• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권6호
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• pp.492-498
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• 2009

We sought to evaluate the relationship between the mandibular canal and impacted mandibular third molars by using dental cone beam computed tomograph(CBCT) for third molar surgery. A total of 111 patients(177 teeth) offered the images through CBCT and panoramic radiography for the extraction of the mandibular third molars. In CBCT, the accurate relationship between the third molar and the mandibular canal were evaluated. In panoramic radiographies, we evaluated the impacted level and superimposition sign of the mandibular third molar with the mandibular canal, and also, the radiopacity of the white line in the canal. Data were statistically analyzed and estimated by $X^2$-test. In CBCT finding, high prevalence of contact between the mandibular canal and roots occured in the deep impacted third molars, narrowing mandibular canals, bending mandibular canals and cases where the radiopacity of white line of canals were "absence" on panoramic images. It showed statistical significance (P<0.05). When evaluating the mandibular canal and the roots through the panoramic radiography for third molar extraction, it could be difficult to diagnosis accurately. Thus, it is required to have an accurate diagnostic approach through CBCT that could evaluated the location between mandibular canal and root.

• Imaging Science in Dentistry
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• 제38권2호
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• pp.95-101
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• 2008

Purpose: To assess the positional relationship between the maxillary sinus floor and the apex of the maxillary first molar using cone beam computed tomograph (CBCT). Materials and Methods: CBCTs from 127 subjects were analysed. A total of 134 maxillary first molars were classified according to their vertical and horizontal positional relationship to the maxillary sinus floor and measured according to the distance between the maxillary sinus floor and the maxillary first molar. Results: Type III (The root projected laterally on the sinus cavity but its apex is outside the sinus boundaries) was dominated between 10 and 19 years and type I (The root apex was not in contact with the cortical borders of the sinus) was dominated (P<0.05) between 20 and 72 years on the vertical relationship between the maxillary sinus floor and the apex of the maxillary first molar. The maxillary sinus floor was located more at the apex (78.2%) than at the furcation (21.3%) for the palatal root. The distance from the root apex to the maxillary sinus floor confined to type I was increased according to the ages (P<0.05). Type M (The maxillary sinus floor was located between the buccal and the palatal root) was most common (72.4%) on the horizontal relationship between the maxillary sinus floor and the apex of the maxillary first molar. Conclusion: CBCT can provide highly qualified images for the maxillary sinus floor and the root apex of the maxillary first molar.

• Imaging Science in Dentistry
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• 제39권1호
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• pp.41-49
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• 2009

Purpose: To detect the progression of experimentally induced periapical lesions on periapical radiograph and cone beam computed tomograph (CBCT) by quantitative analysis. Materials and Methods: After the removal of coronal pulps from premolars of two Beagle dogs, the root canals of premolars were exposed to oral environment during one week and then sealed for 70 days. Digital periapical radiographs and CBCTs were taken at baseline and every 7 days for 77 days after pulp exposure. We examined occurrence and areas of periapical bone resorption. Three comparative groups of CBCT radiographs were prepared by average projection of thin slabs with different bucco-lingual thicknesses (0.1, 3.0, and 8.0 mm) using a 3D visualization software. Radiographic densities were compensated by image normalization. Digital images were processed with mathematical morphology operations. The radiographic density and morphological features of periapical lesions were compared among three groups of CBCT in different time points. Results: In the CBCT group with 0.1 mm thickness, radiographic density (p<0.05) and trabecular bone area (p<0.01) were significantly decreased at the fifth week. However, in the CBCT groups with 3 mm and 8 mm thickness and periapical radiographs, none of densitometric and morphological features showed any significant differences in different time points. Radiographic density of periapical lesion showed increasing tendency at the eleventh week after pulp exposure. Conclusion: Radiographic detection of periapical lesions was possible at the fifth week after pulp contamination by quantitative method and was affected by buccolingual bone thickness.

• Imaging Science in Dentistry
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• 제39권2호
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• pp.81-87
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• 2009

Purpose: To evaluate the anteroposterior length and buccal angle of the anterior loop, and the size and location of the mental foramen using cone beam computed tomography (CBCT). Materials and Methods: 100 CBCT images from 87 adults (43 males and 44 females) ranging in age from 20 to 73 years (average 50 years) with edentulous ridge of the mandibular premolar region were obtained. Axial, sagittal, coronal images were reconstructed from Dental and Block Images of CBCT. The anteroposterior length, shape and buccal angle of the anterior loop, and the size and location of the mental foramen were calculated from reconstructed images of axial, sagittal and coronal CBCT. Results: The anteroposterior length and buccal angle of the mental canal was 4.0${\pm}$1.2mm, 37.8${\pm}$11.60$^{\circ}$respectively. The loop type with straight course was the most common shape of the mental canal. The location of the mental foramen below the apex of the lower second premolar (78%) was the most common. The maximum size of the mental foramen was 4.6${\pm}$1.0 mm in width and 3.0${\pm}$0.6 mm in height. The inner size of the mental canal was 2.6${\pm}$0.6 mm in width and 2.1 mm${\pm}$0.4 mm in height. Conclusion: CBCT is useful to evaluate the anterior loop and mental foramen of the mandibular canal. Safe guideline of 4 mm from the most anterior point of the mental foramen is recommended for implant and surgical treatment. (Korean J Oral Maxillofac Radiol 2009; 39: 81-7)

• Imaging Science in Dentistry
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• 제52권4호
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• pp.333-342
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• 2022

Purpose: The goal of this systematic review was to compare the use of cone-beam computed tomography (CBCT) with that of computed tomography (CT) for volumetric evaluations of the tongue and oral cavity. Materials and Methods: A search for articles was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-analyses guidelines. The PubMed, Scopus, ScienceDirect, and SAGE Journals databases were searched for articles published between 2011 and 2021. Articles were screened and assessed for eligibility. Screening involved checking for duplication, reading the title and abstract, and reading the full text. Results: The initial search retrieved 25,780 articles. Application of the eligibility criteria yielded 16 articles for qualitative analysis. Multiple uses of CBCT were identified. In several studies, researchers assessed the volumetric correlation between tongue and oral cavity volumes, as well as other parameters. Post-treatment volumetric evaluations of the oral cavity were also reported, and the reliability of CBCT was assessed. The use of CT resembled that of CBCT. Conclusion: CBCT has been used in the evaluation of tongue and oral cavity volumes to assess correlations between those volumes and with the upper airway. It has also been used for volumetric evaluation after surgical and nonsurgical procedures and to assess the relationships between tongue volume, tooth position, occlusion, and body mass index. Participants with obstructive sleep apnea and malocclusion have been evaluated, and the reliability of CBCT has been assessed. In the included studies, CT was utilized for similar purposes as CBCT, but its reliability was not assessed.

• Imaging Science in Dentistry
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• 제43권3호
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• pp.197-200
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• 2013

Florid osseous dysplasia (FOD) is an uncommon, benign, cemento-osseous lesion of the jaws. The etiology of FOD is still unknown. It is often asymptomatic and may be identified on routine dental radiographs. The classic radiographic appearance of FOD is amorphous, lobulated, mixed radiolucent/radiopaque masses of cotton-wool appearance with a sclerotic border in the jaws. In our case the lesion was found incidentally on routine periapical radiographs taken for restored teeth and edentulous areas. For further and detailed examination, a panoramic radiograph and cone-beam computed tomograph (CBCT) were taken. The panoramic radiograph and CBCT revealed maxillary bilateral and symmetrical, non-expansile, well-defined, round, radiopaque masses in contact with the root of the maxillary right second molar and left first molar teeth. Our aim in presenting this case report was to highlight the importance of imaging in diagnosis of FOD.

• Imaging Science in Dentistry
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• 제39권2호
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• pp.99-102
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• 2009

Adenomatoid odontogenic tumor (AOT) is a tumor of odontogenic epithelium with varying degrees of inductive changes in the connective tissue. The common radiographic appearance of AOT is a unilocular radiolucency associated with an unerupted tooth. Detectable radiopacities have been reported in many cases. We present a case of AOT in a 9-year old-female patient. Cystic lesion with numerous, punctuate radiopaque foci was observed on the anterior region of the mandible. These radiopacities were situated mostly on the buccal side of impacted tooth on the multi-planar images of cone beam computed tomograph. Characteristic duct like structures and amyloid like material were observed on histopathologic finding. (Korean J Oral Maxillofac Radiol2009; 39 : 99-102)

• 대한치과교정학회지
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• 제39권1호
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• pp.6-17
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• 2009

본 연구의 목적은 레이저 스캔 디지털 모형과 콘 빔 CT (CBCT) 영상을 모형 분석에 사용할 수 있는지를 평가하는 것이었다. 이를 위해 인접면에 금속 수복물을 갖지 않는 영구치열기의 20명의 교정환자에서 CBCT 영상, 석고 모형, 디지털 모형을 제작하여 각각에서 모형 분석을 시행한 후 그 계측치들을 비교하였다. 연구 결과 디지털 모형과 석고 모형을 비교 시, 치아 폭경 계측치 차이의 평균은 0.01-0.20 mm였으며, 치열궁 길이 부조화 계측치 차이의 평균은 상악 0.41 mm, 하악 0.82 mm였고, Bolton 부조화 값 차이의 평균은 전치부에서 0.17 mm, 전체에서 0.44 mm로 나타났다. CBCT 영상과 석고 모형을 비교 시 치아 폭경 계측치 차이의 평균은 0.01-0.22 mm였으며, 치열궁 길이 부조화 계측치 차이의 평균은 상악 0.43 mm, 하악 0.32 mm였고, Bolton 부조화 값 차이의 평균은 전치부에서 0.35 mm, 전체에서 1.25 mm로 나타났다. 디지털 모형과 CBCT 영상의 모형 분석을 석고 모형의 모형 분석에 비교해 볼 때 몇몇 계측치 들에서 유의한 차이가 있었으나 그 차이가 크지 않으므로 임상에서 활용 가능할 것으로 판단된다.

• 대한소아치과학회지
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• 제39권1호
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• pp.51-57
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• 2012

어린이는 8-10세 경에 외상을 자주 받으며 구강 내에서는 상악 절치부가 호발하는 부위이다. 외상으로 인하여 상악 절치가 상실되면 어린이에게 합병증을 야기할 수 있으므로 가능한 한 상악 절치를 유지해야 하지만 조기 상실되는 경우가 있다. 상악절치의 조기 상실로 인한 합병증으로는 심미적 문제나 치조골의 수직적 높이와 수평적 너비의 감소, 인접치의 경사, 악궁 장경 감소 등이 있다. 그 중에서 치조골이 소실되면 보철적 수복 시에 기능성과 안정성, 심미적인 면에 영향을 준다. 이 증례는 외상으로 인하여 상악 중절치가 조기 상실된 9세 여아와 6세 남아에서 각각 5년 5개월, 3년 7개월 후의 치조골소실 정도를 cone beam computed tomography와 진단 모형 상에서 관찰하였기에 보고하는 바이다.