• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권2호
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• pp.103-115
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• 2009

In vertebrates, the face is mainly formed with neural crest derived neural crest cells by the inherent programs and the interactive environmental factors. Extracellular signaling-regulated kinase (Erk) is one of such programs to regulate the various cellular functions. And retinoic acid (RA) also plays an important role as a regulator in differentiation process at various stages of vertebrate embryogenesis. We wanted to know that the segregation as well as the patterning of maxillary and mandibular structure is greatly influenced by the maxillomandibular cleft (MMC) and the failure of this development may result in the maxillomandibular fusion (syngnathia) or other patterning related disorder. It has been well documented that the epithelium at this cleft region has significant expression of Fibroblast growth factor (Fgf) 8, and it is essential for the patterning of the first arch derived structures. By the morphological, skeletal, cell proliferation and apoptotic, and hybridization analysis, we checked the effects of Erk inhibition and/or RA activation onto MMC and could observe that Erk and RA signaling is individually and synergically involved in the facial patterning in terms of FGF signaling pathway via Barx-l. So RA and Erk signaling work together for the MMC patterning and the segregation of maxilla-mandible by controlling the Fgf-related signaling pathways. And the abnormality in MMC brought by aberrant Fgf signaling may result in the disturbances of maxillary-mandibular segregation.

• 대한소아치과학회지
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• 제29권1호
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• pp.44-50
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• 2002

Apert syndrome은 첨두합지증(acrocephalosyndactly)중의 하나로, 1906년 Apert에 의해 보고된 증후군이며 관상봉합의 조기유합에 의한 첨두증(acrocephaly)과 합지증이 공존하는 선천성 유전 질환이다. 임상적으로 뾰족한 고깔모양의 머리 형태를 하고 있으며, 손과 발이 합지증을 보이는 것이 가장 특징적이다. 상염색체 우성의 유전을 하며 중안면부의 발육부전으로 인한 안구돌출 경도의 양안이개 및 상악골 발육부전을 나타내고, 고구개, 연구개열을 동반하는 경우가 있으며, 하악 발육은 정상이나 상대적으로 하악 전돌의 양상을 나타내고 좁은 상악과 하악궁에 심한 총생이 나타나고, 골격적 이상에 의한 부정 교합과, 전방부의 개교를 유발한다. 본 증례는 성형외과에서 상악과 하악에 대한 교정적 처치의 가능성에 대하여 의뢰된 3세 1개월의 Apert syndrome 남아에 대한 것으로 의학적 기왕력과 향후 치과적 처치방향에 대해 과거의 문헌을 고찰하고, 교정적 진단과 치료계획의 수립과정 중에 다소의 지견을 얻었기에 이에 대해 보고하는 바이다.

• 대한소아치과학회지
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• 제25권1호
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• pp.134-143
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• 1998

Twin Blocks are simple bite-blocks that effectively modify the occlusal inclined plane to induce favorably directed occlusal forces by causing a functional mandibular displacement. These devices use upper and lower bite-blocks that engage on occlusal inclined planes. Twin Blocks use the forces of occlusion as the functional mechanism to correct the malocclusion. To get an excellent result in the treatment by using the Twin Block appliances, proper case selection must be needed. Twin Block treatment is performed in two stages. Twin Blocks are used in the active phase to correct the anteroposterior relationship and establish the correct vertical dimension. Once this phase is accomplished, the Twin Blocks are replaced with an upper Hawley type of appliance with an anterior inclined plane, which is then used to support the corrected position as the posterior teeth settle fully into occlusion. The Twin Block is the most comfortable, the most esthetic ane the most efficient of all the functional appliances. Twin Blocks have many advantages compared to other functional appliances. Patients can wear Twin Blocks 24 hours per day and can eat comfortably with the appliances in place. From the moment Twin Blocks are fitted, the appearance is noticeably improved. There is less interference with normal function. Integration with conventional fixed appliances is simpler than with any other functional appliance. Twin Blocks allow independent control of upper and lower arch width. Appliance design is easily modified for transverse and sigittal arch development. The authors treated Class II malocclusion with Twin Blocks. and the results as follows; 1. Rapid profile improvement was achieved in 2-3 months. 2. There was excellent patient cooperation. 3. Severe overjet and overbite were reduced. 4. Class II molar relationship was changed to Class I.

• 대한치과교정학회지
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• 제2권1호
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• pp.47-52
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• 1971

저자들은 9세 10개월된 Class I discrepancy 증례를 다각적으로 검사한 후 그의 가족력과 Grater. Nance, Mills, Lloyd, Dewe, 등의 생각대로 Clinical arch lenth의 증가를 더 기대할수 없다고 판단하고 연속발치를 시술하여 전치부의 교우교합과 총생이 거의 해소되어 좋은결과를 보이고 있으나, 두부X-선 규격 사진분석에서 보는바와 같이 Interincisal angle이 약간 크므로 향후 예견되는 Deep Overbite와 Incisal Inclination Control에 치료의 역점를 두고자한다.

• BMB Reports
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• 제45권6호
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• pp.337-341
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• 2012

Different from humans, who have a continuous dentition of teeth, mice have only three molars and one incisor separated by a toothless region called the diastema in the hemi mandibular arch. Although tooth buds form in the embryonic diastema, they regress and do not develop into teeth. In this study, we evaluated the proteins that modulate the diastema formation through comparative analysis with molar-forming tissue by liquid chromatography-tandem mass spectroscopy (LC-MS/MS) proteome analysis. From the comparative and semi-quantitative proteome analysis, we identified 147 up- and 173 down-regulated proteins in the diastema compared to the molar forming proteins. Based on this proteome analysis, we selected and evaluated two candidate proteins, EMERIN and RAB7A, as diastema tissue specific markers. This study provides the first list of proteins that were detected in the mouse embryonic diastema region, which will be useful to understand the mechanisms of tooth development.

• 대한소아치과학회지
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• 제21권2호
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• pp.555-560
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• 1994

Among the permanent teeth. the first permanent molars play the greatest role in occlusion and function. So, the congenital missing, abnormal reuption or abnormal formation of the first permanent molars in the course of arch development would inflict normal development of dental arches. Therefore, early detection of abnormal cases related to first permanent molars and understanding of current and predictable clinical problems are essential for proper occlusal guidance in children. With the aim of investigating the clinical patterns of delayed eruption of first permanent molars in children, panoramic tomograms of the childern in mixed and early permanent dentition were observed and analyzed. The results were as follows: 1. Among the delayed eruption of first permanent molars, on tooth or bilateral teeths were affected most frequently. Delayed eruption was more prevalent in maxilla than in mandible. 2. The formation of tardily erupted teeth were also delayed. 3. Delayed eruption was generally limited in first molars or molar segments. 4. Delayed eruption of first permanent molars is accompanied by abnormal position of tooth germs, for example, ectopic eruption, delayed dental age, delayed localized tooth formation and generalized congenital missing. 5. There was a tendency of delayed formation or congenital missing of second molars distal to tardily erupted 1st molars. And that was more marked in maxilla than in mandible. 6. There was reported that affected 1st molars show various size and shapes. Maxillary 1st molars showing delayed eruption showed a tendency of having 3 cusps. But, tardily erupted mandibular 1st molars showed no significant reduction in mesiodistal dimension, as reported. 7. In some cases, the delayed eruption of 1st permanent molars was associated with ectopic eruption, but their formation was not usually retarded. 8. In skeletal class III cases, there showed a tendency of mandibular 1st molars to erupt earlier than maxillary 1st molars with greater interval than in normal occlusion.

• 대한소아치과학회지
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• 제28권1호
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• pp.175-179
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• 2001

국소적 치아 이형성증이란 드물게 나타나는 치아발육장애로서 치아발육이 국소적으로 정지되어 발생되며 이환된 치아의 모든 구성요소가 발육부전이나 석회화 부전을 나타낸다. 국소적 혈액 순환 장애, 체성 돌연변이. 바이러스 침투, 치배 감염, 치아 외상, 이상고열, 방사선조사, 영양, 대사 장애, 유전 등이 원인으로 제시되고 있으나 정확한 원인은 밝혀져 있지 않다. 여성에 많이 발생하고(1.4 : 1) 하악보다는 상악(특히 좌측)에 많이 나타나는 것으로 보고되고 있다. 이환 받은 치아는 크기가 작고, 저형성을 보이며, 노란색 또는 노란 갈색을 띄고, 소와와 구(pitting & grooving)를 보이기도 한다. 방사선적으로 "ghost like appearance" "fuzzy appearance"등을 보이고 치수강 내에 치수석회화물이나 상아질석이 보이기도 한다. 본 증례의 2세 남자 환아는 하악 우측 치아의 맹출 지연을 주소로 연세대학교 병원 소아치과에 내원하였다. 하악 우측 유중 절치의 부분 맹출과 유측절치, 유견치, 제 1유구치가 미맹출을 보였고, 방사선 검사소견에서 해당부위의 치아는 "Ghost like appearance"와 짧은 치근, 개방된 치근첨의 소견이 관찰되었다. 임상, 방사선 검사결과 국소적 치아 이형성증으로 판단되어 이에 대한 보고를 하는 바이다.

• 대한치과교정학회지
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• 제47권6호
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• pp.365-374
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• 2017

Objective: The objective of this study is to investigate the eruption pattern and root resorption of the bovine anterior dentition in relation to growth-related parameters based on dental maturity. Methods: A cross-sectional study was conducted on 110 bovine anterior mandibles by using standard radiography, cone-beam computed tomography (CBCT), and actual measurements. We determined the relationships between the stages of dental maturity by using a modification of Demirjian's method and various growth-related parameters, such as the activity of the root-resorbing tissue and mobility of the deciduous teeth. The correlation of growth-related parameters with interdental spacing and distal unusual root resorption (DRR) of the deciduous fourth incisor was assessed. The cause of mesial unusual root resorption (MRR) of the deciduous fourth incisor was determined on the basis of the arrangement of the permanent third incisor. Results: An independent t-test and chi-square test indicated significant differences in growth-related parameters associated with dental arch length discrepancy and factors related to the shedding of deciduous teeth between the low and high dental maturity groups. The samples with interdental spacing and DRR showed a larger sum of mesiodistal permanent crown widths and higher dental maturity than did the respective controls. Samples with MRR tended to show a lingually rotated distal tip of the adjacent tooth crown. Conclusions: Dental maturity has relevance to the interdental spaces and unusual root resorption of mixed dentition. The position of the adjacent tooth crown on CBCT may be correlated with the occurrence of unusual root resorption of the incisor.

• 대한소아치과학회지
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• 제31권1호
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• pp.41-45
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• 2004

정상적인 하악 성장에서, 하악 제1대구치 후방의 치배는 근심경사되어 있다. 보통 이러한 근심경사는 자발적으로 해소되나, 항상 그런 것만은 아니다. 첫 번째 증례는 14세 여아로서 가족이 모두 하악 제2대구치가 매복된 병력을 가지고 있었다. 환아 역시 양측 모두 매복되어 분절호전과 개방용 코일 스프링으로 치료하였다. 두 번째 증례는 14세 남아 환자로 Halterman 장치를 이용하여 매복된 하악 우측 제2대구치를 치료하였다. 세 번째 증례는 11세 남아로서 고정성 교정 치료 중 하악 양측 제2대구치가 매복되었다. 분절호선과 개방용 코일 스프링, 구리선으로 치료하였다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제21권4호
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• pp.407-413
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• 1999

구강악안면부위의 선천성 기형은 복잡한 발생학적 과정과 연관이 있으며 비정상적인 기형을 적절한 시기에 치료하지 못할 경우 이로 인한 이차적인 기형을 유발하여 치료를 더욱 어렵게 할 수 있다. 저자 등은 우측 상악돌기 후외하방에 중복 발생된 상악돌기와 과잉치로 인하여 저작장애를 보이며, 안와, 관골 및 상하악골의 심한 안모 비대칭 소견을 보이는 악안면기형환자를 골절제와 발치, 교정치료, 관골과 안와재건술, 악교정수술 및 반흔교정술 등의 4회에 걸친 수술을 통해 심미적, 기능적으로 만족스러운 결과를 얻었다. 악안면영역의 선천성 기형의 치료는 매우 난이하며 수차례의 수술을 요하고 수술 결과가 만족스럽지 못한 경우가 많으므로 사전 철저한 분석이 요구되며, 환자의 심리적 부담을 덜어주기 위한 특별한 배려가 요구된다.