• 대한치과기공학회지
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• 제38권1호
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• pp.51-61
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• 2016

Purpose: This study was conducted to find oral health and eating attributes relating to the maxillary anterior teeth color and examine the meaning. Methods: This study aims to prepare the basic data of the teeth color by measuring analyze mode using the color of the maxillary anterior teeth(maxillary central incisor, lateral incisor, canine) of the dental patients as the dental colorimeter. Also, This researcher explained the purpose of this study to dental patients and got agreement of 111 patients(50 men and 61 women). We conducted the survey from 2 March to 25 May, 2015. So the color of total 333 teeth was examined, and eating habit attributes and oral health behaviors were researched. Results: Lightness(L) was significantly high in female compared to male(12, p<0.05), the more often intake of red pepper paste decreased(11, 13) lightness. and the brightness of the 31-40 age group was significantly higher(12, p<0.05) than the group under the age of 20. Red chroma(a) was significantly low in over 50 age group compared to the group under the age of 20(12, p<0.05), and the red chroma(a) of the "received periodic scaling" group was significantly lower(13, p<0.01) than the other group.

• Imaging Science in Dentistry
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• 제44권1호
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• pp.43-52
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• 2014

Purpose: This study was designed to evaluate whether magnetic resonance imaging (MRI) is appropriate for detecting early changes in the mandibular bone marrow and pulp tissue of rats after high-dose irradiation. Materials and Methods: The right mandibles of Sprague-Dawley rats were irradiated with 10 Gy (Group 1, n=5) and 20 Gy (Group 2, n=5). Five non-irradiated animals were used as controls. The MR images of rat mandibles were obtained before irradiation and once a week until week 4 after irradiation. From the MR images, the signal intensity (SI) of the mandibular bone marrow and pulp tissue of the incisor was interpreted. The MR images were compared with the histopathologic findings. Results: The SI of the mandibular bone marrow had decreased on T2-weighted MR images. There was little difference between Groups 1 and 2. The SI of the irradiated groups appeared to be lower than that of the control group. The histopathologic findings showed that the trabecular bone in the irradiated group had increased. The SI of the irradiated pulp tissue had decreased on T2-weighted MR images. However, the SI of the MR images in Group 2 was high in the atrophic pulp of the incisor apex at week 2 after irradiation. Conclusion: These patterns seen on MRI in rat bone marrow and pulp tissue were consistent with histopathologic findings. They may be useful to assess radiogenic sclerotic changes in rat mandibular bone marrow.

• 대한치과교정학회지
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• 제26권2호
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• pp.197-204
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• 1996

이 연구는 악안면 영역의 심미적 개선에 필요한 미소의 형태에 대한 기준을 설정하기 위하여 시행하였다. 성인 정상교합자 62명(남자;30명, 평균연령;22.7세, 여자;32명, 평균연령;21.8세)을 대상으로 안정위시와 미소시의 얼굴 정면 사진을 촬영하였고, 미소시 입술의 형태변화, 그리고 입술과 치아와의 관계를 계측, 분석하였다. 이 연구로 부터 얻어진 결과는 다음과 같다. 1. 하순 상연의 만곡과 상악 절단연과의 평행관계인 smile line ratio는 0.09이었고, buccal corridor ratio는 0.63, smile symmetry ratio는 0.96이었다. 2. 미소시 양 구각주 간의 거리는 안정위시 구각부 간 거리의 1.31배였으며, 얼굴 폭의 0.48배였다. 3. 미소시 상순의 수직길이는 안정위시 길이의 0.69배였고, 하순의 수직길이는 안저위시 길이의 0.96배였다. 4. 상악 전치의 노출량은 9.96mm이었고, 상악 전치의 노출은 미소시 상순의 수직길이의 변화율이 었고, 미소시 구각부 길이의 비, buccal corridor ratio등과 관계 깊었다.

• Journal of Periodontal and Implant Science
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• 제36권4호
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• pp.817-827
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• 2006

Purpose : This study was designed 1) to compare the perception of dental professionals and lay people with respect to minor variations in maxillary anterior tooth size and alignment and their relation to the surrounding soft tissues, and 2) to evaluate the normal tooth-gingiva topographical relationships in periodontally healthy young subjects, Materials and methods : Maxillary anterior teeth were intentionally diagrammed in varying degree of deviation with respect to one of three common anterior esthetic discrepancies including variations in crown length, shape of gingival margin, and length of interproximal contact, 17 images were generated to be preferentially selected by 2 groups consisting of dental professionals and lay people (total of 740). Smiling photographs of 120 dental students who had healthy periodontium were taken and the photographic images were analyzed to be classified as 17 kinds of altered image groups. Results : The results demonstrated noticeable difference between the varying levels of discrepancy. Both group preferred gingival margin of lateral incisor to be 0.5mm lower than that of central incisor. Lay people preferred the gingival margin shape that has 2/9 horizontal component of the crown width, while dental professionals preferred the gingival margin shape that has 1/9 horizontal component of the crown width. Lay people preferred longer length of the interproximal contact (two thirds of the crown length), whereas dental professionals preferred shorter length of the interproximal contact (half of the crown length). Photographic analysis of normal esthetic gingival topography revealed 2/9 horizontal component and short length of the interproximal contact which was of the hybrid nature of the preferences shared by lay people and dental professionals. Conclusion: The results of this study show that dental professionals and lay people demonstrated significant difference in their preference of dental esthetic components, which may then influence the decision making process by dental professionals with respect to designing the anterior esthetic gingival line.

• 치위생과학회지
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• 제11권3호
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• pp.251-255
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• 2011

이에 본 연구에서는 치근흡수의 경향을 평가하기 위하여 교정치료 기간, 성인과 청소년, 성별, 발치와 비발치 등으로 분류 하였으며, 서울 경기 소재의 3개 교정 전문치과 병의원에서 140명을 교정치료 6개월 전과 교정치료 완료 후 6개월 이내에 촬영된 치근단 방사선 사진에서 상 하악 6전치의 치근흡수를 치아별로 평가 비교하여 다음과 같은 결론을 얻었다. 1. 교정치료 기간에서 성인군은 24.7개월이고 청소년군은 33.5개월로 성인군과 청소년군 간에는 유의한 차이가 있었다(p<0.05). 2. 성인 환자는 청소년 환자에 비해 치근 흡수도에 유의한 차이를 보였다(p<0.05). 3. 여자 환자에서 전반적으로 높은 치근 흡수도를 보였으나 유의한 차이가 없었다(p>0.05). 4. 발치가 비발치 환자보다 높은 치근 흡수도를 보였으나 유의한 차이가 없었다(p>0.05). 5. 상악 중절치와 측절치에서는 발치군이 비발치군에 비해 통계적으로 높은 치근 흡수도가 나타났다(<0.05). 이상의 결과로 볼 때, 성인 환자에서 치근 흡수가 많이 나타나고, 특히 상악 중절치, 측절치에서 치근흡수가 나타나므로 교정 치료시 주의가 필요하며 더 많은 연구가 이뤄져야 할 것으로 사료된다.

• 대한치과보철학회지
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• 제29권3호
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• pp.141-170
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• 1991

This study was to analyze the displacement and the magnitude and mode of distribution of the stresses in the lower overdenture, the mucous membrane, the abutment teeth and the mandibular supporting bone when various abutment designs were subjected to different loading schemes. For this study, the two-dimensional finite element method was used. The models of overdenture and mandibe with the canine and the second premolar remaining, were fabricated. In the first design, a 1 mm space was prepared between the denture and the dome abutment with the height of 2 mm(OS). In the second design, a contact between the denture and the occlusal third of the dome abutment with the hight of 2 mm was prepared(OC). In the third design, a 0.5 mm space was prepared between the denture and 8 degree tapered cylindrical abutments with the height of 7 mm(TS). In the fourth design, a contact between the denture and the occlusal two thirds of the conical abutments with the height of 7 mm was prepared(TC). In order to represent the same physiological condition as the fixed areas of the mandible under loading schemes, the eight nodes which lie at the mandibular angle, the coronoid process and the mandibular condyle were assumed to be fixed. Each model was loaded with a magnitude of 10 Kgs on the first molar region (P1) and 7 Kgs on the central incisor region (P2) in a vertical direction. The force of 10 Kgs was then applied distributively from the first premolar to the second molar of each motel in a vertical direction (P3). The results were as follows: 1. The vertical load on the central incisor region(P2) produced the higher displacement and stress concentration than that on the posterior region(P1, P3). 2. The case of space between abutment and denture base produced higher displacement than that of contact, and the case of long abutment produced higher displacement than that of short abutment because of low rigidity of denture base. 3. The magnitude of the torque and vertical force to the abutment teeth and the stress distribution to the denture base was higher in the telescope coping than in the overdenture coping. 4. The vertical load on the central incisor region(P2) produced higher equivalent stress in the mandible than that on the posterior region(P1, P3). 5. The case of space between abutment and denture base produced better stress distribution to the farther abutment from the loading point than that of contact. 6. In case of sound abutment teeth, the type of telescope coping can be used, hilt in case of weak abutment, the type of overdenture coping is considered to be favorable generally.

• 대한소아치과학회지
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• 제37권4호
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• pp.488-496
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• 2010

치외치는 교합면에 법랑질이 원추형으로 돌출되어 결절을 형성한 치아로서, 치아발육 중 법랑기의 내측법랑상피가 외부로 과증식되거나 치수 간엽조직이 국소적으로 과증식되어 나타난다. 교합력이나 저작에 의해 파절 또는 마모되기 쉬우며 따라서 이로 인하여 치수노출에 의한 감염이 야기될 수 있다. 상악 전치부 설면에도 원추형으로 돌출된 결절이 관찰되기도 하는데 이를 탈론 교두(talon cusp)라 한다. 치내치는 치아 발육 중 설측의 법랑상피가 일부 함입되어 설측에 깊은 소와가 형성된 형태로서 크기나 전체적인 모양은 정상이다. 방사선 사진상에서 치경부의 법랑질 일부가 함입되어 함입강을 형성하고 그 기저부는 치수에 가까이 위치하고 있어 치수와 개통되어 있을 가능성도 있다. 탈론 교두(talon cusp)와 치내치는 비교적 흔한 형태 이상이지만, 한 치아에 동시에 발생하는 경우는 매우 드물다. 이러한 환자에서 탈론 교두(talon cusp)가 교합력이나 저작에 의해 파절되거나, 교두 사이 열구가 우식에 이환되어 치수치료가 시행 될 때, 치내치의 복잡한 근관 형태로 인해 많은 어려움이 있다. 따라서 교합조정, 치면열구전색술 등의 예방적 처치와 주기적인 검진이 필요하고, 치수치료시 정확한 방사선학적 진단을 통한 치내치의 근관 형태 파악이 필요하다. 조선대학교 치과병원 소아치과에 내원한 10세 남아(하악 좌측 중절치)와 8세 여아(상악 우측 중절치) 그리고 7세 남아(상악 우측 중절치)에서 치내치를 동반한 탈론 교두(talon cusp)가 관찰되어 본 증례를 보고하고자 한다. 9세 남아와 8세 여아는 치수 병변으로 인해 치수 치료 중이고, 7세 남아는 병적 소견 없이 교합조정 후 관찰 중이다.

• 대한소아치과학회지
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• 제36권4호
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• pp.580-585
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• 2009

소아치과 영역에서 치아수의 이상은 흔히 관찰할 수 있으며, 그 중 대표적인 것의 하나가 과잉치이다. 과잉치의 발생원인에 대해서는 여러가지 가설이 있으며 유전적 또는 환경적 요인에 의해 치배 형성기의 정상 치판이 과도하게 증식하여 발생되는 것으로 알려져 있다. 과잉치가 가장 흔하게 발생되는 부위는 상악에서는 절치부로 그 빈도는 80-94% 정도로 보고되고 있고 그 다음으로는 구치부와 소구치부 순서로 나타난다. 상악에 비해 하악에서는 대부분 소구치 부위에서 발생되며 절치부에서는 전체 과잉치 발생빈도 중 단지 1-2% 이하로 매우 낮은 빈도로 발생되는 것으로 보고되고 있다. 이 증례는 드물게 나타나는 하악 절치부에 2개의 과잉치가 있다는 주소로 내원한 만 6세 남아에서, 임상 및 방사선학적 검사 결과 하악 절치부에 정상치와 크기와 형태가 비슷한 정상치형의 과잉치 2개를 포함하여 6개의 절치가 존재하는 것이 관찰되었다. 발치할 치아의 정확한 진단 및 결정을 위해 컴퓨터 단층 촬영을 시행하였고 발치 후 하악 전치부의 정상적인 배열을 위해 치아 맹출에 대한 주기적 정기 검진 후 교정적 평가와 치료를 진행할 예정이다.

• 대한치과교정학회지
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• 제15권2호
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• pp.229-237
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• 1985

The Purpose of this study was to investigate the differences in soft tissue characteristics according to the dental or skeletal dysplasia. For this purpose, lateral cephalogram of 153 children (Hellman dental age IIIB: control group 32, Angle CIII. div. 1 malocclusion group 55, Angle Cl III group 66) were traced and measured. For these measurements, following conclusions were made. 1. FH A, FH Sn, FH UL, AA' of the Class III group were thicker than those of the normal and Class II group, but FH B, FH LL, BB' of the Class III group were not significantly different from those of the normal group. 2. FH B, FH LL, BB' of the Class II group were thicker than those of the normal and Class III group, but FH A, FH Sn, FH UL, AA' of the Class II group were not significantly different from those of the noraml group. 3. Ans-Sn, FH P were not significantly different in three groups, while PP' of the Class III group was thicker than those of the other groups. 4. The lower lips of the Class II group were more anterioly everted with respect to the lower incisor inclination than those of the other groups. 5. The severity of skeletal dysplasia was partly camouflaged by the soft tissue.

• 대한치과교정학회지
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• 제9권1호
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• pp.15-22
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• 1979

This study was undertaken to establish the cephalometric standard of Hellman dental age IVA group of Korean. The subjects consisted of 40 males and 44 females with normal occlusion and aceptable profile. The results were obtained. 1) The tables of standard deviation from the measurements were made. 2) All linear measurement was greater in male than in female. 3) Female had more convex profile than male, 4) Facial convexity, upper and lower lip of esthetic line were gradually decreased with. age. 5) Upper incisor was gradually labioversioned with age.