Oral Radiology最新文献

Objectives: This study aimed to develop and evaluate a deep convolutional neural network (CNN) model for the automatic segmentation of foreign bodies and ghost images in panoramic radiographs (PRs), which can complicate diagnostic interpretation.

Methods: A dataset of 11,226 PRs from four devices was annotated by two radiologists using the Computer Vision Annotation Tool. A U-Net-based CNN model was trained and evaluated using Intersection over Union (IoU), Dice coefficient, accuracy, precision, recall, and F1 score.

Results: For foreign body segmentation, the model achieved validation Dice and IoU scores of 0.9439 and 0.9043, and test scores of 0.9657 and 0.9371. For ghost image segmentation, validation Dice and IoU were 0.8234 and 0.7388, with test scores of 0.8749 and 0.8145. Overall test accuracy exceeded 0.999.

Conclusions: The AI model showed high accuracy in segmenting foreign bodies and ghost images in PRs, indicating its potential to assist radiologists. Further clinical validation is recommended.

Objectives: To estimate the impact of different dental impression materials on cone beam computed tomography (CBCT) metal artifacts at different resolutions and fields of view (FOVs).

Methods: A mandible model with restored human teeth was created. Six dental materials were molded as teeth overlays with uniform thickness: A-silicones (Elite HD + , and Vonflex S Putty), Alginate (Tropicalgin), Pink wax (MBwax1), C-Silicon (Zetaplus) and Zinc-oxide (COE-PAK). The model alone (control) and with teeth covered with each material was scanned using CBCT Unite KAVO dent at two different FOVs-5 × 5 (S) and 6 × 8 cm (M), and three different resolutions: low (0.28-S; 0.32-M), standard (0.20-S; 0.30-M), and high (0.125-S; 0.20-M). Two experienced radiologists analyzed a single representative view of each dataset in ImageJ quantitatively-by conducting a histogram analysis within the selected regions of interest (ROI) and qualitatively (using a five-point Likert scale). The data were analyzed using standard one-way analysis of variance (ANOVA). Inter-rater reliability was examined.

Results: The intraclass correlation coefficient for all quantitative measurements was between 0.806 and 0.996. Within FOV S, Vonflex S Putty showed significantly lower variance and range in grayscale values compared to the control at all resolution levels, while Zetaplus followed the same trend only at low resolution. As for FOV M, none of the tested materials significantly differed from the control in both variance and range. The qualitative analysis showed no significant differences when using overlays in comparison with uncovered teeth.

Conclusions: Although without significant improvements in the image quality, covering teeth with dental materials quantitatively reduced artifacts.

Objectives: This study evaluates the potential of pulp volume/total tooth-volume measurements of canine teeth in relation to chronologic age in patients with cleft lip and palate (CLP). The significance of this study lies in its exploration of the usability of these measurements for age determination in CLP patients, providing a novel perspective to the existing literature.

Methods: Cone beam computed tomography images of 33 patients (16 females, 17 males) with unilateral CLP aged 14-45 years and 33 age- and sex-matched healthy individuals (16 females, 17 males) were retrospectively evaluated. Using ITK-SNAP software, pulp and whole tooth volumes of canine teeth on the non-defect side of CLP patients and the corresponding side of healthy individuals were measured. Their relationship with chronologic age was evaluated, and comparisons were made between the CLP and control groups.

Results: No statistically significant difference was observed between the whole tooth volume, pulp volume, and pulp volume/total tooth-volume ratios of the control and CLP groups. A paired t test comparing chronologic age and calculated mean age of both groups found no significant difference.

Conclusions: The results show that the pulp and total tooth-volume ratios of canine teeth in the non-defect areas of individuals with unilateral CLP correlate with chronologic age and can be used reliably for age determination. This indicates that individuals with CLP can be evaluated similarly to healthy individuals, allowing accurate age estimation based on dental measurements.

Objectives: To assess the influence of a handheld X-ray unit in the diagnosis of proximal caries lesions using different digital systems by comparing with a wall-mounted unit.

Methods: Radiographs of 40 human teeth were acquired using the Eagle X-ray handheld unit (Alliage, São Paulo, Brazil) set at 2.5 mA, 60 kVp and an exposure time of 0.45 s. Then, new radiographs of the teeth were acquired using the Focus X-ray wall-mounted unit (Instrumentarium, Tuusula, Finland) set at 7 mA, 60 kVp, and exposure time of 0.16 s. Three digital systems were used: a photostimulable phosphor plate receptor (Express system) and two complementary metal oxide semiconductor sensors (Digora Toto and SnapShot systems). Five oral and maxillofacial radiologists individually assessed the radiographs. Area under the receiver-operating characteristic curve (AUC), sensitivity, and specificity were calculated from the responses of the examiners and compared using Analysis of Variance at a significance level of 5%. The weighted Kappa index evaluated the intra- and inter-examiner agreements for caries lesions diagnosis.

Results: The handheld X-ray unit did not influence on the diagnostic metrics for the three digital systems used when compared with the wall-mounted unit (p > 0.05). The SnapShot showed higher AUC value than Digora Toto (p < 0.05). The mean values of intra- and inter-examiner agreements were 0.654 (substantial) and 0.365 (fair), respectively.

Conclusions: The diagnostic accuracy for detecting proximal caries lesions is not influenced by the use of a handheld X-ray unit, regardless of the digital system used.

Objectives: This study aims to compare the image processing times of dental cone beam CT (CBCT) images using a remote medical image processing workstation (RW) versus on-premises image processing (OP) and assess its impact on workflow efficiency.

Methods: Data from 100 CBCT cases were randomly selected and processed using the OP3D VISION 17-19DX (EH Japan Co., Ltd.). In the OP environment, OnDemand 3D Dental (Cybermed Inc.) was used on a local terminal, while the RW setup involved a remote workstation-ZIO STATION (Ziosoft Inc.) connected via a 2 Gbps network. Seven experienced dentists processed the same data in both environments, and various processing times, including data transfer, re-slicing, 3D reconstruction, and PACS transfer, were compared.

Results: The RW environment showed significantly shorter data transfer and re-slicing times than the OP environment. However, 3D image reconstruction times were similar between the two setups. Overall, processing time was significantly reduced in the RW environment. Variability in processing times among operators was observed, with most achieving reductions in the RW environment.

Conclusions: Remote processing of dental CBCT images using a dedicated image processing device offers equivalent or improved performance compared to on-premises processing. This approach can enhance workflow efficiency by reducing processing times and freeing up local resources, although further research is needed to optimize remote display protocols and multi-client access.

Objectives: This study aimed to assess the occurrence and morphological features of the mastoid emissary foramen (MEF) using multidetector computed tomography (MDCT) images. The analysis highlights the clinical significance of these structures and their implications for surgical procedures.

Methods: A total of 357 patients were evaluated using MDCT in bone window mode with a high-resolution technique (1 mm). The presence, number, and mean diameter of the MEFs were recorded. Statistical analyses compared data between both sides and sexes.

Results: 714 sides from 357 patients (177 male, 180 female) were analyzed. The patients' ages ranged from 7 to 83 years, with a mean age of 25.6. MEFs were found in 329 patients, representing 92.15% of the total. The diameters of the MEFs ranged from 0.6 mm to 5.0 mm on the right side (mean 1.80 mm) and from 0.6 mm to 4.4 mm on the left side (mean 1.96 mm). Up to 3 MEFs were identified on the right side, and a maximum of 6 on the left. No significant differences in MEF presence were observed between sexes or between the left and right sides (p > 0.05).

Conclusion: This study reveals a high prevalence and notable anatomical variations in the MEF, with MEFs larger than previously reported. At least one MEF was detected in 92.15% of cases, emphasizing the importance of comprehensive preoperative evaluation.

Objectives: This study aimed to compare the thickness and stiffness of the masseter, anterior temporalis, and sternocleidomastoid muscles of patients diagnosed with myofascial temporomandibular disorders (TMD) pain to those of a control group.

Methods: This was a cross-sectional study conducted at a single center. Twenty-five patients diagnosed with myofascial TMD pain and 29 asymptomatic controls (Control Group) matched by age and sex were recruited. B-mode ultrasonography and shear wave elastography were used to measure the thickness and stiffness of the bilateral masseter, temporalis, and sternocleidomastoid muscles. All measurements were performed while resting and clenching. Patients were systematically evaluated for pain intensity and maximum mouth opening.

Results: There were no differences between groups in the resting and clenching thickness of any muscles (p > 0.05). There were no differences in the stiffness of the measured muscles at rest and clench between the groups, except for the masseter (p > 0.05). Individuals with myofascial TMD pain showed higher median stiffness in the right (p < 0.001) and left (p = 0.003) masseter muscles during clenching (but not during resting) compared with controls.

Conclusions: Clenching masseter stiffness was greater in individuals with myofascial TMD pain than in asymptomatic controls. These findings might help to understand the jaw biomechanics and dysfunction of individuals with myofascial TMD pain.

Objectives: To evaluate the role of computed tomography (CT)/cone-beam computed beam CT (CBCT) in association with hypoesthesia of the mental region and lower lip during the surgical removal of DCs.

Methods: A retrospective cohort study was performed involving 39 impacted mandibular DC cases between February 2011 and March 2022. We studied the association of hypoesthesia in relation to the age and sex of the patient and to growth direction and expansion of the DC on the CT/CBCT image findings. The preoperative CT/CBCT image findings were statistically analyzed in accordance with diagnoses of DCs confirmed based on pathology. Fisher's exact test was used to test the relationship between hypoesthesia and CT/CBCT imaging findings. In addition, PubMed and PubMed Central were searched using keywords such as "hypoesthesia" to find relevant studies. Reports of hypoesthesia of the mental region and lower lip were derived from the selected literature.

Results: The frequency of hypoesthesia recorded was 35.9%. No statistically significant association was observed for all hypoesthesia and CT/CBCT image findings.

Conclusions: Imaging evaluation was performed in 39 dentigerous cysts, and a literature review was performed. We found that CT/CBCT alone does not provide sufficiently reliable images required for predicting nerve lesions. Future prospective studies are required.

Objectives: The current study was conducted to assess the volume of the tongue, oral cavity, and tongue/oral cavity and their correlation with the volume of the upper airway in cleft subjects compared with the control group.

Methods: The study population included 60 CBCT images from dental school. The sample comprised 30 unilateral cleft patients and 30 sex and age-matched healthy subjects. The CBCT images were imported to the Mimics software in DICOM format. Then, the segmentation process was done in order to create distinct masks for the upper airway, oral cavity, and tongue. The software calculated the volume of the created masks.

Results: The volume of tongue, oral and upper airway were significantly lower in cleft patients than in the control group (P value < 0.05 taken as statistically significant). There was a weak but statistically significant correlation between the U.A.W.V and T.V in both cleft and non-cleft subjects. Additionally, there was a statistically significant correlation between the O.C.V and the U.A.W.V in cleft subjects.

Conclusions: Except than the proportion of tongue/oral cavity volume, other volumetric measurements were significantly lower in cleft subjects than control group. This reveals that clefts are not necessarily more susceptible to obstructive sleep apnea. Also, the positive correlation between the volume of the tongue and oral cavity with the upper airway confirms that early expansion of the maxillary region in clefts helps significantly in increasing their upper airway volume.

Background: There has been an increasing interest in the use of implants to treat edentulous patients. In this regard, the use of cone beam computed tomography (CBCT) offers a variety of advantages compared with other imaging methods. However, the creation of beam-hardening artifacts adversely affects the quality of images. To our knowledge, little is known about the actual effectiveness of the Metal Artifact Reduction (MAR) algorithm on image quality improvement.

Objectives: The objective of this study is to conduct a systematic review to investigate the effectiveness of the MAR algorithm on the magnitude of artifacts generated in CBCT images.

Materials and methods: An electronic search was performed in electronic databases, including PubMed, Scopus, Web of Science, and Google Scholar. For each database, the search strategy was defined specifically. Studies that had the inclusion criteria for this review were imported into Endnote version 20. The risk of bias in the studies included in this systematic review was assessed by two independent reviewers based on the Joanna Briggs Institute (JBI)'s Critical Appraisal checklist. The selected final articles were scored based on the specified checklist. After reviewing selected articles, it was not possible to perform a meta-analysis due to the heterogeneity and multiplicity of the variables, and the studies were included in the systematic review.

Results: A total of 4738 studies were identified. After eliminating duplicate and unrelated articles, 10 articles met the inclusion criteria. Results showed that the use of the MAR algorithm in the preparation of CBCT scans reduces the standard deviation (SD) of gray values. However, no definite result was achieved in relation to the contrast-to-noise ratio (CNR). In fact, it cannot be definitively concluded whether the use of the MAR algorithm will increase the CNR.

Conclusion: The results of this systematic review demonstrated that we cannot provide a definite answer regarding the effect of the MAR algorithm on reducing the artifacts around dental implants. The explanation is that this factor is affected by many variables, whose change can have a significant effect on the magnitude of artifacts generated in the image.