• The Journal of Korean Academy of Prosthodontics
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• v.37 no.2
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• pp.242-255
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• 1999

The purpose of this study was to estimate the morphology and the size of permanent mandibular molar in Korean Adult. The 100 dental college students with a normal dentition and without any dental prosthesis and severe caries were selected for this study The subjects were taken impression to make study model. On the study model, the 5 dentists measured those sizes and estimated morphological structures with a calipers, a Boley gauge and a protractor. The results were as follows; 1. The clinical crown height, width, thickness and the other anatomical structures had symmetrical relationship between the left and right mandibular molar. 2. In the clinical crown height aspect, the buccal crown heights always were higher than the lingual crown height. The heights of the each surface, the buccal or lingual surface, were gradually decreased from the 1st molar to the 2nd molar and the difference on the buccal surface was higher than that on the lingual surface. 3. In the clinical crown width aspect, the mesiodistal measurement of the mandibular 1st molar was higher than that of the mandibular 2st molar. 4. In the clinical crown thickness aspect, the mesial buccolingual measurement was highest on the mandibular 1st molar and the distal buccolingual distance was lowest on the mandibular 2nd molar. This distal thickness of the mandibular molar always was higher than that of the mesial half. 5. The well-developed mesiobuccal groove of the 1st molar was observed more often than that of the 2nd molar. The buccal pit was also observed more frequently at the 1st molar, but the frequency(35%) was not high. 6. The occlusal type according to the number of cusp was almost 5-cusp(98%) in the 1st molar and was also 5-cusp(63%) in the 2nd molar. The frequency of the 6th cusp was 31% in the 1st molar and was 22% in the 2nd molar. The frequency of the 7th cusp was below 2of in the both teeth. 7. In the buccolingual intercuspal distance aspect of the mesial and distal half, the intercuspal distance of distal half was higher than that of the mesial half on the 1st and 2nd molar, but the difference on the 1st molar was higher than that on the 2nd molar. 8. The difference between the widths of the buccal and lingual half was 1.5mm in the 1st molar and 0.8mm in the 2nd molar. Therefore the lingual convergency of the occlusal surface was more higher in the 1st molar. 9. On the mandibular 1st and 2nd molar, the distobuccal external angle was more acute than the mesiobuccal external angle. But the mesiobuccal internal angle was more acute than the distobuccal internal angle. 10. When the mandibular molar was a 5-cusp type, the development of the distal cusp on the 1st molar was better than that on the 2nd molar. The difference between the cusps was around 0.4mm.

• The Journal of Advanced Prosthodontics
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• v.16 no.4
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• pp.212-220
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• 2024

PURPOSE. This cone-beam computed tomography (CBCT) study aimed to analyze the anatomical characteristics of alveolar bone at mandibular first molar (MFM) and their implications for immediate implant placement surgery. MATERIALS AND METHODS. 100 patients with 140 MFMs were reviewed retrospectively. We first performed a 3D reconstruction of the patient's CBCT data to determine a reference plane with ideal implant placement and orientation. The following parameters of MFM region were analyzed: mesial-distal socket size (MDSS), buccal-lingual socket size (BL-SS), root furcation fornix to inferior alveolar nerve (IAN) distance (RF-I), interradicular bone thickness (IRB), mesial/distal root apex to the IAN distance (MRA-I/DRA-I), thickness of the buccal/lingual bone of the mesial root (MR-B/MR-L), thickness of the buccal/lingual bone of the distal root (DR-B/DR-L). RESULTS. The MD-SS of MFM was 8.74 ± 0.76 mm, and the BLSS was 8.26 ± 0.72 mm. The MR-B, DR-B was 1.01 ± 0.40 mm and 1.14 ± 0.50 mm, and the difference was statistically significant (P = .001). The values of the MR-L, DR-L were 2.71 ± 0.78 mm and 3.09 ± 0.73 mm, and the difference was also statistically significant (P < .001). The mean distance of RF-I was 15.68 ± 2.13 mm, and the MRA-I was 7.06 ± 2.22 mm, which was greater than that of DRA-I (6.48 ± 2.30 mm, P < .001). The IRB at 2 mm, 4 mm apical from the furcation fornix, and at apex level was 2.81 ± 0.50 mm, 3.30 ± 0.62 mm, and 4.44 ± 1.02 mm, respectively. CONCLUSION. There is relatively sufficient bone mass in interradicular bone in height, but an adequate width is lacking for the bone between the mesial and distal root after the extraction of the MFM for immediate implantation. The thickness of the MFM buccal bone is relative thin, especially for the mesial root.

• Journal of Veterinary Clinics
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• v.24 no.2
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• pp.280-283
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• 2007

A 6-year-old male dog was referred to Animal Medical Center, Chonbuk National University with large distal extremity abrasion wound to the hind limb by automobile accident. The wound was reconstructed with an autogenous, full-thickness skin mesh graft. The graft was harvested from the ventrolateral abdominal wall and transplanted to the wound. The skin mesh graft survived successfully without any noticeable complications. Successful grafting requires asepsis, an adequately prepared recipient bed through the surgical debridement and lavage, proper harvesting and preparation of the graft. Full-thickness skin mesh graft has lesser skin contraction which prevents formation of scar. Meshing the graft provides more graft flexibility over uneven, convex and concave surfaces and allows adequate drainage. The full-thickness skin mesh graft can be successfully used for the treatment of large distal skin wounds in dogs.

• Journal of Chest Surgery
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• v.32 no.10
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• pp.883-890
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• 1999

Long term patency of arterial graft has been better than venous graft and redo coronary artery bypass grafting has been increasing, therefore, there has been an increasing need for alternative arterial grafts except internal thoracic artery(ITA). Material and Method: Right gastroepiploic arteries(RGEA) were harvested from 100 patients who had received gastrectomy for gastric cancer or ulcer. ITAs were obtained from 10 patients undergoing coronary artery bypass grafting. The length of RGEA was measured from the pyloric ring. Items of the morphometric and histologic study at the pyloric ring and sites of the 10cm and 20cm RGEA from the pyloric ring were luminal diameter, intimal thickness, medial thickness, wall thickness, degree of intimal hyperplasia, intimal thickness, medial thickness, wall thickness, degree of intimal hyperplasia, intimal thickness index, medial thickness index, and the number of discontinuities of the internal elastic lamina. Similar items were applied to the proximal site of ITAs. Result: The length of RGEA was 23${\pm}$2.7cm(range 17∼31cm). Comparing the 20cm RGEA with ITA, intimal thickness, medial thickness, wall thickness, and degree of intimal hyperplasia did not show any difference(p>0.05). However, 20cm RGEA was greater than ITA at the luminal diameter, intimal thickness index, and the number thickness and wall thickness in each site of the RGEA(pyloric ring, 10cm, 20cm) decreased from the pyloric ring to the distal sites(p<0.05). The degree of intimal hyperplasia and the number of discontinuities of the internal elastic lamina did not show any difference between the pyloric ring and 10cm, however, those of 20cm were smaller than these sites(p<0.05). RGEA had more number of discontinuities of the internal elastic lamina and rich smooth muscle cells in the media than ITA. Conclusion: The length and diameter of RGEA is good enough to reach most of the coronary arteries. Moreover, long term patency of RGEA may be improved, if anastomosed in the distal site.

• Journal of Korean Neurosurgical Society
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• v.55 no.5
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• pp.244-247
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• 2014

Objective : The aim of this study was to evaluate the microanatomy and histological features of the central myelin in the root exit zone of facial nerve. Methods : Forty facial nerves with brain stem were obtained from 20 formalin fixed cadavers. Among them 17 facial nerves were ruined during preparation and 23 root entry zone (REZ) of facial nerves could be examined. The length of medial REZ, from detach point of facial nerve at the brain stem to transitional area, and the thickness of glial membrane of central myelin was measured. We cut brain stem along the facial nerve and made a tissue block of facial nerve REZ. Each tissue block was embedded with paraffin and serially sectioned. Slices were stained with hematoxylin and eosin (H&E), periodic acid-Schiff, and glial fibrillary acid protein. Microscopy was used to measure the extent of central myelin and thickness of outer glial membrane of central myelin. Thickness of glial membrane was examined at two different points, the thickest area of proximal and distal REZ. Results : Special stain with PAS and GFAP could be differentiated the central and peripheral myelin of facial nerve. The length of medial REZ was mean 2.6 mm (1.6-3.5 mm). The glial limiting membrane of brain stem is continued to the end of central myelin. We called it glial sheath of REZ. The thickness of glial sheath was mean $66.5{\mu}m(40-110{\mu}m$) at proximal REZ and $7.4{\mu}m(5-10{\mu}m$) at distal REZ. Conclusion : Medial REZ of facial nerve is mean 2.6 mm in length and covered by glial sheath continued from glial limiting membrane of brain stem. Glial sheath of central myelin tends to become thin toward transitional zone.

• The Journal of Korean Academy of Prosthodontics
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• v.36 no.1
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• pp.104-119
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• 1998

The purpose of this study was pertinent design of the framework of the fixed bone anchored bridge using implants in the edentulous mandible through analysis of stress distribution by the three dimensional finite element analysis method. The results were as follows: 1. The L-shaped framework was favorable in restoring the edentulous mandible by implants and fixed bone anchored bridge. 2. The structure of the framework should be designed to endure the occlusal load because of stress concentration at the most distal abutment of the framework. 3. The stress at the distal implant where cantilever starts was twice as much as that of other portions. 4. Compressive stress was generated on the framework of the mesial side of the distal implant and extrusive force was induced to the mesially positioned implants. 5. The height of vertical plate was high as possible as can be to distribute stresses concentrating bucco-lingually and labio-lingually in the framework between abutments, 6. Reinforcement of the horizontal plate thickness was needed because stress was loaded more on the horizontal plate than on the vertical plate of the framework. 7. Lengthening of the vertical plate can compensate for any limitations in horizontal plate width.

• Archives of Reconstructive Microsurgery
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• v.22 no.1
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• pp.38-41
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• 2013

A 31-year-old female patient presented with a skin and soft tissue defect measuring $8{\times}6cm$ in size with exposure of the extensor hallucis longus tendon and the first metatarsal bone after metatarsal lengthening for brachymetatarsia. The defect was covered with a distally based dorsalis pedis flap based on the distal communicating branch of the dorsalis pedis artery. Secondary defect was covered by a split thickness skin graft. There was congestion of the flap tip after the operation; however, it was resolved using medical leeches and anti-coagulants. No necrosis or infection was encountered and the contour of the flap was satisfactory. There was no donor site morbidity. Reverse dorsalis pedis flap has not been commonly used due to the anatomical variation and uncertainty, which is different from the reverse radial forearm flap. However, when faced with the challenge of a moderate soft tissue defect of the distal forefoot, we believe that the reverse dorsalis pedis flap offers a good option with various advantages.

• Restorative Dentistry and Endodontics
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• v.14 no.2
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• pp.1-4
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• 1989

To determine the thickness of coronal hard structure the minimal distance between pupal surface and outer surface of crown was measured by means of Bowley gauge on extracted first molars. Upper(28 teeth) and lower(24 teeth) were carefully collected from 30-39 years of age and male. The teeth were split mesio-distally through central pit. On the split surface various part which are deeply related in cavity preparation were measured (schematic drawing). The results were as follows: A : Distance from mesio-cervical enamel to pulp chamber surface. upper $2.63{\pm}0.19$(mm) Lower $2.18{\pm}0.27$(um) B : Distance from mesial chamber ceiling to mesial surface upper $2.75{\pm}0.34$ Lower $2.62{\pm}0.31$ C : Distance from mesial chamber ceiling to occlusal surface upper $3.82{\pm}0.51$ Lower $3.49{\pm}0.50$ D : Distance from distal chamber ceiling to occlusal surface upper $4.28{\pm}0.69$ Lower $3.90{\pm}0.52$ E : Distance from distal chamber ceiling to distal surface upper $2.79{\pm}0.45$ Lower $2.41{\pm}0.40$ F : Distance from disto cervical enamel to pulp chamber surface upper $2.49{\pm}0.24$ Lower $2.39{\pm}0.25$.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.553-557
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• 2008

The effects of cheonggukjang and doenjang on bone mineral density, trabecular area and cortical thickness of the tibia, and serum osteocalcin level in ovariectomized rats were investigated. After 4 weeks, bone mineral density, bone trabecular area, the cortical thickness index, and serum osteocalcin level were analyzed. The cheonggukjang and doenjang diet groups showed significant prevention of ovariectomized (OVX)-related body weight gain. Whole body bone mineral density of the OVX group was significantly lower than that of the sham group, whereas the cheonggulgang and doenjang diets resulted in complete restoration of bone mineral density. Trabecular area in the proximal diaphysis and cortical thickness in the distal diaphysis of the tibia were increased significantly in the cheonggukjang and doenjang diet fed groups. The cheonggukjang and doenjang diets significantly reduced serum osteocalcin level in the OVX rats. These results suggest that cheonggukjang and doenjang might have inhibitory effects on osteoporosis, by showing accelerated bone formation in OVX rats.

• Archives of Plastic Surgery
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• v.46 no.1
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• pp.57-62
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• 2019

Background Full-thickness nail bed defects with significant exposure of the distal phalanx are typically challenging to reconstruct. We describe a novel method of nail bed defect reconstruction using a thenar fascial flap combined with nail bed grafting. Methods Full-thickness nail bed defects were reconstructed in a 2-stage operation involving the placement of a thenar fascial flap and subsequent nail bed grafting. A proximally-based skin flap was designed on the thenar eminence. The flap was elevated distally to proximally, and the fascial layer covering the thenar muscle was dissected proximally to distally. The skin flap was then closed and the dissected fascial flap was turned over (proximal to distal) and inset onto the defect. The finger was immobilized for 2 weeks, and the flap was dressed with wet and ointment dressings. After 2 weeks, the flap was divided and covered with a split-thickness nail bed graft from the great toe. Subsequent nail growth was evaluated on follow-up. Results Nine patients (9 fingers) treated with the novel procedure were evaluated at follow-up examinations. Complete flap survival was noted in all cases, and all nail bed grafts took successfully. Five outcomes (55.6%) were graded as excellent, three (33.3%) as very good, and one (11.1%) as fair. No donor site morbidities of the thenar area or great toe were observed. Conclusions When used in combination with a nail bed graft, the thenar fascial flap provides an excellent means of nail bed reconstruction.