Oral Radiology最新文献

Dentigerous cysts are known as the second most common type of cyst in the jaws. The cyst is one of the lesions occurred frequently in the posterior body of the mandible and is often related to the unerupted third molar and forms around the crown of the unerupted tooth attaching at the cementoenamel junction. Such characteristic appearances are the diagnostic points differentiating from ameloblastoma or odontogenic keratocyst. However, it would be hard for us to diagnose it as a dentigerous cyst if the lesion does not show its typical appearance. We experienced two cases of dentigerous cysts which did not form around the crown of the unerupted tooth on radiologically. Both cysts were relatively large and resorbed adjacent teeth roots. Therefore, an ameloblastoma or an odontogenic keratocyst was suspected rather than a dentigerous cyst as the imaging diagnosis. The biopsy revealed that the lesion was a "dentigerous cyst" in one of the cases and "developmental cyst with inflammation" in another case. After the excision, the histopathological diagnosis was a dentigerous cyst with inflammation in both cases. This report shows the two cases of dentigerous cysts focusing on panoramic radiography and CT images. Also, we discuss the differential diagnosis by reconsidering those diagnostic points.

Objectives: This systematic review on generative adversarial network (GAN) architectures for dental image analysis provides a comprehensive overview to readers regarding current GAN trends in dental imagery and potential future applications.

Methods: Electronic databases (PubMed/MEDLINE, Scopus, Embase, and Cochrane Library) were searched to identify studies involving GANs for dental image analysis. Eighteen full-text articles describing the applications of GANs in dental imagery were reviewed. Risk of bias and applicability concerns were assessed using the QUADAS-2 tool.

Results: GANs were used for various imaging modalities, including two-dimensional and three-dimensional images. In dental imaging, GANs were utilized for tasks such as artifact reduction, denoising, and super-resolution, domain transfer, image generation for augmentation, outcome prediction, and identification. The generated images were incorporated into tasks such as landmark detection, object detection and classification. Because of heterogeneity among the studies, a meta-analysis could not be conducted. Most studies (72%) had a low risk of bias in all four domains. However, only three (17%) studies had a low risk of applicability concerns.

Conclusions: This extensive analysis of GANs in dental imaging highlighted their broad application potential within the dental field. Future studies should address limitations related to the stability, repeatability, and overall interpretability of GAN architectures. By overcoming these challenges, the applicability of GANs in dentistry can be enhanced, ultimately benefiting the dental field in its use of GANs and artificial intelligence.

Objectives: Evaluate exposure and protection practices regarding dentomaxillofacial imaging among pediatric dentists in Europe and determine the effect of different clinician specific characteristics on their implementation.

Methods: A cross-sectional study involving an electronic questionnaire addressed to paediatric dentists, participating in a seminar on dental radiology organized by the European Academy of Paediatric Dentistry. Participants were asked to respond to questions regarding dentomaxillofacial imaging in terms of applied radiation dose, adoption of radiation protection techniques, and different patterns of radiographic studying and exchange between patients and colleagues. Data analysis was performed and distribution of responses was tested using chi-square and Fisher's exact tests.

Results: A total of 151 paediatric dentists, 119 females and 32 males, with a mean chronological age of 42.8 years (s.e. 11.3 years), successfully completed the questionnaire (response rate = 82%). Regardless of the type of radiograph, majority of respondents (68%), reported that they perform the radiographs themselves, while 21% reported that they refer the patients. Half of the respondents (51%), indicated requesting a small (localized) field of view (FOV) when referring for a cone beam computed tomography (CBCT) with only a small proportion (11%) reporting a large (maxillofacial) FOV. Thyroid collars and optimizing exposure settings were the most commonly reported patient protection measures used. Lastly, paediatric dentists have adopted the latest technological capacities for the study of dental images.

Conclusions: Dentomaxillofacial imaging protection and exposure protocols used are common among paediatric dentists with none of their specific characteristics having a significant effect.

We report an unusual case of carcinoma ex pleomorphic adenoma (CXPA) in the submandibular gland. The mass had a unique calcification. Panoramic tomography revealed sponge-like calcification. The central portion displayed heterogeneous high signal intensity on T1-weighted image (T1WI) and T2-weighted image (T2WI), and heterogeneously moderate signal intensity on a short-TI inversion recovery (STIR) image. The ADC was low (0.78 × 10^-3mm²/sec). After surgical excision, a pathological examination revealed that the mass contained CXPA as a minor component. Tumor cells with large hyperchromatic nuclei and eosinophilic or clear cytoplasm proliferated in irregular small tubule formations or cribriform or Roman-bridge structures in hyalinized or focally ossified stroma. The entire mass was calcified, particularly in the central region. Taken together, the reduced T1 relaxation times were related to the surface effects of diamagnetic particles, which were observed at calcium particle concentrations of up to 30%. We report a CXPA with unusual sponge-like calcification, which appeared unusually hyperintense on T1WI due to a surface effect.

Objectives: This study aimed to perform morphometric measurements of the pterygopalatine fossa (PPF), the transition zone to critical neurovascular structures. The second aim was to investigate the relationship between the volumes of the PPF and the paranasal sinuses and the effect of nasal septum deviation (NSD) types on all these measurements.

Methods: We performed PPF's morphometry and all volume measurements on the CT images of 260 patients (130 male and 130 female, age range 18-79).

Results: All volumetric measurements and the angle between foramen rotundum (FR) and pterygomaxillary fissure (PMF) were significantly higher in males than females. In contrast, the distance between sphenopalatine foramen (SPF) and PMF was considerably higher in females than in males. The PPF volume, the distance between the pterygoid canal (PC) and maxillary sinus, and the angle between FR and PMF were significantly higher on the right side than on the left. In contrast, the angle between PC and SPF and between greater palatine canal and PPF were considerably higher on the left side than on the right. The angle between PC and SPF decreased markedly with age. Only sphenoidal sinus volume was significantly smaller on the same side as the septal deviation. There was no correlation between PPF volume with maxillary and sphenoid sinus volumes from adjacent paranasal sinuses.

Conclusions: Volumetric and morphometric data obtained from PPF and paranasal sinuses can aid clinicians in diagnosing and treating patients by guiding them in selecting the right surgical approach or tools, especially in endoscopic procedures.

Objectives: This study aimed to investigate the incidence of osteonecrosis of the jawbones (ORN) after tooth extraction in patients undergoing low-dose rate brachytherapy (LDR-BT) and assess its safety.

Methods: This study retrospectively analyzed 145 patients with tongue cancer treated at Hiroshima University Hospital from 2007 to 2021 with LDR-BT using 192Ir or 198Au alone, LDR-BT and external beam radiotherapy (EBRT) with or without chemotherapy, and LDR-BT with chemotherapy. Patients' mandible and maxilla were protected with spacers. Forty-seven patients underwent tooth extraction, and the incidence, site, and relationship of ORN with tooth extraction were recorded. A subgroup of 26 patients received additional EBRT to the neck after dissection for late cervical lymph node metastases.

Results: Of 145 patients, six (4.1%) developed ORN on the same side of the mandible as LDR-BT, and EBRT was performed before and/or after LDR-BT on the sites where ORNs developed. Five of 47 (10.6%) patients who underwent tooth extraction after LDR-BT developed ORN. ORN incidence was 1.8% (2/109) in the LDR-BT and/or chemotherapy group and 11.1% (4/36) in the combination LDR-BT and EBRT and/or chemotherapy group for primary tongue cancer. Different irradiation methods (LDR-BT and/or chemotherapy and combination LDR-BT and EBRT and/or chemotherapy) and the presence or absence of tooth extraction showed significant differences (p = 0.0335 and p = 0.0139, respectively) with or without ORN.

Conclusions: Mandibular tooth extraction should be avoided on the side of LDR-BT in combined EBRT cases. However, tooth extraction is feasible using a spacer in LDR-BT and/or chemotherapy.

Introduction: In in-vitro dental radiographic research, simulation of soft tissue is required to replicate the clinical condition as close as possible. This study aimed to find out which soft tissue simulation material have been studied to use in dentomaxillofacial radiology and showed similarity in radiodensity to the soft tissues of the maxillofacial region.

Methods: In this scoping review, Web of Science, Embase, Scopus, Google scholar and PubMed databases were searched on April 9, 2023, considering the following PICOS: Population: soft tissue simulants, Intervention: X-ray-based imaging, Comparison: -, Outcome: properties of the soft tissue simulants, Study design: in-vitro studies. Screening, study selection, and data extraction were performed by two independent researchers. A third team member was consulted in the case of disagreement. Quality assessment of the included studies was made using Quality Assessment Tool For In-Vitro Studies (QUIN Tool).

Results: Of the initial 1172 articles retrieved in the database search, 13 studies were included in the review. Seven studies had a low risk of bias. In 8 studies, computed tomography (CT) or cone beam computed tomography (CBCT), in 4 studies intraoral radiography, and in 2 studies panoramic radiography was used (one study has used CT/CBCT and panoramic radiography). The studies varied in the radiographic modality, acquisition parameters, selected outcomes, and gold standard. In the majority of the studies (n = 10, 77%), acrylic resin derivatives were used in the soft tissue simulant formula alone or as a major component. Wax was used in the simulant material in 8 studies (62%). In addition, in 3 studies (23%) ice/water was used as the main simulant.

Conclusion: Ballistic gelatin, expanded 2-cm thick polystyrene with or without 1-cm utility wax, and 0.5 cm of acrylic resin were shown to have a radiographic density similar to soft tissue in standardized studies employing CBCT scanning. For intraoral radiographs, using self-polymerizing acrylic resin, utility wax, and wood, as well as a polymethylmethacrylate box filled with water in thicknesses ranging from 4 to 45 mm, provides suitable radiographic contrast. However, for 4 and 8 mm of wax and 4 mm of water, the radiographic contrast is not appropriate. In addition, 13-17 mm wax and 14.5 mm acrylic resin showed acceptable soft tissue densities in intraoral radiography. Further studies using different imaging modalities with standardized conditions and objective metrics are required to confirm the most appropriate soft tissue simulant material for in-vitro dental radiographic research.

Objectives: The present study aims to evaluate the thickness and radiological patterns of the superior semicircular canal (SSC) in patients with unilateral cleft lip and palate (CL/P).

Methods: Cone beam computed tomography (CBCT) images of the patients were evaluated in axial and Pöschl planes. CBCT images of 84 patients with unilateral CL/P and 168 healthy individual controls were included in the study. Three study groups were established: the CS-CL/P group (cleft side temporal bones of the CL/P patients), NCS-CL/P (non-cleft side temporal bones of the CL/P patients) and the control group. The radiological patterns of SSCs were categorized as dehiscence, papyraceous, normal, pneumatised and thick. The minimum bone thickness of SSC was measured.

Results: It was found that the CS-CL/P group had a higher prevalence for SSCD compared to both the NCS-CL/P group and the control group. CS-CL/P group had a higher prevalence of dehiscence type and papyraceous type compared to the control group. The SSC thickness on the CS-CL/P patients was thinner than the NCS-CL/P patients and the control group sides (p = 0.033 and p < 0.001, respectively).

Conclusions: The mean thickness of SSC was found significantly lower in the CS-CL/P group compared to both the NCS-CL/P group and the control group. The elevated prevalence of dehiscence and papyraceous types in the CS-C/LP group compared to the control group implies that the presence of a cleft may be a predisposing factor for these types.

Objectives: To evaluate the diagnostic accuracy of Fused (MRI)-CBCT images in the assessment of internal derangement of the temporomandibular joint.

Methods: MRI and CBCT images of the TMJ were evaluated bilaterally in 10 patients with clinically diagnosed internal derangement. Image fusion was performed using Amira 3D Software (version 5.4.3, Thermo Fisher Scientific Inc.).

Results: The AUC index for MRI-CBCT fused images was 0.83, which was significantly different from the null hypothesis value of 0.5. This was confirmed by inter-examiner reliability index of 0.87, which is statistically significant.

Conclusion: MRI-CBCT fused images can significantly improve the accuracy and inter-examiner reliability in the evaluation of clinically diagnosed cases with internal derangement.

Objective: The aim of this study is to compare the pre-COVID-19 and post-COVID-19 dental radiological findings of individuals with positive rRT-PCR test results and with healthy controls using the apical periodontitis grade scale (APGS), radiographic-based periodontal bone loss (R-PBL), and radiographic DMFT indices, and to investigate the relatively long-term dental effects of COVID-19.

Methods: This study included people who had two panoramic radiographs taken between 2018 and 2022. There are 52 patients with positive rRT-PCR tests in the study group. The control group included 50 individuals. Study and control groups were compared using the apical periodontitis grade scale (APGS), radiographic-based periodontal bone loss (R-PBL), and radiographic DMFT indices.

Results: Although results showed a significant difference in percentage R-PBL value and R-PBL types in the study group, there was no significant difference in percentage R-PBL value and R-PBL types in the control group. Also, both groups showed a significant difference in the DMFT index.

Conclusions: According to the results of this study, it can be said that COVID-19 increases the incidence of periodontitis, and it can be interpreted that the pandemic may adversely affect the general oral health of all people.