하악관 위치 분석시 일반단층사진과 전산화단층사진의 비교연구

최항문,유동수 大韓口腔顎顔面 放射線學會 1995 Imaging Science in Dentistry Vol.25 No.2

The purpose of this study was comparision of conventional tomography with reformatted computed tomography for dental implant in locating the mandibular canal. Five dogs were used and after conventional tomographs and reformatted computed tomographs were taken, four dentist traced all films. Mandibles were sectioned with 2mm slice thickness and the sections were then radiographed(contact radiography). Each radiographic image was traced and linear measurements were made from mandibular canal to alveolar crest, buccal cortex, lingual cortex, and inferior border. Following results were acquired : 1. Reformatted computed tomographs were exacter than conventional tomography by alveolar crest to canal length of -0.6mm difference between real values and radiographs. 2. The average measurements of buccal cortex to mandibular canal width and lingual cortex to mandibular canal width of conventional tomographs were exacter than reformatted computed tomographs, but standard deviations were higher than reformatted computed tomographs. 3. Standard deviations of reformatted computed tomographs were lower than conventional tomographs at all comparing sites 4. At reformatted computed tomography 62.5% of the measurements performed were within ±1mm of the true value, and at conventional tomography 24.1% were. 5. Mandibular canal invisibility was 0.8% at reformatted computed tomography and 9.2% at conventional tomography. Reformatted computed tomography has been shown to be more useful radiographic technique for assessment of the mandibular canal than conventional tomography.

하악 제1대구치의 치근 만곡에 영향을 주는 요인

최항문,이원진,허민석,이삼선,김정화,최순철,박태원 대한구강악안면방사선학회 2006 Imaging Science in Dentistry Vol.37 No.1

Purpose : To find the cause of root curvature by use of panoramic and lateral cephalometric radiograph. Materials and Methods : Twenty six 1st graders whose mandibular 1st molars just emerged into the mouth were selected. Panoramic and lateral cephalometric radiograph were taken at grade 1 and 6, longitudinally. In cephalometric radio graph, mandibular plane angle, ramus-occlusal plane angle, gonial angle, and gonion-gnathion distance (Go-Gn distance) were measured. In panoramic radio graph, elongated root length and root angle were measured by means of digital subtraction radiography. Occlusal plane-tooth axis angle was measured, too. Pearson correlations were used to evaluate the relationships between root curvature and elongated length and longitudinal variations of all variables. Multiple regression equation using related variables was computed. Results : The Pearson correlation coefficient between curved angle and longitudinal variations of occlusal plane-tooth axis angle and ramus-occlusal plane angle was 0.350 and 0.401, respectively (p<0.05). There was no significant correlation between elongated root length and longitudinal variations of all variables. The resulting regression equation was Y=10.209+0.208X_(1)+0.745X_(2) (Y: root angle, X_(1): variation of occlusal plane-tooth axis angle, X_(2): variation of ramus-occlusal plane angle). Conclusion: It was suspected that the reasons of root curvature were change of tooth axis caused by contact with 2nd deciduous tooth and amount of mesial and superior movement related to change of occlusal plane. (Korean J Oral Maxillofac Radiol 2006; 36 : 55-62)

치아우식중 진단시 임상검사와 파노라마방사선사진검사의 탐지능 비교

최항문 大韓口腔顎顔面 放射線學會 1999 Imaging Science in Dentistry Vol.29 No.1

Purpose: The objective of this study was to compare clinical examination of dental caries and secondary caries with panoramic examination, and to examine bone lesions and dental anomaly of unerupted state. Materials and Methods: In this study, clinical records and panoramic radiographs were available for 89 first grade students in elementary school. Dental caries of occlusal surfaces, proximal surfaces, and buccolingual surfaces were examined. Secondary caries was examined too. In addition, the central lesion and dental anomaly of unerupted state were examined in panoramic radiographs. Results: The obtained results were as followed: 1. Carious detectability of clinical examination in occlusal and buccolingual surface was higher than that of panoramic examination, but it is statistically insignificant(p>0.05). In proximal surface, carious detectability of panoramic examination was higher than that of clinical examination, and it is statistically significant(p<0.01). 2. In contrast to clinical examination only, when the two examination methods were combined, there was additional detection of dental caries(26.7% in occlusal surface, 48.2% in proximal surface, 33.3% in buccolingual surface, and 38.3% totally). 3. In detection of secondary caries, panoramic examination had lower ability than clinical examination in all three surfaces, but in case that both methods were combined, totally 36.0% extra carious lesions were detected. 4. In panoramic examination, detectability of secodary caries in upper teeth is lower than lower teeth. 5. In panoramic examination, it was possible to detect the central lesions and dental anomalies of unerupted state which cannot be detected in clinical examination. Conclusion: It is useful to combine the panoramic examination with clinical examination in order to increase carious detectability and to evaluate the central lesions and dental anomalies of unerupted state.(J Korean Oral Maxillofac Radiol 1999:29:273-280)

전악치근단방사선사진촬영, 파노라마방사선사진촬영 및 협각단층촬영시의 흡수선량

최순철,최항문 大韓口腔顎顔面 放射線學會 1999 Imaging Science in Dentistry Vol.29 No.1

Purpose: The objective of this study was to evaluate the possibility of substitution of the zonography for the full-mouth periapical radiography in aspect of radiation protection. Materials and Methods: Rando phantom and LiF TLD chips were used for dosimetry. The absorbed doses at brain, skin above the TMJ, parotid gland, bone marrow in the mandibular body, and thyroid gland during the full-mouth periapical radiography, panoramic radiography, and zonography were measured. Results: From the zonography, the absorbed doses to the brain, the skin over the TMJ, and the parotid gland were relatively high, but the absorbed doses to the bone marrow in the mandibular body and, especially, the thyroid gland were very low. Conclusion: The zonography can be an alternative to the full-mouth periapical radiography in aspect of radiation protection.(J Korean Oral Maxillofac Radiol 1999:29:253-258)

파노라마방사선사진에서의 하악관의 각도와 이공의 위치에 관한 연구

최항문 대한구강악안면방사선학회 2009 Imaging Science in Dentistry Vol.39 No.2

Purpose : To assess the angle between mandibular canal and occlusal plane at each posterior tooth region and location of mental foramen on the panoramic radiographs. Materials and Methods : This study analysed 46 half-mandibles of panoramic radiographs. Inferior border of mandibular canal was traced. Occlusal plane was drawn from lingual cusp tip of the first premolar to distolingual cusp tip of the second molar. Perpendicular line from occlusal plane was drawn at each tooth region and then tangential lines were drawn from the crossing points at canal. the angle between occlusal plane and tangential line was measured. The location of mental foramen was also studied. According to the location of mental foramen, radiographs were divided into M (mesial) group and D (distal) group on the basis of the second premolar. and then inter-group analysis about mandibular canal angle was done. Results : The angles of mandibular canals were -17.7°, -9.5°, 8.2°, 22.3°, and 39.2° at first premolar, second premolar, first molar, second molar, and third molar, respectively. The commonest position of the mental foramen was distal to the second premolar. Inter-group comparison showed statistically significant difference at the second premolar and the first mo1ar(p<0.001). Conclusion : The knowledge of mandibular canal angle and location of mental foramen can help understanding the course of mandibular canal.

도시속의 자연경관보전을 위한 도시계획관련 법과 제도에 관한 연구

김항집,최봉문,이건호 牧園大學校 建築·都市硏究센터 1995 建築·都市環境硏究 Vol.3 No.-

Recently, the desire for better quality of urban environment go on increasing rapidly because the provlems of environment become more seriously in all around the world. And also because of the change of social concepts, the importance of urban landscape which is perceived as one of main factors of amenity in city grows significally. But Urban Planning Systems and Laws in Korea do not provide the effective tools to preserve urban landscape. So, in this paper, we try to find some methods tho preserve urban landscape by the means of Urban Planning System and Law System.

구외 방사선사진 촬영에 사용되는 기준선의 상호 관계

이설미,최항문 大韓口腔顎顔面 放射線學會 2001 Imaging Science in Dentistry Vol.31 No.4

Purpose : The aim of present study is to estimate the relationship among reference lines used for taking the extraoral radiography and panoramic radiography. Materials and Methods : Lateral cephalographs of 40 adults, aged 22 to 30 years were taken. Angles between reference lines (Frankfort line, canthomeatal line, infraorbitomeatal line, and occlusal plane) were measured. Results : Angles between Frankfort line and canthomeatal line, Frankfort line and infraorbitomeatal line, Frankfort line and occlusal plane, canthomeatal line and infraorbitomeatal line, canthomeatal line and occlusal plane, and infraorbitomeatal line and occlusal plane were 16.1°(±2.2), 5.8°(±2.4), 8.7°(±3.5), 10.3°(±1.3), 24.8°(±4.0), and 14.5°(±4.4), respectively. Conclusion : Angle between frankfort and canthomeatal line is very different with commonly known angle. Frankfort horizontal reference lines used for panoramic radiography need an exact definition and more accurate standard is needed for the taking of panoramic radiograph (Korean J Oral Maxillofac Radiol 2001; 31 : 205-7)

방사선 조사가 배양된 조골세포의 apoptosis와 세포주기의 변화 및 석회화 결절 형성에 미치는 영향에 관한 연구

이영미,최항문,허민석,이삼선,최순철,박태원 대한구강악안면방사선학회 2000 Imaging Science in Dentistry Vol.30 No.3

Purpose : The study was aimed to detect the induction of apoptosis, cell cycle arrest and calcified nodule formation after irradiation on primarily cultured osteoblasts. Materials and Methods : Using rat calvarial osteoblasts, the effects of irradiation on apoptosis, cell cycle arrest, and calcified nodule formation were studied. The single irradiation of 10 and 20 Gy was done with 5.38 Gy/min dose rate using the 137Cs cell irradiator at 4th and 14th day of culture. Apoptosis induction and cell cycle arrest were assayed by the flowcytomtry at 1,2,3, and 4 days after irradiation. The formation of calcified nodules was observed by alizarin red staining at 1,3,10,14 days after irradiation at 4th day of culture, and at 1,4,5 days after irradiation at 14th day of culture. Results : Apoptosis was not induced by 10 or 20 Gy independent of irradiation and culture period. Irradiation did not induced Gl arrest in post-irradiated ostedblasts. After irradiation at 4th-day of culture, G2 arrest was induced but it was not statistically significant after irradiation at 14th-day of culture. In the case of irradiated cells at 4th day of culture, calcified nodules were not formed and at 14th-day of culture after irradiation, calcified nodule formation did not affected. Conclusion : Taken together, these results suggest that Irradiation at the dose of 10-20 Gy would not affect apoptosis induction of osteoblasts. Cell cycle and calcified nodule formation were influenced by the level of differentiation of osteblasts. (Korean J Oral Maxillofac Radiol 2000; 30: 189-198)

6세 아동을 위한 파노라마방사선사진 상층의 연구

김상연,최항문,한진우,이설미 대한구강악안면방사선학회 2004 Imaging Science in Dentistry Vol.34 No.2

Purpose : To make a focal trough (image layer) for an average maxillary dental arch of 6-year-old korean in panoramic radiography. Materials and Methods : Phantom for the maxillary dental arch was designed using intercanine width, intermolar width, tooth size, and interdental spacing to record the data of 6-year-old child. The characteristics of pre-corrected panoramic machine (for adult) was evaluated using the phantom, resolution test pattern for margin of the image layer, and metal ball for the center of the image layer. Panoramic image layer of the child was developed by means of decreasing the speed of film-cassette and positioning the phantom backwards, and then the characteristics of post-corrected panoramic machine (for child) were reevaluated. Results : At post-corrected panoramic image layer, beam projection angles at all interdental areas increased for about 2.6-3.8.., the position of the image layer was shifted toward the rotation center for about 2.5 mm at the deciduous central incisior area. The width of image layer decreased at all areas. Conclusion : Increased beam projection angle will reduce the disadvantage of tooth overlap, and the same form between the center of the image layer and dental arch will improve image resolution.

하치조신경을 포함하는 발육성 타액선골결손

한진우,최항문 대한구강악안면방사선학회 2004 Imaging Science in Dentistry Vol.34 No.3

The present study reports a case of developmental salivary gland defect. On panoramic examination, large radiolucent lesion surrounded by a sclerotic wall was noted in the right posterior mandible. On CT examination, large lingual bone concavity with extra-osseous course of the inferior alveolar nerve bundle was detected. In atypical cases, it is suggested that confirmatory imaging using CT or MRI should be taken.