• Title/Summary/Keyword: brand analysis

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Questions and Answers about the Humidifier Disinfectant Disaster as of February 2017 (가습기살균제 참사의 진행과 교훈(Q&A))

  • Choi, Yeyong
    • Journal of Environmental Health Sciences
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    • v.43 no.1
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    • pp.1-22
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    • 2017
  • 'The worstest environment disaster', 'World's first biocide massacre', 'Home-based Sewol ferry disaster' are all phrases attached to the recent humidifier disinfectant disaster. In the spring of 2011, four of 8 pregnant women including 1 adult man passed away at a university hospital in Seoul due to breathing failure. Epidemiologic investigation conducted by the Korean CDC soon revealed the inhalation of humidifier disinfectant, which had been widely used in Korea during the winter, to be responsible for the disease. As well as lung fibrosis hardening of the lungs, other diseases including asthma, rhinitis, skin disease, liver disease, fetal disease or cancers have been researched for their relation with exposure to the products. By February 9, 2017, 5,342 cases had registered for health problems and 1,131 of them were already dead (20.8% mortality rate). Based on studies by government agencies and a telephone survey of the general population by Seoul National University and civic groups, around 20% of the general public of Korea has used these products. Since the market release of the first product by SK Chemical in 1994, over 7.1 million items from around 20 brands were sold up to 2011. Most of the products were manufactured by well-known large conglomerates such as SK, Lotte, Samsung, Shinsegye, LG, and GS, as well as some European companies including UK-based Reckitt Benckiser and TESCO, the German firm Henkel, the Danish firm KeTox, and an Irish company. Even though this disaster was unveiled in 2011 by the Korean government, the issue of the victims was neglected for over five years. In 2016, an unexpected but intensive investigation by prosecutors found that Reckitt Benckiser manipulated and concealed animal tests for its own brand and brought several university experts and company employees to court. The matter was an intense social issue in Korea from May to June with a surge in media coverage. The prosecutor's investigation and a nationwide boycott campaign organized by victims and environmental groups against Reckitt Benckiser, whose product had been used by more than 70% of victims, led to the producer's official apology and a compensation scheme. A legislative investigation organized after the April 2016 national election revealed the producers' faults and the government's responsibility, but failed to meet expectations. A special law for the victims passed the National Assembly in January 2017 and a punitive system together with a massive environmental epidemiology investigation are expected to be the only solutions for this tragedy. Sciences of medicine, toxicology and environmental health have provided decisive evidence so far, but for the remaining problems the perspectives of social sciences such as sociology and jurisprudence are highly necessary, similar to with the Minamata disease and Wonjin Rayon events. It may not be easy to follow this issue using unfamiliar terminology from medical and chemical science and the long, complicated history of the event. For these reasons the author has attempted to write this article in a question and answer format to render it easier to follow. The 17 questions are: Q1 What is humidifier disinfectant? Q2 What kind of health problems are caused by humidifier disinfectant? Q3 How many victims are there? Q4 What is the analysis of the 1,112 cases of death? Q5 What is the problem with the government's diagnostic criteria and the solution? Q6 Who made what brands? Q7 Has there been a recall? What is still on sale? Q8 Was safety not checked by any producers? Q9 What are the government's responsibilities? Q10 Is it true that these products were sold only in Korea? Q11 Why and how was it unveiled only in 2011 after 17 years of sales? Q12 What delayed the resolution of the victim issue? Q13 What is the background of the prosecutor's investigation in early 2016? Q14 Is it possible to report new victim cases without evidence of product purchase? Q15 What is happening with the victim issue? Q16 How does it compare with the cases of Minamata disease and Wonjin Rayon? Q17 Are there prevention measures and lessons?

Marketing Standardization and Firm Performance in International E.Commerce (국제전자상무중적영소표준화화공사표현(国际电子商务中的营销标准化和公司表现))

  • Fritz, Wolfgang;Dees, Heiko
    • Journal of Global Scholars of Marketing Science
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    • v.19 no.3
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    • pp.37-48
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    • 2009
  • The standardization of marketing has been one of the most focused research topics in international marketing. The term "global marketing" was often used to mean an internationally standardized marketing strategy based on similarities between foreign markets. Marketing standardization was discussed only within the context of traditional physical marketplaces. Since then, the digital "marketspace" of the Internet had emerged in the 90's, and it became one of the most important drivers of the globalization process opening new opportunities for the standardization of global marketing activities. On the other hand, the opinion that a greater adoption of the Internet by customers may lead to a higher degree of customization and differentiation of products rather than standardization is also quite popular. Considering this disagreement, it is notable that comprehensive studies which focus upon the marketing standardization especially in the context of global e-commerce are missing to a high degree. On this background, the two basic research questions being addressed in this study are: (1) To what extent do companies standardize their marketing in international e-commerce? (2) Is there an impact of marketing standardization on the performance (or success) of these companies? Following research hypotheses were generated based upon literature review: H 1: Internationally engaged e-commerce firms show a growing readiness for marketing standardization. H 2: Marketing standardization exerts positive effects on the success of companies in international e-commerce. H 3: In international e-commerce, marketing mix standardization exerts a stronger positive effect on the economic as well as the non-economic success of companies than marketing process standardization. H 4: The higher the non-economic success in international e-commerce firms, the higher the economic success. The data for this research were obtained from a questionnaire survey conducted from February to April 2005. The international e-commerce companies of various industries in Germany and all subsidiaries or headquarters of foreign e-commerce companies based in Germany were included in the survey. 118 out of 801 companies responded to the questionnaire. For structural equation modelling (SEM), the Partial-Least. Squares (PLS) approach in the version PLS-Graph 3.0 was applied (Chin 1998a; 2001). All of four research hypotheses were supported by result of data analysis. The results show that companies engaged in international e-commerce standardize in particular brand name, web page design, product positioning, and the product program to a high degree. The companies intend to intensify their efforts for marketing mix standardization in the future. In addition they want to standardize their marketing processes also to a higher degree, especially within the range of information systems, corporate language and online marketing control procedures. In this study, marketing standardization exerts a positive overall impact on company performance in international e-commerce. Standardization of marketing mix exerts a stronger positive impact on the non-economic success than standardization of marketing processes, which in turn contributes slightly stronger to the economic success. Furthermore, our findings give clear support to the assumption that the non-economic success is highly relevant to the economic success of the firm in international e-commerce. The empirical findings indicate that marketing standardization is relevant to the companies' success in international e-commerce. But marketing mix and marketing process standardization contribute to the firms' economic and non-economic success in different ways. The findings indicate that companies do standardize numerous elements of their marketing mix on the Internet. This practice is in part contrary to the popular concept of a "differentiated standardization" which argues that some elements of the marketing mix should be adapted locally and others should be standardized internationally. Furthermore, the findings suggest that the overall standardization of marketing -rather than the standardization of one particular marketing mix element - is what brings about a positive overall impact on success.

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Analysis of the Domestic Consumer's Preference and Consumption Behaviors on Pork (국내 소비자의 돼지고기 선호도와 소비행태 분석)

  • Kim, Gye-Woong;Kim, Seok-Eun
    • Journal of Animal Science and Technology
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    • v.51 no.1
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    • pp.81-90
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    • 2009
  • This study was carried out to investigate consumer's preference and purchase behavior of pork including perception of brand-pork in Korea. A total of 504 respondents were surveyed and collected from December, 2007 to February, 2008. Among total respondents, 62.55% (n=314) responded that they liked the pork and respondents who were higher education level showed higher preference (p<0.05). Majority of consumers (61.16%) did not like imported pork. In addition, one who had lower education level and living in rural area disliked more the imported pork. Most consumers preferred to the belly (58.57%) and results indicated that the people who were higher education level preferred a discount mart but who were living in rural area preferred a butcher's shop. Among the purchasing area, a big discount mart was the most preferred (44.64%) and this was also different among the education level (p<0.001) and living areas (p<0.05). The consumers preferred to purchasing a 600 g pack for a single purchase. Among total respondents, 42.71% of consumers responded that their priority was reliability of meat quality on choosing the place for purchasing the pork, and the significant difference was highly found in living area groups (p<0.001). The perception of carcass grading system was common scores with the average of 2.79, and there was highly significant difference among education level groups (p<0.001). The average of 3.50 among 5 points for branded pork were evaluated by a total of consumers but the significant differences were not found in all three groups.

A Study on the Determinants of Luxuriousness: With Focus on Corporate Attributes and Luxuriousness (명품성의 결정요인에 관한 연구: 기업속성과 명품성을 중심으로)

  • Lim, JoongSik;Koh, InKon
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.11 no.4
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    • pp.191-203
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    • 2016
  • This purpose of this study is to academically define what "luxury products" mean, and to clarify the cognitive structural relationship between corporate attributes and "luxuriousness" in relation to the determinant of luxuriousness that eventually affects the purchase intention of consumers. This study is also written under the theory that luxuriousness leads to benefits such as functional benefit, experiential benefit, symbolic benefit, and exclusive benefit; which all provide core values to consumers and serve as effect factors that influence the psychological satisfaction of consumers. The commonly discussed measure of the determinant of luxuriousness has often failed to adequately describe the reasons to why the consumers prefer luxury products. This study also aims to suggest a new path in how and what the consumers perceive as luxury products, and to conceptualize what luxuriousness means in the marketing perspectives on the background of a previous theory. The part of corporate attributes are divided in the following sections: corporate ability(CA) and corporate reputation(CR). The part of the determinant of luxuriousness is divided in sections of superiority, scarcity, differentiation, and traditionality. Therefore, this study used the theoretical concept used in such common measures as well as 282 examples to empirically analyze the relationship between corporate attributes and luxuriousness of luxury products, and how such affect the purchase intentions of consumers. The survey used to aid this study targeted luxury product consumers regarding "B" brand of automobiles. Using the analysis through a structural equation model, the study draws a conclusion that in a relationship between corporate attributes and luxuriousness, corporate ability(CA) of corporate attributes affects the facts of differentiation and traditionality in a significant way, and corporate reputation(CR) of corporate attributes affects the factors of superiority and scarcity in a significant way. Additionally, the superiority and scarcity of luxuriousness positive significantly affects purchase intention, and differentiation and traditionality of luxuriousness affects purchase intention in a negative significant way. The structural concept of luxury and luxuriousness suggested in the study will provide the theoretical basis for building a new case study, and the determinants of luxuriousness in the marketing perspective will be a practical help for checking the consumers' psychological reasons for purchase.

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An alternative way of Animation Industry : Focusing on Avatar sevice's Lock-in Effect (애니메이션 산업의 대안적 연구 - 아바타 서비스의 소비자 고착화(lock-in) 전략을 중심으로)

  • Han, Chang-Wan
    • Cartoon and Animation Studies
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    • s.6
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    • pp.152-171
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    • 2002
  • This study analyses the avatar service, which is recognized as an alternative strategy of animation industry. The research questions of this study are following: (1) How have the avatar services been developed and what are the present dominant types? (2) Which structural characteristics of e-business environment are needed for the success of avatar services? (3) What is the economic characteristics of avatar business model? To solve these research questions, the basic conditions and the structural characteristics of avatar services have been investigated. In the first place, two forms of avatar service are classified. One is the internet service site whole primary service is to provide chatting service based on avatar service. The other is the portal site in which many kinds of products and services are presented as bundles to meet the needs of internet users. So avatar service is one of bundles which those portal sites are providing with. In this study, the big five internet service sites are selected based on the profits they earned through the sales of avatar service. The result of analysis is that the pricing strategy of those big five sites is very different from those of traditional off-line markets. The pricing mechanism are based on the value which internet users endow with the avatar items, not based on the costs of making the products. Avatar is the representative informative goods. The informative goods have the original cost structures, constant fixed costs and zero marginal costs, so the providers of avatar services make much of the subjective values of consumers. The sayclub, which is the most successful avatar service site and earn the average sales of 3 billing won a month, takes the aggressive strategy of pricing avatar items at highest price in the industry. The avatar service providers which make lots of profits are planning of making differentiate the services, introducing well-known brand items and star-named items. Nevertheless, the fact that the members of the sayclub are not decreasing means that the network effect of the site is so strongly manifest. Moreover, the costs the members have paid for the avatar items are so big not as to switch from one site to the other site, it can be very costly. These switching costs are endemic in high-technology industries and digital contents industries. It can be so large that switching suppliers is virtually unthinkable, a situation known as 'lock-in'. When switching costs are substantial, competition can be intense to attract new customers, since, one they are locked in, they can be a substantial source of profit. The consumers of avatar items have switching costs if they subscribe for the new avatar service site. The switching costs can be subscription costs as well as the costs of giving up the items they already paid for. One common example of switching costs involves specialized supplies, as with inkjet printer cartridges. In this example, the switching cost is the purchase of a new printer. The market is competitive ex ante, but since cartridges are incompatible, it is monopolized dx post. So the providers of printer/cartridges set pricing printer so cheap and cartridges expensive. On the contrary, since the avatar service can be successful with the strong network effect, the providers of avatar services have to compete aggressively for new customers. So they allow the subscription at a low price(almost marginal cost) in the early market. The network effect can be maximized when the members are sufficiently growing. The providers which have the monopoly power with sufficient subscribers. begin to raise the prices over the lifetime of the product and make profits.

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A Study on Food Service Franchise Location Factors and Quality of Service Factors, The Impact on Customer Satisfaction (외식 프랜차이즈 입지요건과 서비스 품질 요인이 고객만족에 미치는 영향)

  • Kim, Jo In Seog;Cho, Kyu Youn;An, Sang
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.11 no.5
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    • pp.77-90
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    • 2016
  • This study is to examine the importance of site selection and service quality in franchise business as food service franchise became one of the fastest-growing service industries today. The chief finding of this study is as follows: First, a survey in locational and service quality factors affecting food service franchise shows that responders are more concerned with hygiene and visibility of the store than proximity and transportation advantages which reflects low statistical significance, thus the distance did not seem to be a big problem for the responders in the context that they mostly visit nearby food franchise. Second, the examination of the influence by the service quality factors and customer satisfaction shows significant positive relation with customer response, speed and accuracy, and accuracy factors which reveals that the responders prefer prompt response and swift judgment toward the customer's needs and expectations, professional knowledge services to the credibility factors in which little correlation with the customer satisfaction were found. Third, the examination of the influence by the service quality factors, locational factors, and re-visit reveals that customer response and specialty showed statistically significant correlation with intention of WOM (Word of Mouth) and revisit, which suggests that swift judgment and response toward the customer's needs and expectations, professional knowledge services is of great importance to both customer satisfaction and revisit. The study on the aspects of locational and service quality factors affecting franchise industry's customer satisfaction was conducted as above, an investigation in both factors' influence on the customer satisfaction was made, and based on the results of the analysis, this research seeks an optimal operation strategy of a franchise business. Food service franchise are relatively very competent to business adminstration and reaction capability to consumption changes due to the already established market, and there are stores springing up everywhere inspired by the founders who are too confident of their success in the franchise business. However, it is necessary for the franchise beginners to figure out a zone oriented, regular customer oriented business strategy than just complying with the head office manual. Owing to an increasing trend of opening medium to large sized stores and investments in the wake of converting to multiple business type Korean food franchise, there is growing need to set up new concept of store development and operational management strategy in order to overcome the excessive competition and limited sales volume of the old-fashioned small sized, small capital franchise stores. Furthermore, as most business category of food service franchise serve very similar menus, from a product differentiation point of view, it is required to map out flexible sales concept including the adoption of competitive and low-price strategy. In conclusion, as is shown in the analytical research, the customers' optimal choice fluctuate over their preferences like customer convenience and circumstances rather than insisting on specific brand, thus it will be necessary for the franchise stores to draw up aggressive strategy and planning in running food service franchise to maximize their profits.

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CHEMICAL DEGRADATION OF LIGHT-CURED DENTAL COMPOSITE RESINS (수종 치과용 광중합형 복합레진의 화학적 분해)

  • Yang, Kuy-Ho;Choi, Nam-Ki;Park, Mi-Ran;Park, Eun-Hae
    • Journal of the korean academy of Pediatric Dentistry
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    • v.28 no.3
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    • pp.403-411
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    • 2001
  • The aim of this study was to evaluate the resistance to degradation of four commercial composite resins in an alkaline solution. The brands studied were Unifil(GC, Japan), Palfique(Tokuyama Japan). Definite$Degussa-H\ddot{u}ls$ AG, Germany). Revolution(Kerr, U.S.A.). Preweighed discs of each brand were exposed 0.1N NaOH solution at $60^{\circ}C$. After 14 days they were removed, neutralized with HCl, washed with water and dried. Resistance to degradation was evaluated on the basis of following parameters: (a) mass loss(%) - determined from pre-and post-exposed specimen weights; (b) Si loss(ppm) - obtained from ICP-AE analysis of solution exposed to specimens; and (c) degradation depth$({\mu}m)$ - measured microscopically (SEM) from polished circular sections of exposed specimens. The results were follows: 1. The mass loss of Unifil was 3.21%, it was the highest of materials. But, there was no significant difference among the materials. 2. The degree of degradation layer depth was $107.69\sim47.40{\mu}m$, the sequence of the degree pf degradation layer depth was in descending order by Unifil, Palfique, Revolution, Definite. There was significant difference among the materials except Palfique and Definite. 3. The Si loss of Paltique was 8940.0ppm, it was the highest. There was significant difference among the materials, except Revolution and Definite(p<0.05). 4. The correlation coefficient between mass loss and degradation depth was relatively high(r = 0.06, p<0.05). 5. There was no significant coefficient correlation between Si loss and mass loss, and/or the degree of degradation layer depth and Si loss. 6. When observed with SEM, destruction of bonding is observed between resin matrix and filler. Above results suggested that the hydrolytic degradation is considered as evaluation factor of composite resins.

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Investigating the Influence of Perceived Usefulness and Self-Efficacy on Online WOM Adoption Based on Cognitive Dissonance Theory: Stick to Your Own Preference VS. Follow What Others Said (온라인 구전정보 수용자의 지각된 정보유용성과 자기효능감이 구전정보 수용의도에 미치는 영향에 관한 연구: 의견고수와 구전수용의 비교)

  • Lee, Jung Hyun;Park, Joo Seok;Kim, Hyun Mo;Park, Jae Hong
    • Asia pacific journal of information systems
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    • v.23 no.3
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    • pp.131-154
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    • 2013
  • New internet technologies have created a revolutionary new platform which allows consumers to make decision about product price and quality quickly and provides information about themselves through the transcript of online reviews. By expressing their feelings toward products or services on virtual opinion platforms, users extend their influence into cyberspace as electronic word-of-mouth (e-WOM). Existing research indicates that an impact of eWOM on the consumer decision process is influential. For both academic researchers and practitioners, investigating this phenomenon of information sharing in online website is essential given the increasing number of consumers using them as sources of purchase decisions. It is worthwhile to examine the extent to which opinion seekers are willing to accept and adopt online reviews and which factors encourage adoption. Discerning the most motivating aspects of information adoption in particular, could help electronic marketers better promote their brand and presence on the internet. The objectives of this study are to investigate how online WOM influences a persons' purchase decision by discovering which factors encourage information adoption. Especially focused on the self-efficacy, this research investigates how self-efficacy affects on information usefulness and adoption of online information. Although people are exposed to same review or comment about product or service, some accept the reviews while others do not. We notice that accepting online reviews mainly depends on the person's preference or personal characteristics. This study empirically examines this issue by using cognitive dissonance theory. Specifically, in the movie industry, we address few questions-is always positive WOM generating positive effect? What if the movie isn't the person's favorite genre? What if the person who is very self-assertive so doesn't take other's opinion easily? In these cases of cognitive dissonance, is always WOM generating same result? While many studies have focused on one direct of WOM which indicates positive (or negative) informative reviews or comments generate positive (or negative) results and more (or less) profits, this study investigates not only directional properties of WOM but also how people change their opinion towards product or service positive to negative, negative to positive through the online WOM. An experiment was conducted quantitatively by using a sample of 168 users who have experience within the online movie review site, 'Naver Movie'. Users were required to complete a survey regarding reviews and comments taken from the real movie page. The data reflected user's perceptions of online WOM information that determined users' adoption level. Analysis results provide empirical support for the proposed theoretical perspective. When user can't agree with the opinion of online WOM information, in other words, when cognitive dissonance between online WOM information and users' preference occurs, perceived self-efficacy significantly decreases customers' perception of usefulness. And this perception of usefulness plays an important role in determining users' intention to adopt online WOM information. Most of researches have been concentrated on characteristics of online WOM itself such as quality or vividness of information, credibility of source and direction of online WOM, etc. for describing effect of online WOM, but our results suggest that users' personal character (e.g., self-efficacy) plays decisive role for acceptance of online WOM information. Higher self-efficacy means lower possibility to accept the information that represents counter opinion because of cognitive dissonance, whereas the people that have lower self-efficacy are willing to accept the online WOM information as true and refer to purchase decision. This study suggests a model for understanding role of direction of online WOM information. Also, our result implicates the importance of online review supervision and personalized information service by confirming switching opinion negative to positive is more difficult than positive to negative through the online WOM information. This implication would help marketers to manage online reviews of their products or services.

A Study on the Use of Dentifrice among Infants and Preschoolers (영유아의 세치제 사용에 관한 연구)

  • Chun, Ju-Yeon;Kang, Yung-Hee;Lee, Kyeong-Hee
    • Journal of dental hygiene science
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    • v.8 no.4
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    • pp.267-274
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    • 2008
  • The purpose of this study was to examine the use of dentifrice among children in a bid to provide information on dentifrice including its function to children's parents, the major consumers of dentifrice for child. And it's additionally meant to offer useful information on the production of toothpaste for kid. The subjects in this study were parents with children, who dwelled in Seoul and Gyeonggi province. After a self-administered survey was conducted for about three months from May to July 2007 to gather data on their use of dentifrice for child, a comparative analysis was implemented. The findings of the study were as follows: 1. Concerning the state of the use of their children's dentifrice, the largest number of the children(58.1%) started to use toothpaste at the age of one or down, and the most common first toothpaste they used was dentifrice for preschooler(86.8%). As for whether to use fluoride-containing toothpaste, the largest group of the parents(58.1%) gave an affirmative answer. Regarding the form of the toothpaste in use, the majority of their children used toothpaste of cream type(86.2%). The greatest group of the children used the amount of toothpaste that was as large as the three-tenths or four-tenths of the bristles(35.9%). 2. As for the state of the use of dentifrice for kid, the greatest group used that kind of toothpaste(81.4%). In the event of those who didn't use it, the last time when their children used toothpaste for kid was when they were at the western age of 3(33.9%) and 4(33.9%). Concerning the reason why they replaced toothpaste for kid with one for adult, the largest group of the parents did that on their own judgment(58.1%). As to the right time for replacing toothpaste for kid by one for adult, the greatest group considered it advisable for children to start using toothpaste for adult at the western age of 4 or 5(43.2%). 3. In relation to the state of the purchase of toothpaste for their children, the largest group was under the moderate influence of the children when they bought it(45.2%). The greatest group attached importance to the ingredients of toothpaste(41.6%), and the most preferred ingredient was fluoride(56.3%). 53.0 percent took consideration on the content of ingredients or the instructions. 4. In regard to priorities for the choice of toothpaste for their children, they gave top priority to brand(16.7%), followed by quality(14.6%) and ingredients(13.5%). The age of the parents made a statistically significant difference to the children's age when they started using toothpaste, and how they started to do that and whether they used fluoride-containing toothpaste were statistically significantly different according to that as well(p < 0.01). In regard to the impact of the occupation of the parents, the use of fluoride-containing toothpaste was more common among the stay-at-home mothers(p < 0.01).

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HYDROLYTIC DEGRADATION OF POSTERIOR RESIN RESTORATIVE MATERIALS (구치부 레진 수복 재료의 가수분해)

  • Yang, Kuy-Ho;Park, Mi-Ran;Choi, Nam-Ki;Park, Eun-Hae
    • Journal of the korean academy of Pediatric Dentistry
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    • v.28 no.4
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    • pp.673-682
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    • 2001
  • The use of resin composites has continued to increase over the last several years. In spite of their growing popularity, composites continue to exhibit a number of undesirable characteristics. One of the major deficiencies of composite restorative resins is their inadequate resistance to wear. Of the multitude of factors that have been associated with wear, subsurface degradation within the restoration is considered to be one. The aim of this study was to evaluate the resistance to degradation of four commercial composite resins in an alkaline solution. This solution with a high concentration of hydroxyl ions is a convenient medium for accelerated degradation of silane coupling and filler particles. The brands studies were Definite($Degussa-H\ddot{u}ls$ AG, Germany), Prodigy(Kerr, USA), Pyramid(Bisco, USA) and Synergy(Coltene, Swiss). Preweighed discs of each brand were exposed to 0.1N NaOH solution at $60^{\circ}C$. After 14 days they were removed, neutralized with HCl, washed with water and dried. Resistance to degradation was evaluated on the basis of following parameters : (a) mass loss(%)-determined from pre-and post-exposed specimen weights : (b) Si loss(ppm)-obtained from ICP-AE analysis of solution exposed to specimens; and (c) degradation $depth({\mu}m)$-measured microscopically (SEM) from polished circular sections of exposed specimens. The results were follows: 1. Mass loss of Synergy was $1.24{\pm}0.002%$, it was the highest, there was no significant difference among the materials. 2. The degree of degradation layer depth of Synergy was $107.83{\pm}2.52{\mu}m$, it was the highest, there was no significant difference among any other materials than Synergy. 3. There was no difference among the four materials in Si loss. 4. The correlation coefficient between mass loss and degradation depth was relatively high(r=0.06, p<0.05). 5. There was no coefficient correlation between Si loss and mass loss, the degree of degradation layer depth and Si loss. 6. When observed with SEM, destruction of bonding is observed between resin matrix and filler.

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