• Restorative Dentistry and Endodontics
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• 제10권1호
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• pp.169-175
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• 1984

This study was undertaken to obtain the average canal length of upper & lower anterior teeth which was important in canal length measuring procedure of endodontic treatment. It was based upon 827 out-patients who had endodontic treatment on their upper & lower anterior teeth at the Department of Operative Dentistry, Dental Infirmary, Yonsei Medical Center from February, 1978 to June, 1984. The 1249 teeth of these patients were devided into sex and age groups. The root canal length of these teeth were measured. The following results were obtained; 1. The mean root canal length of upper & lower anterior teeth were as follows; Upper central incisors : 21.8mm Upper lateral incisors : 21.0mm Upper canines : 24.1mm Lower central incisors : 18.6mm Lower lateral incisors : 19.9mm Lower canines : 22.6mm 2. There was no significant difference in root canal length between sex. (P > 0.05) 3. There was no significant difference in root canal length between age groups. (p > 0.05) 4. The distribution of upper central incisors showed the highest distribution followed by upper lateral incisors and lower central incisors between 10 to 40 year old age groups, and there was no signigicant difference in the rest of the age groups. There was no significant difference in sex distribution, which was 49.5% for males and 50.4% for females. The number of the upper anterior teeth was 74.3% of all the specimens and the lower anterior 25.7%, and 40.6% of all the specimens were upper central incisors.

• 대한소아치과학회지
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• 제25권1호
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• pp.152-156
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• 1998

The purpose of this study was to investigate the prevalence rate of the nursing caries in preschool children by retrospective epidemiological survey. 500 preschool children in Iksan city were examined for their dental caries experience (dt, mt, ft). Subjects were divided stepwise by the pattern of caries experience: Group 1-no caries, Group 2-no caries in the upper arch, Group 3-no caries among the upper incisors, Group 4-dmft in the lower arch $\geq$ mft in the upper arch, Group 5-dmft among the upper molars > dmft among the upper incisors, Group 6-dmft among the upper molars < dmft among the upper incisors+caries among the lower incisors, and Group 7-the rest. Groups 6 was regarded as the group which had experienced rampant caries, and the Group 7 was regarded as the group which had the typical pattern of nursing caries. The prevalence rate of nursing caries (Group 7) was 16.0%.

• 대한치과의사협회지
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• 제12권6호
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• pp.377-379
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• 1974

A rare case of two supernumerary teeth on the lingual side of the upper central incisors was observed in a 17 year old korean male. The characteristics were as follow : 1) The site of the occurrence was on the lingual side of upper central incisors. 2) The sizes of both supernumerary teeth were smaller than the normal incisor teeth and quite different from the normal incisors in the tooth shape. 3) A diastema was seen between the maxillary central incisors, and the right incisor exhibited labioversion and left incisor exhibited some mesial inclination.

• 대한소아치과학회지
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• 제26권1호
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• pp.1-13
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• 1999

To study the caries patterns in primary dentition, 719 preschool children, 4-6 years old, were examined for their caries activity(salivary reductase activity) and caries experience of individual teeth. Teeth groups were made by cluster analysis using dft indexes of individual teeth as criteria. The six major teeth groups in the order of dft index from high to low were (1) lower primary molars, (2) upper primary molars, (3) upper central incisor, (4) upper lateral incisor, (5) canines, and (6) lower incisors. There were significant differences in dft index between teeth groups except upper lateral incisor and canines. Upper and lower primary molars showed the highest correlation in dft index, and the next couples were upper central incisors and upper lateral incisors, upper lateral incisor and canines, upper central incisor and canines, upper lateral incisor and upper primary molars, and canines and upper primary molars in descending order. Upper first primary molar showed the greatest differences in dft index between caries activity levels.

• Journal of Oral Medicine and Pain
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• 제6권1호
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• pp.101-110
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• 1981

For the purpose of an estimation of age based on the changes in the human dental cavity caused by increase in age, 1,208 extracted teeth in the parts from central incisors and lateral incisors and lateral incisors to second premolars of upper and lower, right and left side were evaluated and analized all of surface index of pulp cavity. The results are as follows : 1. The surface index of pulp caxities of upper and lower, central and lateral incisors, and tend to decrease regularly as the age increase. So above teeth are more applicable to age estimation than canine and premolars. 2 For the purpose of age estimation by surface index of pulp cavity of central and lateral incisor, linear equations are as follows. Upper central incisor: X=(16.301-Y)/0.12 Upper lateral incisor: X=(16.620-Y)/0.11 Lower central incisor: X=(20.963-Y)/0.16 X=Age Y=Surface index of pulp cavity Correlation coefficient between chronologic age and estimated age is 0.699 3.The least error(3.3 yrs of age)reveals in 41-45 age group, which shows the highest possibility of estimation of age. The highest error(4.1 yrs of age)reveals in 61-65 age group and 56-60 age group.

• 대한치과교정학회지
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• 제21권3호
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• pp.685-699
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• 1991

The purpose of this report is to review vertical dysplasia such as openbite or deep bite in skeletal Class III malocclusion and their treatment modality and to present two cases treated with MEAW. The results obtained were as follows A. Open bite case 1. The treatment time was 3 year 8 months. 2. Upper and lower incisors showed extrusion and especially lower anterior alveolar process showed remodelling. 3. The mesially inclined upper and lower molars were uprighted and especially lower first molars showed extrusion that means remodelling of alveolar bone. 4. Normal overbite and overjet were established. 5. Mandible showed slight clockwise rotation. 6. Maxilla showed slight downward bending of ANS part. 7. Upper lip showed downward drop and lower lip showed retraction and touch between upper and lower lip was established. 8. Tongue posture of post-treatment was more raised than pretreatment. B. Deep bite case 1. The treatment time was 1 year 8 months. 2. Upper incisors showed intrusion and labioversion and lower incisors showed slight intrusion and linguoversion. 3. The lower molars showed distal uprighting and intrusion and upper molars showed mesial movement and extrusion. 4. Normal overbite and overjet were established. 5. Maxilla did not show downward movement. 6. Mandible showed slight clockwise rotation. 7. Lower lip showed retraction and downward drop and upper lip showed downward drop.

• 대한치과교정학회지
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• 제17권1호
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• pp.93-106
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• 1987

The purpose of this study was to investigate the fittness of Golden relation items was advocated by Ricketts whether or not it is applicable to the young adult Korean dentitions and also to evaluate the several new Golden relation items conducted by the author. The material was consisted of 81 dental casts (34 male, 47 female) with ideal occlusion, which never undergone orthodontic, prosthodontic procedures. Measurements were made on the arch dimensions using sliding caliper (Mitutoyo. Co) and data were computerized and analyzed. The findings of this study were as follows, 1. The Golden proportion advocated by Ricketts dose not seem to directly applicable to the Korean normal dentition, however, the modification from the Ricketts' original shows the Golden proportion as follow: A first series of progressive Golden relations was found on the Golden ratio among the lower central incisors width, the inter mesioincisal width of the upper lateral incisors, and the upper first premolars width. A second series was found on the Golden ratio among the lower lateral incisors width, lower inter canine tips width and theupper first molar distal cusp tips width. A third series was found on the Golden ratio between the inter distal aspect width of e lower canine and the mesial cusp tips width of the lower second molars or inter cusp tips width of upper second premolars. 2. In addition to Ricketts' original, 4 new Golden proportions were found in young adult Korean dentition, these are as follows; The tips of lower canine width had Golden relation with the width of the upper first premolar buccal cusp tips or the width of the lower first molar central fossae. The distal aspect of the lower first premolars had Golden relation with the buccal surface widths of the lower or upper second molars. The width of upper lateral incisors had Golden relation with the upper second molar height. The width of the lower canine tips had Golden relation with the lower second molar height.

• 대한치과교정학회지
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• 제22권3호
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• pp.735-753
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• 1992

악골형태에 따른 상하악절치의 위치를 분석하기 위하여 18세 이상되는 정상교합자 60명과 II급 1류 부정교합자 40명, 그러고 III급 부정교합자 40명의 측모 두부방사선규격 사진을 설정한 계측점과 계측항목에 따라 분석하여 다음과 같은 결과를 얻었다. 저작계와 관련된 계측항목인 CI angle은 정상교합자군에서 $89.20{\pm}4.34^{\circ}$, II급 1류 부정교합자군에서 $81.68{\pm}5.95^{\circ}$, III급 부정교합자군에 $101.96{\pm}6.31^{\circ}$이었다. 상하악절치위치 계측항목의 악골형태별 비교에서 정상교합자군에 대한 II급 1류 부정교합군은 상악절치가 모든 계측항목에서 유의한 차를 보이며 순측경사져 있고(p<0.05), 하악절치도 ${\angle}LI-APog$, LI-APog(m), ${\angle}LI-AB$, LI-AB(mm)를 제외한 모든 계측항목에서 유의한 차이를 보이며 순측경사져 있었다(p<0.05). III급 부정교합자군은 상악절치가 ${\angle}UI-SN,\;{\angel}UI-OP$을 제외한 모든 계측항목에서 유의한 차를 보이며 순측경사져 있고 하악절치는 모든 항목에서 유의한 차이를 보이며 설측 경사져 있었다(p<0.05). 모든 악골형태에서 ${\angle}LI-SN,\;{\angel}LI-FH$가 악골계측항목과 비교적 상관성이 있었고, FMA가 하악절치위치계측항목과 비교적 상관성이 있었다. 악골형태에 상관없이 일정하게 적용할 수 있는 기준선은 상악절치 계측항목에서는 AB선, 하악절치 계측항목에서는 APog선이었다.

• 대한치과교정학회지
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• 제21권2호
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• pp.273-285
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• 1991

Crowded group is composed of 60 subjects who visited Yonsei University for orthodontic treatment and has no history of orthodontic treatment. Noncrowded group is composed of 26 subjects who has no crowding, considered to have a normal occlusion and no history of orthodontic treatment. Currently available and approved analytic method was used. Interrelationship between tooth size and arch size, and it's correlation on tooth crowding was studied and the following results were obtained. 1. In comparison of sum of mesiodistal width, of crown size of teeth was greater in noncrowded group than that of crowded group on both arch. (p < 0.01). 2. In comparison of arch lengths, the values measured from arch length 2 showed greater in noncrowded group (p < 0.01). Also in crowded group, arch length 1 showed greater value than arch length 2 on both arch (p < 0.01). 3. In comparison of arch widths, upper interlateral (p < 0.01) and upper intercanine width (p < 0.05) showed greater value in noncrowded group on upper arch and intermolar width showed greater value in noncrowded group on both upper and lower arches (p < 0.05). 4. In comparison of arch perimeters, arch perimeter 2 was greater value in noncrowded group on both upper and lower arches (p < 0.01). 5. Dentoalveolar disproportion was greater in noncrowded group on both upper and lower arches (p < 0.01). 6. In lower incisors MD/FL ratio, the central and lateral incisors were greater in crowded group, but statistial significance was only in lateral incisors (p < 0.01) 7. The irregularity index of lower incisors showed greater value in crowded group (p < 0.01).

• 대한소아치과학회지
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• 제28권4호
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• pp.547-552
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• 2001

교정치료를 목적으로 한 하악 전치의 발거는 교합에 부정적인 영향을 끼치는 것으로 여겨져 왔으나 적절히 사용한 경우에 부정교합 치료의 한 방향으로써 선택적으로 사용될 수 있다. 대개 총생에 대한 치료는 비발치와 4개의 소구치 발거 사이에 선택하는 경향이 있다. 총생이 있는 하악 전치의 치료를 위한 다양한 접근 방법은 구치의 원심이동, 견치의 외측이동, 전치의 순측이동, 인접면 법랑질 삭제, 소구치 발거, 한 개 또는 두 개의 전치 발거 및 이상의 복합적인 방법들이 있다. 전치의 발거는 총생이 있거나 전치부 치아크기의 불일치 및 상악 전치의 선천적인 소실이나 이소성 맹출 등에 의해 발거한 경우에 조화를 위해서이다. 하지만 수직피개가 크고 공간이 있는 경우는 피해야 하며 전치부 수직피개의 증가는 흔한 부작용이다. 본 증례에서는 상악 전치부에 심한 총생이 있고 상악 좌측 측절치의 매복과 우측 측절치의 구개측 이소성 맹출로 인해 발거한 경우로써 하악 전치부에도 심한 총생이 있었다. 따라서 요구되는 공간, 안모의 심미성, 전방교합관계, 견치간 폭경, 적은 치아이동, I급 교합관계, 발치시기 및 수직 수평피개 등을 고려하여 하악 양측절치를 발거하였다. 이에 본 증례는 상악 측절치의 매복 및 이소성 맹출을 동반한 상하악 전치부의 심한 총생이 있는 초기 영구치열기의 남아에서 상하악 양측절치를 발거하고 고정식 장치를 사용하여 공간 폐쇄 및 견치 shaping을 통한 교정치료를 하여 양호한 결과를 얻었기에 보고하는 바이다.