하악 무치악 부위의 임플란트 이식을 위한 전산화단층촬영 영상의 비교 평가

선경훈,정호걸,박혁,박창서,김기덕 대한구강악안면방사선학회 2009 Imaging Science in Dentistry Vol.39 No.1

Purpose : The purpose of this study was to evaluate the clinical usefulness of the recently developed multi-detector computed tomography and cone beam computed tomography in pre-operative implant evaluation, by comparing them with the single detector computed tomography, already confirmed for accuracy in this area. Materials and Methods : Five partially edentulous dry human mandibles, with 1×1 mm gutta percha cones, placed in 5 mm intervals posterior to the mental foramen on each side of the buccal part of the mandible, were used in this study. They were scanned as follows: 1) Single detector computed tomography: slice thickness 1 mm, 200 mA, 120 kV 2) Multi-detector computed tomography: slice thickness 0.75 mm, 250 mA, 120 kV 3) Cone beam computed tomography: 15 mAs, 120 kV Axial images acquired from three computed tomographies were transferred to personal computer, and then reformatted cross-sectional images were generated using V-Implant 2.0 (CyberMed Inc., Seoul, Korea) software. Among the cross-sectional images of the gutta percha cone, placed in the buccal body of the mandible, the most precise cross section was selected as the measuring point and the distance from the most superior border of the mandibular canal to the alveolar crest was measured and analyzed 10 times by a dentist. Results : There were no significant intraobserver differences in the distance from the most superior border of the mandibular canal to the alveolar crest (p>0.05). There were no significant differences among single detector computed tomography, multi-detector computed tomography and cone beam computed tomography in the distance from the most superior border of the mandibular canal to the alveolar crest (p>0.05). Conclusion : Multi-detector computed tomography and cone beam computed tomography are clinically useful in the evaluation of pre-operative site for mandibular dental implants, with consideration for radiation exposure dose and scanning time.

Cone beam형 전산화단층영상에서 골의 형태와 밀도의 평가

홍상우,김규태,최용석,황의환 대한구강악안면방사선학회 2008 Imaging Science in Dentistry Vol.38 No.1

Purpose : Diagnostic estimation of destruction and formation of bone has the typical limit according to capacity of x-ray generator and image detector. So the aim of this study was to find out how much it can reproduce the shape and the density of bone in the case of using recently developed dental type of cone beam computed tomography, and which image is applied by new detector and mathematic calculation. Materials and Methods : Cone beam computed tomography (PSR 9000N, Asahi Roentgen Ind. Co., Ltd., Japan) and soft x-ray radiography were executed on dry mandible that was already decalcified during 5 hours, 10 hours, 15 hours, 20 hours, and 25 hours. Estimating and comparing of those came to the following results. Results : The change of inferior border of mandible and anterior border of ramus in the region of cortical bone was observed between first 5 and 10 hours of decalcification. The reproduction of shape and density in the region of cortical bone and cancellous bone can be hardly observed at cone beam computed tomography compared with soft x-ray radiography. The difference of decrease of bone density according to hours of decalcification increase wasn’t reproduced at cone beam computed tomography compared with soft x-ray radiography. Conclusion : CBCT images revealed higher spatial resolution. However, contrast resolution in region of low contrast sensitivity is the inferiority of images’ property.

하악 제3대구치와 하악관과의 위치관계에 대한 파노라마 방사선사진과 cone beam형 전산화단층영상의 비교

최형수,김규태,최용석,황의환 대한구강악안면방사선학회 2008 Imaging Science in Dentistry Vol.38 No.3

Purpose : To assess the diagnostic accuracy and value in an imaging technique field through the comparison of cone beam computed tomography and conventional panoramic radiography in assessing the topographic relationship between the mandibular canal and impacted third molars. Materials and Methods : Participants consisted of 100 patients offered the images through cone beam computed tomography and panoramic radiography. PSR-9000 Dental CT system (Asahi Roentgen Ind. Co., Ltd, Japan) was used as the unit of cone beam computed tomography. CE-II (Asahi Roentgen Ind. Co., Ltd, Japan) and Pro Max (Planmeca Oy, Finland) were used as the unit of panoramic radiography. The images obtained through panoramic radiography were classified into 3 types according to the distance between mandibular canal and root of mandibular third molar. And they were classified into 4 types according to the proximity of radiographic feature. The images obtained through cone beam computed tomography based on the classification above were classified into 4 types according to the location between the mandibular canal and the root and were analyzed. And they were classified into buccal, inferior, lingual, and between roots, according to the location between mandibular canal and root. The data were statistically analyzed and estimated by χ²-test. Results : 1. There was no statistical significance according to 3 types (type l, type ll, type lll) through CBCT. 2. The results of 4 types (type A, type B, type C, type D) through CBCT were as high prevalence of CBCT 1 in type A, CBCT 2 in type B, CBCT 3 in type C, and CBCT1 in type D and those of which showed statistical significance (P value=0.03). 3. The results according to location between mandibular canal and root through CBCT recorded each 49, 25, 17, 9 as buccal, inferior, lingual, between roots. Conclusion : When estimating the mandibular canal and the roots through the panoramic radiography, it could be difficult to drive the views of which this estimation was considerable. Thus it is required to have an accurate diagnostic approaching through CBCT that could estimate the location between mandibular canal and roots.

골결손부 치유과정에서 cone beam형 전산화단층영상의 정확도

강호덕,김규태,최용석,황의환 대한구강악안면방사선학회 2007 Imaging Science in Dentistry Vol.37 No.2

Purpose : To evaluate the accuracy of the imaging reformation of cone beam computed tomography for the assessment of bone defect healing in rat model. Materials and Methods : Sprague-Dawley strain rats weighing about 350 gms were selected. Then critical size bone defects were done at parietal bone with implantation of collagen sponge. The rats were divided into seven groups of 3 days, 1 week, 2 weeks, 3 weeks, 4 weeks, 6 weeks, and 8 weeks. The healing of surgical defect was assessed by multiplanar reconstruction (MPR) images and three-dimensional (3-D) images of cone beam computed tomography, compared with soft X-ray radiograph and histopathologic examination. Results : MPR images and 3-D images showed similar reformation of the healing amount at 3 days, 1 week, 2 weeks, and 8 weeks, however, lower reformation at 3 weeks, 4 weeks, and 6 weeks. According to imaging-based methodologies, MPR image revealed similar reformation of the healing amount than 3-D images compare with soft X-ray image. Among the four threshold values for 3-D images, 400-500 HU revealed similar reformation of the healing amount. Histopathologic examination confirmed the newly formed trabeculation correspond with imagingbased methologies. Conclusion : MPR images revealed higher accuracy of the imaging reformation of cone beam computed tomography and cone beam computed tomography is a clinically useful diagnostic tool for the assessment of bone defect healing.

방사선치료용 선형가속기를 이용한 Gated Cone-Beam CT의 유용성 연구

서정민(Seo, Jeong-Min),김찬형(Kim, Chan-Hyeong),박병석(Park, Byoung-Suk),박철수(Park, Cheol-Soo),장현철(Jang, Hyon-Chol),김정대(Kim, Joung-Dae) 한국산학기술학회 2015 한국산학기술학회논문지 Vol.16 No.10

환자의 호흡은 방사선치료에서 중요한 인자로 작용한다. 종양을 치료하는 방사선 치료용 선형가속기에서 시행하는 기존의 cone-beam CT에서는 호흡에 의한 움직임이 반영되지 않아 영상에 왜곡이 발생하여 정확하지 못한 영상 정보를 획득 하였다. 본 연구는 호흡에 의한 움직임을 고려하고 특정 순간을 포착한 gating을 적용하여 획득한 back projection 영상을 이용 하여 cone-beam CT 영상으로 재구성하였으며 기존의 방법과 비교하였다. 기존의 방법은 영상 왜곡도가 400%에 달하였으나, 본 연구에서 시행한 gating을 적용한 cone-beam CT는 약 2%에 불과하였다. 이에 본 연구는 호흡의 움직임을 반영한 영상유도 방사선치료의 방향과 평가 방법을 제시하였다. The respiration is one of important factor in the radiation therapy. The existing commercial method of cone-beam computed tomography on LINAC does not consider respiratory motion of patient hence the images are both distorted and inaccurate. In this study, the cone-beam computed tomography images have been reconstructed from back projection radiography of specific phase on breathing cycle which concerned about respiratory movement in radiation therapy. This study investigated how different between cone-beam CT images with and without gating respiratory movement, and this paper provides that guide and implementation of gated cone-beam CT on radiation therapeutic equipment.

Endodontic treatment of tooth with morphological anomalies using cone-beam computed tomography

( Sung-hyeon Choi ),( Na-kyung Yoon ),( Ji-hyun Jang ),( Young-hoon Kim ),( Hoon-sang Chang ),( Yun-chan Hwang ),( In-nam Hwang ),( Won-mann Oh ),( Bin-na Lee ) 조선대학교 구강생물학연구소 2018 Oral Biology Research (Oral Biol Res) Vol.42 No.1

The aim of this study is to describe the endodontic treatment of a radix entomolaris (RE) with the C-shaped canal in mandibular first molar and a fused maxillary premolar with two supernumerary teeth with the separated root canal using cone-beam computed tomography imaging (CBCT). In our cases, non-surgical endodontic treatment based on the results of CBCT diagnosis, ProTaper rotary system, hand instrumentation, and passive ultrasonic irrigation along with periodontal treatment resulted in long-term and successful prognosis. Therefore, CBCT analysis an effective diagnostic tool for the treatment of teeth containing complex root canals.

Clinical study and statistical analysis of intrabony location of posterior superior alveolar artery using cone-beam computed tomography

( In-sook Park ) 조선대학교 구강생물학연구소 2017 Oral Biology Research (Oral Biol Res) Vol.41 No.4

The posterior superior alveolar artery (PSAA) is the branch of the maxillary artery that supplies the lateral sinus wall and overlying membrane. This artery has the potential to cause bleeding complications in approximately 20% of normally positioned lateral window osteotomies. The aim of this clinical study was to evaluate prevalence, diameter, and location of the PSAA before sinus augmentation using cone-beam computed tomography (CBCT). Sixty-nine CBCT scans from 18 patients undergoing lateral sinus augmentation and implant placement using a thin saw insert with a piezoelectric surgical device were included. Distance of the arterial inferior border from the alveolar crest, diameter, and horizontal position of the artery were statistically analyzed. Sinus membrane perforation and arterial damage were recorded at the creation of the lateral bony window. The artery was identified in 63.9% and was mostly intraosseous (53.62%). The average distance between the alveolar crest and the inferior border of the PSAA was 16.34±5.67 mm; the lowest border was located at maxillary first molar (p = .056). The mean diameter of the PSAA was 1.14±0.45 mm. Significant positive correlation between diameter and age was observed (p = .015^*). The results from this study suggest that evaluation of the PSAA is needed before sinus augmentation, especially in elderly edentulous patients. Use of a piezoelectric surgical device can reduce the incidence of potential vascular damage and sinus membrane perforation due to micro-vibration. For these reasons, the creation of a lateral bony window during sinus augmentation is recommended.

Multiple intraosseous cervical pneumatocysts: A case report of a rare incidental finding on cone-beam computed tomography

Jadhav, Aniket B.,Sarah, Sangeetha Gajendran,Cederberg, Robert,Wagh, Aditya,Kiat-amnuay, Sudarat Korean Academy of Oral and Maxillofacial Radiology 2018 Imaging Science in Dentistry Vol.48 No.3

This report presents a case of cervical pneumatocysts as an incidental finding on cone-beam computed tomography. Pneumatocysts are gas-containing lesions of unknown etiology. They usually present in the ilium or sacrum, adjacent to the sacroiliac joint. In the literature, 21 case reports have described cervical pneumatocysts. Cervical pneumatocysts should be differentiated from other lesions, such as osteomyelitis, osteonecrosis, and neoplasms, as well as post-traumatic and post-surgical cases. Computed tomography, cone-beam computed tomography, and magnetic resonance imaging are appropriate tools to diagnose cervical pneumatocysts.

Cone-beam computed tomography 영상에서의 쇄골두개형성이상

이근선 ( Gun Sun Lee ),김재덕 ( Jae Duk Kim ) 조선대학교 구강생물학연구소 2012 Oral Biology Research (Oral Biol Res) Vol.36 No.1

Cleidocranial dysplasia is a rare autosomal dominent disorder characterized by aplasia or hypoplasia of the clavicles, an open fontanelle, and dental abnormalities. We present the case of an 11-year-old female with short stature and mixed dentition. The patient demonstrated abnormal hypermobility of the shoulder, ocular hypertelorism, and a concave nasal bridge. Examination of panoramic imagesrevealed some morphological abnormalities of the maxilla and mandible, particularly in the ascending ramus and coronoid process. Characteristics includingwide discontinuity of the zygomatic arch, wide nose bridge, near parallel-sided borders of the ascending ramus of the mandible, and obtuse mandibular angle were confi rmed by 3-dimensional imaging using cone-beam computed tomography.

Three-dimensional evaluation of the relationship between nasopharyngeal airway shape and adenoid size in children

Oh, Kyung-Min,Kim, Min-Ah,Youn, Jong-Kuk,Cho, Hyung-Jun,Park, Yang-Ho The Korean Association Of Orthodontists 2013 대한치과교정학회지 Vol.43 No.4

Objective: To evaluate the shapes and sizes of nasopharyngeal airways by using cone-beam computed tomography and to assess the relationship between nasopharyngeal airway shape and adenoid hypertrophy in children. Methods: Linear and cross-sectional measurements on frontal and sagittal cross-sections containing the most enlarged adenoids and nasopharyngeal airway volumes were obtained from cone-beam computed tomography scans of 64 healthy children ($11.0{\pm}1.8$ years), and the interrelationships of these measurements were evaluated. Results: On the basis of frontal section images, the subjects' nasopharyngeal airways were divided into the following 2 types: the broad and long type and the narrow and flat type. The nasopharyngeal airway sizes and volumes were smaller in subjects with narrow and flat airways than in those with broad and long airways (p < 0.01). Children who showed high adenoid-nasopharyngeal ratios on sagittal imaging, indicating moderate to severe adenoid hypertrophy, had the narrow and flat type nasopharyngeal airway (p < 0.01). Conclusions: Cone-beam computed tomography is a clinically simple, reliable, and noninvasive tool that can simultaneously visualize the entire structure and a cross section of the nasopharyngeal airway and help in measurement of adenoid size as well as airway volume in children with adenoid hypertrophy.