• Journal of the korean academy of Pediatric Dentistry
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• v.11 no.1
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• pp.1-6
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• 1984

The author studied the prevalence of proximal dental caries of deciduous molar by observing intraoral radiographies of 478 children aging from 2 to 5 who visited the Dep. of Pedodontics, Seoul National University Hospital. The following results were obtained; 1. The prevalence of proximal caries of deciduous molar did not show significant difference between male and female, right and left side. 2. Mandibular deciduous molar had higher prevalence than maxillary deciduous molar. 3. The prevalence was increased with age. 4. The prevalence was highest in the distal surface of lower 1st deciduous molar and lowest in the distal surface of upper 2nd deciduous molar.

• 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.

• Journal of the korean academy of Pediatric Dentistry
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• v.23 no.2
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• pp.389-400
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• 1996

In Class II amalgam restoration in deciduous molar, failure rate and incidence of recurrent caries are high as children become older. In order to preserve deciduous molars till the physiologic exfoliation time, stainless steel crown is a choice of the treatment. As a result of a careless treatment, such as overhanging margin, poor marginal adaptation, poor proximal contour and inadequate mesiodistal width give rise to interfering eruption of the adjacent teeth, recurrent caries and chronic gingival irritation and insufficient arch length respectively. In this study, 252 s.s. crowned teeth extracted due to physiologic exfoliation or periapical lesion. The purpose of this study is to analyze the marginal adaptation of stainless steel crown to the deciduous molar in order to obtain better clinical result. The results were as follows : 1. Between the length of s.s. crown and the marginal gap of crown, positive correlations were shown. 2. Largest amount of marginal gap was shown at buccal side in upper deciduous molars and lower first deciduous molar, lingual side in lower second deciduous molar. But no significant diffrence were found statistically compared to second most largest one. 3. Incidence of exposed restoration and recurrent caries were higher in proximal surface than buccal/lingual surface. And extension of restoration below the margin of s.s. crown gives rise to higher rate of recurrent caries. 4. Defect of contour was found in 34%, frequently found in lower 1st deciduous molar and upper 1st deciduous molar. 5. Marginal polishing defects were found in 23%. 6. Ledge was formed in 10% especially in lower 1st deciduous molar and lower 2nd deciduous molar. 7. 16% of the teeth had wear facet due to traumatic occlusion, 7% of them had occlusal perforation.

• Journal of the korean academy of Pediatric Dentistry
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• v.1 no.1
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• pp.19-29
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• 1974

Surveying the root resorption of the mandibular deciduous teeth in 967 children, (Male 493 Female 474) from 3 to 12 years old by orthopantomography, the author obtained the following results. 1) Female in the root resorption of the deciduous teeth was earlier than male. 2) The stages of initial resorption of the deciduous teeth were as follow. central incisor 4 years lateral incisor 4 years 2 months cuspid 6 years first decid uous molar 6 years second deciduous molar 6 years 5 months 3) The exfoliational stages ($R_5$) of the deciduous teeth were as follow. central incisor 6 years 8 months lateral incisor 7 years 2 months cuspid 9 years 10 months first deciduous molar 10 years 3 months second deciduous molar 11 years.

• The Journal of the Korean dental association
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• v.17 no.7 s.122
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• pp.525-528
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• 1979

958 healthy Korean children aged from 2 to 11 years old (male: 500 female:458) were studied on the root resorption of the mandibular first deciduous molar. The Results were as follows: 1. The resorption of mandibular first deciduous molar in female was earlier than male. 2. The patterns of the initial resorption of mandibular first deciduous molar were as follows Distal root is resorbed by the Successor ; 55.92% Both roots are resorbed by the Successor simultaneously ; 30.51% Mesial root is resorbed by successor ; 6.33% Mesial root is resorbed by the mandibular first bicuspid and canine ; 4.08% Bifurcation area is resorbed by the successor; 3.16% 3. The Exfoliation period of mandibular first deciduous molar was 10 years 1month in female and 10 years 4 months in male.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.3
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• pp.362-371
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• 2004

It is essential to have adequate knowledge of the timing of root resorption of deciduous teeth for diagnosis and treatment planning in pediatric and orthodontic dentistry. Dental development is also influenced by hereditary characteristics, environmental factors, race, sex, endocrine reaction, nutrition, socioeconomic condition and secular factor. The aims of the present study were to determine the mean age of root resorption of deciduous teeth in contemporary Korean children and to compare the mean age of root resorption time of deciduous teeth between early 1990s and early 2000s. The study population was made up of Korean children attending the pediatric dentistry ward of Kyungpook National University Hospital. One thousand thirty seven children's panoramic radiograph (girls: 528 persons, boys: 509 persons) in $1990{\sim}1992$ and one thousand sixty five children's panoramic radiograph (girls: 394 persons, boys: 671 persons) in $2001{\sim}2003$ were examined. This study utilized a cross-sectional design. Due to the problems of imaging in the maxillary region and the mandibular incisor region, the mandibular deciduous canine, the mandibular deciduous first molar and the mandibular deciduous second molar were chosen for examination. The results were as follows. 1. There is a tendency for the teeth to resort earlier in the early 2000s group than the in early 1990s group. At the Res c stage, the difference of the mean age was 0.4 years. 2. At the Res c stage, the order of difference of the mean age from smaller to larger for the girls was the mandibular deciduous canine, the mandibular first deciduous molar, and the mandibular second deciduous molar. On the other hand, for the boys, the order was the mandibular second deciduous molar, the mandibular first deciduous molar, and the mandibular deciduous canine. The difference was larger with aging in girls and smaller with aging in boys. 3. There is a tendency for the teeth to resort earlier in girls in both the early 1990s group and the early 2000s group. The difference of the mean age between girls and boys was 0.3 year. 4. The commencement of root resorption of the mandibular deciduous canine was slower than that of the mandibular first deciduous molar. However, the completion of root resorption of the mandibular deciduous canine is faster than that of the mandibular first deciduous molar. The total elapsed time of root resorption from commencement to completion was shortest in the mandibular deciduous canine. 5. For each of the teeth in the early 1990s and the early 2000s groups, the speed of root resorption was in the later stage faster than in the earlier stage. In order to know about the exact timing of root resorption of deciduous teeth, periodic and longitudinal studies preferably covering the entire period of growth, is required.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.3
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• pp.543-548
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• 1997

The first permanent molar takes important place in the occlusion. Malposition of the lower first molar is frequently due to mesial migration, which is occurred by early exfoliation of the second deciduous molar or proximal caries of deciduous teeth. Above things happen without any consideration of space maintainer, prompt measures for space regaining have to be started. Especially in the case with early loss of the second deciduous molar, it has been said that there is no suitable appliance for maintaining the space before the eruption of the permanent first molar. In distalizing the upper first molar, headgears have been routinely used, which its result was definitely depended on cooperation of the patients. Nowadays, appliances such as pendulum appliances, K-loop, magnets, which can be used without cooperation of the patients, are introduced. Jones Jig, one of the molar distalizing appliances, was used on the patients who visited department of pediatric dentistry in Seoul National University Dental Hospital complaining of no eruption space for the lower second bicuspid. Either removable splint or lingal arch was used as the anchorage. Jones Jig was favorably used in the lower molar, where vestibule is shallow, and this is a case report on the satisfactory result thereof.

• Journal of the korean academy of Pediatric Dentistry
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• v.21 no.2
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• pp.486-490
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• 1994

Maxillary first molar is the key in normal occlusion. Mesial drifting of maxillary first molar result form early loss of second deciduous molar. Mesial drifted maxillary first molar was treated by headgear, Hawley appliance with screw, brasswire, etc. But, these appliance should be necessary for patients cooperation. Recently, several appliance for molar distalizing without patients cooperation has been introduced. We are reporting in this paper about distalizing of mesial drifted maxillary first molar because of early loss of deciduous second molar by open coil jig. Distalization of molar by open coil jig is predictable, rapid, painless method without mecesscity of patient cooperation.

• Journal of the korean academy of Pediatric Dentistry
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• v.4 no.1
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• pp.39-44
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• 1977

150 "K" primary school children, from 6 to 10 years old, have been examined both clinically and radiographically for proximal caries in deciduous canine and deciduous posterior teeth and permanent first molar teeth. 1. 598 proximal cavities were diagnosed 154 (25.75%) were revealed by both examinations. 39 (6.52%) appeared on clinical examination only, but 405 (67.73%) were revealed by radiographic examination only. 2. The dental caries occurance on distal surface of first deciduous molar and mesial surface of second deciduous molar were revealed much higher values in all ages. 3. There is no significant differences observed between right and left arch. 4. Proximal cavities were revealed 1.7 times more in mandible than in maxilla.

• The korean journal of orthodontics
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• v.15 no.2
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• pp.341-352
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• 1985

The primary objective of this study is to estimate of the mesiodistal crown diameters of the unerupted permanent successors derived from the mesiodistal crown diameters of the deciduous teeth in Korean population. The subjects were 54 individuals (twenty nine boys and twenty five girls) with normal occlusion aged 6 to 13 years. The mesiodistal crown diameters of the deciduous and the successional permanent teeth were measured from the longitudinal dental cast models using the sliding calipers (Mitutoyo Co.). From the study, the results are as follows; 1. Sex differences of mesiodistal won diameters were less in the deciduous teeth, but male were more than that of female in the successional permanent teeth. 2. The mesiodistal crown diameters of the deciduous central incisors, lateral incisors, canines were smaller than that of the successional permanent teeth and the deciduous 1st molars, and 2nd molars were more larger than that of the successional permanent teeth. 3. Size differences between sum of the mesiodistal crown diameters of central incisors and lateral incisors in the decidous teeth and the successional permanent teeth were $7.20{\pm}1.79mm$ in upper, $5.38{\pm}1.64mm$ in lower and that of canine,1st molar and 2nd molar in the deciduous teeth and the successional permanent teeth were $0.56{\pm}1.19mm$ in upper, $2.22{\pm}1.19mm$ in lower. 4. In male, the correlation coefficients between the upper deciduous central incisor and the successional permanent tooth (r = 0.57) and in female, the correlation coefficients between the upper deciduous 1st molar and the successional permanent tooth (r=0.67) appeared the highest. 5. The regression constants were determined to estimate the mesiodistal crown diameters of the unerupted successional permanent teeth.