• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.27 no.1
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• pp.179-188
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• 1997

This study was intended to compare the diagnostic ability between Waters' radiograph and CT in the diagnosis of midfacial fracture. The study group included 44 patients(male:32, female :12, age range :16-74 years old) with facial injury who underwent surgery. Waters' radiograph and both axial and coronal scanning were performed before surgery. Three oral radiologists and three non-oral radiologist interpreted 44 Waters' radiographs and 88 CT in three ways; 1) interpretation using Waters' radiograph only, 2) interpretation using CT only, 3) interpretation using Waters' radiograph and CT. The interpretation sites were confined to the walls of maxillary sinus; anterior, posterior, medial, lateral and superior wall. ROC curves were made with the findings during surgery as a gold standard except the posterior wall, where the joint evaluation of Waters' radiograph and CT by other three oral radiologists was used. ROC areas were compared according to the interpreting methods, the interpretation sites, and groups (R group ; oral radiologist group, N group ; non-oral radiologist group). The obtained results were as followed : 1. The diagnostic ability of CT only and Waters' radiograph and CT was higher than Waters' radiograph only in both groups(P<0.05). But there was no difference between CT only and Waters' radiograph and CT. 2. Generally, the diagnostic ability for the lateral antral wall was the highest and that for the posterior antral wall was the lowest in both groups(P<0.05). 3. In R group, for the anterior antral wall the diagnostic ability using CT only was increased but for the medial, lateral and superior antral walls the diagnostic ability was increased in only using Waters' radiograph and CT. 4. In N group, for the anterior and medial walls the diagnostic ability using CT only was increased. But for the posterior, lateral and superior antral walls there were no difference among three interpreting methods. 5. The diagnostic ability of R group was higher than N group in all interpreting methods.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.39 no.2
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• pp.71-76
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• 2013

Objectives: In three-dimensional computed tomography (3D-CT), the cant is evaluated by measuring the distance between the reference plane (or line) and the tooth. The purpose of this study was to determine the horizontal skeletal reference plane that showed the greatest correlation with clinical evaluation. Materials and Methods: The subjects were 15 patients who closed their eyes during the CT image taking process. The menton points of all patients deviated by more than 3 mm. In the first evaluation, clinical cant was measured. The distance from the inner canthus to the ipsilateral canine tip and the distance from the eyelid to the ipsilateral first molar were obtained. The distance between the left and right sides was also measured. In the second evaluation, skeletal cant was measured. Six reference planes and one line were used for the evaluation of occlusal cant: 1) FH plane R: Or.R - Or.L - Po.R; 2) FH plane L: Or.R - Or.L - Po.L; 3) F. Ovale plane R: Rt.F.Ovale - Lt.F.Ovale - Or.R; 4) F. Ovale plane L: Rt.F.Ovale - Lt.F.Ovale - Or.L; 5) FZS plane R: Rt.FZS - Lt.FZS - Po.R; 6) FZS plane R: Rt.FZS - Lt.FZS - Po.L, and; 7) FZS line: Rt.FZS - Lt.FZS. Results: The clinical and skeletal cants were compared using linear regression analysis. The FH plane R, FH plane L, and FZS line showed the highest correlation (P<0.05). Conclusion: The FH plane R and FH plane L are the most appropriate horizontal reference plane in evaluation of occlusal cant on 3D-CT.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.41 no.6
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• pp.155-164
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• 2004

Recently, we have remarkable developments in intelligent robot systems. The remarkable features of intelligent robot are that it can track user and is able to doface recognition, which is vital for many surveillance-based systems. The advantage of face recognition compared with other biometrics recognition is that coerciveness and contact that usually exist when we acquire characteristics do not exist in face recognition. However, the accuracy of face recognition is lower than other biometric recognition due to the decreasing in dimension from image acquisition step and various changes associated with face pose and background. There are many factors that deteriorate performance of face recognition such as thedistance from camera to the face, changes in lighting, pose change, and change of facial expression. In this paper, we implement a new sliding active camera system to prevent various pose variation that influence face recognition performance andacquired frontal face images using PCA and HMM method to improve the face recognition. This proposed face recognition algorithm can be used for intelligent surveillance system and mobile robot system.

• The korean journal of orthodontics
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• v.41 no.4
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• pp.224-236
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• 2011

Objective: The purpose of this study was to analyze the dental and basal arch forms in patients with normal occlusion using the computed tomography (CT) imaging method. Methods: CT images were taken from 27 normal occlusion subjects (male, 15; female, 12) and these images were reconstructed into three-dimensional models. A 3D-coordinate system was formed by setting the middle of the facial axis (FA) point of the maxillary central incisors as the origin. The morphology of the maxilla and mandibular dental and basal arches were analyzed by sectioning parallel to the maxillary occlusal plane. Results: There was no significant difference between A point and B point and between the maxillary 1st molars in both sides of the maxillary and mandibular basal bone. The dental arch was located more labially than the basal arch in the anterior portion. The bucco-lingual crossover of the dental arch and basal arch was formed at the molar region in the maxilla, and at the premolar region in the mandible. Conclusions: This study will help provide three-dimensional diagnostic information about the relationship between basal and dental arches in patients who have severe dental compensation and inappropriate jaw relationships.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.39 no.5
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• pp.217-223
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• 2013

Objectives: Buccal fracture of the mandibular proximal bone segment during bilateral sagittal split ramus osteotomy (SSRO) reduces the postoperative stability. The primary aim of this study is to evaluate the effect of this type of fracture on bone healing and postoperative stability after mandibular setback surgery. Materials and Methods: Ten patients who experienced buccal fracture during SSRO for mandibular setback movement were evaluated. We measured the amount of bone generation on a computed tomography scan, using an image analysis program, and compared the buccal fracture side to the opposite side in each patient. To investigate the effect on postoperative stability, we measured the postoperative relapse in lateral cephalograms, immediately following and six months after the surgery. The control group consisted of ten randomly-selected patients having a similar amount of set-back without buccal fracture. Results: Less bone generation was observed on the buccal fracture side compared with the opposite side (P<0.05). However, there was no significant difference in anterior-posterior postoperative relapse between the group with buccal fracture and the control group. The increased mandibular plane angle and anterior facial height after the surgery in the group with buccal fracture manifested as a postoperative clockwise rotation of the mandible. Conclusion: Bone generation was delayed compared to the opposite side. However, postoperative stability in the anterior-posterior direction could be maintained with rigid fixation.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.2
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• pp.166-172
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• 2018

In case of the treatment of maxillary anterior teeth, it should be taken into account the proper morphology, arrangement and color satisfying patient's esthetic demands. For this purpose, facial composition, dentofacial composition, dental composition and dentogingival composition should be considered making diagnosis and treatment plan in an esthetic point of view. In adjustable temporary crown state, careful evaluation and correction of the esthetic and functional aspect were performed, and the definite restoration was reproduced using double scan.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.10
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• pp.4903-4929
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• 2018

In this study, a fully automatic pose and expression invariant 3D face alignment algorithm is proposed to handle frontal and profile face images which is based on a two pass course to fine alignment strategy. The first pass of the algorithm coarsely aligns the face images to an intrinsic coordinate system (ICS) through a single 3D rotation and the second pass aligns them at fine level using a minimum nose tip-scanner distance (MNSD) approach. For facial recognition, multi-view faces are synthesized to exploit real 3D information and test the efficacy of the proposed system. Due to optimal separating hyper plane (OSH), Support Vector Machine (SVM) is employed in multi-view face verification (FV) task. In addition, a multi stage unified classifier based face identification (FI) algorithm is employed which combines results from seven base classifiers, two parallel face recognition algorithms and an exponential rank combiner, all in a hierarchical manner. The performance figures of the proposed methodology are corroborated by extensive experiments performed on four benchmark datasets: GavabDB, Bosphorus, UMB-DB and FRGC v2.0. Results show mark improvement in alignment accuracy and recognition rates. Moreover, a computational complexity analysis has been carried out for the proposed algorithm which reveals its superiority in terms of computational efficiency as well.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6419-6425
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• 2013

Background: Neoadjuvant chemotherapy (NACT) is a treatment modality whereby chemotherapy is used as the initial treatment of HNSCC in patients presenting with advanced cancer that cannot be treated by other means. It leads to shrinkage of tumours to an operable size without significant compromise to essential oro-facial organs of the patients. The molecular mechanisms behind shrinkage due to NACT is not well elucidated. Materials and Methods: Eleven pairs of primary HNSCCs and adjacent normal epithelium, before and after chemotherapy were screened for cell proliferation and apoptosis. This was followed by immunohistochemical analysis of some cell cycle (LIMD1, RBSP3, CDC25A, CCND1, cMYC, RB, pRB), DNA repair (MLH1, p53) and apoptosis (BAX, BCL2) associated proteins in the same set of samples. Results: Significant decrease in proliferation index and increase in apoptotic index was observed in post-therapy tumors compared to pre-therapy. Increase in the RB/pRB ratio, along with higher expression of RBSP3 and LIMD1 and lower expression of cMYC were observed in post-therapy tumours, while CCND1 and CDC25A remained unchanged. While MLH1 remained unchanged, p53 showed higher expression in post-therapy tumors, indicating inhibition of cell proliferation and induction of apoptosis. Increase in the BAX/BCL2 ratio was observed in post-therapy tumours, indicating up-regulation of apoptosis in response to therapy. Conclusions: Thus, modulation of the G1/S cell cycle regulatory proteins and apoptosis associated proteins might play an important role in tumour shrinkage due to NACT.

• Archives of Plastic Surgery
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• v.44 no.5
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• pp.370-377
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• 2017

Background Composite grafts are frequently used for facial reconstruction. However, the unpredictability of the results and difficulties with large defects are disadvantages. Adipose-derived stem cells (ADSCs) express several cytokines, and increase the survival of random flaps and fat grafts owing to their angiogenic potential. Methods This study investigated composite graft survival after ADSC injection. Circular chondrocutaneous composite tissues, 2 cm in diameter, from 15 New Zealand white rabbits were used. Thirty ears were randomly divided into 3 groups. In the experimental groups (1 and 2), ADSCs were subcutaneously injected 7 days and immediately before the operation, respectively. Similarly, phosphate-buffered saline was injected in the control group just before surgery in the same manner as in group 2. In all groups, chondrocutaneous composite tissue was elevated, rotated 90 degrees, and repaired in its original position. Skin flow was assessed using laser Doppler 1, 3, 6, 9, and 12 days after surgery. At 1 and 12 days after surgery, the viable area was assessed using digital photography; the rabbits were euthanized, and immunohistochemical staining for CD31 was performed to assess neovascularization. Results The survival of composite grafts increased significantly with the injection of ADSCs (P<0.05). ADSC injection significantly improved neovascularization based on anti-CD31 immunohistochemical analysis and vascular endothelial growth factor expression (P<0.05) in both group 1 and group 2 compared to the control group. No statistically significant differences in graft survival, anti-CD31 neovascularization, or microcirculation were found between groups 1 and 2. Conclusions Treatment with ADSCs improved the composite graft survival, as confirmed by the survival area and histological evaluation. The differences according to the injection timing were not significant.

• Journal of Trauma and Injury
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• v.30 no.4
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• pp.186-191
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• 2017

Purpose: Recently, as the number of people who enjoy water sports life in river or lake easy to accessible are increasing, that of the patients who are injured in water sports also does gradually. We intend to investigate the type of the injured patients of water sports and the riskiness of the sports in this study. Methods: We retrospectively looked into the medical records of the patients who were injured in water sports and visited a general hospital in Gangwondo-province from 2010 to 2015. Results: Total 146 patients came to the hospital during six years. Patients mostly occurred at younger ages, in summer, and on holidays, rather than weekdays. The most common lesions of injuries were faces (53 patients). The most common types of injuries were contusions (62 patients), followed by fractures (32 patients) and lacerations (26 patients). The most frequent fracture sites were the upper extremities (11 patients). Most of the trauma patients were mild, but a small number of patients with aspiration pneumonia occurred and their severity was higher than trauma patients. Conclusions: In this study, facial injuries were most frequent in water sports injuries. In the fractures, upper extremities were the most common fractured lesions. In addition, even if there is no direct trauma, aspiration pneumonia is serious, so caution should be taken with protective equipment suitable for water sports.