• Journal of the korean academy of Pediatric Dentistry
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• v.7 no.1
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• pp.53-61
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• 1980

The purpose of this study was to statistically evaluate the spacing of primary dentition according to whether or not a space existed and measurement of amount of space in 205 children (male 114, female 91) from 2 to 6 years of age. The results were as follows; 1. In the incidence of interdental space on each region, spacing between the primary lateral incisors and primary canine in maxilla and between the primary canine and 1st primary molar in mandible showed the highest percentage, on the other hand, spacing between the 1st and 2nd primary molars in both jaw showed the lowest percentage. 2. In the kinds of interdental space, the state of primate space and other space together showed the highest percentage, and in the degree of spacing, $S_2$ showed the highest percentage in both jaw. 3. In the incidence of primate space, maxillary primate space showed higher percentage than mandibular primate space in bilateral case. 4. In the type of arch form, spaced arch showed higher percentage than closed arch and about the half of closed arch showed crowding. 5. In both Jaw, available space showed incisor segments, canine segments, and premolar segments in order of amount, and there were not statistically significant differences of sex or jaws in the amount of available space.

• The Journal of the Korean dental association
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• v.10 no.6
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• pp.347-349
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• 1972

The authors selected fifty children aged 2 to 4 years who had normal occlusion from the patients admitted at the Pedodontic Department in the Infirmary of Dental College, S.N.U. Study casts were taken and observed on the primate spaces and terminal planes which are characteristics of primary dentition. The results were as follows: 1. The percentages of terminal planes were 56%±7.02 in mesial step type, 38.0%±6.86 in straight step type, 6.0%±3.36 in distal step type, respectively. 2. The percentages of primate space were 80%±5.09 in maxillary dental arch and 5.0%±7.06 in mandibular dental arch. 3. The percentage of mesial step type in korean children was higher in comparison with that in foreign children and the percentage of the primate space was about the same in korean & foreign children.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.4
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• pp.397-402
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• 2017

The aim of this study was to assess the spacing and crowding of the anterior teeth in the primary dentition in Hwaseong city. Photographs of the anterior segment of 237 children satisfied the criteria. The presence of primate spaces and developmental spaces was assessed by the proximal contacts. Physiologic spacing was observed in 47.3% and 38.0% of the cases in the upper and lower arches, respectively. 43.5% showed the presence of two-segment contact or crowded dentition. Physiologic spacing was observed more in boys than in girls. In the maxilla, primate space was more frequent than developmental space; however, in the mandible, the difference was low. In the maxilla, the space between the central incisor and the lateral incisor was more frequent than the space between both central incisors. In contrast, in the mandible, the space between both central incisors was more common than the space between the central and lateral incisors or between the lateral incisors and canine. The present study describes the tendency for anterior spacing and crowding in the primary dentition. Further longitudinal studies with a larger sample are needed. Dentists should consider these concepts of spacing or contact/crowding when performing full coronal restorations of primary anterior teeth.

• Journal of the korean academy of Pediatric Dentistry
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• v.5 no.1
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• pp.19-26
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• 1978

The author studied occlusion in the primary dentition of 3~5 year old children and the materials for the present study comprised plaster model of 266 children in Seoul. The results were as followings; 1) In sagittal canine relationship, 63.9%(170 children) showed class 1 pattern, 2.3%(6 children) showed class 2 pattern, 21%(56 children) showed class 3 pattern and 12.8%(34 children) showed a different canine relationship in each side. 2) In sagittal molar relationship, 44.3% 118 children) showed class 1 pattern, 6.1%(16 children) showed class 2 pattern, 32.3%(86 children) showed class 3 pattern and 17.3%(46 children) showed a different molar relationship in each side. 3) In overjet, 87.8%(234 children) showed under 2mm. 4) 5.3%(14 children) showed crossbite and 4.6%(12 children) showed scissors-bite. 5) 21.8%(58 children) showed midline deviation. 6) Primate space was coincided with more common position of interdental space.

• Journal of information and communication convergence engineering
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• v.2 no.2
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• pp.132-137
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• 2004

Most of the current computer vision theories are based on hypotheses that are difficult to apply to the real world, and they simply imitate a coarse form of the human visual system. As a result, they have not been showing satisfying results. In the human visual system, there is a mechanism that processes information due to memory degradation with time and limited storage space. Starting from research on the human visual system, this study analyzes a mechanism that processes input information when information is transferred from the retina to ganglion cells. In this study, a model for the characteristics of ganglion cells in the retina is proposed after considering the structure of the retina and the efficiency of storage space. The MNIST database of handwritten letters is used as data for this research, and ART2 and SOM as recognizers. The results of this study show that the proposed recognition model is not much different from the general recognition model in terms of recognition rate, but the efficiency of storage space can be improved by constructing a mechanism that processes input information.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.3
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• pp.387-393
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• 2009

The purpose of this study was to assess the relationship between interdental spaces and proximal caries in maxillary anterior primary teeth. 555 children aged 3-7 inhabit in Iksan were divided into two groups, depending on the presence of interdental space which was detected by a dental explorer. They were determined to have proximal caries if cavity was formed or the enamel surface was softened. The results were as follows : 1. Regarding interdental spaces, 77.4% had primate spaces; 54.4% had developmental spaces between central and lateral incisor, and 39.0% between central incisors. 2. Interproximal caries incidences in right primary canine, lateral incisor, and central incisor were 6.3%, 14.7%, and 33.5%, respectively. Also interproximal caries incidences in left primary central incisor, lateral incisor, and canine were 33.7%, 16.0%, and 4.7%, respectively. 3. Children with more interdental spaces had less caries incidence, but the relationship was weak(r=-0.024). 4. The mean caries incidence was higher in absence of interdental space of maxillary primary incisors than in presence of space. The mean caries incidence with no interdental space was twice as high as that with presence of interdental space.