Publications by authors named "Jang Yeol Lee"

Background: The standard procedure for managing skeletal class III malocclusion is maxillary advancement with mandibular setback. Occlusal plane-altering orthognathic surgery, such as jaw rotation, is useful as well. Although clockwise jaw rotation is a common procedure, its mechanism has not been well investigated.

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The aim of this study was to determine whether significant differences in postoperative stability exist between the lesser and the greater maxillary segments after cleft orthognathic surgery in patients with and without residual alveolar cleft. A retrospective study of orthognathic patients with unilateral cleft was conducted. The patients were divided into two groups according to maxillary status before surgery, with group 1 comprising single-piece maxilla and group 2 comprising two-piece maxilla.

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Background: The surgery-first orthognathic approach has been applied at our institution since 2007. However, its indications remain debated. The aim of this study was to investigate the reliability of the surgery-first approach to correct facial asymmetry compared to the traditional orthodontics-first approach using a novel artificial intelligence-based cephalometric analysis.

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We aimed to compare the reliability of the surgery-first approach and the traditional orthodontic-first approach for the correction of facial asymmetry based on the new classification of facial asymmetry. Patients with facial asymmetry who underwent orthognathic surgery between January 2016 and January 2019 were included. Cephalometric changes and relapse ratios were analyzed 12 months before and after surgery.

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Traditional orthognathic surgery has long been performed after presurgical orthodontic treatment. Despite some concerns, the surgery-first orthognathic approach (SFOA) or surgery-first approach (SFA) without presurgical orthodontic treatment has gradually gained popularity. In recent years, several articles dealing with the concepts of the SFA have been published worldwide.

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Traditionally, maxillomandibular advancement is an orthognathic surgical procedure that has been used to manage obstructive sleep apnea in patients not able or willing to maintain adherence to continuous positive airway pressure therapy or for patient who are not able to adhere to treatment. However, maxillomandibular advancement often leads to unsatisfactory cosmetic results.This prospective study investigated functional and esthetic outcomes using polysomnography and 3-dimensional computed tomography, after counterclockwise rotational orthognathic surgery.

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Sturge-Weber syndrome (SWS) is a rare neurocutaneous syndrome characterized by facial port-wine stains. Most patients with facial asymmetry due to SWS have soft and/or hard tissue hypertrophy and require both soft tissue correction and bone surgery. In our experience, because SWS patients are more likely than non-SWS patients to be dissatisfied after bone surgery because of limited soft tissue change, we compared soft tissue changes after bimaxillary surgery between facial asymmetry patients with and without SWS.

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The surgery-first approach (SFA) is a new paradigm in orthognathic surgery. In our experience over the last 10 years, SFA, particularly for the correction of the class III dentofacial deformity and facial asymmetry, has demonstrated high success rates without any major complications. However, many craniofacial surgeons remain concerned about the skeletal stability of SFA.

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Presurgical orthodontic treatment has long been known as a prerequisite in the traditional orthognathic approach. However, achieving ideal decompensation is very difficult even in the presurgical orthodontic period. For minimization of this problem, the surgery-first orthognathic concept has been introduced.

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Although pre-surgical orthodontic treatment has been accepted as a necessary process for stable orthognathic correction in the traditional orthognathic approach, recent advances in the application of miniscrews and in the pre-surgical simulation of orthodontic management using dental models have shown that it is possible to perform a surgery-first orthognathic approach without pre-surgical orthodontic treatment. This prospective study investigated the surgical outcomes of patients with diagnosed skeletal class III dentofacial deformities who underwent orthognathic surgery between December 2007 and December 2014. Cephalometric landmark data for patients undergoing the surgery-first approach were analyzed in terms of postoperative changes in vertical and horizontal skeletal pattern, dental pattern, and soft tissue profile.

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The aim of this retrospective cohort study was to evaluate the postoperative stability of sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy (IVRO) in pre-orthodontic orthognathic surgery (POGS) for skeletal Class III malocclusion. Thirty-seven patients (SSRO, n = 18; IVRO, n = 19) who underwent bimaxillary surgery were divided into two groups according to the type of surgery. During the postoperative period, there were no significant differences in anterior and superior movements of the mandible at point B between the two groups, but occlusal plane angle of the SSRO group significantly decreased more than that of the IVRO group (P = 0.

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Lingual orthodontics is increasing in popularity, with more adults receiving orthodontic treatment and opting for truly invisible appliances that do not have any limitations on the type of tooth movement they can achieve. In addition, there are a growing number of children receiving lingual appliances as they have been shown to significantly reduce the incidence of decalcification. Combining this growth in popularity with advances in computer technology, it is possible to treatment plan, design the appliance and have it custom made all with the click of a button.

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Although two dimensional cephalometry is the standard method for analyzing the results of orthognathic surgery, it has potential limits in frontal soft tissue analysis. We have utilized a 3 dimensional camera to examine changes in soft tissue landmarks in patients with skeletal class III dentofacial deformity who underwent two-jaw rotational setback surgery. We assessed 25 consecutive Asian patients (mean age, 22 years; range, 17-32 years) with skeletal class III dentofacial deformities who underwent two-jaw rotational surgery without maxillary advancement.

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Background: Orthognathic surgery with presurgical and postsurgical orthodontic treatment is the most widely accepted method for the correction of skeletal or dentoalveolar malocclusion. However, recent advancements in presurgical orthodontic simulations and postsurgical orthodontic treatments using miniscrews have shown remarkable stability and control of the occlusion after orthognathic surgery. Thus, we have adopted a surgery-first orthognathic approach without presurgical orthodontic treatment, based on a novel presurgical simulation process using a dental model.

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In this study, we propose a new method for the enhancement of intraarterial thrombolysis by use of an endovascular vibrating polymer actuator probe (VPAP), which is fabricated from an ionic polymer metal composite (IPMC) actuator. The endovascular VPAP was fabricated by combining 0.8 × 0.

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In this study, we propose a new method for enhancement of intraarterial thrombolysis using an ionic polymer-metal composite (IPMC) actuator. The purpose of this study was to test the mechanical thrombolysis efficiency of IPMC actuators and evaluate the endovascular vibrating polymer actuator probe for mechanical thrombolysis in a phantom model; 2 × 1 × 15 mm (2 mm in width, 1 mm in thickness, and 15 mm in length) and 0.8 × 0.

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On purpose to develop a polymer actuator with high stability in air-operation as well as large bending displacement, a series of ionic polymer-metal composites (IPMC) was constructed with poly(styrene sulfonate)-grafted fluoropolymers as ionomeric matrix and immidazolium-based ionic liquids (IL) as inner solvent. The prepared IPMC actuators exhibited greatly enhanced bending displacement compared to Nafion-based actuators. The actuators were stable in air-operation, maintaining initial displacement for up to 10(4) cycles or 24 h.

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Purpose: When grafts with solely osteoinductive or osteoconductive effects are used in the maxillary sinus, the medial wall of the sinus membrane should be reflected to receive the vascular supply and the osteoconductive effect. Because the internal sinus floor augmentation is a blind technique, it is impossible to directly verify whether the medial sinus wall is reflected in the operation. The purpose of this study is to describe the modality of choice among the grafting materials and techniques in relation to the width of the maxillary sinus through preoperative planning and measuring in computed tomography (CT) images.

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This study determined the accuracy of a camera system capable of recording three-dimensional facial images. A Rainbow 3D Camera Model 250 system (Genex Technologies Inc, Kensington, Md) was used to capture images of specific models: (1) a precalibrated precision model and (2) a mannequin model that served to simulate the human condition. To assess the accuracy of the camera system, repeated images of both models were recorded at two time points, one week apart.

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