• The Journal of the Korean dental association
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• v.22 no.12 s.187
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• pp.1059-1066
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• 1984

As an appraisal of Water Fluoridation Program in Chungju, fluoride content in the water of that city was examined, and 1176 K primary school children aged from 6 to 13 were surveyed on their oral hygiene status. The results were as followings: 1. Fluoride content ............ 0.8 ppm 2. dmf rate ............ 59.27% DMF rate ............ 39.46% 3. dmf t rate/index ............ 27.75%/2.40 dmf s rate/index ............ 11.91%/5.14 4. DMF T rate/index ............ 6.12%/0.93 DMF S rate/index ............ 1.65%/1.26

• The Journal of the Korean dental association
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• v.21 no.12 s.175
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• pp.979-984
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• 1983

As an appraisal of Water Fluoridation Program in Chungju, fluoride content in the water of that city was examined, and 1317 K primary school children aged from 6 to 13 were surveyed on their oral hygiene status. The results were as follows: 1. Fluoride content ....................... 0.8 ppm 2. dmfrate ..................................... 81.17% DMF rate .......................................... 38.88% 3. dmf t rate/index ................................ 29.17%/2.55 dmf s rate/index ............................... 14.33%/6.27 4. DMF T rate/index ............................. 6.32%/0.92 DMF S rate/index ............................ 1.86%/1.35

• Journal of the korean academy of Pediatric Dentistry
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• v.8 no.1
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• pp.89-102
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• 1981

1147 preschool children aged from 3 to 6 living in some farm villages in Kyungki-do were surveyed on dmf and distribution of dental caries in primary dentition. The results were as follows: 1. dmf rate ... 92.76 % boy ... 94.52 % girl ... 90.5.5 % 2. dmf t rate ... 37.07 % dmf t index ... 7.09 3. dmf s rate ... 13.74 % dmf s index ... 13.14 % 4. df t index ... 6.94 5. Each percentage of d, m & f per dmf teeth d rate ... 89.96 % m rate ... 7.24 % f rate ... 2.67 % 6. Most frequent site of dental caries in each tooth $\underline{A}$ mesial $\overline{A}$ distal $\underline{B}$ mesial $\overline{B}$ distal $\underline{C}$ distal $\overline{C}$ distal $\underline{D}$ disto-occlusal $\overline{D}$ disto-occlusal $\underline{E}$ linguo-occlusal $\overline{E}$ occlusal 7. Order of caries susceptibility $\overline{E}$ $\underline{E}$ $\overline{D}$ $\underline{D}$ $\underline{A}$ $\underline{B}$ $\overline{C}$ $\underline{C}$ $\overline{B}$ $\overline{A}$ 8. All the values in caries criteria showed a marked increae from those of 1968.

• Journal of the korean academy of Pediatric Dentistry
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• v.8 no.1
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• pp.15-19
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• 1981

As a pilot survey of Water Fluoridation in Chungju, Fluoride content in the water of that city was examined, and 1563 K primary school children aged from 7 to 13 were surveyed on their oral hygiene status. The results were as followings: 1. Fluoride content...0.1 ppm. 2. dmf rate...80.04 % DMF rate...45.17 % 3. dmf t rate/index...28.29 % / 2.18 dmf s rate/index...14.14 % / 5.44 4. DMF T rate/index...6.62 % / 1.07 DMF S rate/index...1.87 % / 1.51.

• Journal of Korean society of Dental Hygiene
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• v.2 no.1
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• pp.1-19
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• 2002

This study has been conducted with continuous dental sanitary education for primary school pupils for five years from 1997 through 2001, based on data obtained from a 97' survey on primary school pupils' recognition on dental hygiene education and their permanent dental health capacity. Following results were drawn through comparative analysis of data obtained during the survey period. Approx 70.77% of the examinees have experienced decay missing feeling (DMF) in the year 2001, suggesting a good effectiveness of dental hygiene education compared with 92.1 % of DMF rate in 1997. It has been found that pupils' knowledge and recognition on dental hygiene and management, etc were improved, as well as their eating habits and consciousness were changed. Comparative analysis of annual DMF showed that DMF rate, DMFT index, and DT rate were found to decrease every year, suggesting a improved dental health capacity. Grade level analysis revealed that DMFT index and DT rate were found to decrease every year during the survey period, suggesting pupils' dental management and consciousness were improved and changed. It has been found that DMF rate more significantly increased in a higher grade in 2001 than 1997. There was no difference in DMF rate between grades of primary school in 1997. However, in the year 2001 increment of approx 10% of DMF rate were observed in a higher grade.

• Applied Microscopy
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• v.31 no.2
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• pp.117-128
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• 2001

DMF is not a good solvent for PVA. There is no solvent-PVA interaction such as H-bonding. DMF/PVA makes a UCST system. DMF/PVA makes a gel through crystallization-induced gelation. X-ray, thermal analysis, and other experimental proofs are presented. The gelation rate was faster at low temperature. Small addition of PEG increased the rate of gelation, but urea decreased the rate. SEM showed the phase demixing process very clearly. In the early stage of gelation, only phase demixing was occurring at a low rate. Hence, no holes appear in the early stage photographs. As demixing proceeded further, the holes began to appear and the sizes became bigger. DMF phase remains many holes after vaporization and PVA phase constitute the matrix phase.

• Journal of the korean academy of Pediatric Dentistry
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• v.21 no.2
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• pp.463-468
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• 1994

The purpose of this study was evaluation of the oral health of cerebral palsied children by considering the DMFT index. The 31 cerebral palsied children(Male 20, Female 11) participated in the study, and mean age was 11.3 years. All patient were examined for determination of decayed tooth, missing tooth, filled tooth. For children with only deciduous dentition, the dmf system was used; for children with only permanent dentition, the DMF system was used; for children with mixed dentition, a combination of two systems(dmf and DMF) was used. The results were as follows: 1. In the deciduous dentition, dmft index was 11.60.(dt rate ; 83.62%, mt rate ; 12.07%, ft rate ; 4.31 %) 2. In the mixed dentition, DMFT index was 12.25 and dmft index was 10.75.(DT rate ; 90.00 %, MT rate ; 0 %, FT rate ; 10.00 %, dt rate ; 60.53 %, mt rate ; 28.95 %, ft rate ; 10.52 % ) 3. In the permanent dentition, DMFT index was 8.16.(DT rate ; 87.77 %, MT rate ; 11.51 %, FT rate ; 0.72 %)

• Advances in environmental research
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• v.7 no.1
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• pp.39-52
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• 2018

Direct membrane filtration (DMF) of wastewater has many advantages over conventional biological wastewater treatment processes. DMF is not only compact, but potentially energy efficient due to the lack of biological aeration. It also produces more biosolids that can be used to produce methane gas through anaerobic digestion. Most of ammoniacal nitrogen in wastewater is preserved in effluent and is used as fertilizer when effluent is recycled for irrigation. In this study, a technical feasibility of DMF was explored. Organic and nitrogen removal efficiencies were compared between DMF and membrane bioreactor (MBR). Despite the extremely high F/V ratio, e.g., $14.4kg\;COD/m^3/d$, DMF provided very high COD removal efficiencies at ~93%. Soluble microbial products (SMP) and extracellular polymeric substances (EPS) were less in DMF sludge, but membrane fouling rate was far greater than in MBR. The diversity of microbial community in DMF appeared very narrow based on the morphological observation using optical microscope. On the contrary, highly diverse microbial community was observed in the MBR. Microorganisms tended to form jelly globs and attach on reactor wall in DMF. FT-IR study revealed that the biological globs were structurally supported by feather-like materials made of secondary amines. Confocal laser scanning microscopy (CLSM) study showed microorganisms mainly resided on the external surface of microbial globs rather than the internal spaces.

• The Journal of the Korean dental association
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• v.23 no.11 s.198
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• pp.959-964
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• 1985

1,596 ‘H' primary school children were surveyed every year on their oral hygiene status from 1981 to 1984. The results were as followings. 1.dmft rate; 27.94%/ 28.32%/33.33%/28.98% 2.dmf index;2.51/2.90/3.21/2.93 3.dmf rate ;11.87%/11.44%/13.77%/11.26% 4.dmf index ;5.33/5.86/6.63/5.70 5.DMFT rate ;6.96%/5.00%/6.52%/6.34% 6.DMFT indes;1.07/0.67/0.90/0.86 7.DMFS rate ;2.03%/1.46%/1.98%/1.79% 8.DMFS index;1.57/0.98/1.36/1.22

• Journal of the korean academy of Pediatric Dentistry
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• v.8 no.1
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• pp.103-117
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• 1981

The data about dental caries obtained from 1438 preschool children (male 797, female 641) in Seoul aged from 3 to 6 were analyzed by their sexes, ages, jaws and teeth surfaces. The results were as follows. 1. dmf rate : 92.63% 2. dmft index : 6.06 dmft rate 30.81 % dmfs index : 11.82 dmfs rate 12.02 % 3. d,m & f rate d rate: 79.45% m rate: 8.15% f rate : 12.40 % 4. dft index : 5.94 5. The order of caries susceptible tooth 1. Lower deciduous 2nd molar 2. Lower deciduous 1st molar 3. Upper deciduous 2nd molar 4. Upper deciduous lateral incisor 5. Upper deciduous cental incisor 6. Upper deciduous lateral incisor 7. Lower deciduous canine 8. Upper deciduous canine 9. Lower deciduous central incisor 10. Lower deciduous lateral incisor 6. Predilection sites of each tooth A) Deciduous central incisor ; Max. : Mesial cavity Mand. : Mesio-distal cavity B) Decidous lateral incisor ; Max. : Mesial cavity Mand. : Distal cavity=Mesial cavity C) Deciduous canine; Max. : Labial cavity Mand. : Distal cavity D) Decidous 1st molar ; Max. : Disto-occlusal cavity Mand.: Disto-occlusal cavity E) Deciduous 2nd molar ; Max. : Linguo-occlusal cavity Mand.: Occlusal cavity 7. All the values in caries criteria in 1981 were somewhat lower than in 1968, but m & f rate were increased.