• The korean journal of orthodontics
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• v.34 no.5 s.106
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• pp.394-407
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• 2004

The Purpose of this study was to evaluate the effect of the lower third molar on treatment time and distal en masse movement of the lower dentition in Giass III malocclusions. Thirty subjects (9 males and 27 females) were selected, all of whom were diagnosed as Glass III malocclusion and treated by fixed appliances without premolar and/or molar extraction. They were divided into three groups Group 1 consisted of 12 subjects. whose lower third molars were not extracted during the whole orthodontic treatment. Group 2 consisted of 8 subjects. whose lower third molars were extracted after WEAW application and before removal of the orthodontic appliances. Group 3 consisted of 10 subjects whose lower third molars were extracted before MEAW application. For each subject. overall treatment time and duration of MEAW application were determined. In addition. pre-treatment and post-treatment lateral cephalometric radiographs were analyzed. All data were Processed statistically with ANOVA, and the conclusions were as follows: There was no significant difference among the groups in overall treatment time However, duration of MEAW application was longer in Group 2 than in Group 1 or Group 3. The overjet that was established after orthodontic treatment was largest in Group 3, in which the lower third molars were extracted befor MEAW application. After orthodontic treatment, IMPA decreased in Group 3. but increased in Group 1 and Group 2. There was no significant difference among the three groups in the translation of lower second molars However the tipping movement of lower second molars was significantly different, highest in Group 2 and lowest in Group 1 Therefore. it is thought to be better for the orthodontic treatment of Class III malocclusions to extract the lower third molars before MEAW application. In Group 2, the mandibular plane angle was decreased as a result of forward rotation of the mandible This skeletal change was thought to bring about the difficulty of treatment.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.6
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• pp.515-525
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• 2005

Purpose of study: Lingual nerve damage can be caused by surgery or trauma such as physical irriatation, radiation, chemotherapy, infection and viral infection. Once nerve damage occurred, patients sometimes complain taste change and loss of taste along with serious disturbance of tongue. The purpose of this study was to evaluate the effects of unilateral lingual nerve transection on taste as well as on the maintenance of taste buds. Materials & Methods: Male Sprague-Dawley rats weighing 220-250g received unilateral transection of lingual nerve, subjected to the preference test for various taste solutions (0.1M NaCl, 0.1M sucrose, 0.01M QHCl, or 0.01M HCl) with two bottle test paradigm at 2, 4, 6, or 8 weeks after the operation. Tongue was fixed with 8% paraformaldehyde. After fixation, they were observed with scanning electron microscope(JSM-$840A^{(R)}$, JEOL, JAPAN) and counted the number of the dorsal surface of the fungiform papilla for changes of fungiform papilla. And, Fungiform papilla were obtained from coronal sections of the anterior tongue(cryosection). After cryosection, immunostaining with $G{\alpha}gust$(I-20)(Santa Cruz Biotechnology, USA), $PLC{\beta}2$(Q-15)(Santa Cruz Biotechnology, USA), and $T_1R_1$(Alpha Diagnostic International, USA) were done. Immunofluorescence of labeled taste bud cells was examined by confocal microscopy(F92-$300^{(R)}$, Olympus, JAPAN). Results: The preference score for salty and sweet tended to be higher in the operated rats with statistical significance, compared to the sham rats. Fungiform papilla counting were decreased after lingual nerve transaction. In 2 weeks, maximum differences occurred. Gustducin and $T_1R_1$ expressions of taste receptor in 2 and 4 weeks were decreased. $PLC{\beta}2$ were not expressed in both experimental and control group. Conclusion: This study demonstrated that the taste recognition for sweet and salty taste changed by week 2 and 4 after unilateral lingual nerve transection. However, regeneration related taste was occurred in the presence of preserving mesoneurial tissue and the time was 6 weeks. Our results demonstrated that unilateral lingual nerve damage caused morphological and numerical change of fungiform papilla. It should be noted in our study that lingual nerve transection resulted in not only morphological and numerical change but also functional change of fungiform papillae.

• Journal of dental hygiene science
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• v.9 no.4
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• pp.469-474
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• 2009

The purpose of this study was to examine the satisfaction level of parents with elementary school students in some metropolitan areas with the pit and fissure sealing program in a bid to raise awareness of the importance of the preventive treatment and accelerate the spread of it. The subjects in this study were 231 parents who had school children and resided in Seoul and Gyeonggi Province. After a self-administered survey was conducted in October and November 2008, the collected data were analyzed. The findings of the study were as follows; 1. As to places for receiving the preventive treatment, 111 respondents (48.1%) experienced pit and fissure sealing in dental clinics, and 88 respondents(38.1%) did that in dental hospitals. 177 people(76.6%) received that treatment from dentists, and 16 respondents(11.3%) did that from dental hygienists. 2. Concerning whether to be for or against the pit and fissure sealing program, more than half that numbered 143(61.9%) supported that program, and 88 respondents(38.1%) didn't. As for satisfaction level, they expressed the biggest satisfaction with the preventive effect of that treatment($3.92{\pm}.85$), and were least satisfied with the cost($1.91{\pm}.86$). 3. Regarding links between general characteristics and satisfaction level, they were statistically significantly different in satisfaction level with the cost according to residential area and the number of child, and age made a statistically significant difference to their satisfaction level with the preventive effect of it. 4. As for relationship between warranty term and whether to be for the pit and fissure sealing program or not, 45(31.5%) out of those who supported the program were provided with no warranty, and 32(36.4%) out of those who took a stand against it were provided with no warranty, either. Warranty was provided to 12(8.4%) respondents of the former group without a fixed term, but that's not the case for any of the latter. The warranty term made statistically significant differences to their agreement or disagreement to the program(p<0.05).

• Tuberculosis and Respiratory Diseases
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• v.42 no.4
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• pp.492-501
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• 1995

Background: Transforming growth factor- alpha(TGF-$\alpha$) may play important roles in carcinogenesis, tumor growth, and angiogenesis. Transforming growth factor-beta(TGF-$\beta$) are known to be involved in cell-cycle control and regeneration. TGF-$\alpha$ positively acts on growth control of many epithelial cells in contrast to the negative role of TGF-$\beta$. Method: To evaluate the possible role of TGF-$\alpha$ and TGF-$\beta$ in human primary lung cancers, the expression of TGF-$\alpha$ and TGF-$\beta$ were immmunohistochemically investigated in tissue sections from forty seven cases with lung cancers and ten cases with non-cancerous lung tissues. Recombinant cloned monoclonal antibody of TGF-$\alpha$ and neutralizing antibody of TGF-$\beta$ were employed as primary antibodies after dewaxing the formalin-fixed, paraffinized tissue sections. Results: TGF-$\alpha$ was expressed in the cytoplasms of tumor cells in thirty five cases of forty seven(74.5%) primary lung cancers, whereas the control expressed in two of ten brochial epithelial cells. The expression of TGF-$\alpha$ was disclosed in four cases of eleven(36.4 %) small cell carcinomas and thirty one cases of thirty six(86.1%) non-small cell carcinomas of the lung. Expressions of TGF-$\beta$ was discernible in bronchial epithelium in eight of ten non-cancerous lung tissues. The expression of TGF-$\beta$ was noted in the cytoplasms of tumor cells in eight cases of forty seven(17.0%) primary lung cancers. The expression of TGF-$\beta$ disclosed in two cases of eleven(18.2%) small cell carcinomas and six cases of thirty six(16.7%) non- small cell carcinomas of the lung. Conclusion: These findings suggest that up-regulation of TGF-$\alpha$ and down-regulation of TGF-$\beta$ are involved during development and growth of primary lung cancers.

• Tuberculosis and Respiratory Diseases
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• v.43 no.2
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• pp.164-172
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• 1996

Background : Transforming growth factor-$\beta$(TGF-$\beta$) may play a role in a variety of fibroproliferative disorders including pulmonary fibrosis via the induction of extracellular matrix accumulation. TGF-$\beta$ not only stimulates extracellular matrix production, but also decreases matrix degradation. Interstial lung diseases have demonstrated marked expression of TGF-$\beta$. Methods : To evaluate the possible role of TGF-$\beta$ in human pulmonary fibrosis, by using neutralizing antibody of TGF-$\beta$ we investigated immunohistochemically the expression of TGF-$\beta$ in the formalin-fixed, paraffin-embedded tissue sections of the 5 normal cases for the control, and a couple of pieces of tissues taken out of 3 cases with idiopathic pulmonary fibrosis, 3 cases with ILD from bleomycin toxicity, 3 cases with ILD from sarcoidosis, and 3 cases with ILD from eosinophilic granuloma. Results : In the 5 normal cases for the control, the TGF-$\beta$ was expressed in bronchial and alveolar epithelial cells. Up-regulation of the TGF-$\beta$ expression was showed in the interstitial fibroblast cells of alveolar septa in 5 pieces and proliferated alveolar pneumocytes in 1 piece among 6 pieces tissues taken out of 3 cases with idiopathic pulmonary fibrosis. Also up-regulation of the TGF-$\beta$ expression was showed in alveolar lining pneumocytes, intra-alveolar mononuclear cells, and epithelioid cells in most of cases of ILD from bleomycin toxicity, sarcoidosis and eosinophilic granuloma. Conclusion : These findings suggest that up-regulation of the TGF-$\beta$are involved in pathogenesis of interstitial lung fibrosis from variety of causes.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.2
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• pp.191-198
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• 2009

Statement of problem: Ceramics have been important materials for the restoration of teeth. The demands of patients for tooth-colored restorations and the availability of various dental ceramics has driven the increased use of new types of dental ceramic materials. Improved physical properties of theses materials have expanded its use even in posterior crowns and fixed partial dentures. However, ceramic still has limitation such as low loading capability. This is critical for long-span bridge, because bridge is more subject to tensile force. Purpose: The wire reinforced ceramic was designed to increase the fracture resistance of ceramic restoration. The purpose of this study was to evaluate the fracture resistance of wire reinforced ceramic. Material and methods: Heat pressed ceramic(ingot No.200 : IPS Empress 2, Ivoclar Vivadent, Liechtenstein) and Ni-Cr wire(Alfa Aesar, Johnson Matthey Company, USA) of 0.41 mm diameter were used in this study. Five groups of twelve uniform sized ceramic specimens(width 4 mm, thickness 2 mm, length 15 mm) were fabricated. Each group had different wire arrangement. Wireless ceramic was used as control group. The experimental groups were divided according to wire number and position. One, two and three strands of wires were positioned on the longitudinal axis of specimen. In another experimental group, three strands of wires positioned on the longitudinal axis and five strands of wires positioned on the transverse axis. Three-point bending test was done with universal testing machine(Z020, Zwick, Germany) to compare the flexural modulus, flexural strength, strain at fracture and fracture toughness of each group. Fractured ceramic specimens were cross-sectioned with caborundum disc and grinded with sandpaper to observe interface between ceramic and Ni-Cr wire. The interface between ceramic and Ni-Cr wire was analyzed with scanning electron microscope(JSM-6360, JEOL, Japan) under platinum coating. Results: The results obtained were as follows: 1. The average and standard deviation in flexural modulus, flexural strength and fracture toughness showed no statistical differences between control and experimental groups. However, strain was significantly increased in wire inserted ceramics(P<.001). 2. Control group showed wedge fracture aspects across specimen, while experimental groups showed cracks across specimen. 3. Scanning electron microscopic image of cross-sectioned and longitudinally-sectioned specimens showed no gap at the interface between ceramic and Ni-Cr wire. Conclusion: The results of this study showed that wire inserted ceramics have a high strain characteristic. However, wire inserted ceramics was not enough to use at posterior area of mouth in relation to flexural modulus and flexural strength. Therefore, we need further studies.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.2
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• pp.128-137
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• 2011

Purpose: Resonance frequency analysis, Periotest, and removal torque (RT) test were known as the methods to assess implant stability. The results of these methods are affected by the bone condition, implant diameter and shape. The purpose of this study is to access the meaning and the correlationship of the resonance frequency analysis, Periotest and RT test in osseointegration simulated acrylic resin when the engaged bone thickness and peri-implant bone defect are changed. Materials and methods: To simulate osseointegration, the fixture was fixed to an aluminum mold with a screw. Acrylic resin powder and liquid were poured into the mold for polymerization. The engaged resin thickness with implant was controlled. Simulated cortical bone thicknesses were 1, 3, 5 and 10 mm. Additional 1, 3 and 5 mm peri-implant bone defects were simulated. Three types of implants were used; 4 mm diameter implants of straight shape, 4 mm diameter implants of tapered shape and 5 mm diameter implants of tapered shape. Five fixtures per each type were tested in respective bone condition. Resonance frequency analysis and Periotest were evaluated in all bone conditions. Peak removal torque was measured at simulated cortical bone thicknesses of 1 and 3 mm. The statistical analysis was performed with the Kruskal-Wallis test, Mann-Whitney U test, and Spearman test using a 95% level of confidence. Results: With increasing engaged bone depth, the Implant Stability Quotient (ISQ) values increased and the Periotest values (PTVs) decreased (P<.001, P<.001). With increasing peri-implant bone defect, ISQ values decreased and PTVs increased (P<.001). When the diameter of implant increased, ISQ values increased and Periotest values (PTV) decreased (P<.001). There was a strong correlation between ISQ values and PTVs (r = -0.99, P<.001). Furthermore, the peak removal torque values had weak correlations with both ISQ values and PTVs (r = 0.52, P<.001 ; r = -0.52, P<.001). Conclusion: This study confirmed favorable implant stability with increasing engaged bone depth and implant diameter and decreasing peri-implant bone defect. ISQ values and PTVs showed strong correlation with each other and not with the peak removal torque values.

• Journal of The Korean Association For Science Education
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• v.37 no.4
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• pp.763-773
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• 2017

The purpose of this study is to investigate the impact of Argument-Based Inquiry (ABI) strategy on student's character competency. For this study, 51 grade 11 students (two classes) were selected to the role assignment (ABI-R group) and 46 students (two classes) were assigned to the non-role assignment group (ABI group). In the result, the role assignment group (ABI-R group) showed a statistically higher change in character competency than the group without role assignment (ABI group). Particularly, the ABI-R group has significantly higher grade than ABI group in empathy, responsibility, and respect among the sub-factors of character competency. However, in the case of the cooperation factor of character competency, the ABI group showed statistically significant higher grade than ABI-R group. The results of this study showed that Argument-Based Inquiry (ABI) as teaching and learning strategies in science can contribute to the enhancement of human character competency. In addition, we suggest that students should be actively involved in the class through role assignment, but it is necessary to present the class situation so that they can be actively engaged according to the problem situation rather than being fixed in a given role.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.2
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• pp.209-222
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• 2011

Missing anterior teeth can be replaced using any of a number of methods. Patients may choose to replace missing teeth with a prosthesis that is either removable, fixed, or retained with implants. For patients faced with financial, anatomical, and/or esthetic limitations, the edentulous region can be restored successfully and esthetically with a properly designed and fabricated rotational path RPD. The rotational path RPD is a partial removable dental prosthesis that incorporates a curved, arcuate, or variable path of placement allowing one or more of the rigid components of the framework to gain access to and engage an undercut area. The rigid retainer must gain access to the infrabulge portion of the tooth by rotating into place. Either a minor connector or proximal plate provides retention through its intimate contact with a proximal tooth surface. A specially designed dovetails or asymmetric rest seats provides support and embracing effects. Correctly designed and fabricated rotational path RPD can provide improved esthetics, cleanliness, and retention. But rotational path RPDs are technique sensitive since the rotational path RPD has little margin of laboratory error that rigid retainers cannot be adjusted like conventional clasps can, RPD framework must be remade once the retention is lost. The sufficient understanding of the concept for the rotational path RPD is required for clinically successful treatment. This clinical report describes in detail the theoretical, laboratory considerations and the treatment of a patient with an anterior maxillary edentulous area treated by an AP path rotational RPD that had a difficulty in long term maintenance and describes another clinical case in which more reasonable treatment procedures were approached after analyzing the former case.

• Journal of the Korean Chemical Society
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• v.37 no.3
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• pp.344-350
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• 1993

25,26,27,28-Tetraacetoxycalix[4]arene·monohydrate is orthorhombic, space group Pbca with a = 14.979(4), b = 15.154(4), c = 27.890(3) ${\AA}$, Z = 8, V = 6330.6 ${\AA}^{-3}$, D$_c$ = 1.28 $g{\cdot}cm^{-3}$, (Mo K${\alpha}$) = 0.71069 ${\AA}$, ${\mu}$ = 0.86 cm$^{-1}$, F(000) = 2600, and R = 0.069 for 3376 unique observed reflections with I > 1.0 ${\sigma}$(I). The structure was solved by direct methods and refined by cascade diagonal least-squares refinement. All the C-H bond lengths(= 0.96 ${\AA}$), the methyl groups and the methylene groups are fixed and refined as the rigid groups with ideal geometry. The macrocycle exists in the 1,3 alternate conformation (by Conforth) making the angles of 110.7, 684, 113.7 and 68.8$^{\circ}$ between the benzene rings and the methylenic mean plane, and four each acetoxy groups are twisted away from their own benzene rings with the angles of 68.2, 97.6, 78.9 and 71.3$^{\circ}$, respectively. The relative dihedral angles between two opposite side of the benzene rings are 135.6$^{\circ}$ for the rings (1) and (3) and 135.2$^{\circ}$ for (2) and (4). A water molecule which has nearly the same height of the methylenic plane of the macrocycle in the c-axis, is located within the distances of 2.942(5) ${\AA}$ from the O(8) atom of the carbonyl group and 2.901 ${\AA}$ from, another O(2)(1/2-x, -1/2＋y, z). The shortest contact between the molecule is 3.193 ${\AA}$ from the O(4) to the C(3)(1/2＋x, 1/2-y,-z).