• Imaging Science in Dentistry
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• 제38권3호
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• pp.153-161
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• 2008

Purpose : To compare and evaluate the diagnostic ability of cone beam computed tomography (CBCT) and magnetic resonance imaging (MRI) of the temporomandibular joint (TMJ). Materials and Methods : CBCT and MRI of 46 TMJs of 23 patients with TMJ disorders were evaluated. They were divided into 3 groups according to the position of the articular disc of the TMJ at closed mouth position and the reduction of the disc during open mouth position on MRI: no disc displacement group (NDD), disc displacement with reduction group (DDR), and disc displacement without reduction group (DDWR). With PACS viewing soft-wares, position of mandibular condyle in the articular fossa, osseous change of mandibular condyle, shape of articular fossa, and mediolateral and anteroposterior dimensions of mandibular condyle were evaluated on CBCT and MRI. Each value was tested statistically. Results : The position of mandibular condyle in the articular fossa were concentric in the NDD, DDR, and DDWR of CBCT and NDD of MRI. However, condyle was positioned posteriorly in DDR and DDWR of MRI. Flattening, sclerosis and osteophyte of the mandibular condyle were much more apparent on DDR of CBCT than MRI. And the erosion of the condyle was much more apparent on DDWR of MRI than CBCT. Box and Sigmoid types of articular fossa were found most frequently in DDR of MRI. Flattened type was found most frequently in DDR of CBCT and deformed type was found most frequently in DDWR of CBCT. No significant difference in mediolateral and anteroposterior dimensions were shown on CBCT and MRI. Conclusion : Since MRI and CBCT has unique diagnostic imaging ability, both modalities should be used together to supplement each other to evaluate TMJ.

• Imaging Science in Dentistry
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• 제37권2호
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• pp.93-102
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• 2007

Purpose: Cone beam computed tomography (CBCT) provides a lower dose and cost alternative to conventional CT, promising to revolutionize the practice of oral and maxillofacial radiology. The purpose of this study was to evaluate the absorbed and effective doses of Implagraphy and VCT (Vatech Co., Hwasung, Korea) and compare them with those of panoramic radiography. Materials and Methods: Thermoluminescent dosimeter (TLD) chips were placed at 27 sites throughout the layers of Female ART Head and Neck Phantom for dosimetry. Implagraphy, VCT units, and Planmeca Proline XC panoramic unit were used for radiation exposures. Radiation weighted doses and effective doses were measured and calculated using 1990 and 2005 ICRP tissue weighting factors. Results: Effective doses in Sv (ICRP 2005, ICRP 1990) were 90.19, 61.62 for Implagraphy at maxillay molar area, 123.20, 90.02 for Implagraphy at mandibular molar area, 183.55, 139.26 for VCT and 40.92, 27.16 for panoramic radiography. Conclusion: Effective doses for VCT and Implagraphy were only about 2.2 to 4.5 times greater than those for panoramic radiography. VCT and Implagraphy, CBCT machines recently developed in Korea, showed moderately low effective doses.

• Imaging Science in Dentistry
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• 제51권1호
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• pp.87-90
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• 2021

The increased use of cone-beam computed tomographic (CBCT) scans has made it increasingly necessary to evaluate incidental findings on CBCT scans. This report describes the case of a 66-year-old female patient who presented to the Department of Oral and Maxillofacial Pathology, Radiology and Medicine at the College of Dentistry of the author's institution and underwent a CBCT scan for maxillary alveolar process implant planning. Upon evaluation of the CBCT scan, a radiopaque (soft tissue attenuation) mass in the left superior aspect of the nasal cavity and left locule of the sphenoid sinus with opacification of the left locule of the sphenoid sinus was incidentally noted. These radiographic findings were suggestive of a space-occupying mass with a high possibility of malignancy. A further medical evaluation confirmed renal cell cancer metastasis to the sphenoid sinus. This study shows the significance of reviewing the entire CBCT scan for incidental findings.

• Imaging Science in Dentistry
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• 제47권4호
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• pp.275-279
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• 2017

Soft tissue calcification is a pathological condition in which calcium and phosphate salts are deposited in the soft tissue organic matrix. This study presents an unusual calcification noted in the cartilaginous portion of the Eustachian tube. A 67-year-old woman presented for dental treatment, specifically for implant placement, and cone-beam computed tomography (CBCT) was performed. The CBCT scan was reviewed by a board-certified oral and maxillofacial radiologist and revealed incidental findings of 2 distinct calcifications in the cartilaginous portion of the Eustachian tube. To the authors' knowledge, no previous study has reported the diagnosis of Eustachian tube calcification using CBCT. This report describes an uncommon variant of Eustachian tube calcification, which has a significant didactic value because such cases are seldom illustrated either in textbooks or in the literature. This case once again underscores the importance of having CBCT scans evaluated by a board-certified oral and maxillofacial radiologist.

• Imaging Science in Dentistry
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• 제50권3호
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• pp.183-192
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• 2020

Purpose: This study was performed to assess the accuracy of preoperative cone-beam computed tomography (CBCT), when justified for other reasons, in locating the apical foramen and establishing the working length. Materials and Methods: Six electronic databases were searched for studies on this subject. All studies, of any type, were included if they compared measurements of working length with preoperative CBCT to measurements using an electronic apex locator (EAL) or histological reference standard. Due to the high levels of heterogeneity, an inverse-variance random-effects model was chosen, and weighted mean differences were obtained with 95% confidence intervals and P values. Results: Nine studies were included. Compared to a histological reference standard, CBCT indicated that the apical foramen was on average 0.40 mm coronal of its histological position, with a mean absolute difference of 0.48 mm. Comparisons were also performed to an EAL reference standard, but the conclusions could not be considered robust due to high levels of heterogeneity in the results. Conclusion: A low level of evidence is produced suggesting that preoperative CBCT shows the apical foramen to be on average 0.40 mm coronal to its histological position, with a mean absolute difference of 0.48 mm.

• Restorative Dentistry and Endodontics
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• 제40권2호
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• pp.161-165
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• 2015

Three-dimensional (3D) reconstruction of cone-beam computed tomography (CBCT) scans appears to be a valuable method for assessing pulp canal configuration. The aim of this report is to describe endodontic treatment of a mandibular second premolar with aberrant pulp canal morphology detected by CBCT and confirmed by 3D modeling. An accessory canal was suspected during endodontic treatment of the mandibular left second premolar in a 21 year old woman with a chief complaint of pulsating pain. Axial cross-sectional CBCT scans revealed that the pulp canal divided into mesiobuccal, lingual, and buccal canals in the middle third and ended as four separate foramina. 3D modeling confirmed the anomalous configuration of the fused root with a deep lingual groove. Endodontic treatment of the tooth was completed in two appointments. The root canals were obturated using lateral compaction of gutta-percha and root canal sealer. The tooth remained asymptomatic and did not develop periapical pathology until 12 months postoperatively. CBCT and 3D modeling enable preoperative evaluation of aberrant root canal systems and facilitate endodontic treatment.

• Imaging Science in Dentistry
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• 제49권3호
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• pp.209-212
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• 2019

Purpose: Fossa navicularis is a bone defect in the clivus. Familiarity with this anatomical variant is important because it is close to vital anatomical structures in the base of the skull. The aim of this study was to determine the prevalence and morphometric properties of fossa navicularis within the clivus in a Turkish subpopulation using cone-beam computed tomography (CBCT). Materials and Methods: A total of 168 CBCT scans (female: 96, male: 71) were evaluated. High-quality CBCT images of patients without a syndromic condition or a history of neurological disease or surgery were included in the study. The prevalence, depth, length, and width of the fossa navicularis were performed. Results: The prevalence of fossa navicularis was 27.5% (n=46 patients). Sex was not associated with the depth, length, or width of the fossa navicularis (P>0.05). A significant positive correlation was found between age and length of the fossa navicularis(P>0.05). Conclusion: Fossa navicularis was found to be rare (27.5%). Anatomical variants of the skull base can also be clearly identified on CBCT images. The results of this study may be useful to radiologists, anatomists, and surgeons interested in the skull base.

• Restorative Dentistry and Endodontics
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• 제49권1호
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• pp.1.1-1.18
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• 2024

The implementation of imaging methods that enable sensitive and specific observation of anatomical structures has been a constant in the evolution of endodontic therapy. Cone-beam computed tomography (CBCT) enables 3-dimensional (3D) spatial anatomical navigation in the 3 volumetric planes (sagittal, coronal and axial) which translates into great accuracy for the identification of endodontic pathologies/conditions. CBCT interpretation consists of 2 main components: (i) the generation of specific tasks of the image and (ii) the subsequent interpretation report. A systematic and reproducible method to review CBCT scans can improve the accuracy of the interpretation process, translating into greater precision in terms of diagnosis and planning of endodontic clinical procedures. MEDLINE (PubMed), Web of Science, Google Scholar, Embase and Scopus were searched from inception to March 2023. This narrative review addresses the theoretical concepts, elements of interpretation and applications of the CBCT scan in endodontics. In addition, the contents and rationale for reporting 3D endodontic imaging are discussed.

• Imaging Science in Dentistry
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• 제40권2호
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• pp.93-97
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• 2010

This report was to show the radiographic appearances of the fungus ball in a paranasal sinus and to emphasize the scan area of cone beam computed tomography (CBCT) to detect the calcification in the paranasal sinus. A seventyfour-year-old woman visited our department for the implant rehabilitation at both maxillary posterior edentulous region. Pre-operative radiographic examinations including the panoramic, CBCT, and multidector CT images were taken. An opacification in the right maxillary sinus was observed on the multiplanar image of CBCT, however the pre-determined scan area of CBCT in this report hardly showed the calcifications at the central portion of the maxillary sinus. The opacification in the maxillary sinus could be misdiagnosed as chronic maxillary sinusitis if the calcification of fungus ball was not simultaneously detected. The scan area of pre-operative CBCT needs to be enough to scan the paranasal sinus from top to bottom.

• 한국의학물리학회지:의학물리
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• 제17권4호
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• pp.207-211
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• 2006

kV cone-beam CT (CBCT)가 결합된 선형가속기의 등장으로 더욱 정확한 영상유도 방사선치료(Image-guided radiation therapy, IGRT)가 가능해졌다. IGRT는 영상장비를 이용해 표적의 이동을 보정할 수 있는 방사선치료기술로, CBCT를 이용한 IGRT의 경우 내부 장기의 정보를 바탕으로 병변의 이동을 정확히 알 수 있다. 내부 장기의 정보를 얻기 위해서는 방사선이 조사되기 바로 전에 환자의 CBCT 영상을 획득하여 치료계획 시 사용한 모의치료 CT영상과 정합을 수행하게 된다. 본 연구에서는 CBCT 영상의 재구성 품질에 따른 정합결과를 비교해 보았다. 6명의 환자로부터 총 56개의 CBCT 투과 정보를 획득하여 분석한 결과, 평행이동벡터의 차가 1 mm를 초과하는 경우는 단 3개에 불과하였다. 회전이동의 경우, x, y, z, 세 축을 모두 고려하였으며, 그 결과 총 168 ($56{\times}3$)개에서 단 3개만이 $1^{\circ}$ 이상의 차이를 나타냈다.