had to identify the absence or presence of positioning errors. Data obtained were evaluated by a descriptive analysis and it considered the frequency of the categorical variables. The positioning error rate was higher for G1 (62.50%). Type error 3 (Patient's chin raised too high) was the most prevalent (47.06%) among the groups. The retake rate among all students was similar (25%). G2 was more able to detect patient's positioning errors (68.8%) than G1. The semi-immersive VR software demonstrated potential benefits for dental students. VR tools could be integrated into Oral Radiology preclinical simulations as an additional educational tool to help reduce patient positioning errors in panoramic radiography. This study highlights the effectiveness of semi-immersive VR in improving dental students' ability to detect and prevent positioning errors in panoramic radiography. VR training enhances knowledge retention and supports its integration into preclinical education as an additional educational tool to optimize radiographic training.

Objectives: Reliable cancellous bone segmentation in Cone Beam CT (CBCT) images is essential for post-orthognathic assessment of condylar resorption. However, challenges such as edge blurring and low contrast in CBCT images make effective segmentation difficult. This study aims to overcome these issues, providing a foundation for accurate bone quantification to enhance surgical planning and patient outcomes.

Methods: We propose a novel approach to enhance edge-based segmentation for cancellous bone in CBCT images. By incorporating edge features from the cancellous bone region and utilizing cancellous edge localization as an auxiliary task via Dual-Branch Fusion Network (DBF-Net), our model leverages shared feature parameters across functions to improve segmentation accuracy and robustness.

Results: Our DBF-Net outperformed other models, achieving DICE coefficient of 91.48%. And the 95% Hausdorff Distance decreased to 3.88 mm, demonstrating significant improvement in cancellous bone boundary detection, which is crucial for the post-orthognathic assessment of condylar resorption.

Conclusion: This method provides a robust solution for reliable cancellous bone segmentation in CBCT images to support the quantitative assessment of condylar resorption.

Background: Radiographic imaging is essential in dental diagnostics, yet concerns persist regarding its genotoxic impact. While digital advancements have reduced radiation doses, the effects of X-ray exposure on oral mucosal cells remain debated. This study systematically reviews and quantitatively analyzes the effects of X-ray exposure on micronucleus (MN) formation in oral epithelial cells, examining potential age-related variations.

Methods: A thorough literature review was performed across PubMed, Web of Science, EBSCO, and Scopus (updated to November 2024), adhering to PRISMA criteria. Eligible studies examined cytogenetic changes in oral epithelial cells after X-ray exposure in healthy individuals. Data extraction covered study design, imaging modality, radiation dose, micronucleus frequency, and statistical methods. Risk of bias was assessed using a modified EPHPP tool. A random-effects model synthesized micronucleus frequency changes, and Fisher's Z-transformation analyzed age correlations.

Results: Eighteen studies met the inclusion criteria, with 16 centered on panoramic imaging and two examining a combination of CBCT and lateral cephalometric X-rays. Meta-analysis confirmed a significant increase in micronucleus frequency post-exposure (SMD = 0.30, 95% CI: 0.07-0.52, p = 0.01), indicating genotoxic effects. However, age showed a weak correlation with micronucleus formation (r = 0.149, 95% CI: -0.009 to 0.3, p = 0.065).

Conclusions: X-ray exposure induces measurable genotoxic damage in oral epithelial cells, though age-related effects remain inconclusive. Adhering to the ALARA principle is crucial to minimize unnecessary radiation. Future studies should employ larger cohorts and refined biomarkers to enhance risk assessment.

Objectives: This study aimed to investigate the vertical magnification ratios of various digital panoramic radiography devices and assess their consistency. It also examined the relationship between magnification ratios and Digital Imaging and Communications in Medicine (DICOM) header information to determine the potential use of key metadata in inferring or standardizing magnification corrections.

Methods: A ball phantom with metal spheres and an implant phantom were used to assess vertical magnification ratios. Eleven panoramic radiography systems were tested, and three DICOM tags-pixel spacing, imager pixel spacing, and aspect ratio-were analyzed. Three specialists measured phantom lengths in randomized DICOM images using PACS software, repeating measurements after 4 weeks. Magnification ratios were calculated by averaging 24 measurements per sample and comparing them to actual lengths.

Results: Intra- and interobserver reliability were high (ICC > 0.99). Most devices showed magnification ratios of 0.95-1.08, whereas those of devices 3 and 9 ranged from 1.21 to 1.30. Although some magnification ratios, which were used for system-based calibration, could be indirectly inferred by dividing the imager pixel spacing value by the pixel spacing value when both values were precisely recorded, no DICOM headers explicitly provided magnification ratios.

Conclusions: This study demonstrated that many digital panoramic radiography devices apply software-based corrections to achieve a vertical magnification ratio close to 1.0; however, inconsistencies remain across different systems. Measurement accuracy and clinical reliability can be enhanced by standardization of magnification correction methods and improved documentation in product specifications and DICOM headers, which is clinically relevant for increasing the accuracy of vertical measurements in procedures such as dental implant planning and thereby enhancing treatment predictability and patient safety.

To provide an overview of how Cone Beam Computed Tomography (CBCT) has been used in the assessment of degenerative changes of the temporomandibular joint (TMJ), with emphasis on image acquisition protocols, examiner calibration, and the criteria used for assessing and diagnosing TMJ structures. Searches were performed on PubMed, Embase, Scopus, and Web of Science databases on March 5, 2025. In vivo studies with a sample of adult individuals and which used CBCT to evaluate degenerative changes were included. Studies that did not discriminate voxel size, kV, or mA parameters and those without information on the degenerative changes assessed or the criteria used for image evaluation were excluded. Twenty-four studies were included. A wide variation in CBCT acquisition parameters was verified (voxel size varied from 0.076 mm to 0.3 mm, kV values were between 70 and 120, and mA between 3 and 38) which appear not to influence the detection of degenerative changes. The diverse criteria for CBCT assessment employed, many of which not validated, demonstrate a lack of standardization in TMJ assessment across the scientific literature. Furthermore, examiner calibration was not reported by 14 studies. Voxel size does not seem to significantly influence the detection of degenerative changes. The studies show a lack of examiner calibration, as well as inconsistencies in the standardization of acquisition parameters and evaluation protocols for CBCT imaging of the TMJ. Standardized and validated criteria are needed to enhance diagnostic accuracy and comparability among studies.

Objectives: Accurate segmentation of the maxillary sinus from medical images is essential for diagnostic purposes and surgical planning. Manual segmentation of the maxillary sinus, while the gold standard, is time consuming and requires adequate training. To overcome this problem, artificial intelligence (AI) enabled automatic segmentation software's developed. The purpose of this review is to systematically analyse the current literature to investigate the accuracy and efficiency of automatic segmentation techniques of the maxillary sinus to manual segmentation.

Methods: A systematic approach to perform a thorough analysis of the existing literature using PRISMA guidelines. Data for this study was obtained from Pubmed, Medline, Embase, and Google Scholar databases. The inclusion and exclusion eligibility criteria were used to shortlist relevant studies. The sample size, anatomical structures segmented, experience of operators, type of manual segmentation software used, type of automatic segmentation software used, statistical comparative method used, and length of time of segmentation were analysed.

Results: This systematic review presents 10 studies that compared the accuracy and efficiency of automatic segmentation of the maxillary sinus to manual segmentation. All the studies included in this study were found to have a low risk of bias. Samples sizes ranged from 3 to 144, a variety of operators were used to manually segment the cone-beam computed tomography (CBCT) and segmentation was made primarily to 3D slicer and Mimics software. The comparison was primarily made to Unet architecture softwares, with the dice-coefficient being the primary means of comparison.

Conclusions: This systematic review showed that automatic segmentation technique was consistently faster than manual segmentation techniques and over 90% accurate when compared to the gold standard of manual segmentation.

Objectives: To compare the accuracy of cone-beam CT (CBCT), ultrasonography (USG) and direct measurements in linear dimensions of periodontal defects on the buccal alveolar surfaces of mandibular sheep teeth.

Methods: A total of 88 defects were artificially created, including dehiscence, fenestration, grade I and II endodontic-periodontal defects. Two observers performed measurements twice. Maximum length, depth, and width of the defects were measured with all 3 methods. Manual measurements were accepted as the gold standard. Intraclass correlation coefficients (ICC) were calculated. The mean value of the measurements, the bias, the SD of the differences, and the limits of agreement were estimated. Statistical significance was set at P < .05.

Results: Intra- and inter-observer reliability was excellent, suggesting ICCs 0.988-1 and 0.981-1, respectively. The highest CCs were obtained from depth measurements, while the lowest CCs were obtained from length measurements. Although the differences were scattered around the bias. The estimated bias values for USG and CBCT were 0.18 (0.153-0.21) (P < .001) and 0.091 (0.079-0.102) (P < .001), respectively. Observers recorded measurements which were slightly underestimated with both techniques utilized.

Conclusions: Observers measured periodontal defects with clinically acceptable underestimations by using CBCT and USG.

Advances in knowledge: It is important to compare different innovative imaging modalities and gauge their efficiency in the measurement of various types of periodontal defects in terms of treatment planning, prognosis, and follow up of those cases.

Objectives: Due to the difference between the natural head position during scan and the orientation of CBCT display required for diagnosis, radiologists need to manually adjust the image orientation during clinical diagnosis. To eliminate this difference, this study explored orientation normalization algorithm for mandibular condyle in the small field-of-view (FoV) cone beam CT (CBCT) images.

Methods: Based on the morphology analysis, we designed principal component analysis (PCA) based orientation normalization algorithm for condyle in the small FoV CBCT images. The algorithm involves first locating the reference centre, defined as the centre coordinates of the condylar head in the maximum axial plane, through segmentation and centroid calculation. Subsequently, the maximum principal orientations in the axial, coronal, and sagittal planes are extracted using PCA algorithm. Finally, the condyle orientation is normalized by using rotation transformation matrices derived from condylar head centre localization and principal orientation extraction.

Results: Our algorithm was evaluated on 2 CBCT image datasets with 692 scans, and multiple experiments were designed from aspects of algorithm accuracy and stability. Experimental results demonstrate that images with orientation normalization are consistent with the radiologists expected perspective from both qualitative and quantitative aspects. The normalized results of CBCT images taken at multiple time-points also further confirm that our method has good stability.

Conclusion: Based on the morphological characteristics, medical image processing algorithm can achieve accurate and stable orientation normalization for condyle in the small FoV CBCT images.