Application of simulated three dimensional CT image in orthognathic surgery

치의학과/박사[한글] 치아 교정 및 악교정 수술 분야에서 두개안면 골격 형태의 진단 및 치료평가에 두부규격 방사선사진이 널리 사용되고 있으나 입체적인 구조물을 평면적으로 나타냄으로 인해 평가시 정확하지 못한 결과를 초래할 수 있다. 따라서 구조물은 입체적인 상으로 나타내는 것이 바람직하며 이를 위해서는 3차원 전산화 단층촬영이 가장 좋은 방법이다. 임상을 위해서는 치료 결과의 평가와 치료 전후의 비교 분석이 필요하며 따라서 수술 전에 3차원 전산화 단층촬영을 하여 진단과 치료 계획을 세워 수술한 환자는 수술 후에도 3차원 전산화 단층촬영을 하여 수술 전후를 입체적으로 평가한다면 더욱 정확한 비교와 평가를 할 수 있다. 그러나 3차원 좌표계로부터의 정상치에 대한 표준화된 연구 결과가 없어 임상에 적용하기 어렵고 또한 고가의 장비 및 비용과 방사선 피폭량 등의 문제로 인해 많은 장점에도 불구하고 3차원 전산화 단층상은 널리 사용되지 못하고 있다. 저자는 악교정 수술 전후의 후전방 및 측방 두부규격 방사선사진에서의 변화를 악교정 수술 전의 3차원 전산화 단층상에 적용하여 모의 조종된 3차원상을 얻는 새로운 방법을 만들어 보았고 이 방법을 검증하고자 악교정 수술을 가상하여 하악골의 위치를 변화시킨 건조 두개골의 4 가지 경우와 악교정 수술을 받은 4 명의 환자에 적용하여 보아 다음과 같은 결과를 얻었다. 1. 하악골의 위치를 달리하고 시행된 건조 두개골의 4 가지 경우에서 하악골의 위치 변화 전후의 후전방 및 측방 두부규격 방사선사진에서의 변화를 하악골의 위치 변화 전의 3차원 상에 적용하여 컴퓨터로 모의 조종된 3차원 상과 하악골의 위치 변화 후에 실제 촬영된 3차원 상 간의 좌표값의 변위 범위는 -1.8 mm에서 1.8 mm까지였고 모든 변위값의 94%가 -1.4 mm에서 1.4 mm까지였으며 또한 두 상 간에 유의차는 없었다(p>0.05). 2. 악교정 수술을 받은 4 명의 환자에서 수술 전후의 후전방 및 측방 두부규격 방사선 사진에서의 변화를 수술 전의 3차원 상에 적용하여 컴퓨터로 모의 조종된 3차원 상과 수술 후에 실제 촬영된 3차원 상 간의 좌표값의 변위 범위는 -6.7 mm에서 7.7 mm까지였고 모든 변위값의 90%가 -4.0 mm에서 4.0 mm까지였으며 또한 두 상 간에 유의차는 없었다(p>0.05). 결론적으로 수술 전의 3차원 전산화 단층사진과 수술 전후의 후전방 및 측방 두부규격 방사선사진을 이용하여 컴퓨터로 모의 조종된 3차원 상을 얻어 건조 두개골과 악교정 수술 환자에 각각 적용한 결과 앞으로 수술 후에 3차원 전산화 단층촬영을 하지 않고도 수술 후의 3차원 상을 얻을 수 있는 가능성이 제시되었다. [영문] In orthodontics and orthognathic surgery, cephalogram has been routine practice in diagnosis and treatment evaluation of craniofacial deformity. But its inherent distortion of actual length and angles during projecting three dimensional object to two dimensional plane might cause errors in quantitative analysis of shape and size, Therefore, it is desirable that three dimensional object is diagnosed and evaluated three dimensionally and three dimensional CT image is best for three dimensional analysis. Development of clinic necessitates evaluation of result of treatment and comparison before and after surgery. It is desirable that patient that was diagnosed and planned by three dimensional computed tomography before surgery is evaluated by three dimensional computed tomography after surgery, too. But Because there is no standardized normal values in three dimension now and three dimensional Computed Tomography needs expensive equipments and because of its expenses and amount of exposure to radiation, limitations still remain to be solved in its application to routine practice. If postoperative three dimensional image is constructed by pre and postoperative lateral and postero-anterior cephalograms and preoperative three dimensional computed tomogram, pre and postoperative image will be compared and evaluated three dimensionally without three dimensional computed tomography after surgery and that will contribute to standardize normal values in three dimension. This study introduced new method that computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms, and for validation of new method, in four cases of dry skull that position of mandible was displaced and four patients of orthognathic surgery, computer-simulated three dimensional image and actual postoperative three dimensional image were compared. The results were as follows. 1. In four cases of dry skull that position of mandible was displaced, range of displacement between computer-simulated three dimensional images and actual postoperative three dimensional images in co-ordinates values was from -1.8 mm to 1.8 mm and 94% in displacement of all co-ordinates values was from -1.0 mm to 1.0 mm and no significant difference between computer-simulated three dimensional images and actual postoperative three dimensional images was noticed(P>0.05). 2. In four cases of orthognathic surgery patients, range of displacement between computer-simulated three dimensional images and actual postoperative three dimensional images in co-ordinates values was from -6.7 mm to 7.7 mm and 90% in displacement of all co-ordinates values was from -4.0 to 4.0 mm and no significant difference between computer-simulated three dimensional images and actual postoperative three dimensional images was noticed(P>0.05). Conclusively, computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms. Therefore, potentiality that can construct postoperative three dimensional image without three dimensional computed tomography after surgery was presented.restrictio

(The) study of comparison before and after orthodontic treatment in class I bialveolar protrusion cases with four bicuspid extraction

치의학과/석사[한글] 저자는 제 1 소구치 발치를 동반한 제 I 급 치조성 양악 전돌 환자의 석고 모형과 측모 두부 방사선 사진상에서의 치료 전후의 변화량을 알아보고 견치의 후방견인 방법(Sectional canine retraction과 Sliding canine retraction)과 anchorage의 보강(Head gear, Tr anspalatal arch와 Lingual arch)유무에 따른 전치와 구치의 이동양을 비교해 보고 또한 석고모형과 측모 두부 방사선 사진을 연관지어 치료기간 동안 발생된 변화 양상을 알아보고자 초진시 16세 이상의 여자환자 77명의 치료 전후의 석고 모형과 측모 두부 방사선 사 진을 대상으로 조사한 바 다음과 같은 결과를 얻었다. 1. 치료기간 중 대구치간 폭경, 치열궁 장경, 치열궁 주위 장결은 상하악 모두 치료 후에 유의성 있는 감소를 보였고 견치간 폭경은 상하악 모두 유의성 있는 차이를 보이지 않았다. 2. 상악 중절치(Ul)와 상순(Ls)의 이동 비율은 2.84 : 1이며 하악 중절치(Ll)와 하순(Li)의 이동 비율은 1.45 : 1 이었다. 3. 전치의 후방 이동양과 구치의 전방 이동양의 비교에서 견치의 후방 견인 방법(sectional canine retraction 대 sliding canine retraction)과 transpalatal arch나 lingual arch의 사용 유무에 따라서는 유의성 있는 차이가 없었으며 head gear를 사용한 군이 사 용하지 않은 군에 비해 전치의 후방 이동양은 유의성 있게 크게 나타났고 구치의 전방 이동양은 유의성 있게 작게 나타났다. 4. 치료 전후의 석고 모형을 통한 악궁 크기의 변화를 측모 두부 방사선 사진상에서의 변화와 연관지어 전치 견치 및 대구치의 변화양상을 알아본 바 다음과 같이 나타났다. 1) 상악 중절치는 후방으로 3.77mm 이동하였고, 견치는 외측으로 0.22mm 후방으로 3.70mm 이동하였으며 대구치는 내측으로 0.535mm 전방으로 2.29mm 이동하였다. 2) 하악 중절치는 후방으로 3.04mm 이동하였고, 견치는 외측으로 0.145mm 후방으로 3.92%mm 이동하였으며 대구치는 내측으로 0.755mm 전방으로 1.77mm 이동하였다. THE STUDY OF COMPARISON BEFORE AND AFTER ORTHODONTIC TREATMENT IN CLASS I BIALVEOLAR PROTRUSION CASES WITH FOUR BICUSPID EXTRACTION HYUNG DON KIM, D.D.S. Department of Dental science, Graduate School, Yonsei University (Directed by prof. Young-Ghel Park, D.D.S., Ph.D.) The purposes of present study were to evaluate changes in models and lateral cephalometric head films during orthodontic treatment and to compare the amount of incisal retraction and anterior movement of molars with the two approaches of the retraction method of canine(sectional canine retractions vs sliding canine retractions) and the anchorage management(head gears vs no head gears, transpalatal arches vs no transpalatal arches and lingual arches vs no lingual arches) and to evaluate changes during orthodontic treatment in models with relation to lateral cephalometric head films. 67 Korean women with Angle's Class I bialveolar protrusion were selected, whose initial chronologic age was above 16 yrs. Models and lateral cephalometric head films were taken before and after orthodontic treatment with four bicuspid extraction. the results were obtained as follows : 1. Significant decreases were observed in intermolar with, arch length and arch perimeter of maxilla and mandible but significant difference was not obserred in intercanine with of maxilla and mandible during treatment period. 2. The linear change of the upper incisor to upper lip was 2.84 : 1 and the linear change of the lower incisor t? lower lip was 1.45 : 1. 3. There were no significant differences between the two groups(sectional canine retractions vs sliding canine retractions), the two groups(transpalatal aches vs no transpalatal arches) and the two groups(lingual arches vs no lingual arches) in the amount of incisal retraction and anterior movement of molars. There were a greater amount of maxillary incisal retraction and a lesser amount of anterior movement of maxillary molars with the use of head gears than no use of head gears. 4. Changes during orthodontic treatment in models with relation to lateral cephalometric head films were obtained as follows : 1) maxilla Central incisors were moved 3.77mm backward, canines were moved 0.22mm laterally and 3.70mm backward, and molars were moved 0.57mm medially and 2.29mm forward. 2) Mandible Central incisors were moved 3,04mm backward, canines were moved 0.145mm laterally an d3.92mm backward, and molars were moved 0.755mm medially and 1.77mm forward. [영문] The purposes of present study were to evaluate changes in models and lateral cephalometric head films during orthodontic treatment and to compare the amount of incisal retraction and anterior movement of molars with the two approaches of the retraction method of canine(sectional canine retractions vs sliding canine retractions) and the anchorage management(head gears vs no head gears, transpalatal arches vs no transpalatal arches and lingual arches vs no lingual arches) and to evaluate changes during orthodontic treatment in models with relation to lateral cephalometric head films. 67 Korean women with Angle's Class I bialveolar protrusion were selected, whose initial chronologic age was above 16 yrs. Models and lateral cephalometric head films were taken before and after orthodontic treatment with four bicuspid extraction. the results were obtained as follows : 1. Significant decreases were observed in intermolar with, arch length and arch perimeter of maxilla and mandible but significant difference was not obserred in intercanine with of maxilla and mandible during treatment period. 2. The linear change of the upper incisor to upper lip was 2.84 : 1 and the linear change of the lower incisor t? lower lip was 1.45 : 1. 3. There were no significant differences between the two groups(sectional canine retractions vs sliding canine retractions), the two groups(transpalatal aches vs no transpalatal arches) and the two groups(lingual arches vs no lingual arches) in the amount of incisal retraction and anterior movement of molars. There were a greater amount of maxillary incisal retraction and a lesser amount of anterior movement of maxillary molars with the use of head gears than no use of head gears. 4. Changes during orthodontic treatment in models with relation to lateral cephalometric head films were obtained as follows : 1) maxilla Central incisors were moved 3.77mm backward, canines were moved 0.22mm laterally and 3.70mm backward, and molars were moved 0.57mm medially and 2.29mm forward. 2) Mandible Central incisors were moved 3,04mm backward, canines were moved 0.145mm laterally an d3.92mm backward, and molars were moved 0.755mm medially and 1.77mm forward.restrictio

A study on the role of AtcwINV1 in the plant response to cytokinin

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