• Journal of Korean society of Dental Hygiene
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• v.9 no.2
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• pp.147-163
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• 2009

This study was attempted in order to look into 'Assist work' as to Implant system which dental hygienists perform in a clinical field. Subjects of this research were 362 dental hygienists who work at general hospital, University hospital, dental hospital, and dental clinics located in Seoul, Kyeong-gi, In-chon, and Jeon-buk area. As to research tool, we produced questionnaire which was comprised of the total 25 items regarding 3 of general features (age, career of dental hygienist, and personality), 6 of implant system assist work, 3 of Informed consent before surgery, 6 of preoperative preparation and maintenance related business, and 7 items related to postoperative maintenance. By using SPSS program, collected data was analyzed. Results of analysis in this study were as follow; 1. As to implant related education, dental hygienists' experience of education was high as 77.7%, and the people who is needed more education was 86.3%. Consequently, dental hygienists' concern about the implant related education was very high. 2. It was observed that most of informed consent making approvement by announcement to the surgical operation was made by dental hygienist before implant as 95%. 3. Over 80% of dental hygienists performed acquisition of cleanliness technology, motivation, back up articles preparation, treatment area arrangement, and etc. which we can check by preoperative maintenance items. In particular, response about the motivation was very high as more than 90%. 4. When performing an operation, in the case of disinfecting finger was low for 53.9% and the method was mainly washing with drug solution, and gown sterilization was performed only in 52.2%. Therefore education regarding disinfection was urgently needed. 5. Significance of education could be known that answers of hygienists experienced education appeared highly in items of maintenance method and there was statistically significant difference(p<0.05). 6. In case that assist work were 21cases or greater, agitation measurement was the most many performed in 68.9% and difference was showed up significantly(p<0.001). 7. Evaluation about periodontal tissue was high in dental hygienists who had experienced education and also there was statistically significant difference. In conclusion, assist work of dental hygienists was very comprehensive when implant surgery was performed, and all of items excluding hand disinfection or gown disinfection were highly showed up in most of hygienists. However, since there is the limit that we didn't investigate the quality of performing contents. It is considered that further study regarding the content has to be progressed for supporting this result in the future.

• The Korean Journal of Food And Nutrition
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• v.25 no.2
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• pp.308-316
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• 2012

Proper skin care promotes good metabolism and the biological activity of skin, helps maintain the skin in a healthy and beautiful state when combined with nutritional nourishment. Health functional foods are being used for the purpose of enhancing efficient skin care. Health functional foods related to skin care maintain the epidermis, dermal fibroblast layer and subcutaneous tissue that form the skin. Efficient functional foods alleviate the signs of endogenous aging that come with getting older and exogenous aging caused by sunlight. Even though the field of skin care related to health functional foods has received less attention and been the subject of less research compared to functional cosmetics which are developing widely, this area of skin care that maintains and improves the layer of dermal fibroblast through the intake of food, is expected to progress with the commercialization of products in many fields when the related technical research development is galvanized and the related patents are applied for. Research into health functional foods related to skin care in Korea started rather late in comparison to other advanced countries where patents for relevant techniques have been applied for since 1990's together with research conducted on how they might be used for practical purposes. This study used the key words 'skin care, health functional food' to search for Korean patents that have been applied for at the Korean Intellectual Property Office from 1983 to 2011 using the KIPRIS database, in order to help researchers in the related fields by organizing the patented formulas for health functional foods for skin care which have gained attention recently. According to the number of registrations in each industry field, the total number of patents was 1,120 we screened the major patents among them, the field with the largest number was food foodstuff non-alcoholic beverage and preparation or treatment(A23L) with 135, then natural plant medicine & medical supplies and cosmetics(A61K) with 112, microorganisms or enzymes(C12N) with 63, heterocyclic compounds(C07D) with 44, horticulture or cultivation of sea weeds, forestry(A01G) 16 times, listed from the highest to the lowest number of applications. It has been revealed that food, foodstuff, non-alcoholic beverage and preparation or treatment(A23L) was the industry field where the most patents for health functional foods related to skin care were registered.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.225-230
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• 1983

Aqua-regia method is reported for simultaneous determination of potassium, sodium, calcium, magnesium, zinc, manganese, copper and iron in high-fat fish tissue. Samples are digested with conc nitric and conc hydrochloric acid in a volumetric flask. After digestion, aqua-regia extracts of samples are analyzed by direct flame atomic absorption spectrophotometry. The aqua-regia method is compared with dry ashing method and $H_{2}SO_{4}-HNO_{3}$ method. For quantiative determination of calcium, magnesium and zinc, the aqua-regia method and dry ashing method are superior to $H_{2}SO_{4}-HNO_{3}$ method. In case of the other elements-potassium, sodium, manganese, copper and iron-the three methods gave the similar results. Because samples can be processed by aqua-regia method easily, rapidily, cheaply and safely, aqua-regia method is suitable for the routine preparation of a large number of samples simultaneously.

• Journal of the Korean Chemical Society
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• v.60 no.3
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• pp.187-193
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• 2016

In this study, preparation of positively and negatively charged carbon nanotube (CNT)-collagen (CG) hydrogels with pH sensitive characteristic was reported. The positive and negative characteristics of the prepared hydrogels were created by introduction of positively functionalized CNT-NH₂ and negatively functionalized CNT-COOH, respectively, into the collagen hydrogel. The surface charge of CNTs (CNT-NH₂ and CNT-COOH), CG and CNTs/CG hydrogels was measured by Zetasizer. The swelling ratios of CNT-NH₂/CG and CNT-COOH/CG hydrogels in aqueous solution were checked by measuring of weight changes of the hydrogels in the range of pH 2~10. In detail, the positively charged CNT-NH₂/CG hydrogel swelled up to 5% at pH 4 in comparison to the weight at pH 7, while the negatively charged CNT-COOH/CG hydrogel swelled up to 10% at pH 10. The prepared CNT-NH₂/CG and CNT-COOH/CG hydrogels will be very useful as pH sensitive oral drug-delivering systems for gastrointestine (pH ~2) and small intestine (pH ~9), respectively.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.2
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• pp.141-151
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• 2013

The nano-surface modification techniques could be classified; internal modifications which enhance surface roughness and porosity in nano level and external modifications as nano particle coating. Nano-modified implant surface has various morphograpies such as nanotube, nanopit, nanonodule and polymorphic structures. Creating surface depends upon preparation method and material, however, there is no standard preparation technique not yet. The nano-modified surfacet is electrochemically stable comparing with the surface modified in micron level. Nano-modified surface has little cytotoxicity, stimulates osteoblast proliferation and differentiation. Moreover, it decreases soft tissue intervention by interrupting the proliferation of fibroblast. Nanostructure has similar size and shape with cells and proteins, consequently leads to good biocompatibility and enhanced osseointegration. However, the actual effect in vivo is limited, due to the distance of effect. Even if nano-modified surface has antibiotic property due to photocatalysis, short duration time makes clinical application questionable. Further investigations should focus on the optimal nano-modified surface, which has many potentials.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.477-486
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• 1998

Recently the development of rotary instrument makes it possible that in root canal treatment operator saves much more time, maintans original curved canal shape and easily prepares continuous tapered root canal. The purpose of this experiment was to examine the smoothness of the internal surface of prepared root canal and the effectiveness of debridement in prepared root canal by SEM for the comparison of hand and Ni-Ti rotary instrument. 25 extracted human teeth were access opened and # 10 K-type file was introduced into canal until it was appeared at the apical foramen. The working length was established by subtracting 0.5mm from this measurement. Group 1. The root canal preparation was done to # 30 with working length and then step-back until # 45 with K-Flexofile (Maillefer, Swiss). Group 2. Root canal preparation was done by Naviflex Ni-Ti file (Brasseler, USA) as the same technique with group 1. Group 3. Canal was prepared by Profile .04 (Maillefer, Swiss) taper until #30. Group 4. With use of Quantec (Tycom, USA) root canal was prepared from file number 1 to 8. In group 1 and 2, the root canal irrigant was NaOCl and the other groups, NaOCl and RC-prep (Premine Dental Products, USA) was used. The prepared teeth were notched with high-speed bur as bucco-lingual direction and fractured with chisel and mallet, then examined with SEM. Group 1 showed smooth internal surface. There were scratches mainly to the axial direction. Group 2 showed similar characteristics to those in group 1. Group 3 showed more smoother and linear cutting surface with bised scratches. Group 4 has the almost same characteristics group 3 and there was no difference in the file design. Ni-Ti rotary root canal instrument prepare the dentinal wall more smoother than hand instrument. The effectiveness of debridement was not fully affected by file design. The isthmus area and accessory canals of the root canal system were not prepared in any group. According to the result, hand and rotary type instrumentation techniques were effective in removal of major amount of tissue from root canal but it was not complete. In the direction of cutting movement there was difference between them.

• Clinical and Experimental Reproductive Medicine
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• v.7 no.1_2
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• pp.11-20
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• 1980

Hysterosalpingograms (H.S.G.) have been done for several decades to determine causative factors in female infertility. However, the H.S.G. only reverals uterine cavity and tubal patency or inpatency. The author prefers to find more details in regard to the status and condition of the female reproductive organs and their surrounding tissue as they pertain to infertility. H.S.G. in combination with laparoscopic examination reveals the following results. Preparation and method of performance of H.S.G. during laparoscopy in a healthy reproductive age women are as follows. When laparoscopy is not contraindicated, NPO is ordered with routine bowel preparation. Analgesics administered by injection prior to procedure are valium 10mgs and pethidine 50-100mgs. The radiographic procedure is the same as for any HSG technique. During laparoscopy a solution of 3 to 10 ccs. of 60% hypaque sodium is used. Fluroscopic scout films are obtained A-P and oblique views as well as a delayed check film. 1. Age distribution of primary and secondary infertility in this studies involving tubal factors was as follows: 20-29 age group showed 46% incidence and in the 30-39 age group, 50% incidence. Duration of infertility in this study group was the following: 1-2 years showed 26.7%, 3-5 years 53.8%, and 6-9 years 13.3%. 2. Indications of laparoscopic examination were as follows: Secondary infertility in 35% of the cases, obscure tubal occlusion on previous H.S.G. in 25%, unknown origin in 11.7%, and the remaining cases included pelvic pain, small masses, dysmenorrhea, and uterine anomaly. The laparoscopic examination showed clearly the reproductive organs and the surrounding tissues in the pelvic cavity. The abnormal tubal findings there revealed were tuberculous salpingitis and hydrosalpinx in 10% each, endometriosis and peritubabl adhesions in 6.7% each, biconuate uterus in 3.3%. The remaining 58.3% of the cases showed normal findings. Laparoscopic observation for possible myoma nodules, streak ovary, and peritubal adhesions was also done at this time. 3. Comparative tubal findings in combined H.S.G. and laparoscopic examination revealed the following. Bilateral tubal occlusion was present in 14% (7cases) on laparoscopic examination but on H.S.G. 38% (19 cases) were noted. However, tubal occlusion and peritubal adhesions were found in 26% (13 cases) upon laparoscopy and only 8% (4 cases) on H.S.G. examination alone. Normal pelvic findings were present in 60% (27 cases).

• Clinical and Experimental Reproductive Medicine
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• v.11 no.2
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• pp.41-49
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• 1984

It has been well known that ovarian steroids, estradiol and progesterone play an important role in the endometrial preparation for the implantation process. The present investigation was undertaken to correlate function of ovarian steroids with cAMP concentrations in uterine tissues of rat during the various stages of the preimplantation period. Rats ovariectomized on day 2 were treated with estradiol or/and progesterone on day 3 or on day 4 and cAMP concentrations in uterine tissues were determined by competitive protein - binding assay in control - and steroid treated - ovariectomized rats. The results obtained are as follows; 1. In control rats, cAMP concentrations in uterine tissues were decreased with preimplantation period proceeded whereas cAMP concentrations were increased and showed the highest levels on day 6 in ovariectomized rats. 2. In rats treated with progesterone only or progesterone with estradiol after ovariectomy, cAMP concentrations on day 6 were lower than those of ovariectomized control but higher than those of intact control rats while estradiol only treatment decreased cAMP concentrations on day 3 and day 6, compared with those from intact- and ovariectomized-controls. It is, therefore, concluded that the concentrations of cAMP in uterine tissues were lower in estrogen-treated rats than in ovariectomized rats, suggesting the involvement of cAMP in the regulation of uterine tissue differentiation.

• Journal of Periodontal and Implant Science
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• v.40 no.1
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• pp.3-10
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• 2010

Purpose: Periodontal regenerative therapies for defects created by severe periodontitis are mainly focused on bone regeneration. Although cementum regeneration needs to be better understood, it is believed to play an important role in periodontal regeneration. The first step toward a full understanding of cementum regeneration is to compare repaired cementum to pristine cementum. This study, which used histological techniques, was designed to focus on cementum regeneration and to compare pristine cementum to repaired cementum after surgical procedures with 8 and 24 week healing periods in a canine model. Methods: Buccal and lingual mucoperiosteal flaps of 10 beagle dogs were surgically reflected to create critical-sized defects. Intrabony one-wall defects, of which dimension is 4 mm width and 5 mm depth, were made at the distal aspect of mandibular second premolars and the mesial aspect of mandibular fourth premolars in the right and left jaw quadrants. Animals were sacrificed after 8 and 24 weeks post-surgery for histological specimen preparation and histometric analysis. Results: The repaired cementum was composed mostly of acellular cementum and cellular mixed fiber cementum and was thicker in the apical area than in the coronal area. The acellular cementum of the supracrestal area appeared to be amorphous. The newly formed cellular cementum was partially detached from the underlying circumpulpal dentin, which implied a weak attachment between new cementum and dentin, and this split was observed to a lesser extent in the 24 week group than in the 8 week group. The vertical height of the repaired cementum was greater in the 24 week group than in the 8 week group. Conclusions: Within the limitations of this study, we can conclude that repaired cementum after root planing was mainly acellular cementum and cementum tissue that matured to a shape similar to pristine cementum as the healing progressed from 8 to 24 weeks.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.1
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• pp.169-178
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• 1998

The crystal phases precipitated in various compositions glass of CaO-$SiO_2-P_2O_5$ system, were identified by XRD. E composition (CaO 49.4, $SiO_2\;36.8,\;P_2O_5$ 8.8 wt%) glass in which both apatite(($Ca_{10}(PO_4)_6O$ and $\beta$-wollastonite($CaSiO_3$) crystals would precipitate by heating, was selected as an experimental composition to prepare the glass ceramics with high bending strength and good bioactivity to the living bone. Glass powders of E composition were unidirectionally crystallized at $1050^{\circ}$C in the temperature-gadient furnace and the resultant glass ceramics were characterized. Bending strength of the glass ceramics was also measured. To investigate the bond forming ability between the glass ceramics and living bone tissue, soaking test of glass ceramics in simulated body fluid was carried out. Densed glass ceramics composed of apatite and $\beta$-wollastonite crystal were prepared by unidirectional crystallization under the optimum conditions. (2 0 2) plane of $\beta$-wollastonite crystals tended to grow perpendicularly to the crystallization direction. Average bending strength of this glass ceramics was 186.9 MPa, higher than that of the glass ceramics prepared by isothermal (not directional) crystallization In soaking test, a thin layer of apatite crystallite was formed on surface of the glass ceramics in 3 days. Apatite crystals formed on the glass ceramics could be act a role to make the chemical bond between the glass ceramics and living bone tissue.