• Title/Summary/Keyword: 골 용해

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Temporary replacement of congenital missing incisors on mandible using temporary anchorage devices in growing patient: 2-year follow-up (성장기 아동에서 교정용 골성 고정원을 이용한 선천 결손 하악 전치의 임시 보철 수복: 2년 경과 관찰)

  • Choi, Youn-kyung;Kwon, Eun-Young;Jung, Kyung-Hwa;Choi, Na-Rae;Park, Soo-Byung;Kim, Seong-sik;Kim, Yong-il
    • Journal of Dental Rehabilitation and Applied Science
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    • v.36 no.4
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    • pp.272-281
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    • 2020
  • Agenesis of permanent tooth in adolescent patients can be treated either by orthodontic treatment for space closure or by maintaining the space until implant restoration can be carried out in adult. However, gradual atrophy of alveolar bone width makes it difficult to restore the prosthesis in the future or may cause unaesthetic results. Therefore, maintaining of not only the missing space but also the alveolar bone width should be considered. This case is a treatment whereby a temporary replacement of missing 2 mandibular incisors in adolescent patient was carried out using 2 temporary anchorage devices (TADs). Two TADs were placed horizontally 2 - 3 mm below the top of alveolar ridge, and fixed with artificial teeth by stainless steel wires extended. During the 2 year follow-up, neither gingival inflammation nor loss of the TADs have occurred. In the radiographic evaluation, the growth of the adjacent alveolar bone was not inhibited, and the width of the alveolar bone was maintained.

Implant-supported fixed prosthetic restoration using a high performance polymer (PEKK) in a mandibular unilateral resection: A case report (하악골 편측 절제 환자에서 High Performance Polymer (PEKK)를 이용한 임플란트 지지형 고정성 보철 수복 증례)

  • Kong, Dae-Ryong;Min, Gyeong-Won;Jang, Ki-Yeol;Lee, Gyeong-Je;Lee, Sun-Haeng
    • The Journal of Korean Academy of Prosthodontics
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    • v.60 no.3
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    • pp.254-262
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    • 2022
  • When treating partial edentulous patients, it is important to use an appropriate restorative materials. Inappropriate restorative materials can adversely affect the outcome of prosthetic restorations. Zirconia and dental metal, which are currently and widely used materials, have a higher elastic modulus than cortical bone, so when an external force is generated, a harmful force can be applied to the implant and the bone around the implant. Polyetherketoneketone (PEKK), a recently introduced material, has a elastic modulus similar to that of cortical bone, and has many advantages in terms of physical properties and biocompatibility. This case report describes that implant-supported fixed prosthetic treatment using PEKK was performed, and functional and esthetic satisfactory results were obtained.

Role of Lymphatic Embolization in Chylothorax Associated with Gorham-Stout Disease: A Case Report (고함-스타우트병과 연관된 유미흉 치료에서 림프관 색전술의 역할: 증례 보고)

  • Min-Hyuk Yu;Dongho Hyun;Sun-Hye Shin;Sang-Yun Ha
    • Journal of the Korean Society of Radiology
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    • v.85 no.2
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    • pp.451-455
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    • 2024
  • A 45-year-old male patient with spontaneous chylothorax and osteolysis in the right 1st and 2nd ribs was diagnosed with Gorham-Stout disease based on clinical manifestations and bone biopsy. The chylothorax temporarily decreased after a successful selective lymphatic embolization. The patient presented with recurrent chylothorax, mild chest discomfort, and progressive osteolysis (despite administering sirolimus) during the follow-up period of 15 months.

Grade I and II Chondrosarcoma of the Humerus (상완골에서 발생한 Grade I 및 Grade II 연골육종 - 증례 보고 -)

  • Cho, Wan-Hyeong;Jeon, Dae-Geun;Park, Jong-Hoon;Song, Won-Seok;An, Joon-Hwan;Lee, Soo-Yong
    • The Journal of the Korean bone and joint tumor society
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    • v.12 no.2
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    • pp.131-135
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    • 2006
  • Chondrosarcoma can be divided into grade I, II and III by histological finding and a relationship between the prognosis and the histological grading has been identified. Although the surgical treatment of grade II and III chondrosarcoma necessitates wide resection margin, there has been controversy about curettage versus wide resection in case of grade I chondrosarcoma. The authors report a case of grade I chondrosarcoma of proximal humerus and grade II chondrosarcoma of distal humerus with good oncological and functional result through curettage and wide resection respectively.

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Investigation of osseointegration according to the healing time after having iatrogenic mobility of implant fixtures (임플란트 고정체의 인위적 비틀림 후 시간 경과에 따른 골재유착 반응에 관한 연구)

  • Hwang, Yun-Jin;Cho, Jin-Hyun;Lee, Cheong-Hee
    • The Journal of Korean Academy of Prosthodontics
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    • v.48 no.4
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    • pp.308-314
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    • 2010
  • Purpose: The purpose of this study is to analyze the change in re-osseointegration over time and bone reaction at the interface between implant fixture and the surface of the bone, after destroying re-osseointegration by distorting the bone-implant interface artificially. Materials and methods: Experimental implant fixtures (cp titanium, ${\phi}3.75\;mm{\times}4\;mm$) which didn't have surface treatment were produced. Two or three fixtures were implanted on both tibias of twelve female rabbits (New Zealand white, more than 3.5 kg). Then after six weeks, removal torque (RT) was measured and the results were recorded as the first measurement values. The fixtures were submerged again to get reosseointegration between the bone and fixture. To identify the change in re-osseointegration of submerged fixtures over time, six groups had the healing time for four days (group I), one week (group II), two weeks (group III), three weeks (group IV), four weeks (group V) and five weeks (group VI), and then the secondary removal torque was measured for each group. To identify the bone formation under fluorescent light, tetracycline (15 mg/kg, IM) were treated on the rabbits of each group. After the second measurement, the rabbits were sacrificed, and 16 slides were made, two or three for each group. The slides were observed under the fluorescent light with light microscope. To find out the change in the secondary removal torque over the primary removal torque in progress of time, the averages of the increase rate of the primary and secondary torque removal force were calculated. Then, to find out if there were any critical differences between the primary removal torque and the secondary removal torque in each group and among the groups, the results were analyzed statistically by paired t- test, one-way ANOVA, and Duncan's Multiple Range Test. Results: In group I and II, secondary removal torque decreased, especially in group I. In group III, IV, V, and VI, secondary removal torque increased critically. Comparing the differences among the groups, the critical difference was shown between group I, II and group III, IV, V, VI. Mineralization at the interface between the bone and implant fixture was identified from the first week, and bone formation was shown more clearly from the second week. Conclusion: If the implant fixture remains unforced for a certain period of time after the fixture has had iatrogenic mobility, re-osseointegration occurs at the surface of the fixture, and for tibias of rabbits, higher re-osseointegration was obtained within two weeks.

Implant-supported milled bar overdenture with two implant surgical guides (두 개의 수술용 가이드와 Milled-bar를 이용한 임플란트 피개 의치 수복 증례)

  • Pill-Sang Yun;Sunjai Kim;Se-Wook Pyo;Jae-Seung Chang
    • The Journal of Korean Academy of Prosthodontics
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    • v.61 no.1
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    • pp.55-62
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    • 2023
  • For fully edentulous patients, implant-supported overdenture can be considered to enhance chewing efficiency and denture stability. Implant planning software can be used to fabricate a surgical guide for a more precise consideration of anatomic factors and prediction of the shape of definitive prosthesis. Though there are many possible attachments for implant overdenture, milled bar can be useful due to its splinting effect of implants and rigid support of overdenture. This report presents a case of implant-supported milled bar overdenture after guided implant surgery performed with two surgical guide that was fabricated before and after bone reduction.

Histologic and biomechanical characteristics of orthodontic self-drilling and self-tapping microscrew implants (Self drilling과 Self-tapping microscrew implants의 조직학적 및 생역학적인 비교)

  • Park, Hyo-Sang;Yen, Shue;Jeoung, Seong-Hwa
    • The korean journal of orthodontics
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    • v.36 no.4
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    • pp.295-307
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    • 2006
  • Objective: The purpose of this study was to compare the histological and biomechanical characteristics of self-tapping and self-drilling microscrew implants. Methods: 112 microscrew implants (56 self-drilling and 56 self-tapping) were placed into the tibia of 28 rabbits. The implants were loaded immediately with no force, light (100 gm), or heavy force (200 gm) with nickel-titanium coil springs. The animals were sacrificed at 3- and 5-weeks after placement and histologic and histomorphometric analysis were performed under a microscope. Results: All microscrew implants stayed firm throughout the experiment. There was no significant difference between self-drilling and self-tapping microscrew implants both in peak insertion and removal torques. Histologic examinations showed there were more defects in the self-tapping than the self-drilling microscrew implants, and newly formed immature bone was increased at the interface in the self-tapping 5-week group. There was proliferation of bone towards the outer surface of the implant and/or toward the marrow space in the self-drilling group. Histologically, self-drilling microscrew implants provided more bone contact initially but the two methods became similar at 5 weeks. Conclusion: These results indicate the two methods can be used for microscrew implant placement, but when using self-tapping microscrew implants, it seems better to use light force in the early stages.

Three-dimensional finite element analysis according to the insertion depth of an immediately loaded implant in the anterior maxilla (상악 전치부 즉시하중 임플란트의 식립 깊이에 따른 삼차원 유한요소 분석)

  • Park, Cheol-Woo;Kim, Sung-Hun;Yeo, In-Sung;Yoon, Hyung-In;Han, Jung-Suk
    • The Journal of Korean Academy of Prosthodontics
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    • v.56 no.2
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    • pp.105-113
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    • 2018
  • Purpose: The purpose of this study was to investigate the effects of the insertion depth of an immediately loaded implant on the stress distribution of the surrounding bone and the micromovement of the implant using the three-dimensional finite element analysis. Materials and methods: A total of five bone models were constructed such that the implant platform was positioned at the levels of 0.00 mm, 0.25 mm, 0.50 mm, 0.75 mm, and 1.00 mm depth from the crest of the cortical bone. A frictional coefficient of 0.3 and the insertion torque of 35 Ncm were simulated on the interface between the implant and surrounding bone. A static load of 178 N was applied to the provisional prosthesis with a vertical load in the axial direction and an oblique load at $30^{\circ}$ with respect to the central axis of the implant, then a finite element analysis was performed. Results: The implant insertion depth significantly affected the stress distribution on the surrounding bone. The largest micromovement value of the implant was $39.34{\mu}m$. The oblique load contributed significantly to the stress distribution and micromovement in comparison to the vertical load. Conclusion: Increasing the implant insertion depth was advantageous in dispersing the concentrated stress in the cortical bone and did not significantly affect the micromovement associated with early osseointegration failure.

Three Dimensional Optimum Design of Endosseous Implant in Dentistry by Multilevel Optimization Method (다단계 최적화기법을 이용한 치과용 골내 임플란트의 3차원 형상최적설계)

  • 한중석;김종수;최주호
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2004.04a
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    • pp.143-150
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    • 2004
  • An optimum design problem for endosseous implant in dentistry is studied to find best implant design. An optimum design problem is formulated to reduce stresses arising at the cortical as well as cancellous bones, in which sufficient design parameters are chosen for design definition that encompasses major implants in popular use. Optimization at once (OAO) with the large number of design variables, however, causes too costly solution or even failure to converge. A concept of multilevel optimization (MLO) is employed to this end, which is to group the design variables of similar nature, solve the sub-problem of smaller size for each group in sequence, and this is iterated until convergence. Each sub-problem is solved based on the response surface method (RSM) due to its efficiency for small sized problem.

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Electrospinning으로 제조된 PMMA/PVA Multilayer bone plate의 생체적합성에 관한 연구

  • Gwak, Gyeong-A;Thai, Van Viet;Lee, Byeong-Taek;Song, Ho-Yeon
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2009.11a
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    • pp.43.1-43.1
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    • 2009
  • Bone plate는 골절된 뼈의 골 유합을 지지하기 위해서 정형외과, 신경외과, 성형외과 및 치과 등에서 널리 사용되고 있다. 하지만 기존의 bone plate는 대부분 금속으로 제작되어 있어 장기간 이식에 따른 부식 및 천연골 강도저하 등으로 인해 1~2년 후 재수술을 해야 하는 문제점을 갖고 있다. 본 연구에서는이런 금속 bone plate의 단점을 개선하고자 생체적합성이 우수한 생분해성 고분자 bone plate를 제작하였다. 사용된 고분자는 생체적합성과 생분해성이우수한 PVA(polyvinly alcohol)와 강도를 유지하기 위한 PMMA(poly methyl methacrylate)를 사용였다. Electrospinning 법으로 PVA와 PMMA fibrous mat를 제작하여 각 mat를 적층시킨 후 열압착을 하여 강도를 증가시킨 PMMA/PVA Mutlilayer bone plate을 제작하였다. 제작된 PMMA/PVA Mutlilayer bone plate의 생체적합성 평가를 위해 MTT assay, 생분해 특성을 관찰하기 위해 Micro-CT와 SBF(simulated body fluid) 내에서의 용해도를 관찰하였다. 또한조골세포의 부착과 분화에 미치는 영향을 SEM(scanning electron microscope)을통해 관찰하였고, 조골세포의 유전자 발현에 미치는 영향을 RT-PCR을통해 확인하였다.

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