• 대한치과교정학회지
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• 제41권3호
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• pp.184-190
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• 2011

하악 절치부에서 보이는 총생은 하악 절치의 큰 MD/FL (mesiodistal/faciolingual) 인덱스와 관련이 있음이 보고되었다. 큰 MD/FL 인덱스를 보이는 절치에서 치간 삭제를 통해 근원심폭경을 줄여 MD/FL 인덱스를 줄이고 공간을 확보하는 방법이 정당화되기 위해서는 MD/FL 인덱스가 클수록 인접면 법랑질 두께가 더 두꺼워야 할 것이다. 본 연구의 목적은 하악 절치의 MD/FL 인덱스, 근원심폭경, 최대풍융부/치경부폭경비와 같은 치아의 형태적 요인과 인접면 법랑질 두께 사이에 상관관계가 있는지를 조사하는 것이었다. 발거된 하악 절치 40개에서 MD/FL 인덱스, 근원심폭경, 최대풍융부/치경부폭경비를 구하였으며, 근원심폭경을 구한 선상까지 순면을 연마하여 그 단면에서 법랑질 두께를 측정하였다. 치경부근원심폭경은 순면을 연마한 단면에서의 좌우측 백악법랑경계 사이의 폭경을 측정하였다. 이후 법랑질 두께와 MD/FL 인덱스, 근원심폭경, 최대풍융부/치경부폭경비의 상관관계를 조사하였다. 연구결과 하악 절치의 법랑질 두께는 편측에서 $0.75{\pm}0.07mm$였고, 근원심폭경은 $5.56{\pm}0.40mm$였다. 법랑질 두께와 근원심폭경 간에는 유의한 상관관계가 있었지만(R = 0.68), 법랑질 두께와 MD/FL 인덱스, 법랑질 두께와 최대풍융부/치경부폭경비 간에는 상관관계가 없었다. 이는 근원심폭경이 큰 치아에서는 치간 삭제를 더 많이 할 수 있지만, 동일한 근원심폭경을 갖는 절치들의 경우 MD/FL 인덱스가 큰 하악 절치 또는 최대풍융부/치경부폭경비가 커서 삼각형의 형태를 갖는 하악절치에서 치간 삭제를 더 많이 할 수는 없다는 것을 나타낸다.

• Journal of Plant Biology
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• 제37권2호
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• pp.203-221
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• 1994

한국산 나자식물 5과 12속 19분류군을 대상으로 광학현미경, 주사전자현미경 및 투과전자현미경을 이용하여 화분의 형태를 비교 관찰하고 기재하였으며, 각 과별 검색표를 작성하였다. 분류학적으로 볼 때 취급된 나자식물의 화분립은 모양, 크기, 표면상태, 표면무늬, 기낭의 유무 및 돌기의 유무에 의해 뚜렷이 구분되어 속간 및 속 이하의 분류군에는 유용하였으나, Pinus속내의 종들은 본 연구에서 관찰된 화분립의 크기나 표면무늬에 의해서는 화분형질의 중복으로 인해 종분류는 유용하지 않은 것으로 밝혀졌다. 소나무과내의 Picea속에 속하는 P. koraiensis의 화분립은 기낭의 형태가 불규칙하고, 몸체에 비해 기낭의 크기가 크며, 표벽이 얇기 때문에 기낭을 갖는 Pinus속과 Abies속의 분류군과는 차이점이 뚜렷하다. 또한 Abies속의 특징으로 기재된 모부의 중앙부위에서 기낭쪽으로 갈수록 표벽이 얇아진다는 점, 화분림 몸체의 표면이 비교적 굴곡이 심하지 않다는 점과 화분립의 크기가 크다는 점으로 볼 때 P. koraiensis는 기낭을 갖는 Pinus속과 Abies속 중 Abies속과 화분학적으로 유연관계가 가까운 것으로 추정된다. 투과전자현미경관찰을 통해 기낭을 갖는 화분립을 조사한 결과 근극에는 내표벽과 외표벽이 모두 존재하나, 서로 분리되어 외표벽은 기낭과 연결되고 내표벽은 원극을 이룬다. 또한 구과목의 분류군들에 있어 소나무과를 제외한 주목과, 난우송과 및 측백나무와 일부 분류군의 내표벽이 여러 층으로 구성된 관상구조로 나타났다. 주사전자현미경으로 기낭을 관찰한 결과 표면무늬는 유공상이고 미세한 pit가 존재하는 것으로 관찰되었다. 기낭의 표면무늬는 광학현미경상에서 망상으로 보이나 투과전자현미경으로 관찰해 본 결과 이는 기낭내부의 망상구조가 광학현미경하에서 투시된 것으로 밝혀졌다.

• Advances in pediatric surgery
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• 제4권2호
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• pp.93-99
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• 1998

Anal endosonography has recently been popularized in adult patients in order to access staging of rectal cancer and other lesions of the anorectum. This study is not familiar to pediatric surgeons. We performed anal endosonography in 30 children without anorectal disease in order to determine the standard morphology of the anorectum. The internal anal sphincter(IAS) was clearly identified as a homogeneous hypoechoic circular band, extending caudally to a level just proximal to the anal verge. The external anal sphincter(EAS) showed mixed echogenicity and different architecture along the anal canal; the EAS was U-shape in the upper canal and it had a circular pattern in the lower canal. In the upper canal of girls, the perineal body and the vagina were found just anterior of the anal canal, which made the U shape of the EAS. In the male, the sphincter tapered anteriorly into two arcs that met in the midline. The perineal body was prominent in the female. Posteriorly, the anococcygeal ligament was represented by a triangular shadow in both sex. The thickness of the IAS was measured in 3 directions, left, right and posterior, at 3 levels, upper, middle and lower areas of the anal canal. The average thickness was 0.86-2.40 mm between 6 and 18 months of age(Group 1), 0.88-3.20 mm between 19 and 36(Group 2), 1.07-2.20 mm between 37 and 54(Group 3) and 1.18-2.42 mm more than 54-month-old(Group 4). The thickness was correlated with the age of the children only in the right upper(p=0.008) and the left middle portion(p=0.015). We were able to obtain standard morphologic features of the normal anal canal in children with anal endosonography. We believe that this technique is a safe and an effective procedure to evaluate anorectal lesions in children.

• 한국패류학회지
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• 제26권1호
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• pp.33-43
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• 2010

The ultrastructure of germ cells during spermatogenesis and some characteristics of sperm morphology in male Mytilus coruscus, which was collected on the coastal waters of Gyeokpo in western Korea, were investigated by transmission electron microscope observations. The morphology of the spermatozoon has a primitive type and is similar to those of other bivalves in that it contains a short midpiece with five mitochondria surrounding the centrioles. The morphologies of the sperm nucleus type and the acrosome shape of this species have an oval and modified cone shape, respectively. In particular, the axial rod is observed between the nucleus and acrosome of the sperm. The spermatozoon is approximately $45-50{\mu}m$ in length including a sperm nucleus (about $1.46{\mu}m$ in length), an acrosome (about $3.94{\mu}m$ in length) and tail flagellum (approximately $40-45{\mu}m$). The axoneme of the sperm tail flagellum consists of nine pairs of microtubules at the periphery and a pair at the center. The axoneme of the sperm tail shows a 9+2 structure. Some special charateristics of sperm morphology of this species in the genus Mytilus are (1) acrosomal morphology, (2) the number of mitochondria in the midpiece of the sperm, and (3) the existence of a satellite. The axial rod appears in the acrosome and sperm nucleus as one of the characteristics seen in several species of the subclass Pteriomorphia, unlikely the subclass Heterodonta containing axial filament instead of the axial rod. The number of mitochondria in the midpiece of the sperm of this species in the family Mytilidae are five, as one of common characteristics appeared in most species in the family Mytilidae. Most of Mytilus species contain a satellite body which is attached to the proximal centriole in the middle piece of the sperm, as one of common characteristics of sperm morphology in the family Mytilidae.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1995년도 추계학술대회
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• pp.34-38
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• 1995

Using a 3-D finite element method (FEM), the biomechanical characteristics of a threaded truncated acetabular component and a porous coated hemispherical acetabular component were studied. The Von-Mises stress/strain patterns in the acetabulum reconstructed with these two different types of cementless acetabular cups were investigated. The geometry and dimensions of human hemi-pelvis used in the present shape modeling for finite element analysis were scanned with a 3-D laser scanner(TDS-9000, Cyberware, USA). The scanned data was numerically handled with a shape modelling software 'Pro-Engineer'. Using 19836, 16853 tetrahedral elements, respectively, the stress and displacement field of the acetabulum reconstructed with the two different types of the acetabular components were computed. While the hemi-sphere component was found to show a relatively similar stress/strain patterns to those in the normal hip, the results with the threaded cup showed a considerably different patterns from those in the normal condition. Several regions in cancellous bone near the threads and the edge of the truncated cup was found to be overstressed, especially in the superior-lateral part of the acetabulum. It was postulated that the excessive reaming-out of subchondral bone layer when the truncated cup was used can cause the presence of these overstressed regions of cancellous bone. This theoretical prediction for the implanted acetabulum appeared to consistent with the pathological observation of proximal/medial migration of the threaded truncated acetabular prostheses in the previous publications.

• 대한관절경학회:학술대회논문집
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• 대한관절경학회 제21차 추계 학술대회
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• pp.153-153
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• 2009

The purpose of this study was to evaluate tibial tunnel widening prospectively after anterior cruciate ligament (ACL) reconstruction with hamstring tendon grafts using Rigidfix (DePuy Mitek, Raynham, MA) femoral fixation and Intrafix (DePuy Mitek) tibial fixation. 56 consecutive patients who underwent ACL reconstruction with a minimum of 2 years' postoperative evaluation were reviewed. On the anterior-posterior (AP) and lateral radiographs, the diameter of the tibial tunnel was measured at proximal, middle, and distal positions and the shape of the tibial tunnels were classified. Tunnel widening was defined as widening of greater than 2 mm. Group I was defined as cases with no tunnel widening and group II defined as cases with tunnel widening. Postoperative laxity evaluations were performed using Lachman test, pivot-shift test, and Instrumented laxity testing using the KT-1000 arthrometer. On the AP radiographs, the average diameter of the tibial tunnel increased 8.8% at 6 months and 8.5% at 12 months postoperatively compared to the immediate postoperative day. On the lateral radiographs, the average diameter of the tibial tunnel increased 7.2% at 6 months and 8.1% at 12 months year postoperatively compared to the immediate postoperative day. The tunnel shape evaluation revealed predominantly linear type in 53 patients (95%). Group I was 42 patients (75%) and group II was 14 (25%). The average KT-1000 measurement was 1.0~1.8 mm in group I and 2.1~2.8 mm in group II (p>0.05) The Lachman and pivot-shift showed tests no significant differences between the two groups. In conclusion, hamstring ACL reconstruction using Rigidfix and Intrafix fixation showed less widening of the tibial tunnels than observed in previously published studies.

• 대한구순구개열학회지
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• 제4권2호
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• pp.69-78
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• 2001

Alveolar cleft exists in 75% of cleft patients, In alveolar cleft patients, alar base is widening, palatal fistular formation, maxillary growth disturbance & tooth loss of adjacent area is raised, Alveolar bone grafting, especially iliac bone grafting, is a general treatment method. As operation timing, bone grafting is classified with primary, early secondary, secondary, & late secondary, Here we report cleft width, marginal bone height, bone resorption rate, grafted shape & bone densities after secondary iliac bone grafting was done in the Dept. of oral and maxillofacial surgery of chonbuk national university hospital. We compared cleft width to bone resorption rate and grafted shape. Also, alveolar bone densities of grafted and contralateral site was compared with Emago 3 package? (Oral Diagonostic System, The Netherlands), The data obtained were analyzed using Spearman's rho coefficients and sign test with SPSS for window, The results were obtained as follows. 1. As alveolar cleft width is increase, bone resorption rate is, too. This relation showed significant difference(P<.01). 2, In proximal & distal area, alvolar cleft width and bone graft contour after bone grafting had a reverse proportional difference. It was not significant difference(P>.05). 3. After 3 month, in bone density results by using Emago 3 package? with periapical standard view, occlusal view & panoramic view, differences between grafted bone and alveolar bone of contralateral site didn't show a significant difference(P>.05). Thus, differences of bone densities in the alveolar bones didn't exist.

• 대한족부족관절학회지
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• 제18권2호
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• pp.43-47
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• 2014

Hallux valgus is a lateral deviation of the first phalanx and medial deviation of the first metatarsal at the first metatarsophalangeal (MP) joint. Its incidence has increased due to developing footwear. The etiologies include fashion footwear, genetic causes, anatomical abnormality around the foot, rheumatoid arthritis, and neuromuscular disorders. Physiologic alignment of the first MP joint is maintained by congruent and symmetric alignment of the articular surface of the first proximal phalanx and first metatarsal head, physiologic relationship of the distal first metatarsal articular surface and the first metatarsal shaft axis, and stable balance of soft tissue around the first MP joint and stable tarsometatarsal joint. Several factors have been associated with hallux valgus, including pes planus, hypermobility of the first tarsometatarsal joint, flattened shape of the first metatarsal head, increased distal metatarsal articular angle, and deformation of the medial capsular integrity. History and physical examination are very important to diagnosis of hallux valgus. Simple radiography provides information on deformity, particularly in weight-bearing anteroposterior and lateral radiographs. Understanding the etiologies and pathophysiology is very important for success in treatment of patients with hallux valgus.

• 대한의용생체공학회:의공학회지
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• 제14권1호
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• pp.23-30
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• 1993

We investigated the structural geometry of thirty-eight Korean femurs. The purpose of this study is to identify major geometrical differences between Korean femurs and others that we believe belong to Caucasians so that we would be able to get insights into the femoral component design that fits Asians including Koreans. We utilized computerized nomography (CT) images of femurs extracted from cadavers. The CT images were transformed into bitmap data by using a film scanner, and then analyzed by using a commercially available software called Image v.1.0 and a Macintosh loci computer. The resulting data were compared with already published data. The major results show that the geometry of the Korean femurs is significantly different from that of Caucasians: (1) the anteversion angle and the canal (tare Index are greater by the amount of approximately 8" and 0.5, respectively, (2) the shape of the isthmus cross section is more round , and (3) the distance between the lesser trochanter and the proximal border of the isthmus is shorter by about 15 mm. The results suggested that the femoral component suitable for Asians should be dif- ferent (rom the currently-used components designed and manufactured mostly by European or American companies.

• 대한의용생체공학회:의공학회지
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• 제7권2호
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• pp.113-116
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• 1986

We investigated the structural geometry of thirty-eight Korean femurs. The purpose of this study is to identify major geometrical differences between Korean femurs 3nd others that we believe belong to Caucasians so that we would be able to get insights into the femoral component design that fits Asians including Koreans. We utilized computerized tomography (CT) images of femurs extracted from cadavers. The CT images were transformed into bitmap data by using a film scanner, and then analyzed by using a commercially available software called Image v.1.0 and a Macintosh IIci computer.The resulting data were compared with already published data. The major results show that the geometry of the Korean femurs is significantly different from that of Caucasians: (1) the anteversion angle and the canal flare index are greater by the amount of approximately 8˚ and 0.5, respectively, (2) the shape of the isthmus cross section is more round, and (3) the distance between the teaser trochanter and the proximal border of the isthmus is shelter by about 15 mm. The results suggested that the femoral component suitable for Asians should be different from the currently-used components designed and manufactured mostly by European or American companies.