• 대한치과교정학회지
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• 제30권2호
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• pp.261-272
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• 2000

심한 골격성 전후방 및 수직적 악골 부조화를 동반하는 경우는 교정치료 만으로는 만족할 만한 결과를 얻기 어렵고 많은 전후방적인 이동과 치료의 안정성을 얻기 위하여 교정치료와 동반한 악교정수술이 필요하다. 하악전돌증 환자에서의 치료의 목적은 저작, 발음 등 악구강계의 기능을 개선하고 안모의 심미성을 증진시키는 한편 안정성을 유지하는 데에 있다. 악교정수술에 의한 하악골의 이동으로 위치의 변화를 보이는 조직으로는 설골, 인두, 혀 등이 있다. 악교정수술을 동반한 교정치료를 받은 골격성 하악전돌증 환자에서 주위 조직들에서 변화 양상을 관찰하고 악교정수술 전후와 보정기간 후의 회귀나 재발에 의한 설골, 인두, 혀 및 상하순의 변화를 살펴보기 위하여 본 연구를 시행하였다. 본 연구에서는 하악전돌증을 주소로 내원하여 하악상행지 시상골절단술을 동반한 교정치료를 받은 환자 22명의 측모두부방사선 규격사진을 수술 전 (T1),수술 후 (T2), 교정장치의 제거 2년 보정 후 (T3) 3회에 걸쳐 계측 및 비교한 후 다음과 같은 결과를 얻었다. 1. 수술 후 설골이 상악골 및 교합평면에 대해 시계방향으로 회전하였으며 보정기간 후 회귀함을 보여주었다. 2. 하악골의 수술에 의한 후방이동 후 설골이 후하방으로 이동하였으며 보정기간 후 상전방으로 회귀함을 보여주었다. 3. 인두의 깊이 변화는 상부에서 수술직후 약간 감소하는 경향을 보여 주었으나 보정 전후에 전반적으로 유의한 차이가 없는 것으로 나타났다. 4. 혀의 기저부와 관련해서는 혀 기저부 각 (Cv4ia-hy-pt)이 감소하고, 혀의 기저부 배면이 후하방으로 변화하는 양상을 보여주었으며 보정기간 후에 상방으로 변화하였다. 5. 상하순의 두께는 상순에서는 수술 후 감소하였다가 다시 증가하는 양상을, 하순이하의 연조직에서 두께가 증가하였다가 감소하는 형태로 나타났다. 이는 하순에서는 수술 후 잉여 연조직에 의한 두께의 증가가 나타나고 상순에서는 구륜근에 의한 장력에 의해 상순의 두께가 감소하였다가 보정 기간 후 새로운 악골 위치로 적응하는 것으로 생각된다.

• Childhood Kidney Diseases
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• 제8권2호
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• pp.195-204
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• 2004

목적: 저인산혈성 구루병 환아의 임상상, 각종 혈액화학 검사 수치 및 방사선 검사 소견, 치료에 대한 반응 등을 살피고 효과적인 치료에 도움이 되는 정보를 얻고자 본 연구를 시행하였다. 방법: 1983년 7월부터 2004년 2월까지 서울대학교병원 소아과에서 저인산혈성 구루병으로 진단받고 내과적인 치료를 받은 환아들의 의무기록지를 후향적으로 분석하였다. 결과: 대상환자는 56명이었고, 남녀의 비는 1:3 이었다 주소는 대부분 하지만곡과 저신장이었고, 혼자 걷기 시작하면서 발견된 경우가 가장 많았다. 진단시 평균연령은 5년 2개월 이었으며 12개월 이전에 진단 받은 경우는 없었다. 14명(25%)에서 가족력이 있었다. 진단받은 연령과 신장의 표준편차 점수는 통계적으로 의미있는 음의 상관관계가 있었다(r=-0.47, p=0.005). 생화학적 검사에서 정상 혈청 칼슘, 혈청 인의 저하, alkaline phosphatase의 상승, 세뇨관에서 인산 재흡수의 감소 및 정상 범위의 $1,25(OH)_2D_3$ 치를 보였다. 방사선 검사는 구루병에 합당하였다. 치료제로 Joulie 용액과 비타민 D 대사체를 복용하였다. 치료를 시작한 후 혈청 인과 alkaline phosphatase는 통계적으로 의미있는(P<0.05) 호전을 보였고, 방사선 검사는 구루병의 치유를 보였으나, 신장 표준편차 점수는 의미있는 변화를 보이지 않았다(.p=0.224). 치료의 부작용으로 신석회화(34%), 부갑상선호르몬의 상승(77%), 고칼슘뇨증(45%) 등이 발생하였다. 16명이 절골술을 통한 변형의 교정을 시행하였고, 그 중 4명은 하지연장을 함께 시행하였다. 결론: 증상의 시작과 진단 사이에는 수 년간의 지연이 있었다 조기치료가 환자의 예후에 가장 중요하므로, 가족력이 있는 경우 증상 발현 이전에 생화학적 검사로 조기 진단 및 치료를 하도록 해야 한다. 치료 중에는 정기적인 모니터링과 용량의 조절을 통해 합병증에 대처해야 한다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제28권6호
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• pp.531-548
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• 2006

The purpose of this study was to investigate the biomechanical, histologic findings of distracted regenerate and TMJ response in modified distraction osteogenesis (DO) technique combined with compression force as biomechanical stimulation method which has been suggested in 2002, and developed thereafter by authors. This study was performed with two experiments. First experiment was designed to explore the optimal ratio of compression force versus distraction force for the new DO technique. Second experiment was planned to evaluate the reaction of TMJ tissue, especially condyle, disc after application of the DO technique with compression force. Total 52 New Zealand adult male-rabbits with 3.0kg body weight were used for the study. For the first study, 30 adult male-rabbits underwent osteotomy at one side of mandibular body and a external distraction device was applied on each rabbit with same manner. In the control group of 10 rabbits, final 8 mm of distraction with 1 mm rate per day was done with conventional DO technique after 5 latency days. For the experimental group of 20 rabbits, a compression force with 1 mm rate per day was added to the distracted mandible on 3-latency day after over-distraction (over-lengthening). As the amount of the rate of compression versus distraction, experimental subgroup I (10 rabbits) was set up as 2 mm compression versus 10 mm distraction (1/5) and experimental subgroup II (10 rabbits) was set up as 3 mm compression versus 11 mm distraction (about 1/3). All 30 rabbits were set up to obtain final 8 mm distraction and sacrificed on postoperative 55 day to analysis on biomechanical, and histologic findings of the bone regenerates. For second study, 22 adult male-rabbits were used to evaluate TMJ response after the DO method application with compression force. In the control group, 10 rabbits was used to be performed with conventional DO method, on the other hand, in a experimental group of 10 rabbits, 10 mm distraction with 2 mm compression (1/5 ratio) was done. The remaining 2 rabbits served as the normal control group. Histomorphologic examinations on both condyle, histological studies on condyle, disc were done at 1, 2, 3, 4, 7 weeks after distraction force application. The results were as follows: 1. On the bone density findings, the experimental group II (force ratio - 1/3) showed higher bone density than the other experimental group (force ratio - 1/5) and control group (control group - $0,2906\;g/cm^2$, experimental group I - $0.2961\;g/cm^2$, experimental group II - $0.3328\;g/cm^2$). 2. In the histologic findings, more rapid bone maturation like as wide lamellar bone site, more trabeculae formation was observed in two experimental groups compared to the conventional DO control group. 3. In morphologic findings of condyle, there were no differences of size and architecture in the condyle in the control and experimental groups. 4. In histologic findings of condyles, there were thicker fiberous and proliferative layers in experimental group than those of control group until 2 weeks after distraction with compression force. But, no differences were seen between two groups on 3, 4, 7 weeks after compression. 5. In histologic findings of disc, more collagen contents in extracellular matrix, more regular fiber bundles, and less elastin fibers were seen in experimental group than control group until 2 weeks after distraction with compression. But, no differences were seen between two groups on 3, 4, 7 weeks after distraction with compression. From this study, we could identify that the new distraction osteogenesis technique with compression stimulation might improve the quality of bone regeneration. The no remarkable differences on TMJ response between control and experimental groups were seen and TMJ tissues were recovered similarly to normal TMJ condition after 3 weeks.

• Clinics in Shoulder and Elbow
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• 제15권2호
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• pp.130-137
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• 2012

목적: 골다공증이 있는 노인환자에서 상완골 원위부 관절부위 골절로 관혈적 정복술 및 내고정술과 주관절 전치환술 시행 후 기능적 결과에 대해서 평가 보고하였다. 대상 및 방법: 2007년1월부터 2009년 10월까지 상완골 원위부 관절내 골절을 주소로 내원한 65세 이상의 환자 24명을 대상으로 하였으며 18명은 후방 도달법을 이용하여 관혈적 정복술 및 내고정술을 시행하고 (Fig. 1), 6명은 주관절 전치환술을 시행하였다 (Fig. 2). 평균 추시 기간은 16.3 개월 이였으며 골절형태는 AO 분류로 8명이 C2, 16명이 C3 형태의 골절이였다. 추시 시 모든 환자들은 방사선촬영 및 신체검사를 시행하였고, Mayo 주관절 수행점수, 및 DASH 점수를 이용하여 임상적 결과를 측정하였다. 결과: Group I 18예 모두 골유합 되었으며 골절부터 골유합까지 평균 기간은 14주였다. 합병증으로 2예에서 주두골 절골부위에 불유합이 관찰되었으며 척골신경증상을 보였던 2예 중 1예는 전방이전술에도 불구하고 개선되지 않았다. Mayo 주관절 수행점수는 평균 87.0점이였으며, DASH 점수는 평균 32.4점이였다. 마지막 추시 시에 시행한 이학적 검사에서 굴곡은 평균 121.0도 (95~145도), 굴곡구축은 평균 12도 (0~35)이였다. Group II 6예 모두 추시 기간내 합병증은 없었으며, Mayo 주관절 수행점수는 평균 89.1점 이였으며, DASH 점수는 평균 44.3점이었다. 마지막 추시 시에 시행한 이학적 검사에서 굴곡은 평균 125.1도 (100~145도), 굴곡 구축은 평균 12.6도 (0~30)이였다. 결론: 골다공증을 동반한 고령의 상완골 원위부 관절내 골절 환자에서 적절한 환자 선택시 내고정술 뿐만 아니라 전치환술에서도 단기 추시 시 만족할만한 결과를 보임을 확인할 수 있었다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권4호
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• pp.299-305
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• 2010

Purpose: Adipose tissue is located beneath the skin, around internal organs, and in the bone marrow in humans. Its main role is to store energy in the form of fat, although it also cushions and insulates the body. Adipose tissue also has the ability to dynamically expand and shrink throughout the life of an adult. Recently, it has been shown that adipose tissue contains a population of adult multipotent mesenchymal stem cells and endothelial progenitor cells that, in cell culture conditions, have extensive proliferative capacity and are able to differentiate into several lineages, including, osteogenic, chondrogenic, endothelial cells, and myogenic lineages. Materials and Methods: This study focused on endothelial cell culture from the adipose tissue. Adipose tissues were harvested from buccal fat pad during bilateral sagittal split ramus osteotomy for surgical correction of mandibular prognathism. The tissues were treated with 0.075% type I collagenase. The samples were neutralized with DMEM/and centrifuged for 10 min at 2,400 rpm. The pellet was treated with 3 volume of RBC lysis buffer and filtered through a 100 ${\mu}m$ nylon cell strainer. The filtered cells were centrifuged for 10 min at 2,400 rpm. The cells were further cultured in the endothelial cell culture medium (EGM-2, Cambrex, Walkersville, Md., USA) supplemented with 10% fetal bovine serum, human EGF, human VEGF, human insulin-like growth factor-1, human FGF-$\beta$, heparin, ascorbic acid and hydrocortisone at a density of $1{\times}10^5$ cells/well in a 24-well plate. Low positivity of endothelial cell markers, such as CD31 and CD146, was observed during early passage of cells. Results: Increase of CD146 positivity was observed in passage 5 to 7 adipose tissue-derived cells. However, CD44, representative mesenchymal stem cell marker, was also strongly expressed. CD146 sorted adipose tissue-derived cells was cultured using immuno-magnetic beads. Magnetic labeling with 100 ${\mu}l$ microbeads per 108 cells was performed for 30 minutes at $4^{\circ}C$ a using CD146 direct cell isolation kit. Magnetic separation was carried out and a separator under a biological hood. Aliquous of CD146+ sorted cells were evaluated for purity by flow cytometry. Sorted cells were 96.04% positivity for CD146. And then tube formation was examined. These CD146 sorted adipose tissue-derived cells formed tube-like structures on Matrigel. Conclusion: These results suggest that adipose tissue-derived cells are endothelial cells. With the fabrication of the vascularized scaffold construct, novel approaches could be developed to enhance the engineered scaffold by the addition of adipose tissue-derived endothelial cells and periosteal-derived osteoblastic cells to promote bone growth.

• 대한치과교정학회지
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• 제29권1호
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• pp.113-127
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• 1999

악골의 골격적 부조화를 가진 환자의 교정치료는 악교정 수술을 필요로 하고, 악교정 수술에 의해 교합평면각은 변화된다. 특히 전치부 개교를 동반한 III급 부정교합 환자에서 치아안면 기형을 치료하기 위한 교합평면각의 변화에 대하여 많은 논란이 있어 왔다. 교합평면각을 증가시키는 하악골의 시계 방향 회전(clockwise rotation)은 전치부 개교에 대한 적절한 치료법으로 추천되어 왔고 하악골의 반시계 방향의 회전(counterclockwise rotation)은 하악지 고경을 증가시키는 방향으로 하악골을 회전시킨다는 개념으로 인해 재발(relapse)을 유발하는 불안정한 수술 방법으로 인식되어 왔다. 본 연구는 전치부 개교를 동반한 골격성 III 부정교합 환자에서 교합평면의 반시계 방향 회전을 동반한 하악지 시상분할 골절단술 시행 후 교합평면각의 변화와 술후 안정성과의 관계를 평가 하고자 하였다. 하악지 시상분할 골절 단술과 rigid fixation으로 치료받은 환자 25 명 (평균연령 20.6세)을 대상으로 하여 수술 직전(T1), 술후 2주내(T2), 그리고 술후 6 개월 이후(T3)에 촬영한 측모 두부계측 방사선 사진을 통계분석한 결과(Paired t-test, Pearson correlation analysis), 다음의 결론을 얻었다. 1. 악교정 수술 후(T2) 하악평면각은 $2.9^{\circ}$ 감소하였고 SN 평면에 대한 하악 교합평면의 각도는 $2.7^{\circ}$ 감소하였다. 술후 6 개월경과 후(T3) 후안면 고경의 감소로 인해(P<0.01) 하악 평면각은 $1.0^{\circ}$ 증가하였으나 하악 교합평면의 경사도는 변화되지 않았다. 2. 악교정 수술 후 시간 경과(T3)에 의해 발생한 수평적 재발은 하악골의 전방 이동량이 B점에서 1.6 mm로 수술시 전체 후방 이동량의 약$22\%$였다. 전안면 고경에서는 수직적 재발이 발생하지 않았으나,후안면 고경은 감소하였다. (P<0.01). 3. 수평적 재발과 상관관계를 보이는 항목은 하악평면각 이었고(P<0.01) 수술 6 개월경과 후 후안면 고경의 감소와 상관관계가 있는 요소로는 수술시 하악골의 후방 이동량(P<0.01), 하악지 고경의 증가량(P<0.01), 그리고 하악평면각의 감소량(P<0.01) 등이 있었다. 4. 수술시 하악 교합평면 경사도의 변화량과 술후 재발과는 상관관계가 없었다.

• 대한치과보철학회지
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• 제51권1호
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• pp.11-19
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• 2013

연구 목적: 본 연구에서는 수술가이드를 이용한 무피판 임플란트 술식에서 임플란트 드릴링이 열발생에 미치는 효과를 측정하였으며 드릴링 방법에 따른 온도 차이를 측정하고자 하였다. 연구 재료 및 방법: 하악 양측 제 1 대구치와 제 2 대구치가 없는 실험 모델에서 피판을 거상하는 임플란트 수술(실험A군)과 수술가이드를 이용한 무피판 임플란트 수술(실험B군), 그리고 핸드피스의 상하 수직 움직임을 제한한 후 수술가이드를 이용하여 무피판 임플란트 수술(실험C군)을 각각 진행하여 온도 측정을 하였다. 임플란트 드릴링 시 온도 측정은 thermocouple과 열전식 온도 기록계(Yokogawa, Tokyo, Japan)를 이용하여 측정하였다. 온도 측정 위치는 최종 임플란트 드릴(직경 3.8 mm)의 경계부에서 0.5 mm 떨어진 곳에서 3 mm 깊이(설측)와 6 mm 깊이(협측)로 하였다. 측정된 온도 값을 이용하여 종속변수인 온도가 정규분포 하는지를 검정하기 위해 Kolmogorov-Smirnov test를 거쳐 확인한 후 세 수술 방법 간의 평균 온도 차이를 검정하기 위해 independent t-test로 분석하였다. 결과: 피판을 거상하고 드릴링을 한 수술군(실험A군)에서 평균 온도는 $27.2^{\circ}C$($SD{\pm}2.1^{\circ}C$)를 보였고 피판을 거상하지 않고 드릴링을 한 수술군(실험B군)에서 평균 $27.5^{\circ}C$($SD{\pm}2.3^{\circ}C$)를 나타냈다. 이들 두 수술 방법 간 온도비교에서는 통계학적으로 유의한 차이를 보이지 않았다. 수술가이드를 이용하여 무피판 수술 시 상하 수직 움직임(upand-down pumping motion)이 없이 드릴링을 시행한 수술군(실험C군)에서 평균온도는 $37.0^{\circ}C$($SD{\pm}3.4^{\circ}C$)을 보였다. 이를 상하 수직 움직임으로 드릴링을 한 무피판 임플란트 수술군(실험B군)과 비교 시 통계학적으로 유의한 온도 차이를 보였다. 결론: 수술가이드를 이용하여 무피판 임플란트 수술 시 핸드피스를 상하 수직 움직임으로 드릴링을 시행하면 피판을 거상하여 수술할 때와 온도차이가 발생하지 않으나, 상하 수직 움직임 없이 드릴링을 시행하면 드릴링 시 높은 온도 상승을 보인다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제27권5호
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• pp.403-414
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• 2005

The purpose of this study was to identify the effectiveness of the modified distraction osteogenesis (DO) method with the concept of overdistraction and compression stimulation which have been previously suggested by the authors in 2002 and to explore the optimal distraction-compression ratio and appropriate latency period for the compression force application during consolidation. The experimental specimens were assessed with radiography, histologic findings, and dual energy x-ray absorptiometry (DEXA) after the conventional DO method and the modified DO technique had been applied on rat mandibles. Total 60 rats were used for the study. In experimental group of 54 adult rats, mandibular osteotomies between the first and second molar areas were performed and customized external distractors were applied. The surgeries on 6 rats of control group also were done with same osteotomy technique and DO device application. Final amount of distraction was set-up as 2 mm on both groups. But, in a experimental group of 54 rats, distraction osteogenesis with a compression force were performed with the different distraction-compression ratio and variant latency periods for compression. The three ratio-subgroups were made as distraction 4 mm group with compression 2 mm, distraction 3 mm group with compression 1 mm, and distraction 2.5 mm group with compression 0.5 mm. In addition, The three subgroups with 3, 7, 11 days latency period prior compression were allocated on each ratio-subgroups. Total 9 subgroups consisted of 6 rats on each subgroup. In control group of 6 rats, conventional distraction technique were routinely performed. The rats of control groups were sacrificed on postoperative 3, 6 weeks after 2 mm distraction. The rats in the experimental groups also were sacrificed on the same euthanasia days of control groups to compare the wound healing. Final available specimens were 55 rats except 5 due to osteomyelitis, device dislodgement. Distraction-compression combined group on 6 weeks generally had showed increased bone mineral density than the same period group of conventional distraction technique on the DEXA study. More matured lamellar bone state and extended trabecular pattern in the combined group than those of control group were also observed in the histologic findings on 6 weeks. In the distraction-compression combined groups, the bone density of 2.5 mm distraction subgroups with 0.5 mm compression showed the highest value on the DEXA study among various force ratio groups. In the distraction-compression combined groups, the bone density of 3 day latency period subgroups showed the highest value on the DEXA study among various latency period groups for the compression application. From this study, we could deduce that 1/5 force ratio for the compression versus distraction, 3 day latency period prior compression application would be the most effective condition if modified distraction osteogenesis technique might be applicable. The modified DO method with a compression force may improve the quality of bone regenerate and shorten total treatment period in comparison with conventional DO technique clinically.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제33권2호
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• pp.152-161
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• 2007

This study was conducted to patients visited oral maxillo-facial surgery, KNUH and the purpose of the study was to assess skeletal and dento-alveolar stability after surgical-orthodontic correction treated by skeletal Class III malocclusion patients with open bite versus non-open bite. This retrospective study was based on the examination of 40 patient, 19 males and 21 females, with a mean age 22.3 years. The patients were divided into two groups based on open bite and non-open bite skeletal Class III malocclusion patients. The cephalometric records of 40 skeletal Class III malocclusion patients (open bite: n = 18, non-open bite: n = 22) were examined at different time point, i.e. before surgery(T1), immediately after surgery(T2), one year after surgery(T3). Bilateral sagittal split ramus osteotomy was performed in 40 patients. Rigid internal fixation was standard method used in all patient. Through analysis and evaluation of the cephalometric records, we were able to achieve following results of post-surgical stability and relapse. 1. There was no significant statistical differences between open bite and non-open bite with skeletal Class III malocclusion patients in maxillary occlusal plane angle of pre-operative stage(p>0.05). 2. Mean vertical relapses of skeletal Class III malocclusion patients with open bite were $0.02{\pm}1.43mm$ at B point and $0.42{\pm}1.56mm$ at Pogonion point. In skeletal Class III malocclusion patients with non-open bite, $0.12{\pm}1.55mm$ at B point and $0.08{\pm}1.57mm$ at Pogonion point. There was no significant statistical differences between open bite and non-open bite with skeletal Class III malocclusion patients in vertical relapse(p>0.05). 3. Mean horizontal relapses of skeletal Class III malocclusion patients with open bite were $1.22{\pm}2.21mm$ at B point and $0.74{\pm}2.25mm$ at Pogonion point. In skeletal Class III malocclusion patients with non-open bite, $0.92{\pm}1.81mm$ at B point and $0.83{\pm}2.11mm$ at Pogonion point. There was no significant statistical differences between open bite and non-open bite with skeletal Class III malocclusion patients in horizontal relapse(p>0.05). 4. There were no significant statistical differences between open bite and non-open bite with skeletal Class III malocclusion patients in post-surgical mandibular stability(p>0.05). and we believe this is due to minimized mandibular condylar positional change using mandibular condylar positioning system and also rigid fixation using miniplate 5. Although there was no significant relapse tendency observed at chin points, according to the Pearson correlation analysis, the mandibular relapse was influenced by the amount of vertical and horizontal movement of mandibular set-back(p=0.05, r>0.304).

• Maxillofacial Plastic and Reconstructive Surgery
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• 제28권5호
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• pp.404-416
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• 2006

Purpose : This study was to clarify the changes in mandibular condyle after unilateral mandibular distraction osteogenesis throughout histological changes and expression of matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of matrix metalloproteinase-2 (TIMP-2). Materials & Methods : Intraoral distractors were placed via submandibular incision in 8 dogs. Two unoperated animals served as controls. Distraction was performed five days after osteotomy as a rate of 0.5 mm twice per day for 10 days. Two animals were sacrificed on 7, 14, 28, and 56 days after completion of distraction, respectively. Ipsilateral condyles were harvested and processed for histological and immunohistochemical examinations. Results : The condyle cartilage is separated into four layers: fibrous layer, proliferative layer, hypertrophic layer, and calcified layer. At 7 days and 14 days after distraction, the condylar cartilage showed the decreased thickness of the articular cartilage and reduced cellularity. At 28 days after distraction, there was an increase in cellularity of fibrous, proliferative, and hypertrophic layer. However, it demonstrated reduced cellularity compared to the control. At 56 days of after distraction, the articular cartilage was an almost normal histologic structure. Positive Safranin-O staining, indicative of sulfated proteoglycans, was examined in the condylar cartilge of nonloaded control. At 7 days and 14 days after distraction, the sulfated proteoglycans is almost completely depleted from the noncalcified part of the condylar cartilage. At 28 days after distraction, there was an increase in Safranin-O staining intensity. However, the staining intensity of the experimental condyle was weaker than that of the control. At 56 days of after distraction, the condylar cartilage showed almost normal Safranin-O staining pattern. In control condyle, MMP-2 immunostaining was seen in fibrous, proliferative, and hypertrophic layer of condylar cartilage, however, it demonstrated lack of staining in fibrous and proliferative layer. At 7 days and 14 days after distraction, strong MMP-2 immunoreactivity was seen in the fibrous, proliferative and hypertrophic layer of the condylar cartilage. At 28 days after distraction, MMP-2 immunostaining was seen in the fibrous and hypertrophic layer of condylar cartilage, however, their immunoactivity was reduced. At 56 days after distraction, MMP-2 immunoreactivity showed almost normal immunostaining pattern. In control condyle, TIMP-2 immunostaining was primarily seen in fibrous and hypertrophic layer of condylar cartilage, however, it demonstrated lack of staining in proliferative layer. At 7 days after distraction, very weak TIMP-2 immunoreactivity appeared in fibrous, proliferative and hypertrophic layer of the condylar cartilage. At 14 days after distraction, weak TIMP-2 immunoreactivity was seen in the fibrous, proliferative and hypertrophic layer of the condylar cartilage. At 28 days after distraction, TIMP-2 immunoreactivity was increased in the fibrous and hypertrophic layer of condylar cartilage. At 56 days after completion of distraction, TIMP-2 immunoreactivity showed almost normal immunostaining pattern. Conclusions : The results show that short-term outcome of physiologic distraction osteogenesis may lead to degenerative changes in the condylar cartilage. These alterations in the condylar cartilage may be considered as a pressure-related degeneration of the cartilage tissue. However, the long-term results suggest that the condylar cartilage display repair activity after mandibular distraction osteogenesis.