• Title/Summary/Keyword: self-occlusion

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A Vision-based Approach for Facial Expression Cloning by Facial Motion Tracking

  • Chun, Jun-Chul;Kwon, Oryun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.2 no.2
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    • pp.120-133
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    • 2008
  • This paper presents a novel approach for facial motion tracking and facial expression cloning to create a realistic facial animation of a 3D avatar. The exact head pose estimation and facial expression tracking are critical issues that must be solved when developing vision-based computer animation. In this paper, we deal with these two problems. The proposed approach consists of two phases: dynamic head pose estimation and facial expression cloning. The dynamic head pose estimation can robustly estimate a 3D head pose from input video images. Given an initial reference template of a face image and the corresponding 3D head pose, the full head motion is recovered by projecting a cylindrical head model onto the face image. It is possible to recover the head pose regardless of light variations and self-occlusion by updating the template dynamically. In the phase of synthesizing the facial expression, the variations of the major facial feature points of the face images are tracked by using optical flow and the variations are retargeted to the 3D face model. At the same time, we exploit the RBF (Radial Basis Function) to deform the local area of the face model around the major feature points. Consequently, facial expression synthesis is done by directly tracking the variations of the major feature points and indirectly estimating the variations of the regional feature points. From the experiments, we can prove that the proposed vision-based facial expression cloning method automatically estimates the 3D head pose and produces realistic 3D facial expressions in real time.

Clinical use of Platelet Rich Fibrin(PRF) in Various Hard and Soft Tissue Defect : Case Report (혈소판 유래 섬유소(Platelet Rich Fibrin(PRF))를 이용한 골결손부의 치료 : 증례보고)

  • Chee, Young-Deok;Go, Seo-Wook
    • Journal of Dental Rehabilitation and Applied Science
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    • v.23 no.4
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    • pp.303-312
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    • 2007
  • Recently several studies have been developed not only to apply bone materials to bony defect, but also to use osteogenic and osteoinductive materials to form bone more effectively. In 1998 Mark et al applied gel formation of PRP(platelet-rich plasma) in bony transplantation for mandibular reconstruction as one of the method of stimulating bone formation in maxillofacial area, which is contain of varies growth factors. After he reported that PRP accelerate bone formation, which is used in varies bone transplantation and augmentation with a good result. Especially there are amount of growth factors in PRP, and PRP increase angiogenesis, cell division, and mesenchymal cell growth. Moreover it is capable of osteoconduction, hemostatitis, anti-infection, forming the shape at transplantation, ease of handling, and recipient site stability. So it is known that success rate is high in bone transplantation. However PRP need tissue adhesive to make plasma to solid form. Thrombin and calcium chloride, component of PRP, is extracted from autogenic donor. So it is expensive to extract and there is possibility of hepatitis, AIDS, and hematogenous metastasis. After all, tissue adhesive have the limitation and danger of use. So we are willing to introduce that we had get some idea after using PRF(platelet-rich fibrin) in the various hard and soft tissue bony defect, which is self extracted simply and contain growth factors.

Effect of supportive periodontal treatment in the oral lichen planus patients (구강편평태선 환자에서 보조적 치주치료의 효과)

  • Kwon, Eun-Young;Choi, Jeomil;Lee, Ju-Youn
    • Journal of Dental Rehabilitation and Applied Science
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    • v.31 no.2
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    • pp.134-142
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    • 2015
  • Lichen planus is an immune-mediated mucocutaneous disease, affects more frequently middle-aged Caucasian women and makes signs and symptoms in the oral mucosa. Cutaneous lichen planus lesions cause itching but they are self-limiting, oral lichen planus lesions are usually chronic, recalcitrant to treatment and potentially premalignant in some cases. Although, oral lichen planus is non-plaque related disease, they possess particular problems because plaque control is complicated by pain and bleeding and might cause plaque-related disease. The resulting condition comprises accumulations of plaque, which again can influence the progress of oral lichen planus with burning sensation, spontaneous gingival bleeding. Thus, it should be noted that both medication and supportive periodontal treatment are essential for the remission of the lesions. This case report introduces topical corticosteroid therapy and supportive periodontal treatment including intensive oral hygiene procedures to obtain an improvement of subjective symptoms and objective changes and to prevent relapse the lesions.

Human Legs Motion Estimation by using a Single Camera and a Planar Mirror (단일 카메라와 평면거울을 이용한 하지 운동 자세 추정)

  • Lee, Seok-Jun;Lee, Sung-Soo;Kang, Sun-Ho;Jung, Soon-Ki
    • Journal of KIISE:Computing Practices and Letters
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    • v.16 no.11
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    • pp.1131-1135
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    • 2010
  • This paper presents a method to capture the posture of the human lower-limbs on the 3D space by using a single camera and a planar mirror. The system estimates the pose of the camera facing the mirror by using four coplanar IR markers attached on the planar mirror. After that, the training space is set up based on the relationship between the mirror and the camera. When a patient steps on the weight board, the system obtains relative position between patients' feet. The markers are attached on the sides of both legs, so that some markers are invisible from the camera due to the self-occlusion. The reflections of the markers on the mirror can partially resolve the above problem with a single camera system. The 3D positions of the markers are estimated by using the geometric information of the camera on the training space. Finally the system estimates and visualizes the posture and motion of the both legs based on the 3D marker positions.

Learning Similarity between Hand-posture and Structure for View-invariant Hand-posture Recognition (관측 시점에 강인한 손 모양 인식을 위한 손 모양과 손 구조 사이의 학습 기반 유사도 결정 방법)

  • Jang Hyo-Young;Jung Jin-Woo;Bien Zeung-Nam
    • Journal of the Korean Institute of Intelligent Systems
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    • v.16 no.3
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    • pp.271-274
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    • 2006
  • This paper deals with a similarity decision method between the shape of hand-postures and their structures to improve performance of the vision-based hand-posture recognition system. Hand-posture recognition by vision sensors has difficulties since the human hand is an object with high degrees of freedom, and hence grabbed images present complex self-occlusion effects and, even for one hand-posture, various appearances according to viewing directions. Therefore many approaches limit the relative angle between cameras and hands or use multiple cameras. The former approach, however, restricts user's operation area. The latter requires additional considerations on the way of merging the results from each camera image to get the final recognition result. To recognize hand-postures, we use both of appearance and structural features and decide the similarity between the two types of features by learning.

Shear Bond Strength of Resin Cements on the IPS e.max Press (IPS e.max Press에 대한 수종 레진 시멘트의 전단결합강도에 관한 연구)

  • Lee, Kyung-Eun;Kim, Yu-Lee;Shin, Chang-Yong;Dong, Jin-Keun
    • Journal of Dental Rehabilitation and Applied Science
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    • v.26 no.3
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    • pp.311-322
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    • 2010
  • The purpose of this study was to evaluate the bond strengths between IPS e.max Press and four different types of resin cements that often used for esthetic restoration. Disc shaped IPS e.max Press blocks(N=40, diameter: 12mm, thickness: 3mm) were fabricated according to the manufacture's instruction and cleaned with ultrasonic cleaner. They were embedded into an autopolymerizing acrylic resin. Fourty cylinder shaped resin block(Filtek Z350, diameter: 4.5mm, thickness: 3mm) were fabricated using a plastic tube. Each specimens were randomly divided into 4 experimental group and bonded each other using 4 different resin cements(Variolink II(light-cure), Variolink II(dual-cure), Calibra, Super-Bond C&B) according to the manufactures' recommendations. All the specimens were stored in normal saline at $37^{\circ}C$ for 24 hours before test. Universal testing machine at a crosshead speed of 1mm/min was used to evaluate the shear bond strength. The data were statistically analyzed using one-way ANOVA(P<.01). Multiple comparison was done by the Tukey HSD test. The shear bond strength of Super-Bond C&B to e.max was significantly lower than those of Calibra, Variolink II(light-cure), Variolink II(dual-cure) (P<.01). The shear bond strength of Calibra, Variolink II(light-cure), Variolink II(dual-cure) to e.max were not significantly different. The shear bond strengths of light-cure/dual-cure cement were higher than that of self-cure cement.

Comparison of Push-out Bond Strengths According to Relining Procedure and Cement Type on Fiber Post (Fiber post의 Relining 방법과 시멘트 유형에 따른 Push-out Bond Strength의 비교)

  • Kang, Hyun-Young;Cho, So-Yeun;Yu, Mi-Kyung;Lee, Kwang-Won;Kim, Kyoung-A
    • Journal of Dental Rehabilitation and Applied Science
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    • v.27 no.3
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    • pp.253-265
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    • 2011
  • When restoring endodontically treated teeth is the mismatch between fiber post size and post space diameter, the resin cement layer is excessively thick in post space and voids are likely to form in it, thus predisposing to de-bonding. The method to overcome this problem is to reline the fiber post with composite resin. This individual anatomic post improves the adaptation of post to root walls and decreases the resin cement thickness. The purpose of this in vivo study was to evaluate the push-out bond strength of fiber post according to relining procedure and luting agents type used for simplicity of clinical procedure. Forty-two extracted teeth were divides into six groups.(n=7) A1: relined fiber post cemented with Luxacore/all-bons 2, A2: non-relined fiber post cemented with Luxacore/all-bond2, B1: relinind fiber post cemented with Calibra/XP-bond, B2: non-relined fiber post cemented with Calibra/XP-bond, C1: relined fiber post cemented with RelyX Unicem, C2: non-relined fiber post cemented with RelyX Unicem Push-out bond strength was affected by interaction between relining procedure and luting agent type. Relined fiber post presented higher push-out bond strength value than non-relined fiber post and statically significant differences(p<0.05) Cementation with RelyX Unicem showed significantly higher bond strength than other luting agents(p<0.05).

Three Dimensional Comparative Study On The Accuracy Of Impression Technique Using New Impression Coping (새로운 인상용 코핑을 이용한 임플란트 인상법의 정확성에 대한 3차원적 비교 연구)

  • Kim, Se-Ra;Kim, In-Soo;Park, Sung-Jae;Lee, Byung-Ok;Ko, Sok-Min
    • Journal of Dental Rehabilitation and Applied Science
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    • v.26 no.3
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    • pp.323-337
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    • 2010
  • The objective of this study was to examine the availability of the new impression coping by comparing with conventional coping in implant pick-up impression technique. Five implant fixtures were installed on #14, 21, 23, 25, 27 in acrylic resin model. That model with 5 fixtures was standard model, which was divided 3 groups; using new flag type impression coping, conventional impression coping splinted with self-curing resin, conventional impression coping without splinting. We made metal circular cones for calculation 3-dimensional coordinates by attaching to implant fixtures or analogs. Three-dimensional relationships of each model were calculated. Data was analyzed by multiple ANOVA and Bonferroni. The accuracy of impression between using new flag type impression coping and conventional impression coping did not show differences in 3 - dimensional analysis.Within limitations of this study, the new flag type impression coping is available in implant pick-up impression technique.

Types of malocclusion and oral health effect index(OHIP-14) according to recognition of orthodontic treatment (부정교합 종류에 따른 교정치료의 인식과 구강건강영향지수(OHIP-14))

  • Yoon, Hyun-Seo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.12
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    • pp.434-442
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    • 2017
  • The purpose of this study was to examine the influence of type of malocclusion and orthodontic treatment awareness on quality of life among orthodontic patients in the region of Busan as well as to develop an educational program tailored to the type of malocclusion as a way to improve quality of life. A survey was conducted for approximately 6 months from December, 2015, and the answer sheets from 472 respondents were analyzed. The most common painful area was the teeth, and this case was most predominant in the respondents with level 2 malocclusion, who differed from others in that regard (p<0.001). Regarding the relationship between satisfaction with orthodontic treatment and quality of life, respondents who were more satisfied currently and who were neither quite confident nor quite unconfident were ahead of their counterparts in quality of life. Concerning the reason for receiving orthodontic treatment, quality of life was lower among patients who started to receive treatment due to pronunciation problems (p=0.013), chewing difficulty (p<0.001), and temporomandibular joint click sound (p<0.001). With regard to influential factors on oral health-related quality of life, time for starting to receive orthodontic treatment was most influential (p<0.001), followed by current satisfaction (p<0.001), changes in confidence (p=0.003), self-rated teeth status (p=0.008), and type of occlusion (p=0.019). Therefore, accurate analysis of the oral health status of orthodontic patients and customized oral health education are required to improve quality of life even during the period of orthodontic treatment.

Treatment of Subclavian Artery Injury in Multiple Trauma Patients by Using an Endovascular Approach: Two Cases (다발성 외상환자에서 혈관계 접근을 통해 치료한 쇄골하동맥 손상 2례)

  • Cho, Jayun;Jung, Heekyung;Kim, Hyung-Kee;Lim, Kyoung Hoon;Park, Jinyoung;Huh, Seung
    • Journal of Trauma and Injury
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    • v.26 no.3
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    • pp.243-247
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    • 2013
  • Introduction: Surgical treatment of subclavian artery (SA) injury is challenging because approaching the lesion directly and clamping the proximal artery is difficult. This can be overcome by using an endovascular technique. Case 1: A 37-year-old male was drawn into the concrete mixer truck. He had a right SA injury with multiple traumatic injuries: an open fracture of the right leg with posterior tibial artery (PTA) injury, a right hemothorax, and fractures of the clavicle, scapula, ribs, cervical spine and nasal bone. The injury severity score (ISS) was 27. Computed tomography (CT) showed a 30-mm-length thrombotic occlusion in the right SA, which was 15 mm distal to the vertebral artery (VA). A self-expandable stent($8mm{\times}40mm$ in size) was deployed through the right femoral artery while preserving VA flow, and the radial pulse was palpable after deployment. Other operations were performed sequentially. He had a viable right arm during a 13-month follow-up period. Case 2: A 25-year-old male was admitted to our hospital due to a motorcycle accident. The ISS was 34 because of a hemothorax and open fractures of the mandible and the left hand. Intraoperative angiography was done through a right femoral artery puncture. Contrast extravasation of the SA was detected just outside the left rib cage. After balloon catheter had been inflated just proximal to the bleeding site, direct surgical exploration was performed through infraclavicular skin incision. The transected SA was identified, and an interposition graft was performed using a saphenous vein graft. Other operations were performed sequentially. He had a viable left arm during a 15-month follow-up period. Conclusion: The challenge of repairing an SA injury can be overcome by using an endovascular approach.