• 대한소아치과학회지
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• 제21권2호
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• pp.547-554
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• 1994

Posterior crossbites are abnormal buccal, or lingual relationship of a tooth or teeth of the maxilla, the mandible, or both when the teeth of the two arches are in occlusion and involve the molars and premolars. Posterior crossbites are classified as dental, muscular(functional), or skeletal. In an effort to avoid occlusal interferences caused by the inadequate arch width, the patient deviates the mandible laterally upon closure to achieve maximum intercuspation. This is described as functional posterior crossbite. Correction of functional posterior crossbites in the primary & early mixed dentition as early as possible after diagnosis has been recommended, because crossbites do not automatically improve with the eruption of the permanent teeth. Functional posterior crossbites, if left untreated, may have deleterious effects on the development and function of the TMJ. The diagnosis and management of three cases is presented. Each patient with functional posterior crossbites is treated using the bilateral maxillary expansion appliance.

• 대한소아치과학회지
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• 제24권3호
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• pp.704-709
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• 1997

Space maintainers needs following extraction of primary molars, due to severe dental caries under general anesthesia. Delivery of conventional space maintainers has three of the disadvantages of the method, there being a impression taking and time consuming due to laboratory procedure, and delivery problem due to relaxed tongue. For this problem improved, modified space maintainer is prefabricated before procedure, and adjust, delivery in operation room, favorable results were obtained. The following results were obtained. 1. Delivery time is very reduced than conventional space maintainers. 2. After space maintainer delivery, follow check-up, without impingement of soft tissue, distortion of wire. After space maintainer delivery, continuous research is required so that space maintainer delivery is applied to usual dental treatment, and it is necessary of long term research.

• 대한소아치과학회지
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• 제32권4호
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• pp.628-633
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• 2005

유구치의 깊은 우식은 치수병소을 유발하고 이를 조기에 치료하지 않을 경우에는 치수강저의 수많은 부근관을 통하여 치근분지부 병소로 이어진다. 지금까지 대부분의 교과서나 문헌에서는 이와 같은 경우를 발치의 적응증으로 기술하여 왔고 임상에서도 상례적으로 발치를 흔히 시행하였다. 그러나 유구치의 조기 상실은 수많은 부작용을 낳는 것이 필연적이다. 어린이의 골재생 능력 이 우수하며, 치수강저와 치근분지부를 잇는 많은 부근관이 있음을 생각해 볼 때 유구치 치수 내의 감염원을 치수절제술로 제거하고, 이미 발생한 치근분지부 병소에 대해서는 소파술을 시행한다면 치근분지부 골조직의 신속한 재생이 가능하지 않을까 하는 의문이 제기되었다. 본 증례는 $3{\sim}6$세 어린이에서 유구치 치근분지부 방사선 투과상이 $2{\sim}4mm$ 정도의 깊이를 보이는 비교적 경미한 수준이면서, 연조직 누공을 보이는 10개 증례를 선별하여 치수절제술과 치근분지부 소파술을 시행한 결과, 모두에서 방사선적으로 골재생이 관찰되었다. 이를 통하여 유구치 치근분지부 병소나 누공을 보이는 모든 경우가 발치의 적응증은 아니며, 이 방법이 치근분지부 병소를 가진 유구치를 잔존시킬 수 있는 하나의 대안이 될 수 있음을 알 수 있었다. 그러나 이 방법이 객관적 인 타당성을 얻기 위해서는, 병소의 크기와 진행정도, 계승 영구치의 성숙도, 환아의 연령 등 적응증에 대한 보다 심층적인 검토와 연구가 필요할 것으로 사료되었다.

• Restorative Dentistry and Endodontics
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• 제3권1호
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• pp.12-16
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• 1977

One hundred human maxillary first molars were injected with china ink, decalcified, cleared, and used in vitro study to determine the number of root canals, the frequency and location of lateral canals, canals per root, and frequency of apical deltas. The results were as follows; 1. The mesiobuccal root was found to contain a single primary canal in 53% of the teeth studied and two canals in 47 % of the teeth studied. 2. In mesiobuccal roots with two canals, the seperated apical foramen appeared 32% of the specimens and the common apical foramen 15% of the specimens. 3. Of the 347 canals studied, 26.9% of the canals were found to contain lateral canals and these ramifications were mainly located in the apical third of the root.

• Restorative Dentistry and Endodontics
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• 제6권1호
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• pp.83-86
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• 1980

Fifty human maxillary second molars were injected with china ink, decalcified, cleared, and used in vitro study to determine the number of root canals, the frequency and location of lateral canals, canals per root, and frequency of apical deltas. The results were as follows. 1. The mesiobuccal root was found to contain a single primary canal in 62% of the teeth studied and two canals in 38% of the teeth studied. 2. In mesiobuccal roots with two canals, the seperated apical foramen appeared 24% of the specimens and the common apical foramen 14% of the specimens. 3. Of the 169 canals studied, 23.1% of the canals were found to contain lateral canals and these ramifications were mainly located in the apical third of the root.

• 대한소아치과학회지
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• 제47권4호
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• pp.438-445
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• 2020

우상치는 수직적으로 긴 치수강과 근첨부에 위치하는 치수저를 특징으로 가지는 발육성 형태 이상이다. 이 연구의 목적은 어린이의 유구치에서 우상치의 유병률과 특징을 알아보기 위한 것이다. 이 연구는 2005년부터 2018년까지 연세대학교 치과대학병원 소아치과에 내원하여 파노라마 방사선 사진을 촬영한 만 5세에서 10세 사이의 환자 2,473명을 대상으로 시행되었으며 총 19,784개의 유구치가 평가되었다. 우상치의 유병률은 약 5.7%었고 남아에서 더 호발하였다. 또한 상악에서 6.3%, 하악에서 93.6%로 하악에서 현저히 높은 유병률을 보였다. 좌우에 따른 유병률의 차이는 나타나지 않았다. 우상치의 세부 유형으로 Daito의 방법을 적용하여 Hypertaurodontism, Mesotaurodontism, Hypotaurodontism으로 분류하였으며 각 유병률은 11.9%, 78.2%, 7.8%로 Mesotaurodontism이 가장 높은 유병률을 보였다.

• 대한소아치과학회지
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• 제42권3호
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• pp.257-263
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• 2015

매복치는 유치열기보다 영구치열기에서 더 높은 빈도로 발생한다. 가장 흔하게 이환되는 치아는 상하악 제3대구치들이며, 하악 제1대구치의 매복은 비교적 드문 편이다. 매복치의 치료방법은 자발적 맹출을 위한 지속적인 검사, 외과적 노출술, 외과적 노출 후 아탈구, 교정적 견인, 그리고 외과적 재위치술 등이 있으며 이 모든 치료가 실패한다면 치아를 발거하는 것을 고려할 수 있다. 첫 번째 증례는 8세 남아로서 매복된 하악 제1대구치에 폐쇄장치를 이용한 감압술을 시행하였으며, 정기적인 검진을 통해 치아의 맹출이 관찰되었다. 두 번째 증례는 12세 남아로서 매복된 하악 제1대구치의 외과적 노출술을 시행 후 치아의 맹출이 관찰되지 않아 가철성 장치를 이용한 교정적 정출술을 시행하였으며 이 후 정상적인 치아의 맹출이 관찰되었다.

• 대한소아치과학회지
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• 제23권2호
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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.

• 대한치과교정학회지
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• 제15권2호
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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.

• Journal of Oral Medicine and Pain
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• 제19권1호
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• pp.57-72
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• 1994

This study was undertaken to obtain the data age determination following the eruption of individual cusps of the first molars in the point of forensic odontology. 532 children (294 male and 238 female, born between April, 1989 and March, 1986) from a kindergarten and a primary school in a reesidential district in Seoul were studied. The eruption state of the first molar was divides into 6 stages according to the degree of exposure of individual cusps, and correlation between the stage and age was stastically analysed. The results of the study lead to following conclusions : 1. The most frequently seen eruption sequence of cusps for the upper first molar was mesibuccal cusp, mesiopalatal cusp, distobuccal cusp, mesiodistal cusp, distopalatal cusp. As for the lower first molar : mesiobuccal cusp, mcsiolingual cusp, distobuccal cusp, distolingual cusp. 2. The time of eruption was earlier in the female ethan in the male, but it was stastically remarkable only in upper and lower parts of the right and the left teeth of subjects age between 6.0 and 6.5 and upper part of the right and the left teeth of subjects age over 7.5 3. The eruption of the lower first molar was comparatively earlier than that of the upper first molar and there was no significant stastical difference between the right and the left first molars in the time of eruption. 4. There was no noticeable difference in the eruption sequence of cusps, irrespective of sex and side. 5. The eruption of the upper first molar is started at the age of about 6.4 and complete the age of about 7.1 and as for the lower first molar, it is from 6.3 to 7.0