• 한국산업보건학회지
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• 제25권4호
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• pp.506-515
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• 2015

Objectives: This study was conducted to evaluate the status of hazard communication regarding dental materials among dental hygienists in the Daegu Metropolitan City and the North Gyeongsang-do Province area. Materials: A total of 310 dental hygienists were surveyed using self-administered questionnaires to investigate the status of hazard communication on dental materials and information needs. We collected instructions for use and material safety data sheets(MSDSs) for 67 dental materials frequently used at dental hospitals located in the Daegu Metropolitan City and the North Gyeongsang-do Province area. Results: The questionnaire surveys showed that only 11% of the 310 dental hygienists had knowledge of MSDS and 46.8% of respondents never read instructions for use before using materials. Just 7.4% of dental hygienists have undergone training on hazard information for dental materials. In particular, dental hygienists working at dental clinics had significantly lower response rates on knowledge of MSDS(p<0.001), reading of instructions for use(p=0.042) and training on the hazard information of dental materials(p=0.004) than those in dental hospitals or general hospitals. The essential information most desired by dental hygienists was hazard identification(82.3%) followed by first-aid measures(53.9%), handling and storage(51%), disposal considerations (49%) and toxicological information(47.1%). All dental materials were on foreign products which came from Japan(59.7%), the USA(26.9%) and Liechtenstein(13.7%). In terms of usage, 56.7% of dental materials were prosthetic, followed by conservation(31.3%), orthodontics(9%), and prevention(3%). We found that dental hygienists had accessed MSDSs for only five dental products among the 67 dental materials. The instructions for the use of the 67 dental materials provided hazard identification(64.2%), first-aid measures(83.6%), handling and storage(97%), disposal considerations(20.9%) and toxicological information(26.9%). Conclusions: Based on the results of this study, the hazard communication system for dental hygienists working at dental clinics should be improved.

• 대한치과의사협회지
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• 제55권5호
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• pp.339-350
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• 2017

The aim of the study was to analyze the distribution of dental filling materials for carious permanent teeth of school children in a city. The study was designed as time-serial study, using the data of the dental survey for children aged 8-, 10- and 12-year children living in Gimhae city. The samples were selected by stratified clusters sampling. The number of surveyed samples in depth-analysis for types of dental filling materials were 567 in 2009 and 331 in 2013, respectively. They had dental restorations on one or more teeth. The changing pattern of used dental filling materials was analyzed between 2009 and 2013. Statistical analysis was conducted according to variables related to dental filling material type; DMFT and DMFS index, number of fissure sealed teeth and surface and surveyed year. Amalgam filling rate decreased from 27.9% in 2009 to 18.8% in 2013, while filling rate of tooth-colored materials increased from 56.1% in 2009 and 68.9% in 2013. Amalgam filling rate was a negative correlation with filling rate of tooth-colored materials or gold and number of fissure sealed teeth and a positive correlation with DMFT index. Filling rate of tooth-colored materials was a negative correlation with filling rate of amalgam or gold and DMFT index and a positive correlation with number of fissure sealed teeth. The light-curing composite resin should be included in the reimbursement range of National Health Insurance to solve an inequity of dental health care services.

• 대한통합의학회지
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• 제9권3호
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• pp.79-86
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• 2021

Purpose : This study was conducted to provide fundamental data to prepare for countermeasure to protect health of workers in the dental clinics from hazardous chemical substance, and to assess effecting factors on management of Material Safety Date Sheet(MSDS) and handling of hazardous chemical substance among workers in dental clinics. Methods : This study was carried out a survey with structured self-administered questionnaire which was consisted of 7 questions about the management of MSDS, 9 questions about recognition and practice of hazardous chemical substances in dental clinics, and 7 questions about general characteristics. Total subjects of this study were 204 adult who workers in dental clinics located in Busan and Gyeng-nam province area. The collected data were analysed using the SPSS statistical package program (ver. 23.0). Results : The factor that positively affected factor on recognition and practice of hazardous chemical substances in dental clinics has experience that has been institutional health-care accreditation. The factor that positively affected the management of MSDS has experience that has been institutional health-care accreditation. Conclusion : It is necessary to prepare countermeasures such as campaign and education on cognition of general chemical substances, and also the author concern that it should be perform the education on handling of hazardous chemical substances in dental clinics for more effecting management of MSDS. In order to improve the management of MSDS and improve the awareness and safety of chemicals, it is necessary to encourage the implementation of the institutional health-care accreditation system or prepare guidelines for the management of MSDS.

• 대한치과보철학회지
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• 제27권2호
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• pp.131-141
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• 1989

This study was designed to investigate the fitness of stock tray in Korean adults. 107 dental students (male: 87, female: 20) who have normal occlusion and symmetric facial fom were selected. The upper and lower stock tray (Osungtray, Osung Co., Korea) fit with dental arch were selected for taking irreversible hydrocolloid impression. The author measured the thickness of impression material about two items, that is, width and length on the flange of stock tray. Several measuring points on the dental arches and palatal area were checked with Goldman Fox prove (Hu-Friedy, U.S.A.). The obtained results were as follows: 1. The width of impression material on buccal flange of upper and lower trays were narrower than any other measuring point, but the thickness of impression material on the palatal area of upper stock tray was the widest of all measuring points. 2. The length on buccal flange of lower stock tray was shorter, but the length on tray flange of lower stock tray at lingual frenum area was longer. 3. On upper dental arch, the upper extra-large tray was used in 53% of subjects, but upper small tray was not used. 4. On lower dental arch, the large tray was used in 55% of subjects. 5. There was not adequate tray on upper dental arch in 4 subjects.

• 대한치과기공학회지
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• 제42권2호
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• pp.149-162
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• 2020

Purpose: The purpose of this study was to conduct a cost accounting of implant prosthesis according to the fabrication activities. Methods: In this study, the cost price of implant prosthesis fabrication activities was calculated by the bottom-up costing approach for material and labor cost and the top-down costing approach for expenses and other. Results: The total cost price was estimated to 220,000 ~ 310,000 won per one implant prosthesis. By product, the screw type was estimated to 220,000 ~ 230,000 won, and when the stent and tray were included, it was 260,000 ~ 270,000 won, which increased about 40,000 won. And, the cement type with more material and labor time was estimated to 250,000 ~ 260,000 won, and when the stent and tray were included, it was about 300,000 won. Conclusion: In terms of the fabrication cost ratio by items, it was shown that material cost and labor cost accounted for about 40% and 30% of the total cost structure for resin case, respectively, which was the opposite for porcelain. It was shown that expenses and general administrative expenses accounted for about 15%, and profits were about 11% ~ 14% in both cases.

• 대한치과기공학회지
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• 제38권4호
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• pp.255-262
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• 2016

Purpose: This study examined the effect of wettability of gypsum materials and rubber impression material on the marginal fitness of zirconia copings. Methods: Three commercially available gypsum materials(Fugirock EP, Snow Rock, Tuff Rock) and three zirconia blocks(iJAM Emerald, LUXEN Smile block, ICE Zirkon transluzent) were studied. The zirconia copings were fabricated by using dental CAD/CAM system. Contact angles on the impression materials were measured with contact angle measuring device. Silicone replica method was used to measure the marginal fitness and cutting was performed on the bucco-lingual and mesio-distal sides. It were observed with a stereomicroscope at °ø40 magnification. The data were statistically analyzed with One-way ANOVA. Results: Mean values of contact angles were $58.3{\pm}0.7^{\circ}$ for Tuff Rock, $77.5{\pm}0.5^{\circ}$ for Fugirock EP and $87.8{\pm}0.5^{\circ}$ for Snow Rock and the difference between them was statistically significant(p<0.05). The smallest values of marginal fitness for the JF groups were $30.7{\pm}3.0{\mu}m$ for bucco-lingual direction, $29.3{\pm}3.0{\mu}m$ for mesio-distal direction. One-way ANOVA showed statistically significant difference between groups for marginal fitness(p<0.05). Conclusion: Tuff rock gypsum material had superior wettability to others. The mean marginal fitness of the Tuff rock gypsum material group were significantly better than other groups. Thus they can be also expected to show clinically satisfactory marginal fitness.

• 대한치과의사협회지
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• 제33권1호통권308호
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• pp.47-58
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• 1995

• 대한치과기공학회지
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• 제10권1호
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• pp.171-175
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• 1988

A good material selection and high dental techniques shall be required in all procedure from waxing up to investing of wax patten in order to get a cast restoration with good adaptability. Generally, wax and investing material should not have any deformation property but they art not so perfact in practice. Therefore, as the one of methods to produce more perfact, less deformation property and excellent product, it is necessary to eliminate the problems which can cause a deformation in each procedure.

• Journal of Oral Medicine and Pain
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• 제24권1호
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• pp.81-94
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• 1999

This study intends to find usefulness of the computer assisted dental identification in mass disaster. The variety of dental characteristics was investigated through the research of dental records of 508 adults. And a computer assisted simulation program was used to evaluate the selectivity of dental identification. Findings were as follows : 1. Combinations of dental characteristics were found 155 types. The most various dental characteristic was showed on the mandibular first molar. 99.0% of subjects had dental characteristics for dental identification. 2. The posterior teeth, in comparison with anterior teeth, showed higher selectivity in dental identification which was enhanced by information on the material, type and cavity of the restoration. 3. The variety of dental characteristics was mainly found on the combinations of missing tooth with the material, type and cavity of the restoration. 4. The computer assisted dental identification program, with informa- tion about one's tooth state, made individual identification possible when there was only a part of the teeth in a corpse. 5. The computer assisted dental identification had considerably high selectivity based on the variety of dental characteristics. And it was also performed faster and preciser than the existing identification methods. Based on the results of this study, there are various combinations of the feature of the tooth itself with dental characteristics caused by a certain type of treatment on the teeth. And using the computer assisted dental identification program based on this, dental identification can be more efficient economically and more useful than any other forensic identification methods.

• 대한치과의사협회지
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• 제15권2호
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• pp.107-110
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• 1977

Class I malocclusion is essentially a dental dysplasia. Rotations, individual tooth malpositions, missing teeth, tooth size discrepancies, etc., fall under this classification. There are two types of class I malocclusions. One is identified by and insufficient denture base to accommodate the teeth; the other has more denture base than tooth material, creating spaces in the arch. The tooth material-to denture base discrepancies may be slight, calling for only a little increase in arch length for alignment and the correction of minor rotations. Discrepancies may also be great, in which case it becomes necessary to reduce tooth material by extraction, so as to make the tooth material more in proportion to the size of the denture base. The author had attempted orthodontic treatment of a class I malocclusion case of 13-year old boy in which high canines and impacted mandibular second premolars were involved. The author obtained good results.