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      • KCI등재

        정모두부방사선사진에서 하악골 우각부 영상확대 및 이의 보정에 관한 3차원 CT영상 연구

        황현식,,은춘선,황정현,임회정 대한치과교정학회 2005 대한치과교정학회지 Vol.35 No.4

        두부방사선규격사진은 작은 크기의 방사선원에서 방사상으로 방사선이 퍼져나감으로써 피사체의 확대와 왜곡이 불가피하다는 단점이 있다. 본 연구는 두 장의 방사선사진을 서로 직각으로 촬영한 후 방사선의 기하학적 성질을 이용하여 좌우 우각부간 폭경을 계산할 경우 실제 폭경의 산출이 가능한지 알아보고자 시행되었다. 성인 40명을 연구대상으로 하여 두부자세재현기를 이용하여 측모두부방사선사진과 정모두부방사선사진을 서로 직각으로 촬영한 후 측모사진과 정모사진에서의 확대율을 이용하여 실제 우각부 폭경을 산출한 다음, 계측치 및 산출치를 3차원 CT영상에서의 계측치와 각각 비교 분석하였다. 연구결과 정모두부방사선사진에서 우각부 폭경은, 작게는 7.92 mm 크게는 11.31 mm까지. 평균 9.10 mm의 확대를 보였다. 측모 및 정모두부방사선사진을 이용하여 얻은 우각부 폭경 보정치를 3차원 CT영상에서 얻은 기준치와 비교한 결과 평균 0.14 mm의 작은 오차를 보였으며 통계적으로 유의한 차이를 보이지 않아 측모 및 정모두부방사선사진 촬영 시 두부자세재현기를 이용하여 서로 직각으로 촬영할 경우 실제 우각부 폭경을 계산을 통해 산출할 수 있음을 보여주었다. 한편 이부편위량과 보정오차는 통계적으로 유의한 상관성을 보이지 않아 안면비대칭이 심한 경우에도 본 보정 방법이 유용하게 사용될 수 있음을 보여주었다. Enlargement is an inherent property of X-rays which occurs when straight lines diverge from small a focal spot. The purpose of the present study was to evaluate the valldity of the correction of gonial angle width enlarged on frontal cephalogram, using frontal and lateral cephalograms taken orthogonally from each other. In 40 adult individuals, frontal and lateral cephalograms were taken at a 90℃ angle using the Head Posture Aligner. The angle width was measured on the frontal cephalogram and subsequently, the corrected angle width was calculated using the magnification rate of two cephalograms. Measured and corrected angle widths were compared with the measurement from the 3D CT image. The measurement on the frontal cephalogram showed a 9.10 mm of enlargement on average, ranging from 7.92 to 11.31 mm. Corrected angle width measurement showed a 0.14 mm difference with the 3D CT image measurement, which was not statistically significant. The results of the study indicate that actual angle width can be approached through calculation using frontal and lateral cephalograms taken orthogonally with the help of the Head Posture Aligner. The study also showed that the magnitude of correction error did not show a significant correlation with the amount of menton deviation, and it suggests that the present correction method is valid even in individuals with severe facial asymmetry.

      • 백서에서 치아이동 후 보정기간 동안 교합이 치주조직 섬유의 재형성에 미치는 영향

        정권희,이기헌,황현식,이석형 전남대학교 치의학연구소 2002 구강과학 Vol.14 No.2

        The purpose of this study was to evaluate the effect of occlusion on the mechanical strength of periodontal fibers during retention periods after experimental tooth movement. In the Sprague-Dawley male rats weighing 200 g or more. The intraoral elastics was inserted into the interproximal space of upper the first and second molars. After 4th day of teeth movement, the left mandibular first, second, and third molars were extracted for differentiating the occlusal side from the non-occlusal side in the experimental groups. The intraoral elastics was removed and then light cured resin was placed in the interproximal space between the bilateral upper first and second molars following undercut was made for retention. From the day beginning retention, 7 rats were sacrified at 0, 4, 8, 12, 16, 20 days respectively. For evaluating of degree on the mechanical strength of periodontal tissue, maximal shear load of the bilateral upper first molars were measured by use of Instron Universal Testing Machine. The results of this study were obtained as follows: 1. In the occlusal side from no retention group to 4-day, 8-day, 12-day, 16-day, and retention 20-day group as time was going maximal shear load was increased and there was statistically difference from retention 12-day group(p<0.05). 2. In the non-occlusal side from no retention group to 4-day, 8-day, 12-day, 16-day, and retention 20-day group as time was going maximal shear load was increased slightly but there was no statistically difference(p>0.05). 3. The result compared with maximal shear load between occlusal and non-occlusal side showed no statistically difference until retention 8-daygroup(p>0.05), and showed statistically difference from retention 12-day to 20-day group(p<0.05). These results show that the occlusion had an effect on mechanical strength of the periodontal fibers during retention periods after experimental tooth movement; therefore, it is suggested that consideration of occlusion is required for the type and length of retention at the time of retention planning.

      • SCOPUSSCIEKCI등재

        치아돌출이 부착치은 폭경에 미치는 영향

        황현식,김종철,김정문 대한치과교정학회 1998 대한치과교정학회지 Vol.28 No.1

        치아돌출정도가 부착치은 폭경에 미치는 영향을 살펴보기 위하여 치주상태가 양호한 성인 중 하악 전치부에 다소의 총생이 있는 37명을 대상으로 하악의 인상채득 후 석고모형을 제작한 다음 각 하악 절치의 상대적 및 절대적 돌출정도를 측정하고 임상치관 고경, 치주낭 깊이, 각화 및 부착지은 폭경와 비교 분석하여 다음과 같은 결론을 얻었다. 1. 비돌출측에 비하여 돌출측은 각화치은 및 부착치은 폭경이 작게 나타났다. 2. 돌출측의 임상치관 고경은 비돌출측보다 유의하게 크게 나타났으나 치주낭 깊이는 돌출측과 비돌출측간의 유의한 차이를 보이지 않았다. 3. 돌출측과 비돌출측간의 부착치은 폭경차이는 중절치보다 측절치에서 더욱 뚜렷이 나타났다. 4. 절대적 돌출도보다 상대적 돌출도가 부착지은 폭경과 더 높은 상관관계를 나타내었다. 5. 돌출도보다 임상치관고경이 부착치은 폭경과 더 높은 상관관계를 나타내었다. The purpose of the present study was to evaluate the effect of incisor protrusion on the mucogingival parameters including the width of attached gingiva. Thirty-seven young adults with lower anterior crowding were selected for this study. From the study model, the degrees of relative and absolute protrusions were measured for each lower incisor. Clinical crown height, the width of keratinized gingiva, probing depth and the width of attached gingiva were measured with digital vernier calipers and Florida Probe System. Through comparing the difference of the above measurements between protruded and non-protruded incisors, and correlation analysis between each measurement, following results were obtained: 1. The protruded incisor showed narrow width of keratinized and attached gingive comparing to non-protruded incisor. 2. The protruded incisor showed greater clinical crown height comparing to non-protruded side while there was no difference in the probing depth between protruded and non-protruded side. 3. The difference in the width of attached gingiva between protruded and non-protruded incisors showed higher significance in the lateral incisor than in the central incisor. 4. The degree of relative protrusion showed higher correlation with the width of attached gingiva than the degree of absolute protrusion. 5. Clinical crown height showed higher correlation with the width of attached gingiva than the degree of protrusion.

      • 치커리와 쑥갓의 무균자엽절편체 생산 효율 증진

        황현정,전혜정,최근원,김영채 경희대학교식량자원개발연구소 2005 硏究論文集 Vol.24 No.-

        치커리와 쑥갓에 있어 식물조직배양이나 형질전환 과정에 필요한 무균 절편체를 얻기 위한 적절한 방법을 제안하기 위해 기내 파종을 위한 소독조건과 배지조성 및 종류에 관한 실험들이 실시되었다. 치커리 'Precole'은 10% NaOCl, 15분간, 'Chiavari'는 5% NaOCl, 15분간이 기내파종 시 발아 및 자엽전개를 촉진시키고 오염발생을 억제하는 조건으로 선발되었다. 쑥갓에서는 발아 및 자엽전개율에 있어 NaOCl 처리 간에 차이는 없었지만 10% NaOCl, 30분간 처리에서 가장 낮은 오염율이 관측되었다. 치커리와 쑥갓의 발아와 자엽전개율 모두 인조토양배지의 사용으로 MS 배지에 비해 현저히 향상 되었다. 비록 육안으로는 오염여부를 관측할 수는 없었지만 이들 인조토양배지에서 자란 쑥갓 묘의 자엽을 MS배지에 치상하여 배양 시에는 오염증상이 나타났으며 이들을 NaOCl 1%로 15분간 소독 후 치상한 결과 오염율을 현저히 낮출 수 있었다. Experiments on the sterilization condition and medium composition and type for in vitro sowing were conducted to suggest a proper way to produce enough aseptic explants for tissue culture or transformation study in chicory and garland chrysanthemum. Fifteen minutes soaking treatment with 10% NaOCl for chicory 'Precole' and 15 minutes with 5% NaOCl for chicory 'Chiavari' were selected as proper sterilization conditions to promote in vitro germination and cotyledon expansion and inhibit the seedling contamination from seed itself. In garland chrysanthemum, there was no significant difference in germination and cotyledon expansion ratio among NaOCl treatments, but the lowest seedling contamination ratio was observed by 30 minutes soaking with 10% NaOCl. Both germination and cotyledon expansion ratio in chicory and garland chrysanthemum were significantly increased by using the artificial soil media in contrast to MS media. Although seedling contamination with the artificial soil media could not be observed with bare eyes, cotyledon explants harvested from the plants grown on the media showed some fungal growth when they were placed onto MS media for further culture. However the percentage of the contamination from these explants was dramatically decreased by 15 minutes sterilization with 1% NaOCl.

      • KCI등재

        2차원 방사선 규격사진에서 하악골 상행지 고경의 보정분석에 관한 3차원 CT 영상 연구

        황현식,김형민,이기헌,임회정 대한치과교정학회 2007 대한치과교정학회지 Vol.37 No.5

        안면비대칭 환자의 진단 및 치료계획 수립 시 하악골 상행지 고경의 좌우 차이를 정확히 판정하는 것이 필요하다. 본 연구는 2차원 방사선사진에서 정면 상행지경사도 및 측면 상행지경사도를 이용하여 하악골 상행지 고경을 보정하는 방법이 비대칭 판정에 도움이 되는지 알아보고자 시행되었다. 이부 편위가 있는 안면비대칭자 40명을 대상으로 정모두부방사선규격사진을 촬영하고 좌우 각각의 하악골 상행지 고경을 측정하는 한편 정모 및 측모 방사선사진에서 계측된 정면 상행지 경사도 및 측면 상행지 경사도를 이용하여 상행지 고경을 3차원적 개념으로 보정한 후, 실제 3차원 영상에서의 비대칭 판정 결과와 비교 분석을 시행하였다. 측정결과, 정면 및 측면 상행지 경사도는 이부편위측에 비하여 반대측에서 크게 나타났으며 보정 후 상행지 고경의 좌우 차이는 증가하는 양상을 나타내었다. 보정 전 그리고 보정 후 각각에서 상행지 고경의 좌우비대칭 여부를 판정한 후, 3차원 영상에서의 판정을 기준으로 하여 보정에 따른 sensitivity, specificity 그리고 accuracy 변화를 살펴본 결과, specificity는 44%에서 22%로 감소하였으나 sensitivity는 74%에서 94%로 증가하는 것으로 나타났다. 아울러 accuracy가 보정 전 68%에서 보정 후 78%로 증가하는 것으로 나타나 정면 및 측면 상행지 경사도를 이용하여 상행지 고경을 3차원적 개념으로 보정할 경우, 이는 보다 정확한 비대칭 판정에 유용함을 보여주었다. Objective: Defining right and left side differences in mandibular ramus height is one of the key elements in the diagnosis of facial asymmetry. The purpose of the present study was to evaluate the effect of correction of ramus height with frontal and lateral ramal inclinations (FRI and LRI) in 2-dimensional cephalograms and observe how this affects the diagnostic accuracy of asymmetry. Methods: Frontal and lateral cephalograms were obtained in 40 individuals with chin deviation. FRI and LRI were measured on each side and ramus height measurement was corrected with these inclinations using Pythagorean's theorem. The results of diagnosis before and after correction on cephalograms were compared with the results in 3D CT images. Results: Both FRI and LRI showed greater values in the contralateral side than in the chin-deviated side and these contributed to an increase in the right and left side ramus height differences. After comparison of diagnostic results before and after correction on cephalograms with the results on 3D CT images, the sensitivity increased significantly (from 74 to 94 %) whereas the specificity decreased (from 44 to 22 %). Overall accuracy increased from 68 to 78% with the correction using FRI and LRI. Conclusions: The results of the present study indicate that correction of ramus height with FRI and LRI is useful for an accurate diagnosis of facial asymmetry on frontal cephalograms.

      • KCI등재후보

        중층 구조의 경계 완화를 통한 의미 탐색 : 『장군의 수염』의 서술 구조 연구 Study on the Narrative Structure of 'The Beard of A General'

        황정현 현대문학이론학회 2003 現代文學理論硏究 Vol.0 No.20

        This paper has an intention to explain the meaning of The Beard of A General in the dimension of formal aesthetics through the examination of the narrative structure of this novel. This novel has a dual structure composed of an extradiegetic and an intradiegetic and different narrators appear in each narrative level. The two different bodies of narration in the two different narrative levels are closely related with each other through the intervention of the narrators, and this close relationship between the two different bodies of narrationcreates the meaning of the novel in mesh with the narrative. This paper makes an analysis of The Beard of A General focusing on the role of the narrators and the intersection of the two different narrative levels. The beard of A General has a dual structure that presents the process of searching. Both the extradiegetic and the intradiegetic present the process of searching while raising the question of tis own respectively. While both the subject and the object of the search are relatively clear in the extradiegetic, those in the intradiegetic are not. As the narrative progress, the process of searching in the intradiegetic takes on a phase different from that in the extradiegetic. The process of searching in the intradiegetic is characterized by the procedure in which the revelation of a fact gives rise to a question about the past of a character, and the bringing-up of another event creates and additional question rather than help solving the existing question. With the insertion of a mirror text, the two processes of searching finally meet at an intersection where the union of the two meanings in the dual structure can be completed. The mirror text is no other than a novel written by a protagonist. As apart of the intradiegetic, the plot and ending of the mirror text seems to suggest somewhat plausible key to the question raised in the extradiegetic. The mirror text, however, reserves a clear ending of the story and, furthermore, brings up an additional question in a sense that the narrative of the story does not correspond to the truth of the protagonist' life. In The Beard of A General, anther strategy that contributes to the creation of an additional question as well as the searching for an answer to the existing question is the metalepsis that is accomplished between the different narrative levels by the intervention of the narrator. In The Beard of A General, the narratornot only introduces a particular event but also keeps track of the event and, in the end, actively expresses his own idea. In this process, the metalepsis between the different narrative levels occurs, In That is to say, the narrator of the extradiegetic intervenes in the narration of the intradiegetic and, as a result, the border between the narrative levels becomes blurred. On conclusion, the intervention of the narrator and the metalepsis between the different narrative levels contributes to the creation of the overallmeaning of the novel by engaging the extradiegetic with the intradiegetic. The unique formal aesthetics of The Beard of A General effectively contributes not only to searching for an answer to the question that is central to the narrative in the novel, but also to deepening and widening the question itself. In this sense, The Beard of A Generalcan be analyzed as the text in which the meaning of the narrative is created by the structure of the narrative.

      • KCI등재

        안면비대칭자의 하악골 악교정수술 후 정면 연조직 변화 예측을 위한 연구

        황현식,Lee, Jessica J.,황정현,최학희,임회정 대한치과교정학회 2008 대한치과교정학회지 Vol.38 No.4

        본 연구는 안면비대칭 환자의 악교정수술 시 경조직 이동에 따른 연조직 변화를 정면에서 평가함으로써 정면 얼굴 이미지 시뮬레이션 프로그램 개발에 도움이 되고자 시행되었다. 안면비대칭이 동반된 하악골 수술 예정 환자 45명을 대상으로 정모 두부방사선규격사진과 얼굴사진(photo)을 술전 및 술후에 각각 같은 각도로 촬영한 후, 술전 및 술후의 방사선사진을 이용하여 경조직 계측점의 변화를, 얼굴사진을 이용하여 연조직 계측점의 변화를 수평 및 수직으로 구분하여 각각 측정한 후 경조직 변화에 따른 연조직 변화를 비교 분석하였다. 연조직 변화와 경조직 변화의 상관성을 살펴본 결과 수평 방향, 수직 방향 모두에서 전반적으로 낮은 상관성을 보였으며, 1:1 mean ratio 산출을 위하여 서로 상관성이 가장 높은 경조직 계측점을 연조직 계측점별로 선택한 결과 직하방에 있는 경조직보다는 다소 멀리 떨어져 있는 경조직 계측점이 선택되는 경우가 많이 나타났다. 경조직 변화를 이용하여 연조직 변화를 예측할 수 있는 회귀방정식을 연조직 계측점별로 산출한 결과 연조직 수평변화 예측에 경조직 수직변화도 사용되고 연조직 수직변화 예측에 경조직 수평변화도 사용되었으며, 수평과 수직변화 모두에서 가장 설명력이 높은 방정식은 연조직 menton에서 나타났다. 이상의 연구결과 하부 경조직 계측점과 상부 연조직 계측점의 비율을 이용하는 1:1 mean ratio방법은 불가능한 것으로 나타난 반면 회귀분석을 이용한 연조직 변화 예측은 임상에 도움이 될 수 있는 것으로 나타나 정면 이미지의 경우 컴퓨터를 이용한 시뮬레이션 프로그램이 반드시 필요함을 시사하였다. Objective: To aid the development of a frontal image simulating program, we evaluated the soft tissue frontal changes in relationship to movement of hard tissue with orthognathic surgery of facial asymmetry patients. Methods: Preoperative and postoperative frontal cephalograms and frontal view photographs of 45 mandibular surgery patients with facial asymmetry were obtained in a standardized manner. Vertical and horizontal changes of hard tissue and soft tissue were measured from cephalograms and photographs, respectively. Soft tissue change in result to hard tissue change was then analyzed. Results: Both vertical and horizontal correlation analysis showed a weak relationship between the changes. Hard tissue points that were picked for 1:1 mean ratio with soft tissue points did not show any significant relevance. For each soft tissue change, regressive equation was formulated by stepwise multiple regression analysis, and the equation for soft tissue Menton was most reliable in predicting changes. Both vertical and horizontal hard tissue changes were used together in prediction of vertical or horizontal soft tissue change. Conclusions: The results suggest that computerized image simulation using regression analysis may be of help for prediction of soft tissue change, while 1:1 mean ratio method is not useful.

      • KCI등재후보

        백서에서 치아이동 후 보정기간 동안 교합이 치주조직섬유의 재형성에 미치는 영향

        정권희,박영준,이기헌,황현식 대한치과교정학회 2003 대한치과교정학회지 Vol.33 No.2

        본 연구는 실험적 치아이동 후 보정기간 동안 교합이 치주조직섬유의 물리적 강도에 미치는 영향을 알아보고자 시행되었다. 체중 200g 내외의 Sprague-Dawley계 백서 수컷에서 상악 양측 제1대구치와 2대구치 사이에 교정용 고무줄을 삽입하여 4일 동안 치아를 이동시킨 다음, 각 실험동물의 하악 좌측 베1, 2, 3대구치를 발치하여 우측은 대합치가 있는 교합측으로, 좌측은 비교합측으로 구분하였다. 상악 제1대구치와 2대구치 사이의 인접면에 유지구를 형성하고 광중합형 레진으로 채워 보정을 시행한 후 시작 0일, 4일, 8일, 12일, 16일 또는 20일 경과한 후 백서를 희생시킨 다음, 만능물성 시험기를 이용하여 상악 제1대구치를 발치할 때 필요한 최대인장강도를 측정 좌우간 비교 분석하여 다음과 같은 결과를 얻었다. 1. 교합측은 비보정군에서 보정 4일, 8일, 12일, 16일, 20일군으로 갈수록 최대인장강도사 증가하였고, 보정 12일군 이후부터 통계적으로 유의한 차이를 보였다(p<0.05). 2. 비교합측은 비보정군에서 4일, 8일, 12일, 16일, 20일군으로 갈수록 최대인장강도가 증가하는 경향을 보였으나 통계적으로 유의한 차이를 보이지 않았다(p<0.05) 3. 교합측과 비교합측의 최대인장강도를 비교한 결과 보정 8일군까지 통계적으로 유의한 차이를 보이지 않았으나 (p>0.05), 보정 12일군 이후 보정 20일군까지 통계적으로 유의한 차이를 보였다(p<0.05). 이상의 결과는 실험적 치아이동 후 보정기간 동안 교합이 치주조직 섬유의 재형성에 영향을 미침으로 보정장치의 선택, 기간설정 등 보정계획서 교합에 대한 고려가 필요함을 시사하였다. The purpose of this study was to valuate the effect of occlusion on the mechanical strength of periodontal fibers during retention periods after experimental tooth movement. In the Sprague-Dawley male rats weighing 200g or more, the intraoral elastics were inserted into the both right and left interproximal space between upper first and second molars for tooth movement. After 4 days later, the left lower first, second, and third molars were extracted for differentiating the non-occlusal side from the occlusal side in the same mouth. At the same time the elastics were removes and than light cured resin was placed in the space between upper first and second molard following undercut was made for retention bilaterally. From the beginning of retention, 7 rats were sacrificed at 0, 4, 8, 12, 16, 20 days respectively. For evaluating of magnitude on the mechanical strength of periodontal tissue, the maximal shear load of the upper first molars were measured bilaterally during extraction using Instron Universal Testing Machine. The results of this study were obtained as follows : 1. In the occlusal side, the maximal shear load was increased from no retention to retention 20 days group as time was going and statistically difference was shown from retention 12 days group (p<0.05). 2. In the non-occlusal side, the maximal shear load was increased slightly from no retention 20 days group as time was going but there was no statistically difference (p>0.05) 3. The result compared with the maximal shear load between occlusal and nonocclusal side showed no statistically difference until retention 8 day group (p>0.05), but showed statistically difference from retention 12 day to 20 day group (p<0.05). These results show that occlusion had an effect on mechanical strength of the periodontal fibers during retention periods after experimental tooth movement; therefore, it is suggested that occlusion should be considered while the retainer types and retention period are planned.

      • 전기도금을 이용한 스테인레스스틸 각형 선재의 굵기 증가 후 물성 변화

        이정석,황현식,최광철,문재동 전남대학교 치의학연구소 2002 구강과학 Vol.14 No.1

        The purpose of this study was to evaluate clinical applications of electroplating method through investigation of the physical properties of orthodontic rectangular wires according to varying their cross section. For the study, it was accomplished to electroplate the 0.016-inched orthodontic rectangular stainless steel wire. The cross section of stainless steel orthodontic rectangular wire increased from 0.016 X 0.016 inch to 0.017 X 0.017 inch by electroplating. The wire was heat treated to improve an adhesion between the wire and electroplated metal. A three-point bending test and torsion test were conduced in order to compare physical properties among three wire groups; 0.016 X 0.016 wires(group 016P) and 0.017 X 0.017 wires(group 017). Through the investigations of each wire group, following results were obtained. 1. At three-point bending test, the group 016P showed higher tendency in the degree of stiffness, yield strength and ultimate tensile strength than the group 016. Stiffness and ultimate tensile strength showed statistically significant differences between two groups at three-point bending test(p<0.05). 2. Stiffness, yield strength, and ultimate tensile strength of the group 016P showed lower tendency than those of the group 017. Stiffness showed statistically significant differences between two groups at three-point bending test(p<0.05). 3. Torque/twist rate, yield torsional moment, and ultimate torsional moment of the group 016P showed higher tendency than those of the group 016. All measurements showed statistically significant differences between two groups after torsion test(p<0.05). 4. Torque/twist rate, yield torsional moment, and ultimate torsional moment of the group 016P showed lower tendency than those of the group 017. Yield torsional moment, and ultimate torsional moment showed statistically significant differences between two groups after torsion test(p<0.05). Xylitol is a 5-carbons carbohydrate, which can be replaced with sucrose for preventing caries. The replication of Streptococcus mutans and its formation of artificial plaque were studied in the media containing xylitol. The combined effect of xylitol and other carbohydrates on Streptococcus mutans was also studied. The replication of Streptococcus mutans was inhibited according to the increased concentration of xylitol. Streptococcus mutans replicated at the initial stage of incubation in the media contaning glucose, fructose or lactose, while replication from the beginning of incubation in the media containing fructose as combining with xylitol. The formation of artificial plaque by Streptococcus mutans was significantly reduced in the media containing with xylitol and fructose. These results indicated that the replication of Streptococcus mutans was inhibited according to the increased concentration of xylitol, and the formation of artificial plaque by Streptococcus mutans was significantly inhibited in the media containing xylitol and fructose.

      • KCI등재

        안면비대칭 진단을 위한 하악골 3차원영상 계측기준치에 관한 연구

        안정순,이기헌,황현식 대한치과교정학회 2005 대한치과교정학회지 Vol.35 No.2

        기존의 2차원적 진단자료는 상의 확대 및 왜곡으로 인해 형태나 크기의 정량적 평가시부적절한 결과를 야기할 수 있어 안면비대칭의 정확한 진단과 치료계획 수립을 위해서는 3차원영상 진단의 도입이 필요하다. 본 연구는 안면비대칭 진단시 3차원적 분석에 도움이 되는 기준자료를 얻고자 정상교합자를 대상으로 하악골 3차원영상 계측항목의 평균값과 좌우차이의 정상범주를 알아보기 위하여 시행되었다. 뚜렷한 안면비대칭을 보이지 않는 성인 정상교합자 남녀 30명씩 총60명을 대상으로 두경부 전단화단층사진을 촬영한 후 컴퓨터 프로그램을 이용한 각각의 단면 촬영영상 정보를 이용하여 3차원 입체영상을 재구성한 다음, 하약골 비대칭시 좌우차이를 보일 수있는 계층항목 ramus length를 나타내는 6개 condyla neck length를 나타내는 1개, mandibular body length를 나타내는 8개 등 15개의 거리 계층항목과 gonial angle을 나타내는 4개, frontal ramal inclination을 나타내는 2개, lateral ramal inclination을 나타내는 2개 등 8개의 각도계층항목. 총 23개의 계층항목을 설정한 후, 좌측과 우측을 구분하여 컴퓨터 상에서 3차원계측치를 구하고 좌우차이값을 산출하였다. 본 연구결과 얻어진 정상교합자의 하악골 3차원영상 계층항목의 좌우차이값은 안면비대칭 환자의 진단 기준치로 유용하게 사용될 수 있을 것이다. For an accurate dlagnosis and treatment planning of facial asymmetry, the use of 3-dimensional(3-D) image is indispensable. The purpose of this study was to get standard data for the 3-D analysis of facial asymmetry.Computerized tomography(CT) was taken in the 60 normal occlusion individuals (30 male, 30 female) who did not have any apparent facial asymmetry. The acquired 2D CT DICOM data were input on a computer, and the reformatted 3-D images were created using a 3-Dimage software. Twenty three measurements were established in order to evaluate asymmetry:15linear measurements (6 for ramus length, 1 for condylar neck length, and 8 for mandibular body length) and 8 angular measurements (4 for gonial angle, 2 for frontal ramal inclination, and 2 for lateral ramal inclination). The right and left difference of each measurement was calculated and analyzed. Itis suggested that the right and left differences of the measurements obtained from the study could be used as references for the diagnosis of facial asymmetric patients.

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