• 대한치과교정학회지
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• 제25권5호
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• pp.587-592
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• 1995

교정력에 의한 치아이동시 발생하는 골침착과 흡수의 골재형성 과정을 교정력의 크기와 적용기간에 따라 비교해 보고자 하였다. 성견 6마리를 대조군 1마리와 실험군 5마리로 나누어 실험군에서는 하악 제 1,2소구치 사이에 open coil spring을 장착해서 좌측에는 강한 힘(250-300g), 우측에는 약한 힘(50-75g)이 가해지도록 하여 12시간, 24시간, 3일, 1주, 2주에 각각 희생시켰다. 분리된 조직편에 대해 연X선 촬영을 하여 분석한 결과 다음과 같은 결과를 얻었다. 1. 견인측에서의 신생골 형성은 7일째부터 관찰되기 시작하여 14일째에는 광범위한 부위에서 방사선 불투과상을 관찰할 수 있었으나 힘의 크기에 따른 비교는 불가능하였다. 2. 압박측에서의 치조골 흡수는 3일째에 치조백선의 파괴로 나타나기 시작하여 7일째, 14일째에 걸쳐 증가되는 양상을 보였다.

• 대한치과의사협회지
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• 제15권8호
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• pp.623-626
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• 1977

The author made two implant blades of gold alloy metal, and applied CEKA attachment to one blade. These two blades were implanted at the sockets resulting from removal of both 3rd premolar of experimental dog. Simple crown and tooth supporting denture was constructed on the implanted blades the author observed above mentioned procedures for 8 weeks. The obtained results were as follows; 1) There is no remarkable necrosis of supporting alveolar bone on both sides So, metal reaction was favourable. 2) Masticatory force which is loaded on each tooth was not effective on the alveolar bone.

• Journal of Periodontal and Implant Science
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• 제45권6호
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• pp.216-222
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• 2015

Purpose: After extraction, the alveolar bone tends to undergo atrophy in three-dimensions. The amount of alveolar bone loss in the horizontal dimension has been reported to be greater than the amount of bone loss in the vertical dimension, and is most pronounced in the buccal aspect. The aim of this study was to monitor the predictive alveolar bone level following the extraction of anterior teeth seriously involved with advanced chronic periodontitis. Methods: This study included 25 patients with advanced chronic periodontitis, whose maxillary anterior teeth had been extracted due to extensive attachment loss more than one year before the study. Periapical radiographs were analyzed to assess the vertical level of alveolar bone surrounding the edentulous area. An imaginary line connecting the mesial and the distal ends of the alveolar crest facing the adjacent tooth was arbitrarily created. Several representative coordinates were established in the horizontal direction, and the vertical distance from the imaginary line to the alveolar crest was measured at each coordinate for each patient using image analysis software. Regression functions predicting the vertical level of the alveolar bone in the maxillary anterior edentulous area were identified for each patient. Results: The regression functions demonstrated a tendency to converge to parabolic shapes. The predicted maximum distance between the imaginary line and the alveolar bone calculated using the regression function was $1.43{\pm}0.65mm$. No significant differences were found between the expected and actual maximum distances. Likewise, the predicted and actual maximum horizontal distances did not show any significant differences. The distance from the alveolar bone crest to the imaginary lines was not influenced by the mesio-distal spans of the edentulous area. Conclusions: After extraction, the vertical level of the alveolar ridge increased to become closer to the reference line connecting the mesial and distal alveolar crests.

• 구강회복응용과학지
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• 제27권2호
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• pp.141-147
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• 2011

본 연구는 상악동골이식술에 사용된 다양한 골이식재와 자가치아골이식재의 효율성을 비교하고 조직형태계측학적으로 평가하는 것이다. 2007년 10월부터 2009년 9월까지 분당서울대학교병원에서 상악동골이식술을 시행 받은 24명의 환자들을 대상으로 하였다. 환자들의 평균 나이는 $52.51{\pm}11.86$세였다. 모든 증례들은 사용된 골이식재의 종류에 따라 3그룹으로 분류되었다. 1군: 자가치아골이식재, 2군: OrthoblastII(integra lifescience corp. Irvine, US)+Biocera(Osscotec, seoul, korea), 3군: DBX(Synthes, USA)+BioOss(Geistlich Pharm AG, Wolhusen, Switzerland). 총 37개의 임프란트가 식립되었다(1군: 7, 2군: 10, 3군: 20). 신생골 형성, 직골과 층판골의 비율, 신생골과 골이식재의 비율을 조직형태계측학적으로 평가하였다. 통계처리는 SPSS Ver. 12.0을 사용하여 Kruskal-Wallis test를 시행하였다. 신생골 형성 비율은 1군 $52.5{\pm}10.7$, 2군 $52.0{\pm}23.4$, 3군 $51.0{\pm}18.3$였고 통계적으로 유의성 있는 차이는 없었다. 직골과 층판골의 비율은 1군 $82.8{\pm}15.3$, 2군 $36.7{\pm}59.3$, 3군 $31.0{\pm}51.2$였다. 신생골과 잔존골이식재의 비율은 1군 $81.3{\pm}10.4$, 2군 $72.5{\pm}28.8$, 3군 $80.3{\pm}24.0$였다. 4개월의 치유기간 후에 모든 군에서 양호한 신생골 형성이 이루어졌다. 본 연구의 제한적인 범위 내에서 자가치아골이식재는 상악동골이식에 사용될 수 있는 새로운 골이식재료라고 사료된다.

• International Journal of Oral Biology
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• 제40권1호
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• pp.1-9
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• 2015

Osteocalcin (OC) is the most abundant noncollagenous protein of extracellular matrix in the bone. In an OC deficient mouse, bone formation rates are increased in cancellous and cortical bones. OC is known as a negative regulator of mineral apposition. OC is also expressed in the tooth of the rat, bovine, and human. However, little is known about OC during tooth development in Xenopus. The purpose of this study is to compare the expression of OC with mineralization in the developing tooth of Xenopus, by using von Kossa staining and in situ hybridization. At stage 56, the developmental stage of tooth germ corresponds to the cap stage, and an acellular zone was apparent between the dental papilla and the enamel organ. From stage 57, calcium deposition was revealed by von Kossa staining prior to OC expression, and the differentiated odontoblasts forming predentin were located at adjoining predentin. At stage 58, OC transcripts were detected in the differentiated odontoblasts. At stage 66, OC mRNA was expressed in the odontoblasts, which was aligned in a single layer at the periphery of the pulp. These findings suggest that OC may play a role in mineralization and odontogenesis of tooth development in Xenopus.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제35권2호
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• pp.73-81
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• 2013

Purpose: Smad4 is a central mediator for transforming growth factor-${\beta}$/bone morphogenetic protein ($TGF-{\beta}/BMP$) signals, which are involved in regulating cranial neural crest cell formation, migration, proliferation, and fate determination. Accumulated evidences indicate that $TGF-{\beta}/BMP$ signaling plays key roles in the early tooth morphogenesis. However, their roles in the late tooth formation, such as cellular differentiation and matrix formation are not clearly understood. The objective of this study is to understand the roles of Smad4 in vivo during enamel and dentin formation through tissue-specific inactivation of Smad4. Methods: We generated and analyzed mice with dental epithelium-specific inactivation of the Smad4 gene (K14-Cre:$Smad4^{fl/fl}$) and dental mesenchyme-specific inactivation of Smad4 gene (Osr2Ires-Cre:$Smad4^{fl/fl}$). Results: In the tooth germs of K14-Cre:$Smad4^{fl/fl}$, ameloblast differentiation was not detectable in inner enamel epithelial cells, however, dentin-like structure was formed in dental mesenchymal cells. In the tooth germs of Osr2Ires-Cre:$Smad4^{fl/fl}$ mice, ameloblasts were normally differentiated from inner enamel epithelial cells. Interestingly, we found that bone-like structures, with cellular inclusion, were formed in the dentin region of Osr2Ires-Cre:$Smad4^{fl/fl}$ mice. Conclusion: Taken together, our study demonstrates that Smad4 plays a crucial role in regulating ameloblast and odontoblast differentiation, as well as in regulating epithelial-mesenchymal interactions during tooth development.

• 대한소아치과학회지
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• 제38권3호
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• pp.290-295
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• 2011

치아형성 과정 중 치배 주위의 물리적 작용이나 대사 환경의 변화로 치아 발생은 영향을 받을 수 있다. 유치열기에 가해진 외상은 계승 영구치의 발생에 장애를 초래시킬 수 있는 가장 대표적인 물리적 요인으로 이로 인한 합병증으로 계승 영구치의 법랑질 변색 및 저형성증이 가장 흔히 발생하고 드물게 매복, 이소 맹출, 치근 형성 정지 및 치근 만곡 등이 나타난다. 본 증례에서는 만 6세 5개월의 여자 어린이 환자가 안면부 외상을 주소로 내원하여 상악 좌우 유중절치의 정출성 탈구, 상악 우측 유측절치의 함입성 탈구, 상악 좌측 유측절치의 구개측 측방 탈구로 진단되었고, 상악 치은부의 열상과 상악 전치부의 치조골 골절이 관찰되었다. 내원 당일 치과 응급실에서 동요도가 심한 상악 좌우 유중절치의 발치 후 치은 봉합술을 시행하였다. 24개월 정기 검진 중 방사선 사진 상에서 상악 좌,우측 측절치의 백악 법랑 경계(Cemento enamel junction, CEJ) 근방에 치근 만곡이 관찰되었고 상악 중절치 치근의 치관부 1/3부위에서 치근 형성이 정지되고 있는 양상이 관찰되었다. 치조골 골절이 어린이에서 흔하게 나타나는 외상의 유형은 아니나 본 증례에서와 같이 치근 발육이상 등 여러 합병증을 일으킬 수 있으므로 외상을 입은 환아에서 치조골 골절 여부에 대한 면밀한 검사 및 주기적인 검진은 예후 예측 및 향후 치료에 있어서 중요할 것이다.

• 대한소아치과학회지
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• 제24권4호
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• pp.776-780
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• 1997

Patient with alveolar abscess due to dental caries with severe alveolar bone loss, severe tooth mobility, root resorption need extraction of tooth because it is impossible to carry out pulp treatment and restoration by using conventional method. Early loss of primary molar might cause masticatory interference, extrusion of opposing tooth, problem in maintaining space and interference on eruption of permanent tooth. Especially, early loss of primary second molar before the eruption of permanent first molar might cause space closure by mesially erupted permanent first molar and impaction of second premolar. In such a case, distal shoe space maintainer and removable space regaining appliance was the first choice of treatment. But, distal shoe space maintainer need precise adaptation and might cause chronic inflammation if the oral hygiene is poor. In a case using removable space regaining appliance, patient's cooperation is most important. If the distal root of primary second molar is comparably sound and alveolar abscess with alveolar bone loss is localized at mesial root, hemisection should be carried out for precise guide to eruption of the permanent first molar, restoration of masticatory fuction and solution to the discomfort of the patient

• Restorative Dentistry and Endodontics
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• 제43권2호
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• pp.17.1-17.7
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• 2018

Iatrogenic perforations negatively impact the outcome of endodontic treatments. Studies on prognostic factors showed that perforations in the coronal third of the root with periodontal pocket formation have an unfavorable prognosis. A 36-year-old female was referred for endodontic evaluation of tooth #13 with a history of an iatrogenic perforation, happened 3 years ago. There was a sinus tract associated with perforation, 10 mm probing on the mesial and mesio-palatal, bleeding on probing, radiolucent lesion adjacent to the perforation and complete resorption of the interdental bone between teeth #13 and #12. After the treatment options were discussed, she chose to save the tooth. The tooth was accessed under rubber dam isolation, the perforation site was cleaned and disinfected using 0.5% sodium hypochlorite and sealed with calcium-enriched mixture cement. Eighteen months after treatment the tooth was functional and asymptomatic. The probing depths were normal without bleeding on probing. Radiographically, the interdental crestal bone formed between teeth #13 and #12. Despite all negative prognostic factors in this case (i.e., perforations in the coronal third, pocket formation, and radiolucent lesion), healing was unexpectedly achieved via non-surgical repair of the perforation. Further research on biological aspects of healing in the periodontium following iatrogenic perforations are recommended.

• 대한치과교정학회지
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• 제46권6호
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• pp.379-385
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• 2016

Objective: Forced eruption has been proposed for the reconstruction of deficient bone and soft tissue. The aim of this study was to examine the changes in the alveolar ridge width and the vertical levels of the interproximal bone and papilla following forced eruption. Methods: Patients whose hopeless maxillary anterior teeth were expected to undergo severe bone resorption and soft tissue recession upon extraction were recruited. In addition, patients whose maxillary anterior teeth required forced eruption for restoration due to tooth fracture or dental caries were included. Before and after forced eruption, the interproximal bone height was measured by radiographic analysis, and changes in the alveolar ridge width and the interproximal papilla height were measured with an acrylic stent. Results: This prospective study demonstrated that the levels of the interproximal alveolar bone and papilla were significantly increased by 1.36 mm and 1.09 mm, respectively, in the vertical direction. However, the alveolar ridge width was significantly reduced by an average of 0.67 mm in the buccolingual direction. The changes in the level of the interproximal alveolar bone and papilla were positively correlated. Conclusions: Although the levels of the interproximal bone and papilla were significantly increased, the alveolar ridge width was significantly decreased following forced eruption. There was a modest positive and significant correlation between the changes in the height of the interproximal alveolar bone and the papilla. Based on our findings, modification of vertical forced eruption should be considered when augmentation of the alveolar ridge width is required.