• 제목/요약/키워드: Facial Landmarks

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10세에서 14세 사이 III급 부정교합자의 치아안면두개의 형태학적 특성에 대하여 (Dental and skeletal characteristics and growth in Class III malocclusion between skeletal ages of 10 and 14)

  • 민승기;이영준;박영국
    • 대한치과교정학회지
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    • 제33권6호
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    • pp.419-435
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    • 2003
  • 이 연구는 두부X선 규격사진을 이용하여 III급 부정교합자의 안모를 연령 성별로 분류하고,각 분류에 대한 두개 안면 형태의 특성을 구명하기 위하여 시행되었다. 정상교합자 60명과 III급 부정교합자 60명을 표본으로 하였으며 각 군은 10세, 12세, 14세 군 남녀로 구분되었다. 50개의 선 및 각계측치를 Krogman-Walker의 기준평면을 기준하여 측정하였다. 1. III급 부정교합군은 전방두개저의 길이와 안상각이 정상교합자군에 비하여 작고 하악골체와 하악수직고경이 큰 것으로 나타났으며, 이러한 차이는 남녀 모두 10세부터 유의하게 나타났다. III급 부정교합군에서의 하악하연각의 유의한 증가는 남녀 모두 12세때 나타났다. 2. III급 부정교합자군에서의 상악골의 후방 위치와 상악골체 크기의 유의한 감소는 남녀 모두 10세부터 나타난다. 3. III급 부정교합자군에서 유의한 하안면부 수직고경의 증가는 주로 하악골체 크기의 변화에 기인하는 것으로 관찰되었다. 하악골체의 경우 III급 부정교합자군에서 더 크고 전하방에 위치하는 것이 관찰되었다. III급 부정교합자군에서의 전체적인 수직고경의 유의한 증가는 12세군에서 유의하게 나타나기 시작한다. 4. 본 연구에서는 III급 부정교합자군에서의 두개저부각의 감소와 (Ba-S-N, 3A) 하악골체의 전방 위치는 남녀 모든 연령층에서 일관되게 관찰되었다. 이 결과는 Rothstein 등에 의해 주장된 II급 부정교합자군에서의 두개저부각의 변화가 하악골체의 전후방 위치에 영향을 주지 못한다는 주장을 부정하며, 디벳 등에 의해 주장된 앵글씨의 부정교합분류와 두개안면형태의 상관성에 대한 연구를 지지한다.

An Automatic Strabismus Screening Method with Corneal Light Reflex based on Image Processing

  • Huang, Xi-Lang;Kim, Chang Zoo;Choi, Seon Han
    • 한국멀티미디어학회논문지
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    • 제24권5호
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    • pp.642-650
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    • 2021
  • Strabismus is one of the most common disease that might be associated with vision impairment. Especially in infants and children, it is critical to detect strabismus at an early age because uncorrected strabismus may go on to develop amblyopia. To this end, ophthalmologists usually perform the Hirschberg test, which observes corneal light reflex (CLR) to determine the presence and type of strabismus. However, this test is usually done manually in a hospital, which might be difficult for patients who live in a remote area with poor medical access. To address this issue, we propose an automatic strabismus screening method that calculates the CLR ratio to determine the presence of strabismus based on image processing. In particular, the method first employs a pre-trained face detection model and a 68 facial landmarks detector to extract the eye region image. The data points located in the limbus are then collected, and the least square method is applied to obtain the center coordinates of the iris. Finally, the coordinate of the reflective light point center within the iris is extracted and used to calculate the CLR ratio with the coordinate of iris edges. Experimental results with several images demonstrate that the proposed method can be a promising solution to provide strabismus screening for patients who cannot visit hospitals.

Botulinum neurotoxin injection for treating plunged nose and post-rhinoplasty: anatomical perspectives of depressor septi nasi, nasalis, leveator labii superioris alaeque nasi muscle

  • Kyu-Ho Yi;Ji-Hyun Lee;Seon-Oh Kim;Hyewon Hu;Hyung-Jin Lee;You-Jin Choi;Tae-Hwan Ahn;Hee-Jin Kim
    • Anatomy and Cell Biology
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    • 제56권4호
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    • pp.409-414
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    • 2023
  • Botulinum neurotoxin (BoNT) injection for the treating plunged nose, post-rhinopasty and hyaluronic filler migration is common procedures in clinical settings. However, the lack of thorough anatomical understanding makes it difficult to locate the nose region muscles. The anatomical considerations concerned with BoNT injection into the nasalis, levator labii superioris alaeque, and depressor septi nasi muscles were reviewed in this study. The injection spots have been presented for the nasalis, levator labii superioris alaeque, and depressor septi nasi muscles, with the recommended injection technique for each muscle. We have suggested the ideal injection sites in association with outer anatomical landmarks of the nose region. Moreover, these proposals would support a more accurate procedure of BoNT injection in relieving plunged nose, preventing post-rhinoplasty deviation, and migration of the hyaluronic acid filler.

비제약적 환경에서 얼굴 주요위치 특징 서술자 기반의 얼굴인식 (Face Recognition Based on Facial Landmark Feature Descriptor in Unconstrained Environments)

  • 김대옥;홍종광;변혜란
    • 정보과학회 논문지
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    • 제41권9호
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    • pp.666-673
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    • 2014
  • 본 논문에서는 비제약적 얼굴 데이터 베이스를 위한 확장성 있는 얼굴 인식 방법을 연구하고, 간단한 실험 결과를 소개한다. 기존의 얼굴 인식 연구들은 주로 조명, 얼굴 각도, 표정, 배경 등 제약이 있는 환경에서의 정확도 향상에 초점을 맞추고 있어서 비제약적 얼굴 데이터 베이스에 사용하기에 적합하지 않다. 제안하는 얼굴인식 방법은 비제약적 얼굴 인식을 위한 특징 추출 알고리즘으로, 먼저 지역적 특징이 존재하는 눈, 코, 입과 같이 얼굴의 중요한 특징을 나타내는 영역을 분리한다. 각 얼굴 주요 위치는 고차원의 다중 스케일 국부 이진패턴 히스토그램(Multi-scale LBP histogram) 특징 벡터로 기술된다. 단일 얼굴 주요 위치에 해당하는 다중 스케일 국부 이진패턴 히스토그램 특징 벡터는 주성분 분석법(PCA: Principal Component Analysis)과 선형 판별 분석법(LDA: Linear Discriminant Analysis)의 차원 축소 과정을 통해 저차원 얼굴 특징 벡터를 생성한다. 저차원 얼굴 특징 벡터는 랭크 획득과 Precision at k(p@k) 성능 평가 방법을 이용하여 제안한 알고리즘의 얼굴 인식 성능을 검증한다. 본 연구는 FERET, LFW 및 PubFig83 데이터 베이스를 이용하여 얼굴 인식 실험을 수행하였으며, 제안한 알고리즘을 이용한 얼굴 인식 방법이 기존의 방법보다 향상된 인식성능을 보였다.

악교정 수술을 위한 한국 성인 정상교합자의 연조직 기준치 (CEPHALOMETRIC NORMS OF THE SOFT TISSUES OF KOREAN FOR ORTHOGNATHIC SURGERY)

  • 김경호;최광철;김진갑;박광호
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제27권3호
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    • pp.231-238
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    • 2001
  • This study was performed to evaluate soft tissue cephalometric norms for Korean adults which can be implemented in surgical orthodontic treatment planning using selected horizontal reference plane especially for Koreans (Male: $SN-7.5^{\circ}$, Female: $SN-9.0^{\circ}$) and a simplified analytical method. 70 males and 70 females consisting of freshmen of Yonsei University from 1996 to 1997 and students from the Dental College of Yonsei University were chosen according to clinical examination and cephalometric analysis. The samples had normal profiles, normal anteroposterior skeletal relationship(ANB angle of $0^{\circ}\;to\;4^{\circ}$ and Wits appraisal of -4.0mm to 0mm), and Class I molar and canine relationship. They had no missing or supernumerary teeth and had no experience of orthodontic or prosthetic treatment. After the selection of 15 soft tissue landmarks and the construction of horizontal and vertical reference lines, 25 measurements were taken. These consisted of vertical and horizontal linear measurements and angular measurements. The results were as follows. 1. Mean and standard deviation of the measurements were calculated in males and females. 2. Vertical measurements were comparably bigger in males than females whereas anterior facial height ratio(sN-Sn/Sn-sMe) and lower anterior facial height ratio(Sn-Stms/Stmi-sMe) showed no significant difference between sexes. 3. Most of the horizontal measurements in relation to the vertical reference line(G-perpendicular) showed no significant difference between sexes. 4. Nasofacial angle, columellar angle, nasolabial angle and facial contour angle showed no significant difference between sexes. 5. The upper and lower lip were positioned about $-1.0{\pm}2.0mm$ and $+1.0{\pm}2.0mm$ in relation to the Ricketts' esthetic line in both sexes. In this study, soft tissue cephalometric norms of Korean adults for orthognathic surgery were obtained.

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정모 및 측모 두부 방사선 규격사진을 이용한 3차원 계측 프로그램의 개발 -2. 악안면 구조에 대한 3차원적 시각화 및 측정프로그램 개발- (DEVELOPMENT OF THREE DIMENSIONAL MEASURING PROGRAM WITH FRONTAL AND LATERAL CEPHALOMETRIC RADIOGRAPHS -PART 2. 3-D VISUALIZATION AND MEASURMENT PROGRAM FOR MAXILLOFACIAL STRUCTURE-)

  • 이상한;삼열수;남극호;이근호;권대근
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제27권4호
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    • pp.321-329
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    • 2001
  • 안면 비대칭이나 반안면 왜소증등과 같은 악변형증 환자의 진단 및 치료계획을 수립함에 있어서 종합적이고도 3차원적인 접근을 하는 것이 중요하다. 최근 3차원 CT가 개발되었으나 이 경우 계측점의 정확성이 아직 확립되어 있지 않다. 최근들어 두부 위치를 보정하여 다른 시기에 촬영된 방사선 사진을 3차원적으로 비교할수 있도록 하는 방법이 소개되었다. 이러한 방법을 이용하여 얻어진 3차원 좌표값 자동적으로 계산한 후 3차원적 구조 분석 및 계측을 할 수 있는 컴퓨터 프로그램을 개발하였다. 이 프로그램은 정중면을 설정하는 개념에 입각하여 안면구조물의 변형정도를 다양한 방법으로 나타낼수 있으며 이러한 기능은 특히 안면 비대칭의 분석과 술전, 후 비대칭의 정도를 파악하는데 유용한 것으로 보인다.

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Early outcomes of cleft and palatal width following anterior palate repair (vomerine flap) in infants with wide cleft lip and palate

  • Saad, Arman Zaharil Mat;Chai, Koh Siang;Sulaiman, Wan Azman Wan;Johar, Siti Fatimah Noor Mat;Halim, Ahmad Sukari
    • Archives of Plastic Surgery
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    • 제46권6호
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    • pp.518-524
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    • 2019
  • Background Anterior palatal repair performed during cleft lip repair using a vomerine flap may assist in recruiting additional soft tissue for subsequent completion of palatoplasty, especially in patients with a wide cleft. We present our early results in the hope of triggering a re-evaluation of this technique regarding its advantages for maxillary growth through further studies of patients with a wide cleft. Methods A retrospective analysis of patients with complete unilateral and bilateral cleft lip and palate was performed, including cleft and palatal measurements taken during initial surgery (lip repair together with anterior palate repair) and upon completion of palatoplasty. Results In total, 14 patients were included in this study, of whom nine (63.3%) had unilateral cleft lip and palate and five (37.5%) had bilateral cleft. All patients had a wide cleft palate. Lip and anterior palate repair was done at a median age of 3 months, while completion of palatoplasty was done at a median age of 10.5 months. Measurements taken upon completion of palatoplasty showed significant cleft width reduction in the mid-palate and intertubercle regions; however, the palatal arch distances at nearby landmarks showed non-significant marginal changes. Conclusions Anterior palate repair using a vomerine flap significantly reduced the remaining cleft width, while the palatal width remained. Further research is warranted to explore the long-term effects of this technique in wide cleft patients in terms of facial growth.

Angle씨 제 3 급 부정교합 환자 치료 전후의 안모 연조직 변화에 관한 두부방사선 계측학적 연구 (A ROENTGENOCEPHALOMETRIC STUDY ON SOFT TISSUE PROFILE CHANGES IN PRE-POST TREATMENT OF ANGLE'S CLASS III MALOCCULUSION)

  • 김재우;손병화
    • 대한치과교정학회지
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    • 제13권2호
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    • pp.177-183
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    • 1983
  • The soft tissue covering of the face plays an important role in facial esthetics, speech and other physiologic functions. Thus, it is recognised by all clinical orthodontists that success of orthodontic treatment is closely related to the changes in soft tissues of the face. The purpose of this study was to evaluate the changes of bony and soft tissues in prepost treatment of Angle's Class III malocclusion. The sample consisted of 18 males and 37 females, pretreatment age of 9 years to 11 years. For this study 11 landmarks were plotted, 14 linear length, 4 soft tissue thickness and 2 angles were measured. The obtained results were as follows; 1. In the linear measurements of bony and soft tissue changes, A, Is, Ss, Ls and Li were located more anteriorly in both sexes. However Si and B showed more remarkable anterior movement in female. 2. In the comparison of the changes of the soft tissue thickness, Ss and Li in male subjects and Ss in female subjects increased. 3. In the degree of correlation between changes in the soft tissue profile and changes in the skeletal profile, Is: Ls, Il: Li and B: Si in both sexes had significant correlations. However A:Ss had remarkable significant correlation in female. 4. There were significant correlations between change in ${\angle}A$ and change in ${\angle}B$ in all sexes. 5. There were little correlation between changes in distance difference of Is and Ii and Change in distance difference of Ls and Li in all sexes.

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Evaluation of soft tissue asymmetry using cone-beam computed tomography after open reduction and internal fixation of zygomaticomaxillary complex fracture

  • Kim, Dong Hyuck;Kim, Rae Hyong;Lee, Jun;Chee, Young Deok;Kwon, Kyoung-Hwan
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제40권3호
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    • pp.103-110
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    • 2014
  • Objectives: In this study, we assessed soft tissue asymmetry that occurred after open reduction of unilateral zygomaticomaxillary complex (ZMC) fractures. We proposed a simple method to assess soft tissue asymmetry after reduction surgery by evaluating the symmetry between the affected and the unaffected sides. The factors affecting soft tissue contour after surgery were also analyzed. Materials and Methods: Subjects included patients admitted to Wonkwang University Dental Hospital from 2008 to 2013. Cone-beam computed tomography (CBCT) images of asymmetric patients who underwent open reduction at least 3 months prior were compared with healthy patients. Results: The degree of asymmetry was measured in both the open reduction and control groups. Landmarks that showed a statistically significant difference between the two groups were zygion ($1.73{\pm}0.24mm$), bucclae ($1.08{\pm}0.26mm$), point of cheek ($2.05{\pm}0.33mm$) and frontozygomatic point ($1.30{\pm}0.31mm$). Conclusion: When compared with the normal group, asymmetry can occur in the affected side, which usually shows depression of overlying soft tissue and is statistically significantly different. Evaluation of soft tissue asymmetry with CBCT images after open reduction of ZMC fracture is useful.

Three-dimensional assessment of upper lip positional changes according to simulated maxillary anterior tooth movements by white light scanning

  • Kim, Hwee-Ho;Lee, Jin-Woo;Cha, Kyung-Suk;Chung, Dong-Hwa;Lee, Sang-Min
    • 대한치과교정학회지
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    • 제44권6호
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    • pp.281-293
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    • 2014
  • Objective: Esthetic improvements during orthodontic treatment are achieved by changes in positions of the lips and surrounding soft tissues. Facial soft-tissue movement has already been two-dimensionally evaluated by cephalometry. In this study, we aimed to three-dimensionally assess positional changes of the adult upper lip according to simulated maxillary anterior tooth movements by white light scanning. Methods: We measured changes in three-dimensional coordinates of labial landmarks in relation to maxillary incisor movements of normal adults simulated with films of varying thickness by using a white light scanner. Results: With increasing protraction, the upper lip moved forward and significantly upward. Labial movement was limited by the surrounding soft tissues. The extent of movement above the vermilion border was slightly less than half that of the teeth, showing strong correlation. Most changes were concentrated in the depression above the upper vermilion border. Labial movement toward the nose was reduced significantly. Conclusions: After adequately controlling several variables and using white light scanning with high reproducibility and accuracy, the coefficient of determination showed moderate values (0.40-0.77) and significant changes could be determined. This method would be useful to predict soft-tissue positional changes according to tooth movements.