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Measurement of Porcine Aortic and Pulmonary Valve Geometry and Design for Implantable Tissue Valve (돼지 대동맥, 폐동맥의 근위부 기하학적 구조 측정을 통한 판막 구조 수치의 계량화와 판막 도안에 관한 연구)

  • Park, Sung-Joon;Kim, Yong-Jin;Nam, Jin-Hae;Kim, Soo-Hwan;Lee, Chang-Ha;Lim, Hong-Gook
    • Journal of Chest Surgery
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    • v.43 no.6
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    • pp.602-613
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    • 2010
  • Background: As life expectancy has been increased, the cardiac valve disease has been increased. In past, mechanical valve for valve replacement surgery was used widely, but it has many weaknesses, such as hemorrhage, teratogenic effect caused by warfarin, acute mechanical failure, taking warfarin during life, etc. So, the tissue valve is used widely and researches for durability of tissue valve are in progress. Tissue valves being used are all imported in Korea, and there is a lack of information on its geometry and design. So, we studied the geometry of porcine aortic and pulmonary valve, and tried to suggest theoretical basis for making the aortic and pulmonary valve. Material and Method: We harvested aortic and pulmonary valves of 25 pigs and measured the geometry of valve at fresh and glutaraldehyde (GA) fixed state. In each group, we measured the diameter of the base, diameter of commissure, valve height, commissural height, etc. Also, for making implantable porcine and bovine pericardial valve, we designed the valve stent form, thickness, height, and leaflet size, form, thickness by different size of valve. Result: The aortic and pulmonary valve geometry and ratio were measured in each group. The right coronary cusp of aortic valve and right facing cusp of pulmonary valve was bigger than other cusps and non coronary cusp was smaller than others (RCC: NCC : LCC=1 : 0.88 : 1). Valve height was correlated to the leaflet size. We designed the outer diameter of stented porcine aortic valve from 19 mm to 33 mm and designed stent height and width, using previous measured ratio of each structure, stent thickness, working thickness (for making valve). Also, we designed the size of stent and form for stented bovine pericardial valve, considering diameter of valve, leaflet length, height and leaflet minimum coaptation area. Conclusion: By measuring of 25 pig's aortic and pulmonary valve geometry and ratio, we can make theoretical basis for making implantable stented porcine valve and bovine pericardial valve in various size. After making implantable valve using these data, it is necessary to do in vivo and in vitro researches, furthermore.

Studies on the Effects of Amylase Addition to Rice Extrusion on the Rheological Properties of the Extrudate for Weaning Food Base (압출조리를 이용한 쌀 이유식 제조에서 아밀라제 첨가가 물성변화에 미치는 효과)

  • Lee, Gang-Gweon;Kim, Ji-Yong;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
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    • v.26 no.6
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    • pp.670-678
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    • 1994
  • The effects of amylase addition during extrusion cooking of rice on the physico-chemical properties of the extrudates were investigated in order to develop rice-based Korean style weaning food products. A laboratory-built single screw extruder was used, the enzymes used were Termamyl 120LS(amylase from Bacillus licheniformis, NOVO Co.), BAN 240L(amylase from Bacillus amylolichuefaciens, NOVO Co.) and malt powder. By the addition of enzymes, the water soluble index of the extrudates increased by 3 times compared to that of the extrudates without enzyme and the concentration of reducing sugar in the extrudates increased drastically at 28 feed moisture. The gel permeation chromatographic pattern showed that the large molecular starch fractions diminished by the addition of enzyme during extrusion and the low molecular fraction increased. The residual enzyme activity in the extrudate were 27% for the most thermo-resistance enzyme by treating at $140^{\circ}C$ in the metering section of the extruder. The sediment volume of the extrudate dispersion increased as the metering section temperature increased to $140^{\circ}C$ . By the addition of enzymes the viscosity of extrudate dispersion was redused $1/4{\sim}1/200$ of that of the extrudates without enzyme. It allowed to use 1.8 times of solid material to the weaning food formulation to attain the same level of consistency as the commercial products. It proves that the addition of amylase during rice extrusion is effective to increase the energy density of weaning food by starch degradation, which results in the increases of water solubility, reducing sugar content, dispersibility and fluidability.

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The Weathering and Chemical Composition of Young Residual Entisols in Korea (잔적 암쇄토의 화학조성과 풍화도)

  • Zhang, Yong-Seon;Jung, Pil-Kyun;Kim, Sun-Kwan;Jo, In-Sang
    • Korean Journal of Soil Science and Fertilizer
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    • v.34 no.6
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    • pp.373-379
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    • 2001
  • The weathering rates and change of chemical composition of 6 residual Entisols derived from granite, granite-gneiss, limestone, sandstone, shale, amd basalt in Korea were studied. The chemical composition of each profile with parent rocks were determined using XRF with the physico-chemical properties and the morphology of soils. In the A horizons of all the soils except Euiseong series, the content of clay, organic matter and cation exchange capacity(CEC) showed higher than those of C horizon, but bulk density and pH showed lower than C horizon. Clay content in the soil from sandstone was decrease with soil depth, which may caused by the elluriation. In total element analysis. $SiO_2$ was high in the soil from granite. granite-gneiss, sandstone and compare with basalt and limestone. $Fe_2O_3$ and MgO was high in the soil from basalt, limestone and shale compare with granite. granite-gneiss and sandstone. And ignition loss was particularly high in the soil from basalt and limestone. The rate of element loss was higher in base cations(Ca, K, Mg, Na) than Si, Al, Fe in the soils. The concentrations of $TiO_2$ in the A horizon compare with that of the C horizon was due to resulting from losses of other less stable elements existed. Considering with relative rate of each elements in soils, $SiO_2$ and $Al_2O_3$ which originated from sandstone and granite, granite-gneiss, sandstone, shale, and basalt were lost higher than those from lime tone, but loss of basic cations were more in the soil from limestone which may be rapid weathering of calcite. The magnitude of losses of the overall elements were increased in the order of the soils from sandstone and granite ${\gg}$ limestone and shale) granite-gneiss and basalt.

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Change of the Left Atrial Dimension and Transport Function after the Cox-Maze Procedure for Treating Atrial Fibrillation Associated with Mitral Valve Disease: the Short-term and Mid-Term Results (승모판막 질환과 동반된 심방세동에 대한 Cox-Maze 술식 후 좌심방 크기 및 기계적 수축력 변화: 중.단기 경과 관찰 분석)

  • Kim, Hwan-Wook;Lee, Jae-Won;Cho, Won-Chul;Jung, Sung-Ho;Choo, Suk-Jung;Song, Hyun;Chung, Cheol-Hyun
    • Journal of Chest Surgery
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    • v.42 no.3
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    • pp.317-323
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    • 2009
  • Background: Although high efficiency of conversion into sinus rhythm has been demonstrated after performing the Cox-Maze procedure in patients with atrial fibrillation associated with mitral valve disease, the changes in the mechanical function and size of the left atrium have not been determined. The aim of the study was to evaluate the effect of the Maze procedure on the left atrial size and contractile transport function. Material and Method: From July 1997 to July 2008, 647 consecutive patients were operated on for chronic atrial fibrillation associated with mitral valve disease. Among these, 211 patients that (1) were able to be followed up for 2 years after surgery, (2) had sustained normal sinus rhythm, regardless of whether they were taking anti-arrhythmic medications and (3) did not have valvular regurgitation greater than grade III or they did not have moderate grade valvular stenosis were selected for evaluation. The left atrial size and contractile transport function were assessed by transthoracic echocardiography at the postoperative base line (1 year) and at regular follow-up periods (2 years, 3 years, 4 years and 6 year). Result: The left atrial dimension was increased and the contractile transport function was decreased during the follow-up period. The longer the follow-up period, the greater was the statistical significance of the left atrial size increase and contractile transport function decrease. Conclusion: In patients who sustain normal sinus rhythm conversion after a Maze III procedure with a mitral valve operation, there is a gradual increase of the left atrial dimensions and a decrease of contractile transport function during the follow-up period. Therefore, scrupulous follow-up is needed for these patients.

A study for Beating Filter Press Dewatering Technology (열(熱) 필터프레스 기술(技術)을 통한 슬러지 탈수율(脫水率) 향상(向上)을 위한 연구(硏究))

  • Lee, Jung-Eun;Kim, Dong-Su
    • Resources Recycling
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    • v.15 no.3 s.71
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    • pp.38-45
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    • 2006
  • The thermal filter press dewatering(TFPD) technology to improve the dewaterability through increasing the inner vapor pressure, lowering the filtration viscosity and forming the porosity easily within cake as applying the heat at the sludge layer was developed in this study. The hot water with temperature of $95^{\circ}C$ and pressure of $1.2kg_f/cm^2$ was supplied to the heating plate equipped between filter plates with plate size of $470{\times}470mm$ and material of polypropylene. Sludge was dewaterd by supplying pressure of $5kg_f/cm^2$ and then by squeezing pressure of $15kg_f/cm^2$. As a results of estimating the characteristics of thermal dewatering to consider the initial water content and organic content to be influenced by a period of water shortage and rainwater, the dewatered cake water content was about 35 wt% and dewatering velocity was $4DSkg/m^2{\cdot}hr$ under the rainwater period, and the dewatered cake water content was about 50 wt% and dewatering velocity was $1.5DSkg/m^2{\cdot}hr$ in the case of sludge of water shortage season. These results was superior to the mechanical dewatering performance with water content of 70wt% and dewatering velocity of $0.9DSkg/m^2{\cdot}hr$. On the base of the results of TFPD, energy consumpted to deal with DS(Dry Solid) of 1kg was estimated by 300 kJ. It was analyzed that the energy consumption of TFPD was decreased about one third with comparison to the dryer system. Dewatering velocity of this technology was faster than the one of mechanical dewatering equipment and it was easier to product low water content cake. Therefore, this technology was recognized that dewaterability was predominant because of the fast of dewatering velocity and production of low water content cake, and also this known as economical efficiency was excellent because of low energy consumption in comparison with dryer.

Changes in Subjective/Objective Symptoms and the Light Transmissibility of Lens Associated with Overusage of Daily Disposable Circle Contact Lenses in Normal Eyes (일회용 써클소프트렌즈의 초과 착용에 의한 정상안의 자·타각적 증상 및 렌즈 광투과율의 변화)

  • Park, Mijung;Kwon, Hae Lim;Choi, Sae Ah;Kim, So Ra
    • Journal of Korean Ophthalmic Optics Society
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    • v.18 no.4
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    • pp.429-439
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    • 2013
  • Purpose: This study was assessed to investigate the change of subjective and/or objective symptoms and the light transmissibility of lens caused by over-usage of daily disposable circle contact lenses (circle lens). Methods: Three daily disposable circle lenses made of etafilcon A, hilafilcon B, and nelfilcon A were applied on 20 normal eyes free from any eye diseases by when subjects complained any kind of discomfort. On the first and the last days of lens wearing, subjective discomfort, blinking rate, non-invasive break-up time, lens centration on corneal surface and visible light transmissibility of lens were recorded at every case and compared. Results: The circle lens wearers complained discomfort when they wore the circle lens more than 15 hours, in excess of 8 hours being the recommended wearing time and the most circle lens wearers quit the lens wearing when they wore more than 30 hours. On the last day of lens wearing, the representative subjective discomforts were stiffness, dryness and tiredness. When the subjects wore circle lens more than the recommended time, a tendency of increased blinking rate and decreased NIBUT was observed when it compared with the values right after lens wearing. On the last day of lens wearing, the lens centration was shown to be decentrated from the pupil center compared with the centration right after the wearing. These changes in lens centration and blinking rate were consistently shown in all cases of lens wearing however, the difference in the degree of subjective and/or objective change was present depending on lens materials and subjects. The visible light transmissibility of circle lens has largely been changed. Conclusions: From these results, it was thought that the decreased NIBUT induced dryness and stiffness and decreased visible light transmissibility caused more blinking when daily disposable circle lens was exceedingly used, which provoked lens decentration and subjective discomfort. However, the difference of subjective and/or objective change was largely varied in accordance with the lens material types and individuality and thus it may occur some unexpected problems by the individual base. Therefore, the education about the necessity to comply with the recommended wearing time and the problem will be essential.

Promotional Strategies of Local Drugstores

  • Kim, Seung-Mi;Lee, Sang-Yoon;Kim, Pan-Jin;Kim, Nam-Myun;Youn, Myoung-Kil
    • The Journal of Industrial Distribution & Business
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    • v.1 no.1
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    • pp.5-12
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    • 2010
  • The retail business of drugstore was introduced to Korea for the first time 10 years ago. Since Olive Young introduced a retail store in the name of drugstore in 1999 for the first time in Korea, new distribution channel combining drugstore, cosmetic products and dairy products, etc has been made. At initial stage, the new distribution channel grew up slowly because of low specialty and economic stagnation. However, the three big distribution channels, that is to say, Olive Young (CJ), Watsons (GS) and W Store (Kolon Well Care), etc, were established to produce new distribution system following large-scaled discount stores as well as convenience stores. The purpose of the study is to investigate ways making Korean style drugstore be new retail business in addition to traditional markets, department stores, E-Mart and other general super markets and to examine problems preventing the drugstore from being promoted and to find out solutions. The speciality retailers that is called a category killer attacking department stores as well as marts is expanding market quickly. New consumption trend that gives priority to wellbeing is being expanded in accordance with high level of standards of living life: The drugstore is thought to be new alternative of distribution because it keeps special products. Young ladies who are main customers of drugstores respond to the trend sensitively to have more buying power that is thought to be promising. And, consumers' desire has become concrete and special. This is because consumers want not only convenient shopping but also special shopping system that is current trend. These days, so called Multi-shop and Total shop and other special shops have been recently opened. Special multi-shop has been concentrated on fashion product and miscellaneous goods so far: Health total wellbeing shop shall be popular in accordance with wellbeing trends. Drugstores can play an important role. Drugstores were opened for the first time ten years ago. In particular, Olive Young succeeded in going into the black after making efforts for a long time by many persons. Drugstores could succeed in the business owing to many persons in the past as well as customers who liked drugstores. However, drugstores once lost ways and recorded poor business results. The three drugstores, that is to say, Olive Young, Watsons making efforts to go into the black and W-Store pursuing traditional drugstore shall compete each other and make effort to satisfy customers' desire. In that way, the three drugstores can be assured of present business as well as future business. The consumers' demand trend has become special at sub-division so that drugstores that can satisfy the demand can succeed in the business. Large businesses may be more interested in the 4th generation retail business to produce good income and to have bright future. Drugstore business and market are likely to expand and develop owing to large business' participation in drugstore business. Drugstores expanded shop at Seoul and Gyeonggi-do until middle of 2000. Drugstore business at station sphere in Seoul and Gyeonggi-do that have high ratio of temporary population has low customer loyalty to have limitation on continuous growth. Since 2009, drugstores have opened new shops at local towns: From the year of 2010, drugstores need to establish multiple shop strategy by accelerating business speed and to allow customers to drop in the shop anywhere in the nation and to enter consumers' life deeply, so that they can strengthen business base definitely. Drugstores need to have price competitiveness to have multiple shop opening strategy and to satisfy consumers and to supply high quality services that is future subject to solve. And, Olive Young and Watsons that are Korean style drugstore need to keep system in order and to strengthen substance as Korean style drugstore and to expand marketing, so that they can get business outcome within 5 years that was done 10 years before and they become the 4th generation retail business. The study had difficulties at collecting material from the three drugstore because of poor cooperation. And, the author had great difficulty at collecting statistical material that was made in disorder. Further effort is needed considering such problems.

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Thermoradiotherapy in the Treatment of Locally Advanced Nonsmall Cell Lung Cancer (국소 진행된 비소세포성 폐암에서 온열 방사선 병용 치료의 효과)

  • Kay Chul Seung;Choi Ihl Bohng;Jang Jl Young;Choi Byung Ok;Kim In Ah;Shinn Kyung Sub
    • Radiation Oncology Journal
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    • v.14 no.2
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    • pp.115-122
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    • 1996
  • Purpose : To improve the treatment results of locally advanced nonsmall cell lung cancer (NSCLC) patients we treated those patients with regional hyperthermia combined with radiotherapy. And we conducted a retrospective analysis of the results. Material and Methods Thirty two nonsmall cell lung cancer Patients treated at the Department of Radiation Oncology, St. Mary's hospital, Catholic University Medical College were the base of this analysis. Fourteen patients of above them were treated with hyperthermia and radiotherapy of more than 3000 cGy in radiation dose. Radiofrequency capacitive hyperthermia was administered twice weekly immediately after radiotherapy. Total sessions of hyperthermia ranged from 3 to 13 times (mean 7.8). Eighteen patient received an external radiation therapy alone Median radiation dose was 5580 cGy (range, 3000-7000 cGy) in fraction of 180-300 cGy, 5 fractions per week. Results: The results of themoradiotherapy group (HTRT group) were compared with radiation alone group (RT group). There were no complete response (CR) and 12 Partial responses (PR) (CR rate $0\%$, response rate $85.7\%$) in HTRT group, whereas there were 2 CRs, 8 PRs and 8 no responses (CR rate $11.1\%$, response rate $55.6\%$) in RT group. There was significant differece in local response rate of the tumors between RT group and HTRT group (p < 0.05). Overall 2 rear survival rate and mean survival were $7.1\%$ and 10.5 months for HTRT group, and $0\%$ and 8.1 months for RT group. However, by the number of hyperthermia. in cases with more than or equal to 10 sessions of hyperthermia, there were significant improvement in 2 year year survival rate and mean survival ($40.0\%$ and 18.2 months) compared with those in cases with less than 10 sessions of hyperhtemia ($7.4\%$ and 7.4 months) (p < 0.05). Conclusion : Thermoradiotherapy in locally advanced NSCLC patients increased their response rate but not 2 year survival and mean survival, therefore thermoradiotherpy with enough number of hyperthermia is suggested that may be one of the effective palliative treatments of those patients. And in cases with more than 10 sessions of hyperthermia, there showed improved 2 year survival rate and mean survival But the number of the cases was small further study in this aspect is required.

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Surgical Treatment for T4 Non-small Cell Lung Cancer Invading Mediastinal Structures (종격동 구조물을 침범한 T4 비소세포폐암의 수술적 치료)

  • 황은구;이해원;정진행;박종호;조재일;심영목;백희종
    • Journal of Chest Surgery
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    • v.37 no.4
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    • pp.349-355
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    • 2004
  • Non-small cell lung cancer (NSCLC) with invasion of mediastinal structures is classified as stage IIIB, and has been considered surgically unresectable However, in a selected group of these patients, better results after surgical resection compared to non-surgical group have been reported. The aim of this study is to evaluate the role of surgical resection in treatment of mediastinal T4 NSCLC. Material and Method: Among 1067 patients who underwent surgical intervention for non-small cell lung cancer from Aug 1987 to Dec 2001 in Korea cancer center hospital, 82 patients had an invasion of T4 mediastinal structures (7.7%). Resection was possible in 63patients (63/82 resectability 76.8%). Their medical records in Data Base were reviewed, and they were followed up completely until Jun 2002. Surgical results and prognostic factors of NSCLC invading mediastinal structures were evaluated retrospectively. Result Lung cancer was resected completely in 52 patients (63.4%, 52/82). Lung resection was lobectomy (or more) in 14, pneumonectomy in 49. The mediastinal structures invaded by primary tumor were great vessel (61.9%), heart (19%), vagus nerve (9.5%), esophagus (7.9%), and vertebral body (7.9%). Nodal status was N0 in 11, N1 in 24, and N2 in 28 (44.4%). Neoadjuvant therapy was done in 6 (9.5%, 5 chemotherapy, 1 radiotherapy), and adjuvant therapy was added in 44 (69.8%, 15 chemotherapy, 29 radiotherapy) in resection group (n=63). Complication was occurred in 23 (31.7%), and operative mortality was 9.5% in resection group. Median and 5 year overall survival including operative mortality was 18.1 months and 21.7% in resection group (n=63), 6.2months and 0% in exploration only group (n=19, p=.001), 39 months and 32.9% in N2 (-) resection group (n=35), and 8.8 months and 8.6% in N2 (+) resection group (n=28, p=.007). The difference of overall survival by mediastinal structure was not significant. Conclusion: The operative risk of NSCLC invading mediastinal structures was high but acceptable, and long-term result of resection was favorable in selected group. Aggressive resection is recommended in well selected pateints with good performace and especially N2 (-) NSCLC with mediastinal invasion.

The effect of copper alloy scaler tip on the surface roughness of dental implant and restorative materials (구리 합금 초음파 스케일러 팁이 치과 임플란트 및 수복 재료 표면에 미치는 영향)

  • Lee, Ah-Reum;Chung, Chung-Hoon;Jung, Gyu-Un;Pang, Eun-Kyoung
    • The Journal of Korean Academy of Prosthodontics
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    • v.52 no.3
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    • pp.177-185
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    • 2014
  • Purpose: This study is designed to investigate the various impacts of different types of scaler tips such as cooper alloy base tip and the others on the surface roughness of teeth and implant by the method which is currently in clinical use. Materials and methods: Four different types of disc shaped porcelain, titanium, zirconia, and Type III gold alloy dental materials sized 15 mm diameter, 1.5 mm thickness were used for the experiment. Plastic hand curette (Group PS), cooper alloy new tip (Group IS), and stainless steel tip (Group SS) were used as testing appliances. A total of 64 specimens were used for this study; Four specimens for each material and appliance group. Surface roughness was formed with 15 degree angle in ultrasonic scaler tip and with 45 degree angle in hand curette of instrument tip and the specimen surface with 5 mm long, one horizontal-reciprocating motion per second for 30 seconds by 40 g force. To survey the surface roughness of each specimen, a field emission scanning electron microscope, an atomic force microscope, and a surface profiler were used. (Ra, ${\mu}m$). Results: According to SEM, most increased surface roughness was observed in SS group while IS groups had minimal roughness change. Measurement by atomic force microscope presented that the surface roughness of SS group was significantly greater than those of PS, IS and control groups in the type III gold alloy group (P<.05). IS group showed lesser surface roughness changes compared to SS group in porcelain and gold alloy group (P<.05). According to surface profiler, surface roughness of SS group showed greater than those of PS, IS and control groups and IS group showed lesser than those of SS group in all specimen groups. Type III gold alloy group had large changes on surface roughness than those of porcelain, titanium, zirconia (P<.05). Conclusion: The result of this study showed that newly developed copper alloy scaler tip can cause minimal roughness impacts on the surface of implant and dental materials; therefore this may be a useful alternative for prophylaxis of implant and restored teeth.