• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.157-157
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• 2017

Titanium and its alloys that have a good biocompatibility, corrosion resistance, and mechanical properties such as hardness and wear resistance are widely used in dental and orthopedic implant applications. They can directly connect to bone. However, they do not form a chemical bond with bone tissue. Plasma electrolytic oxidation (PEO) that combines the high voltage spark and electrochemical oxidation is a novel method to form ceramic coatings on light metals such as titanium and its alloys. This is an excellent reproducibility and economical, because the size and shape control of the nano-structure is relatively easy. Silicon (Si), manganese (Mn), and magnesium (Mg) has a useful to bone. Particularly, Si has been found to be essential for normal bone, cartilage growth and development. Manganese influences regulation of bone remodeling because its low content in body is connected with the rise of the concentration of calcium, phosphates and phosphatase out of cells. Insufficience of Mn in human body is probably contributing cause of osteoporosis. Pre-studies have shown that Mg plays very important roles in essential for normal growth and metabolism of skeletal tissue in vertebrates and can be detected as minor constituents in teeth and bone. The objective of this work was to study nucleation and growth of bone-like apatite formation on Ti-6Al-4V in solution containing Mn, Mg, and Si ions after plasma electrolytic oxidation. Anodized alloys was prepared at 270V~300V voltages. And bone-like apatite formation was carried out in SBF solution for 1, 3, 5, and 7 days. The morphologies of PEO-treated Ti-6Al-4V alloy in containing Mn, Mg, and Si ions were examined by FE-SEM, EDS, and XRD.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.80-80
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• 2017

Titanium and its alloys that have a good biocompatibility, corrosion resistance, and mechanical properties such as hardness and wear resistance are widely used in dental and orthopedic implant applications. However, they do not form a chemical bond with bone tissue. Plasma electrolytic oxidation (PEO) that combines the high voltage spark and electro-chemical oxidation is a novel method to form ceramic coatings on light metals such as tita-nium and its alloys. This is an excellent re-producibility and economical, because the size and shape control of the nano-structure is relatively easy. Silicon (Si), manganese (Mn), and magne-sium (Mg) have a useful to bone. Particularly, Si has been found to be essential for normal bone, cartilage growth, and development. Mn influences regulation of bone remodeling be-cause its low content in body is connected with the rise of the concentration of calcium, phosphates and phosphatase out of cells. Pre-studies have shown that Mg plays very im-portant roles in essential for normal growth and metabolism of skeletal tissue in verte-brates and can be detected as minor constitu-ents in teeth and bone. In this study, Electrochemical behavior of plasma electrolytic oxidized films formed in solution containing Mn, Mg and Si ions were researched using various experimental in-struments. A series of Si-Mn-Mg coatings are produced on Ti dental implant using PEO, with the substitution degree, respectively, at 5 and 10%. The potentiodynamic polarization and AC impedance tests for corrosion behav-iors were carried out in 0.9% NaCl solution at similar body temperature using a potentiostat with a scan rate of 1.67mV/s and potential range from -1500mV to + 2000mV. Also, AC impedance was performed at frequencies anging from 10MHz to 100kHz for corrosion resistance.

• Archives of Reconstructive Microsurgery
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• v.14 no.2
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• pp.85-94
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• 2005

Purpose: This study was to evaluate the effect of ${\alpha}-lipoic$ acid, a potent free radical scavenger, on the expression of active form of extracellular signal-regulated kinase (pERK1/2) proteins from hindlimb muscles of rats following ischemia-reperfusion injury. Material and methods: 64 health, $280{\sim}350\;g$ weighted Sprague-Dawley male rats were used. In order to make a muscle flap, the gastrocnemius (GC) and soleus (SOL) muscles were dissected and elevated. The popliteal artery was occluded for 4hours and reperfused for 10 minutes, 30 minutes, 1 hour, 2 hours and 4 hours, respectively. Results: The ischemia by occlusion of the popliteal artery itself caused a minimal change in expression of phosphorylated form of proteins observed in hindlimb muscle. In contrast, after 4 hours of ischemia, immunoreactivity for pERK1/2 in the GC muscle showed dual peaks at 10 minutes and 4 hours after reperfusion. In ${\alpha}-lipoic$ acid treated group, the expression of pERK1/2 was increased significantly compared to I/R-only group. Conclusion: These results suggest that ${\alpha}-lipoic$ acid may protect I/R injury of the skeletal muscle through free radical scavening and activation of intracellular pERK1/2 expression.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.2
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• pp.200-207
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• 1996

In patients with unilateral condylar hyperplasia, increased length of the condylar neck causes deviation of the mandible to the opposite site, resulting in facial asymmetry, but the arch form and general contour of the displaced mandible is approximately symmetric. So, the unilateral condylectomy have been prefered surgical method among the surgeons. The purpose of this study is to analyze the postoperative results comparatively following two different surgical methods, condylectomy and ramus surgery, in unilateral condylar hyperplasia. Case of 6 patients with the unilateral condylar hyerplasia were analyzed in this study, 3 case of the condylectomy only, 3 cases of the ramus surgery, Clinical and radiographic evaluations were tried for comparison. In conclusion, comparative results between two groups did not show any significant difference, but we confirmed that unilateral condylectomy could be a excellent surgical methods in unilateral condylar hyperplasia thinking over the unique morphological characteristics of it.

• The korean journal of orthodontics
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• v.19 no.2
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• pp.95-108
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• 1989

This study intended to calculate the cephalometric norms of Korean adult and to compare those with norms of the North American Caucasian by Moyers. Cephalometric headplates of 41 males and 31 females ranged in age from eighteen to twenty-six with normal occlusion and pleasing face were employed for this investigation. The tracings of the standard lateral cephalograms were analyzed by Moyers' method. As a result of this study, the following conclusion can be made. 1. Norms of Korean adult male and female were calculated. 2. There was no significant sexual difference in the basic craniofacial morphology. 3. The size of craniofacial skeleton was larger in male than in female. 4. The Korean male showed lower value of mandibular plane angle to craial base than that of the Caucasian male. 5. There was no significant difference in the anterior total facial height, however, in the posterior facial height the Korean male was larger than the Caucasian male, which manifested that the Korean male held more square-shaped profile. 6. The anteroposterior length of anterior and posterior cranial base, maxillary and mandibular skeletal and dentoalveolar effective length of the Korean male were shorter than those of the Caucasian male, and this suggested that the craniofacial profile depth of the Korean male was shorter than that of the Caucasian male.

• The korean journal of orthodontics
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• v.44 no.6
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• pp.330-341
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• 2014

A 19-year-old woman presented to our dental clinic with anterior crossbite and mandibular prognathism. She had a concave profile, long face, and Angle Class III molar relationship. She showed disharmony in the crowding of the maxillomandibular dentition and midline deviation. The diagnosis and treatment plan were established by a three-dimensional (3D) virtual setup and 3D surgical simulation, and a surgical wafer was produced using the stereolithography technique. No presurgical orthodontic treatment was performed. Using the surgery-first approach, Le Fort I maxillary osteotomy and mandibular bilateral intraoral vertical ramus osteotomy setback were carried out. Treatment was completed with postorthodontic treatment. Thus, symmetrical and balanced facial soft tissue and facial form as well as stabilized and well-balanced occlusion were achieved.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1999.06a
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• pp.115-127
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• 1999

The charged clusters or particles, which contain hundreds to thousands of atoms or even more, are suggested to form in the gas phase in the thin film processes such as CVD, thermal evaporation, laser ablation, and flame deposition. All of these processes are also used in the gas phase synthesis of the nanoparticles. Ion-induced or photo-induced nucleation is the main mechanism for the formation of these nanoclusters or nanoparticles inthe gas phase. Charged clusters can make a dense film because of its self-organizing characteristics while neutral ones make a porous skeletal structure because of its Brownian coagulation. The charged cluster model can successfully explain the unusual phenomenon of simultaneous deposition and etching taking place in diamond and silicon CVD processes. It also provides a new interpretation on the selective deposition on a conducting material in the CVDd process. The epitaxial sticking of the charged clusters on the growing surface is gettign difficult as the cluster size increases, resulting in the nanostructure such as cauliflowr or granular structures.

• The Journal of Korean Medicine
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• v.27 no.3 s.67
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• pp.26-37
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• 2006

Determination and differentiation of cells in the skeletal muscle lineage is positively regulated by cell-cell contact. Differentiation proteins proposed to mediate this effect include both classical MyoD and MEF members; potential interactions between the promyogenic activities of these classes of protein, however, are unknown. We show here that MyoD and MEF, two promyogenic family members that relate to each other in a cis fashion, form interactions with MyoD and MEF. These proteins contain myosin-heavy chainsand are enriched at sites of cell-cell contact between myoblasts. Therefore, in differentiation of MyoD and MEF from Chungsimyeonjaeum interact dependently, suggesting that the interactions occur in a cis fashion; consistent with this conclusion, MyoD-mediated differentiation is required for myoblasts to occur by Chungsimyeonjaeum. Inhibition in myoblasts of a MyoD by Staurosporine in its ability to associate with MEF interferes with differentiation as assessed by morphological and transcription levels, suggesting that this interaction is functionally important in myogenesis. Also, some of the differentiation-mediated proteins that are required for myogenesis seem to be based on interdependent activities of the promyogenic classical smad-subfamily.

• The korean journal of orthodontics
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• v.20 no.2
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• pp.391-407
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• 1990

This study was performed to establish the cephalometric standards and to observe the nature of anatomic fit in the internal structural relationship of the craniofaciodental complex of the normal Korean by means of Moyers' method. Lateral cephalograms of 143 males and 144 females with normal occlusion and acceptable profile from 6 to 25 years of age, which were consisted of 5 groups that were 6 year-, 9 year-, 12 year-, 15 year- and adult-group were obtained. Data were gathered by traced digitizing the cephalograms and were statistically analyzed. The findings can be summerized as follows. 1. Norms of Korean males, females and both sexes in each group were established. 2. There was little significant sexual dimorphism in the form of craniofacial skeleton of all age groups. 3. The height and length of craniofacial skeleton was alike in each sexes in the 6 year-, 9 year- and 12 year-group, whereas it was larger in male than in female in the 15 year- and adult-group. 4. There were no significant sexual differences in the internal structural relationship of the craniofacial skeleton in all age groups.

• Korean Journal of Environmental Biology
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• v.30 no.2
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• pp.151-155
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• 2012

Korean freshwater turtles are divided into native turtles, Chinemys reevesii in Geoemydidae, Pelodiscus sinensis in Trionychidae, and imported turtles, Trachemys scripta elegans, T. s. scripta, Pseudemys rubriventris and Ocadia sinensis. In this study, we determined the distribution of Korean freshwater turtles based on a field study and literature study, and considered the taxonomic position of unidentified native turtles. The study was carried out between May 2010 and November 2011 during the day time, and the capturing tool used to collect turtles consisted of net and metal frame. C. reevesii and P. sinensis were found in 16 and 11 places, respectively. C. reevesii, which inhabits the Korean peninsula, is a taxonomically controversial species, but it is presumed that the turtle belongs to Mauremys. Moreover recent taxonomic studies of the soft-shell turtle have shown that the Korean native species is P. maackii, and P. sinensis was imported from abroad and has been in the natural habitats of Korea since 1970s. The exterior shape and skeletal form of P. maackii and P. sinensis are nearly similar. However, the skin color and yellow spots on the shell could be used to distinguish the two species.