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Knowledge and Practices of Dentists, Oral and Maxillofacial Surgeons of Cone Beam Computed Tomography (CBCT) and the Dentascanner in a Low Income Country: Case of Togo
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作者 Mazamaesso Tchaou Haréfétéguéna Bissa +7 位作者 Plaodesina Essobozou Pegbessou Abdoulatif Amadou Bidamin N’timon Mawuena Dansou Abdoul-Razakou Adam Lantam Sonhaye Lama-Kegdigoma Agoda-Koussema Komlan Adjenou 《Open Journal of Radiology》 2017年第1期1-8,共8页
Background: In dental-maxillofacial imaging, 3D sectional imaging progressively replaces conventional 2D imaging in developed countries. They are based specially on Computed tomography (CT-Scan), with the Dentascan ap... Background: In dental-maxillofacial imaging, 3D sectional imaging progressively replaces conventional 2D imaging in developed countries. They are based specially on Computed tomography (CT-Scan), with the Dentascan application and cone beam computed tomography (CBCT). In developing countries those technics are newly introduced. Aim: This study aimed at studying the knowledge and practices of dentist and oral and maxillofacial surgeons on sectional imaging such as Dentascan and Cone Beam Computed Tomography (CBCT). Materials and Methods: We conducted an anonymous survey among dentists and oral maxillofacial surgeons in Togo over one month. Results: The response rate was 78.79% (27/33). They were mainly male sex (sex ratio of 2.25 men for one woman). They were aged between 27 and 71 years old with an average of 49.69 years old. The majority (61.54%) had a professional experience over 20 years. The majority of respondents (65.38%) believed their level of knowledge about dental x-Ray was poor. Half of them (50%) confirmed that they had never asked for a Dentascan, and 15.38% asked from time to time for it and only two (7.69%) asked often for this test. 96.15% confirm they have no knowledge of the Dentascan. Regarding the CBCT, 84.62% didn’t ask for it because this technique did not exist in Togo before. 69.20% of respondents confessed to be interested in continuing training on sectional imaging. Conclusion: This study shows that sectional imaging is very little used by oral and dental practitioners in Togo because of the ignorance of the new techniques and the absence of the CBCT. It is therefore necessary to promote the teaching of the new technique of sectional imaging in the training syllabus of oral and dental specialists and to initiate continuing medical training. 展开更多
关键词 KNOWLEDGE Practice Dentascan cone beam computed tomography (cbct) DENTIST Oral and Maxillofacial Surgeon TOGO
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Application of cone beam computed tomography in facial imaging science
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作者 Zacharias Fourie Janalt Damstra 《上海口腔医学》 CAS CSCD 北大核心 2012年第2期220-231,共12页
Facial imaging is used to study the facial shapeand its developmental changes over time.This isimportant to diagnose acquired malformations,to studynormal and abnormal growth and to differentiatebetween the results of... Facial imaging is used to study the facial shapeand its developmental changes over time.This isimportant to diagnose acquired malformations,to studynormal and abnormal growth and to differentiatebetween the results of treatment and normal growth,and to validate facial recognition.The two mainmethods to study and record facial imaging are bymeans of cephalometry and anthropometry[1].Cephalometrics is the scientific study of themeasurements of the 展开更多
关键词 口腔医学 临床分析 患者 症状
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Cone beam computed tomographic analyses of alveolar bone anatomy at the maxillary anterior region in Chinese adults 被引量:16
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作者 Zhixuan Zhou Wu Chen +3 位作者 Ming Shen Chao Sun Jun Li Ning Chen 《The Journal of Biomedical Research》 CAS 2014年第6期498-505,共8页
To provide an anatomical basis for clinical implant esthetics,we evaluated the morphology of the nasopalatine canal(NPC) and analyzed labial and interproximal bone anatomy at the maxillary anterior region.We sought ... To provide an anatomical basis for clinical implant esthetics,we evaluated the morphology of the nasopalatine canal(NPC) and analyzed labial and interproximal bone anatomy at the maxillary anterior region.We sought to investigate the effect of maxillary protrusion and tooth labiolingual inclination on labial bone anatomy in Chinese adults.Three dimensional(3D) images were reconstructed using cone-beam computed tomography(CBCT) images from 80 Chinese subjects and by SimPlant 11.04.The dimensions of the NPC,the thickness and profile of the labial bone,the width and height of the interproximal bone,angle sella-nasion-subspinale(SNA) and angle upper central incisor-nasion,subspinale(U1-NA) were measured.The incisive foramen of the NPC was markedly wider than its nasal foramen.The dimension of its labial bone wall demonstrated an increasing width from the crestal to apical measurements.The labial bone at the maxillary anterior region was rather thin,especially at 3 mm below the cemento-enamel junction(CEJ) and the mid-root level;the profile of the labial bone was more curved at the central incisor,and the interproximal bone became wider and shorter posteriorly.There were significant relationships between maxillary protrusion and labial bone profile,tooth labiolingual inclination and labial bone thickness(P 〈 0.02).To achieve optimal esthetic outcome of implant,bone augmentation is necessary at the maxillary anterior region.For immediate or early placement at the maxillary anterior region,the implant should be located palatally to reduce labial bone resorption and marginal recession;its apex should be angulated palatally to avoid labial perforation at the apical region.To protect the NPC,implants at the central incisor region should be placed away from NPC. 展开更多
关键词 cone beam computed tomography(cbct nasopalatine canal(NPC) alveolar bone maxillary anterior region implant esthetics
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Comparison of bone alignment and fiducial marker alignment for online cone-beam computed tomography-guided radiation therapy for prostate cancer
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作者 Hussein M.Metwally 《Oncology and Translational Medicine》 2019年第3期131-136,共6页
Objective The aim of the study was to evaluate the coverage of the prostate when prostatic implanted fiducial markers are used to verify setup of the patients in comparison to the pelvic bones while using conebeam com... Objective The aim of the study was to evaluate the coverage of the prostate when prostatic implanted fiducial markers are used to verify setup of the patients in comparison to the pelvic bones while using conebeam computed tomography(CBCT). Methods Seventeen patients with prostate cancer were included. For each patient, daily online CBCT was done. CT planning was matched with CBCT with the help of fiducial markers(3–5 markers) and another matching with done the help of pelvic bony landmarks. Registration of clinical target volume(CTV) 1 including prostate plus seminal vesicles and CTV2 including prostate only was done and were used to confirm the target volume during the process of matching. Delineation of the rectum on every CBCT was done. Two automatic margin representing planning target volume(PTV) were created. PTV1 was generated by adding 1 cm in all directions(PTV1a) and 0.7 cm in the posterior direction(PTV1b). PTV2 was generated by adding 0.5 cm in all directions(PTV2a) and 0.3 cm in the posterior direction(PTV2b). PTV1a was prescribed to receive 46 Gy in conventional fractionation with a boost dose of 30 Gy to PTV1b. The same dose was prescribed to PTV2a and PTV2b. Calculation of the percentage of intersection between CTV1and CTV2 created on CBCT with the original CTV scan was done. A comparison between the two CTVs(CTV1and CTV2) mean dose and the original delineated CTV was done. Then a comparison to the mean dose of the original CTV of PTV1a, PTV2a(CTV1a and CTV2a), and for PTV1b and PTV2b(CTV1b and CTV2b). Calculation of the mean rectal dose and also V60, V70 and V74 was done on the delineated rectum on every CBCT, and then a comparison to the planned original rectal dose. Results The created CTV1and CTV2 intersection percentage with the original CTV1and CTV2 significantly increased by 85%(range, 65%–95%, P < 0.05), when fiducial markers were used. The main difference of the received mean dose was significantly less in comparison to pelvic bone alignment(0.03% to 2% vs 0.03% to 11.6% for PTV1a, P < 0.006;0.01% to 1.8% vs 0.03% to 10.2% for PTV2a, P < 0.014;0.08 to 2.11 vs 0.04 to 11.29 for PTV1b, P < 0.015 and 0.01 to 1.79 vs 0.01 to 9.69 for PTV2b, P < 0.004). With the use of less PTV margins, significant decrease of the rectal mean dose, V60, V70 and V74 by P < 0.004, P < 0.004, P < 0.0005 and P < 0.009, respectively. Reduction of the CTV1a and CTV1b mean dose by 1.13% and 0.28% in comparison to the initial CTV1a and CTV2a.Conclusion A significant improvement of prostatic cancer patients alignment when fiducial markers are used, with more homogenous dose distribution, and with significant decrease in PTV margins. The delivered rectal dose is significantly less allowing prostate dose escalation. 展开更多
关键词 cone-beam computed tomography(cbct) PROSTATE cancer BONE ALIGNMENT fiducial marker ALIGNMENT
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A Pilot Survey of Odontomas for Size Constancy Using Cone-Beam Computed Tomography: Effect of Age, Sex, Lesion Location, and Histological Type: A Case Series
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作者 Shinichiro Yamada Hizuru Osanai +2 位作者 Katsumitsu Shimada Hiromasa Hasegawa Keiichi Uchida 《Open Journal of Stomatology》 2021年第12期467-477,共11页
<strong>Objectives: </strong>Odontoma is the most common type of odontogenic tumors. Many studies have analyzed the statistical associations between odontoma location and patient age and sex, according to ... <strong>Objectives: </strong>Odontoma is the most common type of odontogenic tumors. Many studies have analyzed the statistical associations between odontoma location and patient age and sex, according to the histological tumor type. However, few studies have assessed odontoma morphological characteristics using cone-beam computed tomography (CBCT). We aimed to evaluate the association between odontoma location and size. <strong>Methods:</strong> We performed CBCT on patients with odontomas (19 patients;10 women, 9 men;average age, 12.6 [range, 6 - 34] years) according to the pathology type at a university hospital between April 2008 and February 2017. The locations of the lesions were noted, and their sizes were measured on CBCT images. Buccolingual, mesiodistal, and vertical diameters of the lesions were recorded on the same slice with the greatest diameters on axial, coronal, and sagittal CBCT images. <strong>Results: </strong>Altogether, 9 (47.4%) and 10 (52.6%) odontomas were located in the mandible and maxilla, respectively. There was no significant difference in the mesiodistal and vertical diameters on the CBCT image between the mandibular and maxillary groups when the odontoma size was compared with location (p < 0.05). However, the average diameters in only the buccolingual diameter were significantly greater in the maxilla. There were no significant differences between the two groups according to sex, age, or histological type. <strong>Conclusions: </strong>These data suggest that the sizes of odontomas in the maxilla are affected by bone expansion in the buccolingual direction, but they may be invariable in most settings. Three-dimensional assessment across the age groups suggests a lack of variation in size. 展开更多
关键词 cone-beam computed tomography (cbct) ODONTOMA SIZE Location
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Validation of a novel imaging approach using multi-slice CT and cone-beam CT to follow-up on condylar remodeling after bimaxillary surgery 被引量:7
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作者 laura ferreira pinheiro nicolielo jeroen van dessel +5 位作者 eman shaheen carolina letelier marina codari constantinus politis ivo lambrichts reinhilde jacobs 《International Journal of Oral Science》 SCIE CAS CSCD 2017年第3期139-144,共6页
The main goal of this study was to introduce a novel three-dimensional procedure to objectively quantify both inner and outer condylar remodelling on preoperative multi-slice computed tomography (MSCT) and postopera... The main goal of this study was to introduce a novel three-dimensional procedure to objectively quantify both inner and outer condylar remodelling on preoperative multi-slice computed tomography (MSCT) and postoperative cone-beam computed tomography (CBCT) images. Second, the reliability and accuracy of this condylar volume quantification method was assessed. The mandibles of 20 patients (11 female and 9 male) who underwent bimaxillary surgery were semi-automatically extracted from MSCT/CBCT scans and rendered in 3D. The resulting condyles were spatially matched by using an anatomical landmark-based registration procedure. A standardized sphere was created around each condyle, and the condylar bone volume within this selected region of interest was automatically calculated. To investigate the reproducibility of the method, inter- and intra-observer reliability was calculated for assessments made by two experienced radiologists twice five months apart in a set of ten randomly selected patients. To test the accuracy of the bone segmentation, the inner and outer bone structures of one dry mandible, scanned according to the clinical set-up, were compared with the gold standard, micro-CT. Thirty-eight condyles showed a significant (P〈O.05) mean bone volume decrease of 26.4%_ 11.4% (502.9 mm3+ 268.1 mm3). No significant effects of side, sex or age were found. Good to excellent (ICC〉 0.6) intra- and inter-observer reliability was observed for both MSCT and CBCT. Moreover, the bone segmentation accuracy was less than one voxel (0.4 mm) for MSCT (0.3 mm __. 0.2 mm) and CBCT (0.4 mm _ 0.3 mm), thus indicating the clinical potential of this method for objective follow-up in pathological condylar resorption. 展开更多
关键词 condylar resorption cone-beam computed tomography mandibular condyle multi-slice computed tomography three-dimensional imaging
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伴偏侧咀嚼颞下颌关节骨关节炎患者1年随访的CBCT研究
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作者 李晓星 马博文 +5 位作者 徐鑫宇 王家柱 李鸿波 胡敏 刘洪臣 姜华 《口腔颌面修复学杂志》 2025年第1期42-49,共8页
目的:通过运用锥形束CT检查分析偏侧咀嚼与颞下颌关节骨关节炎(temporomandibular joint osteoarthritis,TMJOA)进展的相关性,探讨偏侧咀嚼不良习惯对TMJ形态和空间位置的影响。方法:采用回顾性研究纳入2021年6月至2024年6月于解放军总... 目的:通过运用锥形束CT检查分析偏侧咀嚼与颞下颌关节骨关节炎(temporomandibular joint osteoarthritis,TMJOA)进展的相关性,探讨偏侧咀嚼不良习惯对TMJ形态和空间位置的影响。方法:采用回顾性研究纳入2021年6月至2024年6月于解放军总医院第一医学中心口腔科就诊的未行临床干预治疗的颞下颌关节骨关节炎患者44例(88侧关节)作为研究对象,其中男性18例,女性26例,平均年龄为33.8岁:(18~40岁)。根据是否有偏侧咀嚼习惯分为偏侧咀嚼组:TMJOA伴偏侧咀嚼患者24例;无偏侧咀嚼组:TMJOA无偏侧咀嚼患者20例。分析TMJOA患者初次就诊和复诊(一年后)时的锥形束CT影像,观察两个时期TMJ形态和空间位置的变化,对纳入患者进行临床检查包括:下颌运动检查、触诊检查、关节弹响及杂音检查等;运用锥形束CT对颅颌面大视野扫描、影像三维重建,影像矫正后选取测量层面,在髁突最大长轴轴位、矫正冠状位、矫正矢状位对TMJ进行指标定量测量。所有测量数据应用IBM SPSS Statistics 26统计学软件进行数据分析。结果:偏侧咀嚼组和无偏侧咀嚼组TMJOA患者的性别及年龄差异均无统计学意义(P>0.05)。偏侧咀嚼组习惯侧:复诊较初诊的后间隙减少、前间隙增大、髁突水平角度增加、髁突高度减少,差异均有统计学意义(P<0.05);偏侧咀嚼组非习惯侧:复诊较初诊关节前间隙增大(P<0.05)。偏侧咀嚼组习惯侧和非习惯侧对比:习惯侧髁突高度大于非习惯侧(P<0.05)、习惯侧关节后间隙小于非习惯侧(P<0.05)。无偏侧咀嚼组:复诊左、右侧关节比初诊左、右侧关节:后间隙减少、前间隙增大、髁突水平角度增加、髁突高度减少,均有改变的趋势但差异无统计学意义(P>0.05);无偏侧咀嚼组双侧对比各项数值均无统计学意义。结论:偏侧咀嚼与颞下颌关节骨关节炎患者的病情进展密切相关,未行治疗的伴偏侧咀嚼的TMJOA患者,颞下颌关节空间位置及骨性结构均发生进一步异常改变,应及时采取临床治疗,并纠正不良咀嚼习惯。 展开更多
关键词 偏侧咀嚼 颞下颌关节骨关节炎 颞下颌关节 锥形束计算机体层摄影术
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The Importance of Three-Dimensional Imaging from CBCT in Elucidating a Well-Defined Radiolucency Image within the Maxillary Sinus: A Case Report
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作者 Ricardo Alves de Mesquita Cláudia Borges Brasileiro Tania Mara Pimenta Amaral 《Open Journal of Radiology》 2014年第3期255-259,共5页
This study describes a case of antral septum with alveolar process extension that is identified using cone-beam computed tomography (CBCT). Periapical radiolucency was observed in the maxillary sinus, and clinical and... This study describes a case of antral septum with alveolar process extension that is identified using cone-beam computed tomography (CBCT). Periapical radiolucency was observed in the maxillary sinus, and clinical and radiographic examinations ruled out the possibility of odontogenic lesions. CBCT was performed to elucidate the radiolucency identified using periapical radiography. A 3-D image indicated that the maxillary sinus extended into the alveolar process toward the palatal cortical bone in the region of the maxillary right first molar, as well as an antral septum extending from the inferior and lateral wall of the right maxillary sinus. CBCT is an important tool for use in dental practice because CBCT images reveal the entire volume of the maxillary sinus and allow for identification of patient anatomy and anatomical variations, which is essential for planning appropriate surgical interventions. 展开更多
关键词 Diagnostic imaging cone-beam computed tomography RADIOGRAPHY MAXILLARY SINUS
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不同成像参数下CBCT的成像质量分析 被引量:1
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作者 钱军 马芮 +4 位作者 谢晓艳 姜丹 邓少纯 段瑶 毋育伟 《实用口腔医学杂志》 CAS CSCD 北大核心 2024年第2期222-226,共5页
目的:主观评价和客观评估不同成像参数下CBCT的图像质量,分析图像质量的主观评价和客观评价间的关系。方法:分别采用6台不同品牌CBCT扫描仪〔3D Accuitomo(Morita)、i-CAT(Kavo)、5G(NewTom)、Smart3D(北京朗视)、DCT Pro(Vatech)、VGi(... 目的:主观评价和客观评估不同成像参数下CBCT的图像质量,分析图像质量的主观评价和客观评价间的关系。方法:分别采用6台不同品牌CBCT扫描仪〔3D Accuitomo(Morita)、i-CAT(Kavo)、5G(NewTom)、Smart3D(北京朗视)、DCT Pro(Vatech)、VGi(NewTom)〕,在各个品牌的典型曝光条件下(电压和电流强度不同)扫描空间分辨率模体和高仿真头模,7位医师对拍摄的CBCT图像进行主观评价打分,比较不同CBCT扫描仪的空间分辨率和对常见口腔解剖结构的可见性。客观评价指标采用各仪器所获的图像空间分辩率(LP/mm)。结果:7位医师的组内一致性和组间一致性均无显著性差异。主观评价New Tom 5G为2分,i-CAT为5分,其余4个品牌匀为4分,客观评价i-CAT的LP/mm为1.8,Smart3D为2.0,其余4个品牌为1.0~1.7。在相同管电流条件下,不同管电压的图像主观质量有显著性差异。在相同管电压条件下,不同管电流的图像主观质量有显著性差异。结论:图像质量的主客观评价具有一定的一致性,不同品牌之间的客观评价差异可能与电压、电流强度不同有关。 展开更多
关键词 锥形束计算机断层扫描 图像质量 主观评价 客观评价
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Scatter correction method for cone-beam CT based on interlacing-slit scan 被引量:3
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作者 黄魁东 张华 +2 位作者 史仪凯 张亮 徐哲 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第9期515-521,共7页
Cone-beam computed tornography (CBCT) has the notable features of high efficiency and high precision, and is widely used in areas such as medical imaging and industrial non-destructive testing. However, the presence... Cone-beam computed tornography (CBCT) has the notable features of high efficiency and high precision, and is widely used in areas such as medical imaging and industrial non-destructive testing. However, the presence of the ray scatter reduces the quality of CT images. By referencing the slit collimation approach, a scatter correction method for CBCT based on the interlacing-slit scan is proposed. Firstly, according to the characteristics of CBCT imaging, a scatter suppression plate with interlacing slits is designed and fabricated. Then the imaging of the scatter suppression plate is analyzed, and a scatter correction Calculation method for CBCT based on the image fusion is proposed, which can splice out a complete set of scatter suppression projection images according to the interlacing-slit projection images of the left and the right imaging regions in the scatter suppression plate, and simultaneously complete the scatter correction within the fiat panel detector (FPD). Finally, the overall process of scatter suppression and correction is provided. The experimental results show that this method can significantly improve the clarity of the slice images and achieve a good scatter correction. 展开更多
关键词 cone-beam computed tomography scatter correction interlacing slits image fusion
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基于CBCT观察上颌阻生尖牙患者蝶鞍形态变异情况
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作者 缪世维 严沁月 +3 位作者 胡丹艳 曹丹 Izadikhah Iman 严斌 《口腔医学》 CAS 2024年第2期105-109,共5页
目的 利用锥形束CT(cone-beam computed tomography,CBCT)探讨上颌尖牙阻生与蝶鞍形态变异的相关性,从三维方向上评价蝶鞍变异对上颌尖牙阻生的临床预判。方法 收集125例上颌阻生尖牙患者(研究组)和125例与之相匹配的尖牙正常萌出者(对... 目的 利用锥形束CT(cone-beam computed tomography,CBCT)探讨上颌尖牙阻生与蝶鞍形态变异的相关性,从三维方向上评价蝶鞍变异对上颌尖牙阻生的临床预判。方法 收集125例上颌阻生尖牙患者(研究组)和125例与之相匹配的尖牙正常萌出者(对照组)。将所有样本CBCT数据导入Dolphin软件,进行重建头颅侧位片和三维图像,记录观察各组蝶鞍桥接(Ⅰ、Ⅱ、Ⅲ型)的类型分布和发生情况。使用SPSS 25.0软件对各组结果进行统计学分析。结果 研究组蝶鞍桥接的发生率显著高于对照组(P=0.004),PIC(腭侧尖牙阻生)组蝶鞍桥接的发生率显著高于对照组(P=0.007),Ⅱ型和Ⅲ型蝶鞍桥接分布和对照组存在统计学差异(P=0.012)。而BIC(唇侧尖牙阻生)组和对照组蝶鞍桥接的发生情况无统计学差异。三维重建图像上各组间蝶鞍桥接发生率无统计学差异(P>0.05)。结论 上颌尖牙阻生与蝶鞍桥接的发生情况有相关性,但仅上颌尖牙腭侧阻生患者更易发生蝶鞍桥接,而上颌尖牙唇侧阻生患者蝶鞍桥接的发生情况无变化。 展开更多
关键词 锥形束CT 上颌阻生尖牙 蝶鞍桥接
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基于CBCT中牙髓和牙体体积的机器学习用于青少年儿童年龄推断
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作者 韩佳璇 沈诗慧 +3 位作者 吴怡文 孙晓丹 陈天南 陶疆 《法医学杂志》 CAS CSCD 北大核心 2024年第2期143-148,共6页
目的利用锥形束计算机体层成像(cone beam computed tomography,CBCT)影像中左上颌中切牙与左上颌尖牙的牙髓体积和牙体体积,采用逐步回归法和机器学习方法分别推断青少年儿童年龄,并对推断效果进行比较分析。方法收集498例上海市汉族... 目的利用锥形束计算机体层成像(cone beam computed tomography,CBCT)影像中左上颌中切牙与左上颌尖牙的牙髓体积和牙体体积,采用逐步回归法和机器学习方法分别推断青少年儿童年龄,并对推断效果进行比较分析。方法收集498例上海市汉族青少年儿童口腔颌面CBCT影像,测量左上颌中切牙与尖牙的牙髓体积和牙体体积并加以运算,运用K-最近邻、岭回归和决策树3种机器学习算法以及逐步回归法建立4个年龄推断模型,计算并比较决定系数、平均误差、均方根误差、均方误差和平均绝对误差等指标。绘制相关性热图,对参数间的单调关系进行可视化分析。结果K-最近邻模型(R^(2)=0.779)和岭回归模型(R^(2)=0.729)相对于逐步回归法(R^(2)=0.617)表现更为优越,而决策树模型(R^(2)=0.494)的拟合效果较差。相关性热图显示,年龄和牙髓体积、牙髓与牙体硬组织的体积比以及牙髓与牙体的体积比之间呈单调负相关。结论牙髓体积及牙髓体积占比与年龄之间存在密切关系,采用基于CBCT的机器学习方法能够提供更为准确的年龄推断结果,为进一步开展基于CBCT的深度学习牙龄推断研究奠定基础。 展开更多
关键词 法医人类学 法医齿科学 年龄推断 锥形束计算机体层成像 机器学习 青少年 儿童
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Inter-Occlusal Separation in CBCT Imaging: Rationale and Method
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作者 Amr El-Beialy Yehya Mostafa 《Open Journal of Medical Imaging》 2012年第2期76-79,共4页
A major advantage of CBCT is the ability to allow single-step data acquisition that computes all our diagnostic information and substitutes several conventional procedures of record taking. Yet, there are several prot... A major advantage of CBCT is the ability to allow single-step data acquisition that computes all our diagnostic information and substitutes several conventional procedures of record taking. Yet, there are several protocols for CBCT imaging as regards the interocclusal separation, each with a drastic shortcoming. The authors herein propose a protocol that offers acceptable inter-occlusal separation during CBCT imaging using a radiolucent splint that guarantees reproducibility, undisrupted facial form, centric condylar position concurrently with feasibility for occlusal analysis, separation of the maxillary and mandibular teeth and hence digital simulation of the orthodontic treatment. 展开更多
关键词 Diagnosis Diagnostic imaging RADIOGRAPHY cone-beam computed tomography
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基于迭代配准和感知损失的肺部伪CT合成深度学习算法
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作者 杨涛 黄淼 +3 位作者 刘琮 胡志华 陶莉莉 张淑平 《中国医学物理学杂志》 2025年第1期59-66,共8页
目的:使用深度学习算法通过学习肺部CT域图像特征,将锥形束CT(CBCT)合成高质量伪CT(sCT)图像。方法:本研究提出一种基于感知损失的循环生成式对抗网络模型(CycleGAN)和迭代配准的sCT生成算法,首先,结合感知损失和循环一致性损失来训练Cy... 目的:使用深度学习算法通过学习肺部CT域图像特征,将锥形束CT(CBCT)合成高质量伪CT(sCT)图像。方法:本研究提出一种基于感知损失的循环生成式对抗网络模型(CycleGAN)和迭代配准的sCT生成算法,首先,结合感知损失和循环一致性损失来训练CycleGAN模型生成高质量的sCT图像,然后,利用Elastix配准工具对所生成的sCT图像和计划CT(pCT)图像进行配准,并用来迭代CycleGAN生成器模型。结果:在获取到的70例肺部肿瘤患者的pCT与CBCT数据上进行实验,从定量指标上看,利用本算法生成的sCT与pCT对比的结构相似度指标比CBCT与pCT对比的提升了11.9%,由0.825上升到0.923,均方绝对误差由110.97 HU降至78.62 HU,峰值信噪比由32.21 dB上升到34.74 dB,互信息由1.187上升到1.418。可视化评估中可见该算法大幅度消除了CBCT切片的散射伪影,突显骨质结构同时也修复了软组织结构。通过与当下流行的U-CycleGAN,R-CycleGAN和CUT模型对比,说明了本算法的有效性。结论:本文算法生成sCT图像能够有效减小CBCT与pCT间的剂量误差与结构误差,使其应用于精准的剂量计算,辅助医生的临床放疗诊断成为可能。 展开更多
关键词 锥形束CT CycleGAN 感知损失 Elastix 图像合成
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成人骨性Ⅲ类错牙合伴下颌偏斜患者下颌骨三维对称性的CBCT观察分析 被引量:12
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作者 刘可 王珊 +4 位作者 王林 于剑南 赵宏 刘敏 赵春洋 《实用口腔医学杂志》 CAS CSCD 北大核心 2014年第3期352-356,共5页
目的:研究成人骨性Ⅲ类错伴下颌偏斜患者下颌骨的三维特征。方法:纳入正畸成人骨性Ⅲ类错患者62名,按照颏点的偏离程度分为颜面部不对称组30例和颜面部对称组32例,用锥形束CT(cone-beam computed tomography,CBCT)三维扫描获得颅面... 目的:研究成人骨性Ⅲ类错伴下颌偏斜患者下颌骨的三维特征。方法:纳入正畸成人骨性Ⅲ类错患者62名,按照颏点的偏离程度分为颜面部不对称组30例和颜面部对称组32例,用锥形束CT(cone-beam computed tomography,CBCT)三维扫描获得颅面部DICOM数据,采用Dolphin 11.0对下颌骨进行三维重建,选择描述下颌骨骨性结构特征的13个点进行描记,对下颌骨37个变量进行分析统计。结果:颜面部不对称组偏斜侧髁突及下颌角点相对于偏斜对侧处于向后、向外、向上的位置,偏斜对侧有着更长的下颌体、下颌支、髁突和更大的下颌支倾斜度及髁突倾斜度。结论:髁突、下颌支、下颌体的不对称生长发育及下颌骨的旋转都是导致下颌偏斜的因素。 展开更多
关键词 下颌偏斜 骨性Ⅲ类错(牙合) 下颌骨 锥形束CT(cbct) 测量
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54例正常人双侧颞下颌关节CBCT测量值分析 被引量:34
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作者 曹均凯 王照五 +2 位作者 刘洪臣 胡敏 姜华 《口腔颌面修复学杂志》 2008年第4期291-294,共4页
目的:探讨应用CBCT(cone-beam computed tomography)对成年人两侧颞下颌关节进行多项指标数据测量分析。方法:在TMJ成像与测量技术的基础上,筛选出正常成人54例,通过严格的TMJ临床检查确定为健康关节,利用Newtom 9000 CBCT对其ICP位颞... 目的:探讨应用CBCT(cone-beam computed tomography)对成年人两侧颞下颌关节进行多项指标数据测量分析。方法:在TMJ成像与测量技术的基础上,筛选出正常成人54例,通过严格的TMJ临床检查确定为健康关节,利用Newtom 9000 CBCT对其ICP位颞下颌关节进行成像后测量分析。结果:在轴位测得髁状突水平角以及单侧髁状突距矢状中线的距离;平行于髁状突长轴的斜位,测髁状突长轴径,垂直角度,沿髁状突长轴顶内外极间任意角间隙宽度;垂直于髁状突长轴的斜位测量关节髁状突前中后任意角间隙宽度,关节凹深度和前斜面角度关节颈厚度;矢状位测关节髁状突前中后任意角间隙宽度,关节凹深度和前斜面角度关节颈厚度。结论:正常成人双侧髁状突位置及关节窝形态性别差异不明显,双髁状突位置及关节窝形态基本对称。 展开更多
关键词 颞下颌关节 CT cbct测量值
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CBCT与螺旋CT对颞颌关节成像的比较 被引量:19
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作者 曹均凯 王照五 +4 位作者 石校伟 师占平 姜华 胡敏 刘洪臣 《口腔颌面修复学杂志》 2009年第4期217-219,共3页
目的:通过锥体束CT(CBCT)与螺旋CT对颞颌关节成像的比较,探讨CBCT影像与螺旋CT对颞下颌关节成像大体解剖结构的一致性;通过比较分析研究CBCT在颞下颌关节检查成像中的临床诊断意义。方法:对1名成人通过严格的TMJ临床检查为健康关节志愿... 目的:通过锥体束CT(CBCT)与螺旋CT对颞颌关节成像的比较,探讨CBCT影像与螺旋CT对颞下颌关节成像大体解剖结构的一致性;通过比较分析研究CBCT在颞下颌关节检查成像中的临床诊断意义。方法:对1名成人通过严格的TMJ临床检查为健康关节志愿者在同一时间行CBCT与螺旋CT扫描,并进行分析。结果:CBCT与螺旋CT二者重建的解剖形态影像基本一致。受检者的影像均可较清晰再现颞下颌关节结构形态及相对位置关系。结论:比较证实CBCT能准确反映颞下颌关节解剖形态,具有广泛的临床应用前景。 展开更多
关键词 颞下颌关节 cbct 螺旋CT
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CBCT在诊治埋伏阻生牙中的应用 被引量:11
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作者 王磊 阮征 +3 位作者 张劲娥 袁晓晔 何艳萍 李耀俊 《口腔颌面外科杂志》 CAS 2014年第4期308-310,共3页
目的:探讨CBCT在埋伏阻生牙诊治中的应用。方法:对56例(37颗多生牙、41颗阻生牙)经全景片检查需进一步明确诊断的埋伏阻生牙,进行CBCT扫描,通过三维重建、矢状位、冠状位及轴位断层进行分析。结果:与全景片比较,CBCT能准确定位埋伏阻生... 目的:探讨CBCT在埋伏阻生牙诊治中的应用。方法:对56例(37颗多生牙、41颗阻生牙)经全景片检查需进一步明确诊断的埋伏阻生牙,进行CBCT扫描,通过三维重建、矢状位、冠状位及轴位断层进行分析。结果:与全景片比较,CBCT能准确定位埋伏阻生牙的位置、生长方向、数量,准确率差异有统计学意义(P<0.05)。结论:CBCT可以更直观、准确地对埋伏阻生牙定位,特别是在上颌前牙区的临床诊治更有应用价值。 展开更多
关键词 埋伏牙 阻生牙 cbct
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CBCT在牙齿纵裂中的临床诊断价值评价 被引量:11
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作者 杜毅 唐开亮 +1 位作者 于西佼 路吉坤 《牙体牙髓牙周病学杂志》 CAS 北大核心 2010年第8期450-453,共4页
目的:比较CBCT与X线根尖片在诊断牙齿纵裂准确度中的差异性,评价CBCT在牙齿纵裂中的临床诊断价值。方法:在病人知情同意下选取临床上怀疑有牙根纵裂的病人40例(40个牙),均拍摄X线根尖片并进行CBCT扫描。分别由2位专家采用单盲法对CBCT... 目的:比较CBCT与X线根尖片在诊断牙齿纵裂准确度中的差异性,评价CBCT在牙齿纵裂中的临床诊断价值。方法:在病人知情同意下选取临床上怀疑有牙根纵裂的病人40例(40个牙),均拍摄X线根尖片并进行CBCT扫描。分别由2位专家采用单盲法对CBCT、根尖片影像进行诊断,比较两种影像学方法诊断牙齿纵裂中的真实性。结果:CBCT扫描诊断牙齿纵裂的敏感性Sen、粗符合率CA、约登指数γ、阴性预测值PV-分别为97.37%、97.50%、97.37%、66.67%,而X线根尖片则为73.68%、72.50%、23.68%、9.09%,在诊断牙齿纵裂方面,CBCT扫描与X线根尖片相比有更高的敏感性和准确度,差别具有统计学意义(P<0.05)。结论:与X线根尖片相比CBCT扫描对牙齿纵裂的诊断具有更高的准确度,有重要的临床应用价值。 展开更多
关键词 锥束CT X线根尖片 牙齿纵裂
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上颌四眼圈簧扩弓后对上颌牙齿及上颌骨变化影响的CBCT研究 被引量:10
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作者 张月兰 韦大鹏 +3 位作者 Blessing Sayi 杨亚欣 杨亚普 王晨曦 《实用口腔医学杂志》 CAS CSCD 北大核心 2016年第2期216-219,共4页
目的:使用锥体束CT(CBCT)评估上颌四眼簧慢速扩弓后上颌牙齿及上颌骨宽度的变化。方法:选择13例需要综合性正畸治疗的患者(男5例,女8例),平均年龄(14.4±2.2)岁,使用上颌四眼圈簧扩弓。对患者扩弓前(T1)后(T2)的变化进行CBCT扫描,... 目的:使用锥体束CT(CBCT)评估上颌四眼簧慢速扩弓后上颌牙齿及上颌骨宽度的变化。方法:选择13例需要综合性正畸治疗的患者(男5例,女8例),平均年龄(14.4±2.2)岁,使用上颌四眼圈簧扩弓。对患者扩弓前(T1)后(T2)的变化进行CBCT扫描,测量扩弓前后两侧尖牙、第一前磨牙、第二前磨牙和第一磨牙之间的牙冠和根尖之间的宽度,第一磨牙的倾斜度,基骨弓和腭中缝宽度的变化。应用SPSS 17.0软件对测量结果进行配对t检验。结果:四眼圈簧扩弓后牙弓变化明显。4对牙的牙间距分别增加了(2.47±1.05)mm、(2.97±1.90)mm、(2.79±1.21)mm、(3.15±1.15)mm,根尖距分别减小了(1.19±0.40)mm、(2.12±0.68)mm、(2.02±0.65)mm、(1.34±0.63)mm,左侧磨牙倾斜度减小了4.45°±2.86°,右侧磨牙倾斜度减小了4.02°±1.45°,基骨弓宽度增加了(2.37±0.96)mm,腭中缝宽度增加了(1.21±0.50)mm,差异均具有统计学意义(P<0.001)。结论:四眼圈簧扩弓器对上颌牙弓的扩弓主要通过牙齿倾斜移动完成,而非整体移动。 展开更多
关键词 四眼圈簧 锥体束CT(cbct) 上颌扩弓
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