• Title/Summary/Keyword: Contour Restoration

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Intracrevicular restoration and dentogingival junction(DGJ);Part: restorative contour and DGJ (치은열구내 수복과 Dentogingival junction(DGJ);제 2 부:수복물형태와 DGJ)

  • Lee, Young-Kyoo;Son, Seong-Heui
    • Journal of Periodontal and Implant Science
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    • v.29 no.1
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    • pp.117-130
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    • 1999
  • All contours of the restoration not directly related to occlusion are related to the gingival tissues only.And proper contour of restoration is essential for the health of the periodontal tissues.But there are so many controversies about the contour of the restoration, and there is no uniform agreement in the literature as to which contour of restoration is best for periodontium. In general, the contour of restoration means the supragingival contour only but in the case of the intracrevicular restorative procedure the subgingival contour of restoration must be considered. Because a portion of the restoration is placed in a gingival sulcus which is extremely vulnerable to periodontal disease. In this article the concepts or theories of the supragingival contour, the subgingival contour, and the emergence profile were discussed.The contour of the restoration and the biotype of the periodontium must be considered in intracrevicular restorative procedure.And sufficient tooth preparation is important factor to develop the proper contour of restoration which is kind to periodontium.

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Study on the Runoff Estimation Considering Stream Order (하천차수를 고려한 유출량 산정에 관한 연구)

  • Choi, Jong-In;Kang, Sang-Hyeok
    • Journal of the Korean Society of Hazard Mitigation
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    • v.5 no.4 s.19
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    • pp.17-27
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    • 2005
  • In this paper the watershed is divided by stream order law of Horton to estimate the runoff with stream order. We use the contour data to extract spatially distributed topographical information like stream channels and networks of sub-basins. A contour model is developed, validated, and adopted to estimate the effective stream order number for the runoff. The results show that the peak discharge which is divided into first river order was close to observed one. The contour model will provide effective informations to plan river works classified by sub-basins for river restoration.

Digital workflow of single visit full contour monolithic zirconia restoration with CEREC Omnicam intraoral scanner and fast zirconia sintering process (구강스캐너와 급속 지르코니아 소결을 이용한 당일 풀지르코니아 보철수복)

  • Lee, Soo Young
    • Journal of the Korean Academy of Esthetic Dentistry
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    • v.25 no.2
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    • pp.79-87
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    • 2016
  • Single visit monolithic restoration can be proceed with digital workflow which consist of intraoral scanning, dental CAD(computer aided design) and restoration milling with CAM(Computer aided manufacturing). While zirconia has more than 900MPa of flexural strength compared with 400MPa for lithium disilicate, shortened fabricating time of lithium disilicate is considered to be a better choice for fabricating single visit full contour monolithic restoration. However, new zirconia materials which are TZI C(Dentsply Sirona) and LUXEN Enamel(Dental Max), new induction heating method of sintering furnace, and new sintering protocols for MoSi2 heating elements sintering furnace offer significantly reduction of full contour monolithic zirconia restoration fabrication time with greater translucency. These new developments lead single visit zirconia restoration in reality.

A study on the design wax up technique for mandibular molar occlusion surface (하악구치 교합면의 design 조각법에 관한 연구)

  • Moon, Hee-Kyung
    • Journal of Technologic Dentistry
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    • v.24 no.1
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    • pp.107-126
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    • 2002
  • The first function of occlusion is mastication. Therefore the functional restoration of occlusal surface is very important. The restoration of occlusal surface is three method as wax bite technique, F.G.P. technique, cone technique. Many dental technician is using compound method. I am using compound method of wax bite technique and cone technique. I have knew common point on each teeth during I have waxing up wax pattern. So I studied on the design waxup technique for mandible molar occlusion. The results of the study were as follows; 1. The dam wax up method can restore axial contour of teeth very easy and make short working time of wax pattern. 2. The height of dam must be same with cusp of adjacent teeth. 3. Automatically the contour of tooth is appeared if the contour of dam is relationship with cuspid line of adjacent teeth. 4. The height of contour of buccal, lingual surface is formed natural curve to add fluid wax by gravitation. 5. The development groove of mandible first premolar is appeared V form. 6. The development groove of mandible second premolar is appeared Y form. 7, The development groove of mandible first molar is appeared M form. 8. The development groove of mandible second molar is W form. 9. The embrasure is formed to carve around contact point area as round convex. It affects to axial form of tooth. 10. The buccal, lingual groove of molar is formed parallel with direction of teeth arrangement.

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A Study on the design waxup technique for maxillary molar occlusion (상악구치 교합면의 design 조각법에 관한 연구)

  • Moon, Hee-Kyung
    • Journal of Technologic Dentistry
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    • v.21 no.1
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    • pp.97-114
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    • 1999
  • The first function of occlusion is mastication. Therefore the functional restoration of occlusal surface is very important. The restoration of occlusal surface is three method as wax bite technique, F.G.P. technique, cone technique. Many dental technician is using compound method. I have knew common point on each teeth during I have waxing up wax pattern. So I studied on the design waxup technique for maxillary molar occlusion. The results of the study were as follows ; 1. The dam wax up method can restore axial contour of teeth very easy and make short working time of wax pattern. 2. The height of dam must be same with cusp of adjacent teeth. 3. Automatically the contour of tooth is appeared if the contour of dam is relationship with cuspid line of adjacent teeth. 4. The height of contour of buccal, lingual surface is formed natural curve to add fluid wax by gravitation. 5. The development groove of Maxillary premolar is appeared V form. 6. The development groove of Maxillary molar is appeared W form. 7. The embrasure is formed to carve around contact point area as round convex. It affects to axial form of tooth. 8. I was knew that the lingual groove and stuart's groove of molar runs parallel with oblique ridge. 9. The buccal groove of molar is formed parallel with direction of teeth arrangement.

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Reconstruction of Mandible Defect after Tumor Ablation Surgery : Versatility of Fibular Free Flap Design (광범위 종양절제술 후 발생한 하악 결손의 재건 : 결손부위에 따른 비골 유리 피판의 다양한 디자인)

  • Seul Chul-Hwan;Lee Young-Dae;Tark Kwan-Chul;Lew Dae-Hyun
    • Korean Journal of Head & Neck Oncology
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    • v.21 no.2
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    • pp.190-195
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    • 2005
  • Background and Objectives: Fibula is the flap of choice for reconstruction of wide mandible defects after tumor ablation surgery. In mandible reconstruction, restoring the mandible frame to provide mandibular contour and dental arch while restoring masticatory function are important. Even though vascularized fibula can be osteotomized freely, proper design and flap insetting is not easy because of its three dimensional structure and difference in design according to the defect sites. We reviewed patients who underwent mandible reconstruction with fibular flaps according to the defect sites and suggest proper modification methods of fibular flap according to the various defects sites after tumor ablation surgery. Materials and Methods: Twelve consecutive mandible reconstruction with fibular free flaps were performed for defects after tumor ablation surgery. Patients were classified into 4 groups according to the type of mandibular defect(Group 1 : defect on central segment including symphysis, Group 2 : defect on lateral segment(with or without central segment) confined to body, Group 3 : defect on body and ascending ramus that does not include the condyle, Group 4 : defect including the condyle). Results: We suggest different modification methods of fibular free flap for each patient group. Group 1, 3 ; contour by using multiple closing wedge osteotomy. Group 2 ; single or double barrel reconstruction without wedge osteotomy. Group 4 ; contour using single or multiple wedge osteotomy and condylar reconstruction with costochondral graft. Conclusion: Fibular free flaps can be contoured to any desired shape after multiple osteotomies to restore various mandibular defects. It is a reliable and versatile method for reconstruction of mandibular defects after tumor ablation surgery.

Connected-component Labeling using Contour Following (윤곽추적 영역채색 기법)

  • 심재창;이준재;하영호
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.5
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    • pp.95-107
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    • 1994
  • A new efficient contour following algorithm for connected-component labeling processing is proposed. The basic idea of the algorithm is that the total number of downward chain codes is the same as one of upward chain codes along the closed contour. If the chain code direction is upward, then region start mark is assigned at the chain code departure pixel and if the chain code is downward, then region end mark is assigned at the chain code arrival pixel. The proposed algorithm extracts directly the contour information from only the current direction information of chain. This makes the algorithm simple and fast and requires less memory with comparison to the conventional algorithms.The proposed contour following algorithm can be applied to the various kind of image processing such as region filling, restoration and region feature extraction.

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Study of Hollow Letter CAPTCHAs Recognition Technology Based on Color Filling Algorithm

  • Huishuang Shao;Yurong Xia;Kai Meng;Changhao Piao
    • Journal of Information Processing Systems
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    • v.19 no.4
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    • pp.540-553
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    • 2023
  • The hollow letter CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) is an optimized version of solid CAPTCHA, specifically designed to weaken characteristic information and increase the difficulty of machine recognition. Although convolutional neural networks can solve CAPTCHA in a single step, a good attack result heavily relies on sufficient training data. To address this challenge, we propose a seed filling algorithm that converts hollow characters to solid ones after contour line restoration and applies three rounds of detection to remove noise background by eliminating noise blocks. Subsequently, we utilize a support vector machine to construct a feature vector for recognition. Security analysis and experiments show the effectiveness of this algorithm during the pre-processing stage, providing favorable conditions for subsequent recognition tasks and enhancing the accuracy of recognition for hollow CAPTCHA.

Pontic site development and soft tissue transfer of the esthetic area: a case report (심미적 부위에서 가공치 하방 잔존치조제의 형성 및 연조직 복제 모형을 이용한 고정성 보철물 수복증례)

  • Kim, Hak-Cheon;Noh, Kwantae;Kwon, Kung-Rock;Kim, Hyeong-Seob
    • The Journal of Korean Academy of Prosthodontics
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    • v.51 no.4
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    • pp.323-331
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    • 2013
  • Soft tissue collapse around prepared teeth and pontic is inevitable after removal of the provisional restoration during the impression taking procedures. When inserting gingival retraction cord, soft tissue is displaced to an undesired contour. Viscosity of impression material also causes gingival displacement. Therefore, the consideration to transfer the prosthetically contoured soft tissue to master cast is required, especially in the esthetic area. In this report, the methods to maintain the soft tissue contour and transfer to the mastercast will be introduced. Harmonious contour of the soft tissue can be achieved with provisional restoration and be transferred to the master cast with two different techniques mentioned in this case report.

Forehead reconstruction with a custom-made three-dimensional titanium implant in a Parry-Romberg syndrome patient

  • Kim, Jae Yoon;Jung, Bok Ki;Kim, Young Suk;Roh, Tai Suk;Yun, In Sik
    • Archives of Craniofacial Surgery
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    • v.19 no.2
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    • pp.135-138
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    • 2018
  • Parry-Romberg syndrome is a rare neurocutaneous syndrome characterized by progressive shrinkage and degeneration of the tissues usually on only one side of the face. It is usually difficult to restore the facial contour due to skin tightness. In this case report, we report a forehead reconstruction with custom-made three-dimensional (3D) titanium implant of a Parry-Romberg syndrome patient who was treated with multiple fat grafts but had limited effect. A 36-year-old man presented with hemifacial atrophy. The disease progressed from 5 to 16 years old. The patient had alopecia on frontal scalp and received a surgery using tissue expander. The alopecia lesion was covered by expanded scalp flap done 22 years ago. Also, he was treated with fat grafts on depressed forehead 17 years ago. However, it did not work sufficiently, and there was noted depressed forehead. We planned to make 3D titanium implant to cover the depressed area (from the superior orbital rim to the vertex). During the operation, we confirmed that the custom-made 3D implant accurately fit for the depressed area without any dead spaces. Previously depressed forehead and glabella were elevated, and the forehead contour was improved cosmetically. A custom-made 3D titanium implant is widely used for skull reconstruction and bring good results. In our case, the depressed forehead of a Parry-Romberg syndrome patient was improved by a 3D titanium implant.