Oral Radiology最新文献_第2页

Arteriovenous fistula of the mandible: a case report. 下颚动静脉瘘：病例报告。

IF 1.6 3区医学

Oral Radiology Pub Date : 2024-10-01 Epub Date: 2024-06-19 DOI: 10.1007/s11282-024-00762-6

Mattia Todaro, Ermal Pashaj, Alessandro Pedicelli, Andrea Alexandre, Gianmarco Saponaro, Giulio Gasparini, Alessandro Moro

引用次数: 0

Deep learning classification performance for diagnosing condylar osteoarthritis in patients with dentofacial deformities using panoramic temporomandibular joint projection images. 利用颞下颌关节全景投影图像诊断颌面部畸形患者髁状突骨关节炎的深度学习分类性能。

IF 1.6 3区医学

Oral Radiology Pub Date : 2024-10-01 Epub Date: 2024-07-11 DOI: 10.1007/s11282-024-00768-0

Yukiko Iwase, Tomoya Sugiki, Yoshitaka Kise, Masako Nishiyama, Michihito Nozawa, Motoki Fukuda, Yoshiko Ariji, Eiichiro Ariji

{"title":"Deep learning classification performance for diagnosing condylar osteoarthritis in patients with dentofacial deformities using panoramic temporomandibular joint projection images.","authors":"Yukiko Iwase, Tomoya Sugiki, Yoshitaka Kise, Masako Nishiyama, Michihito Nozawa, Motoki Fukuda, Yoshiko Ariji, Eiichiro Ariji","doi":"10.1007/s11282-024-00768-0","DOIUrl":"10.1007/s11282-024-00768-0","url":null,"abstract":"Objective: The present study aimed to assess the consistencies and performances of deep learning (DL) models in the diagnosis of condylar osteoarthritis (OA) among patients with dentofacial deformities using panoramic temporomandibular joint (TMJ) projection images.Methods: A total of 68 TMJs with or without condylar OA in dentofacial deformity patients were tested to verify the consistencies and performances of DL models created using 252 TMJs with or without OA in TMJ disorder and dentofacial deformity patients; these models were used to diagnose OA on conventional panoramic (Con-Pa) images and open (Open-TMJ) and closed (Closed-TMJ) mouth TMJ projection images. The GoogLeNet and VGG-16 networks were used to create the DL models. For comparison, two dental residents with < 1 year of experience interpreting radiographs evaluated the same condyle data that had been used to test the DL models.Results: On Open-TMJ images, the DL models showed moderate to very good consistency, whereas the residents' demonstrated fair consistency on all images. The areas under the curve (AUCs) of both DL models on Con-Pa (0.84 for GoogLeNet and 0.75 for VGG-16) and Open-TMJ images (0.89 for both models) were significantly higher than the residents' AUCs (p < 0.01). The AUCs of the DL models on Open-TMJ images (0.89 for both models) were higher than the AUCs on Closed-TMJ images (0.72 for both models).Conclusions: The DL models created in this study could help residents to interpret Con-Pa and Open-TMJ images in the diagnosis of condylar OA.","PeriodicalId":56103,"journal":{"name":"Oral Radiology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141581652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Correction: Radiologic evaluation of associated symptoms and fractal analysis of unilateral dens invaginatus cases. 更正：相关症状的放射学评估和单侧颅内凹陷病例的骨折分析。

IF 1.6 3区医学

Oral Radiology Pub Date : 2024-10-01 DOI: 10.1007/s11282-024-00760-8

Sema Kaya, Alaettin Koc

引用次数: 0

Comparing the accuracy of two machine learning models in detection and classification of periapical lesions using periapical radiographs. 比较两种机器学习模型使用根尖周X光片检测和分类根尖周病变的准确性。

IF 1.6 3区医学

Oral Radiology Pub Date : 2024-10-01 Epub Date: 2024-06-11 DOI: 10.1007/s11282-024-00759-1

Do Hoang Viet, Le Hoang Son, Do Ngoc Tuyen, Tran Manh Tuan, Nguyen Phu Thang, Vo Truong Nhu Ngoc

{"title":"Comparing the accuracy of two machine learning models in detection and classification of periapical lesions using periapical radiographs.","authors":"Do Hoang Viet, Le Hoang Son, Do Ngoc Tuyen, Tran Manh Tuan, Nguyen Phu Thang, Vo Truong Nhu Ngoc","doi":"10.1007/s11282-024-00759-1","DOIUrl":"10.1007/s11282-024-00759-1","url":null,"abstract":"Background: Previous deep learning-based studies were mainly conducted on detecting periapical lesions; limited information in classification, such as the periapical index (PAI) scoring system, is available. The study aimed to apply two deep learning models, Faster R-CNN and YOLOv4, in detecting and classifying periapical lesions using the PAI score from periapical radiographs (PR) in three different regions of the dental arch: anterior teeth, premolars, and molars.Methods: Out of 2658 PR selected for the study, 2122 PR were used for training, 268 PR were used for validation and 268 PR were used for testing. The diagnosis made by experienced dentists was used as the reference diagnosis.Results: The Faster R-CNN and YOLOv4 models obtained great sensitivity, specificity, accuracy, and precision for detecting periapical lesions. No clear difference in the performance of both models among these three regions was found. The true prediction of Faster R-CNN was 89%, 83.01% and 91.84% for PAI 3, PAI 4 and PAI 5 lesions, respectively. The corresponding values of YOLOv4 were 68.06%, 50.94%, and 65.31%.Conclusions: Our study demonstrated the potential of YOLOv4 and Faster R-CNN models for detecting and classifying periapical lesions based on the PAI scoring system using periapical radiographs.","PeriodicalId":56103,"journal":{"name":"Oral Radiology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141307539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Developing evidence-based clinical imaging guidelines for the diagnosis of vertically fractured teeth. 为诊断牙齿垂直折断制定循证临床成像指南。

IF 1.6 3区医学

Oral Radiology Pub Date : 2024-10-01 Epub Date: 2024-07-08 DOI: 10.1007/s11282-024-00766-2

Ki-Hong Kim, Jo-Eun Kim, Sam-Sun Lee, Chena Lee, Miyoung Choi, Hwan Seok Yong, Seung Eun Jung, Min-Suk Heo, Kyung-Hoe Huh

{"title":"Developing evidence-based clinical imaging guidelines for the diagnosis of vertically fractured teeth.","authors":"Ki-Hong Kim, Jo-Eun Kim, Sam-Sun Lee, Chena Lee, Miyoung Choi, Hwan Seok Yong, Seung Eun Jung, Min-Suk Heo, Kyung-Hoe Huh","doi":"10.1007/s11282-024-00766-2","DOIUrl":"10.1007/s11282-024-00766-2","url":null,"abstract":"Objectives: This study aimed to develop an evidence-based clinical imaging guideline for teeth suspected with vertical root fractures.Methods: An adaptation methodology based on the Korean Clinical Imaging Guidelines (K-CIG) was used in the guideline development process. After searching for guidelines using major databases such as Ovid-Medline, Elsevier-Embase, National Guideline Clearinghouse, and Guideline International Network, as well as domestic databases such as KoreaMed, KMbase, and KoMGI, two reviewers analyzed the retrieved articles. The retrieved articles were included in this review using well-established inclusion criteria.Results: Twenty articles were identified through an online search, of which three were selected for guideline development. Based on these three guidelines, this study developed specific recommendations concerning the optimal imaging modality for diagnosing teeth suspected of vertical root fractures.Conclusions: Periapical radiography is the preferred method for assessing teeth with mastication-related pain and suspected vertical root fractures. However, if intraoral radiographs do not provide sufficient information about root fractures, a small FOV CBCT may be considered. However, the use of CBCT in endodontically treated teeth is significantly constrained by the presence of artificial shading.","PeriodicalId":56103,"journal":{"name":"Oral Radiology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11379765/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141556067","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Radiologic evaluation of associated symptoms and fractal analysis of unilateral dens invaginatus cases. 相关症状的放射学评估和单侧颅内凹陷病例的骨折分析。

IF 1.6 3区医学

Oral Radiology Pub Date : 2024-10-01 Epub Date: 2024-05-15 DOI: 10.1007/s11282-024-00756-4

Sema Kaya, Alaettin Koc

{"title":"Radiologic evaluation of associated symptoms and fractal analysis of unilateral dens invaginatus cases.","authors":"Sema Kaya, Alaettin Koc","doi":"10.1007/s11282-024-00756-4","DOIUrl":"10.1007/s11282-024-00756-4","url":null,"abstract":"Objective: The aim of this study is to determine the age-based prevalence of dens invaginatus cases and to learn the radiologic findings. In addition, fractal analysis of the periapical regions of unilateral dens invaginatus cases and contralateral teeth was performed to determine the effect of possible microleakage on fractal dimension.Methods: A total of 136 patients (170 teeth) identified in panoramic radiographs taken for diagnostic purposes between January 2018 and December 2023 at our Department of Oral and Maxillofacial Radiology were included in the study. Data were analysed using IBM SPSS V23. The Chi-square test was used for comparing categorical variables between groups. The relationship between the FD values calculated around the apexes of the teeth with unilateral dens invaginatus and the contralateral teeth was analyzed by paired t test. A significance level of p < 0.050 was adopted.Results: The mean age of the cases was calculated as 28.1 (8-63) years. 66 (48.5%) of the cases were female, and 70 (51.1%) were male. The lateral incisor was the most affected tooth among these cases. Bilateral cases were observed in 34 patients. Type 2 was detected in 93 patients, Type 1 in 35 patients, and Type 3 dens invagination in 8 patients. Dens invaginatus cases were observed in 134 maxillary and 2 mandibular teeth. Periapical lesions were seen in 22 of these cases.Conclusions: Dens invaginatus cases are a congenital anomaly encountered at any age. Early diagnosis is crucial to prevent the loss of pulp vitality due to these invaginations. It should be noted that these invaginations can affect both jaws. However, due to the prevalence of occurrence in the maxillary anterior teeth and asymptomatic nonvitality, particular attention should be paid to evaluating this region.","PeriodicalId":56103,"journal":{"name":"Oral Radiology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140923466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Central dentinogenic ghost cell tumor of the maxilla: a case report with new imaging findings and review of the literature. 上颌骨中心性牙本质鬼细胞瘤：病例报告、新的影像学发现和文献综述。

IF 1.6 3区医学

Oral Radiology Pub Date : 2024-10-01 Epub Date: 2024-07-05 DOI: 10.1007/s11282-024-00764-4

Suzuka Yoshida, Yohei Takeshita, Toshiyuki Kawazu, Miki Hisatomi, Shunsuke Okada, Mamiko Fujikura, Kyoichi Obata, Kiyofumi Takabatake, Saori Yoshida, Junichi Asaumi

{"title":"Central dentinogenic ghost cell tumor of the maxilla: a case report with new imaging findings and review of the literature.","authors":"Suzuka Yoshida, Yohei Takeshita, Toshiyuki Kawazu, Miki Hisatomi, Shunsuke Okada, Mamiko Fujikura, Kyoichi Obata, Kiyofumi Takabatake, Saori Yoshida, Junichi Asaumi","doi":"10.1007/s11282-024-00764-4","DOIUrl":"10.1007/s11282-024-00764-4","url":null,"abstract":"A dentinogenic ghost cell tumor (DGCT) is a rare benign odontogenic tumor that commonly shows characteristics of solid proliferation and has a relatively high risk of recurrence after surgical treatment. We herein report a case of a central DGCT that occurred in the maxilla and resulted in bone expansion. This study highlights new imaging findings (particularly magnetic resonance imaging) along with histopathological observations. In addition, we conducted a review of the existing literature on this rare tumor. A 37-year-old man developed swelling around the right cheek. A benign odontogenic tumor such as ameloblastoma was suspected based on the imaging examination findings (including bone expansion and the internal characteristics of the tumor) on panoramic imaging, computed tomography, and magnetic resonance imaging. The lesion was surgically excised from the right maxilla. Postoperative histopathological examination led to a definitive diagnosis of central DGCT. The tumor comprised epithelial neoplastic islands, resembling ameloblastoma, inside tight fibroconnective tissue; masses of ghost cells and formation of dentin were also observed. We had suspected that the minute high-density region around the molars on the imaging examinations represented alveolar bone change; however, it represented dentin formation. This led to difficulty diagnosing the lesion. Although DGCT may present characteristic findings on imaging examinations, its occurrence is infrequent, and in some cases, the findings may include the presence or absence of an impacted tooth without obvious calcification. The present case suggests that we should consider the possibility of an odontogenic tumor with calcification when high-density structures are observed inside the lesion.","PeriodicalId":56103,"journal":{"name":"Oral Radiology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11379793/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141538996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spread asymmetry to differentiate nasopalatine duct cysts from radicular cysts arising in the anterior maxilla on computed tomographic images. 通过计算机断层扫描图像上的不对称扩散来区分鼻腭管囊肿和上颌骨前部的根状囊肿。

IF 1.6 3区医学

Oral Radiology Pub Date : 2024-10-01 Epub Date: 2024-06-18 DOI: 10.1007/s11282-024-00761-7

Haruka Ikeda, Natsuho Takata, Yoshitaka Kise, Kaori Ebata, Mizuho Mori, Chiaki Kuwada, Masako Nishiyama, Yukiko Iwase, Yo Ninagawa, Munetaka Naitoh, Eiichiro Ariji

{"title":"Spread asymmetry to differentiate nasopalatine duct cysts from radicular cysts arising in the anterior maxilla on computed tomographic images.","authors":"Haruka Ikeda, Natsuho Takata, Yoshitaka Kise, Kaori Ebata, Mizuho Mori, Chiaki Kuwada, Masako Nishiyama, Yukiko Iwase, Yo Ninagawa, Munetaka Naitoh, Eiichiro Ariji","doi":"10.1007/s11282-024-00761-7","DOIUrl":"10.1007/s11282-024-00761-7","url":null,"abstract":"Objective: The aim of this study was to clarify numerical values for differentiating nasopalatine duct cysts (NPDCs) from radicular cysts (RCs) arising in the anterior maxilla on computed tomography (CT) or cone-beam CT (CBCT) images.Methods: CT or CBCT images of histologically proven NPDCs (n = 30) and RCs (n = 33) beyond the midline of the maxilla were investigated to determine two asymmetry indices on axial images of the maximum lesion area. The lateral asymmetry index was calculated based on two distances from each of the lateral ends of the lesion to the midsagittal plane. The index was defined as the difference between the two distances divided by their sum. The labio-palatal asymmetry index was determined by the distance between the labial and palatal ends of the lesion and the coronal plane passing through the central incisor root apex. The performance of these indices was assessed by receiver operating characteristic (ROC) analysis. The cutoff values for differentiating NPDCs from RCs were determined with the Youden procedure on the ROC curve.Results: The area under the ROC curve was 0.97 for the lateral asymmetry index and 0.88 for the labio-palatal asymmetry index. The cutoff values for differentiation were 0.36 and 0.68 for the lateral and labio-palatal asymmetry indices, respectively.Conclusion: The lateral asymmetry index appeared to be an effective reference for differentiating NPDCs from RCs on CT or CBCT images. When the index was less than the cutoff value, a diagnosis of NPDC was strongly suggested.","PeriodicalId":56103,"journal":{"name":"Oral Radiology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141422026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparative analysis of clinical image evaluation charts for panoramic radiography. 全景放射摄影临床图像评估图表的比较分析。

IF 1.6 3区医学

Oral Radiology Pub Date : 2024-10-01 Epub Date: 2024-07-08 DOI: 10.1007/s11282-024-00765-3

Yeonhee Kim, Samsun Lee, Gyudong Jo, Ahyoung Kwon, Juhee Kang, Joeun Kim, Kyunghoe Huh, Wonjin Yi, Minsuk Heo, Soonchul Choi

{"title":"Comparative analysis of clinical image evaluation charts for panoramic radiography.","authors":"Yeonhee Kim, Samsun Lee, Gyudong Jo, Ahyoung Kwon, Juhee Kang, Joeun Kim, Kyunghoe Huh, Wonjin Yi, Minsuk Heo, Soonchul Choi","doi":"10.1007/s11282-024-00765-3","DOIUrl":"10.1007/s11282-024-00765-3","url":null,"abstract":"Objective: To compare and analyze professional (P chart) and simple (S chart) clinical image evaluation charts for evaluating panoramic radiograph image quality.Methods: Ten evaluators assessed 285 clinical panoramic radiograph images. The evaluators were divided into oral and maxillofacial radiologists (OMFR, n = 5) and general dentist (dentists not specializing in oral and maxillofacial radiology, G, n = 5) groups. For image evaluation, P and S charts provided by the Korean Academy of Oral and Maxillofacial Radiology were used. Scores of items for each evaluation chart were used to compare the reliability, correlation, evaluation scores, evaluation time, and preference, and statistical analyses were performed using IBM SPSS Statistics.Results: The S chart showed similar levels of evaluation scores at shorter evaluation time, as compared to the P chart. In the results for each evaluation chart, all analyzed correlations were statistically significant. Total score, image density/contrast/sharpness, and overall image quality items showed a very high positive correlation in the P chart. While the overall range of correlation coefficients was relatively lower in the S chart than the P chart, the same items showed high correlation coefficients. In the preference evaluation, both the professional and generalist groups preferred the S chart.Conclusions: A comparative analysis with the P chart, revisions, and upgrades are needed for the S chart items that showed low correlations in this study, such as artifacts, coverage area, and patient movement.","PeriodicalId":56103,"journal":{"name":"Oral Radiology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11379777/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141560456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation of masticatory muscles in patients with different sagittal direction skeletal anomalies by ultrasonography and ultrasonographic elastography. 通过超声波和超声波弹性成像评估不同矢状向骨骼异常患者的咀嚼肌。

IF 1.6 3区医学

Oral Radiology Pub Date : 2024-09-26 DOI: 10.1007/s11282-024-00774-2

Cansu Tüfekçi, Esra Bolat Gümüş, Sevcihan Günen Yılmaz

{"title":"Evaluation of masticatory muscles in patients with different sagittal direction skeletal anomalies by ultrasonography and ultrasonographic elastography.","authors":"Cansu Tüfekçi, Esra Bolat Gümüş, Sevcihan Günen Yılmaz","doi":"10.1007/s11282-024-00774-2","DOIUrl":"https://doi.org/10.1007/s11282-024-00774-2","url":null,"abstract":"Objectives: The aim of this study was to evaluated the masseter, anterior digastric and geniohyoid muscles of individuals with similar growth and developmental periods but different sagittal skeletal malocclusions using ultrasonography and ultrasonographic elastography and to make interclass assessments.Methods: In this study, ultrasonography and ultrasonographic elastography records of 30 Class I individuals (17 females, 13 males), 30 Class II individuals (14 females, 16 males), and 27 Class III individuals (12 females, 15 males) in the normodivergent and growth development period were used. The masseter, anterior digastric, and geniohyoid muscles of individuals were examined using ultrasonography and ultrasonographic elastography, and comparisons were made between the classes. Statistical analysis was accomplished by Mann Whitney U, One-way ANOVA, Kruskal Wallis H tests.Results: Interclass differences were found in ultrasonography and elastography measurements of the masseter muscle. However, no differences were observed in ultrasonography measurements of the auxiliary masticatory muscles, whereas differences were seen only in the geniohyoid muscle in elastography measurements among the classes (p < 0.05).Conclusion: Individuals with different sagittal skeletal malocclusions during growth and development exhibited similar muscle sizes and elasticities, approximately close to each other.","PeriodicalId":56103,"journal":{"name":"Oral Radiology","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142333156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0