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1.
J Craniofac Surg ; 33(8): 2602-2605, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36409877

RESUMO

BACKGROUND: Upper blepharoplasty is 1 of the most popular cosmetic procedures in Asia. As people become older, they develop soft tissue atrophy and multiple folds due to a sunken upper eyelid. Furthermore, people with thin upper eyelid skin are more likely to develop multiple folds, even at a young age. The authors investigated the effectiveness of a transverse mattress suture technique to prevent recurrence during upper blepharoplasty in patients with primary multiple folds. PATIENTS/METHODS: Data on 656 patients with primary multiple folds who underwent upper blepharoplasty from March 2017 to January 2020 were retrospectively reviewed. The authors compared the operative time, patients' satisfaction, panel assessment, and complications according to whether the suture technique was used. RESULTS: Among 656 patients, 228 were lost to follow-up or had incomplete data; therefore, the files of 428 patients were analyzed. In total, 199 patients did not undergo the suture technique, whereas 229 patients did. Statistically significant differences were found between the 2 groups in patients' satisfaction, aesthetic results, and recurrence. However, between-group difference was not significant in terms of symmetry or complications such as hematoma and swelling. CONCLUSIONS: People with thin upper eyelid skin or slightly protruding eyes are more likely to develop multiple folds at a young age, even in their teens or 20s. The authors performed a skin suture during upper blepharoplasty, and then performed a transverse mattress suture on the spots where multiple folds are expected. Patients who underwent the suture technique showed better aesthetic results and a significantly lower recurrence rate.


Assuntos
Blefaroplastia , Estética Dentária , Adolescente , Humanos , Estudos Retrospectivos , Pálpebras/cirurgia , Técnicas de Sutura
2.
J Craniofac Surg ; 31(3): 813-815, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049913

RESUMO

BACKGROUND: Alveolar clefts give rise to many aesthetic and functional problems among affected patients. Therefore, surgical adjustments of the bony defective anomalies are important. The authors performed secondary bone grafts and analyzed the effects particularly on the nasal septum and maxillary area (midface). METHODS: The patients who had alveolar bone grafts were retrospectively reviewed with pre/postoperative 3-dimensional computed tomography; the measurements included distances between the anterior nasal spine (ANS) and the vertical midline, angles between the nasal septum and the transverse line, and angles between the floor of the pyriform aperture and the transverse line. RESULTS: A total number of 23 patients were finally included in the study. The mean age of the patients was 9.7 ±â€Š1.95 years (range, 7-14 years). The mean distance between the ANS and the vertical midline was 5.3 ±â€Š4.70 mm/4.9 ±â€Š4.15 mm pre/postoperatively, showing the mean paired difference of 0.4 ±â€Š0.89 mm (P < 0.05). The mean angles between the nasal septum and the transverse line and between the floor of the pyriform aperture and the transverse line were 64.5 ±â€Š14.69°/65.9 ±â€Š13.73° and 21.7 ±â€Š8.94°/11.5 ±â€Š7.03° pre/postoperatively, showing the mean paired differences of -1.4 ±â€Š2.78° and 10.1 ±â€Š8.20°, respectively (both P < 0.05). CONCLUSION: The results suggest that secondary alveolar bone grafting has expanded effects on the adjacent midfacial structures.


Assuntos
Fissura Palatina/diagnóstico por imagem , Maxila/diagnóstico por imagem , Septo Nasal/diagnóstico por imagem , Adolescente , Enxerto de Osso Alveolar , Transplante Ósseo , Criança , Fissura Palatina/cirurgia , Feminino , Humanos , Masculino , Maxila/cirurgia , Septo Nasal/cirurgia , Período Pós-Operatório , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
3.
J Craniofac Surg ; 29(5): 1241-1244, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29608475

RESUMO

Tear trough deformity has been an area that has received much attention in terms of esthetic improvements. Fat transposition has been commonly used for the treatment of tear trough deformity. As some patients have had minimal improvement by that method, we propose the use of fat grafting combined with open blepharoplasty to complement the sunken area, including some of anterior maxilla region, and evaluate and precisely remove the excessive tissue.Lower blepharoplasty was performed by separating the skin and muscle flap. The excessive or laxed tissue was evaluated during the procedure and resected in each flap. Fat grafting was performed after completing a lower blepharoplasty, to ensure accurate placement on the spot where the surgeon originally intended. Overcorrection is not recommended.No serious complications were reported during a period of 10 years. Only 4 patients required a secondary fat injection.Patients who require structural correction of the lower eyelid area (eg, aggressive herniated fat, excessive skin laxity, or bulky orbicularis oculi muscle) and who need complementary material to fill the lower lid area (eg, deep, wide sunken area or relative exophthalmos) are good candidates for blepharoplasty with a fat grafting procedure.


Assuntos
Tecido Adiposo/transplante , Blefaroplastia/métodos , Doenças Palpebrais/cirurgia , Pálpebras/cirurgia , Retalhos Cirúrgicos/cirurgia , Humanos , Complicações Pós-Operatórias
4.
J Craniofac Surg ; 28(7): 1661-1663, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28806380

RESUMO

INTRODUCTION: The philtral column has an important aesthetic significance and is especially important in patients with cleft lip. If the integrity of the philtrum cannot be preserved in patients of unilateral clefts, these patients will have profound abnormalities in their facial musculature. The purpose of this study was to analyze the effects of dermal grafting on the philtral column in patients with a unilateral alveolar cleft. METHODS: The authors retrospectively studied dermal grafts performed in Konkuk University Medical Center between January 2009 and January 2015. A total of 26 patients with unilateral cleft lip were included in this study; the authors measured philtral symmetry based on differences in convexity and angle using clinical photos. Additionally, panel evaluation was performed. RESULTS: Of 26 patients enrolled, 21 completed follow-up and had adequate photographs. Five patients who were lost to follow-up were excluded. The difference in convexity decreased from 0.25 to 0.15 (P < 0.005) and the difference in angle decreased from 10.76 to 6.43 (P < 0.005). The panel evaluation indicated that patient appearances were significantly improved (P < 0.001). DISCUSSION: In patients with secondary cleft lip deformity of the philtral depression, the authors' procedure may augment the thickness of the philtral ridge and have positive aesthetic outcomes.


Assuntos
Fenda Labial/cirurgia , Lábio/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Transplante de Pele/métodos , Humanos , Estudos Retrospectivos
5.
J Craniofac Surg ; 28(5): 1305-1307, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28582293

RESUMO

INTRODUCTION: Alveolar bone grafting not only stabilizes the alveolar arch, but also provides positive aesthetic outcomes. However, there have been no reports about the inclinations of the incisor and canine or the change in occlusion after alveolar bone grafting. Therefore, the purpose of this study is to analyze the effects of alveolar bone grafting on tooth angles and changes in occlusion in patients with a unilateral alveolar cleft, using three-dimensional computed tomography. METHODS: The authors retrospectively studied alveolar bone grafts performed in Konkuk University Medical Center between January 2008 and January 2013. A total of 40 patients with unilateral alveolar cleft were included in this study; the authors measured the changes in tooth angles and changes in anterior and molar occlusion before and after bone grafting. RESULTS: Of the 40 patients enrolled, 21 completed follow-up and had adequate computed tomography imaging studies. Ten patients who were lost during the follow-up period, and 9 with inadequate images, were excluded. The anterior occlusion increased from -2.21 to 0.19 mm (P < 0.0001) and the molar occlusion increased from 0.75 to 2.10 (P < 0.0001). The dental angle decreased from 25.23° to 15.32° (P = 0.001). DISCUSSION: Alveolar bone grafting provides support to the tooth root and changes the inclination of the tooth, resulting in changes in occlusion and positive aesthetic outcomes.


Assuntos
Enxerto de Osso Alveolar , Fissura Palatina/cirurgia , Má Oclusão/terapia , Criança , Feminino , Humanos , Masculino , Má Oclusão/diagnóstico por imagem , Estudos Retrospectivos
6.
J Craniofac Surg ; 28(8): 1972-1975, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28953160

RESUMO

The medial epicanthal fold is one of the racial anatomic characteristics of Asians. As medial epicanthoplasty has become one of the most common cosmetic surgeries among Asians, the need for revision of overcorrected medial epicanthus also increased. In revision medial epicanthoplasty, an autologous tissue graft to the subcutaneous plane is used to reduce postoperative scar. Medial epicanthoplasty, using V-Y advancement and rotation flap, was performed in 93 patients (revision medial epicanthoplasty with autologous tissue graft, 60 patients; revision medial epicanthoplasty only, 33 patients). A V-Y and rotation flap was designed to cover the overexposed lacrimal lake. A small amount of fat tissue and orbicularis oculi muscle were harvested from the upper eyelid through the double-fold line and grafted to the subcutaneous space of the medial epicanthal area. We evaluated the patients' satisfaction with the overall outcome and scar. The mean intercanthal distance increased from 32.3 mm before surgery to 34.6 mm after surgery. Satisfaction with the scar and overall outcome was higher in the patient group who underwent medial epicanthoplasty with autologous tissue graft. No complication was observed in the autologous tissue graft group, whereas 1 patient who underwent medial epicanthoplasty without autologous tissue graft showed recurrence of the medial epicanthal fold, 5 months after surgery. Medial epicanthoplasty with autologous tissue graft is a simple and reliable method to repair the overcorrected medial epicanthus that can efficiently increase the intercanthal distance and prevent scar contracture.


Assuntos
Tecido Adiposo/transplante , Blefaroplastia/métodos , Pálpebras/cirurgia , Músculos Faciais/transplante , Tela Subcutânea/transplante , Adolescente , Adulto , Povo Asiático , Blefaroplastia/efeitos adversos , Cicatriz/etiologia , Cicatriz/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Reoperação , Retalhos Cirúrgicos , Transplante Autólogo , Adulto Jovem
7.
J Craniofac Surg ; 27(5): 1143-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27380564

RESUMO

INTRODUCTION: Septorhinoplasty in cleft patients is relatively difficult to perform and the outcomes are often unsatisfactory owing to weakness of the cartilage. Therefore, providing support to the cartilage is necessary. The authors used bioabsorbable mesh as a spreader or batten graft to support the septum in cleft patients those with weak cartilages. The purpose of this study was to evaluate the efficacy of bioabsorbable mesh when performing septorhinoplasty in cleft patients. METHODS: Between 2009 and 2013, 34 patients with cleft lip and nose underwent open septorhinoplasty by using bioabsorbable mesh at the Konkuk University Medical Center. The authors determined the nasolabial angle, Goode ratio, alar base-nasal tip-columellar base angle, and columellar axis angle and performed a panel evaluation. RESULTS: In all, 29 of the 34 patients were included; 5 patients were excluded as lost to follow-up. The nasolabial angle increased from 85.69° to 91.62° (P = 0.0032), and the mean Goode ratio increased from 0.51 to 0.55, which was approximately the ideal value (P = 0.0017). The alar base-nasal tip-columellar base angle decreased from 36.28 to 31.74 (P < 0.0001). The columellar axis angle increased from 82.36 to 86.90 (P < 0.0001). DISCUSSION: As bioabsorbable mesh can provide strong support, results in good esthetic outcomes, and causes minimal complications, it can be used in septorhinoplasty for cleft patients.


Assuntos
Implantes Absorvíveis , Fenda Labial/cirurgia , Septo Nasal/cirurgia , Nariz/anormalidades , Rinoplastia/métodos , Telas Cirúrgicas , Adolescente , Adulto , Estética , Feminino , Humanos , Masculino , Cartilagens Nasais/cirurgia
8.
J Craniofac Surg ; 26(4): 1178-81, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26080153

RESUMO

INTRODUCTION: Maxillary distraction osteogenesis is a reliable treatment for cleft lip and palate with midfacial retrusion. The purpose of this study was to evaluate the results of long-term follow-up in patients with cleft lip and palate after maxillary distraction osteogenesis and to find clinical factors related to relapse. From February 2002 to June 2008, 21 patients with severe class III malocclusion were treated at our hospital. We performed distraction osteotomy with a rigid external distractor device. The distraction length was more than 15 mm in all patients. METHODS: Preoperative and postoperative lateral cephalometric radiographs were used for analysis. The sella-nasion-subnasale, sella-nasion-supramentale, and point-A-point-B-nasion (sella-nasion-subnasale-sella-nasion-supramentale) angles were recorded. The timelines for follow-up were preoperatively, after distraction, after consolidation, at 3 years, and once fully grown (5- to 8-year follow-ups). A comparative analysis of clinical factors was performed for the relapsing and nonrelapsing groups. RESULTS: Of the 21 patients, 14 had relapsed. The mean age in the relapsing group was 9.1 years (7 boys and 7 girls) with 9 patients with unilateral cleft palate and 5 c bilateral cleft palate. The mean age in the nonrelapsing group was 11.7 years (4 boys and 3 girls) with 5 patients with unilateral cleft palate and 2 patients with bilateral cleft palate. DISCUSSION: Despite greater anterior overcorrection, relapse occurred owing to scar tissue retraction and mandibular compensatory hypertrophy. The results suggest that the younger the patient, the more likely relapse will occur.


Assuntos
Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Maxila/cirurgia , Osteogênese por Distração/instrumentação , Osteotomia de Le Fort/métodos , Criança , Feminino , Seguimentos , Humanos , Masculino , Recidiva , Fatores de Tempo , Resultado do Tratamento
9.
Ann Plast Surg ; 73(1): 77-80, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23511740

RESUMO

BACKGROUNDS: The aims of the present study were to determine the exact level of separation of the upper lateral cartilage from the septal cartilage, and to classify the patterns of connection between the upper lateral cartilage and the lower lateral cartilage. METHODS: We dissected and photographed 60 sides of noses; 18 specimens were sectioned and stained with Masson's trichrome. RESULTS: The mean length of the connection between the upper lateral cartilage and septal cartilage was 16.1 mm. The mean level for separation of the upper lateral cartilage was 7.5 mm from the nasal bone. The pattern of connection between the upper lateral cartilage and lower lateral cartilage could be classified into five types: disconnection, end-to-end, overlap, scroll, and reverse scroll. CONCLUSIONS: The results of the present study will be helpful for surgical procedures such as nasal hump reduction and nasal cartilage work and also provide information for the anthropometric study of the nose.


Assuntos
Povo Asiático , Cartilagens Nasais/anatomia & histologia , Rinoplastia , Idoso , Idoso de 80 Anos ou mais , Antropometria/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia
10.
Foods ; 13(13)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38998472

RESUMO

Chili peppers (Capsicum annuum L.) are economically valuable crops belonging to the Solanaceae family and are popular worldwide because of their unique spiciness and flavor. In this study, differences in the metabolomes of landrace (Subicho) and disease-resistant pepper cultivars (Bulkala and Kaltanbaksa) widely grown in Korea are investigated using a 1H NMR-based metabolomics approach. Specific metabolites were abundant in the pericarp (GABA, fructose, and glutamine) and placenta (glucose, asparagine, arginine, and capsaicin), highlighting the distinct physiological and functional roles of these components. Both the pericarp and placenta of disease-resistant pepper cultivars contained higher levels of sucrose and hexoses and lower levels of alanine, proline, and threonine than the traditional landrace cultivar. These metabolic differences are linked to enhanced stress tolerance and the activation of defense pathways, imbuing these cultivars with improved resistance characteristics. The present study provides fundamental insights into the metabolic basis of disease resistance in chili peppers, emphasizing the importance of multi-resistant varieties to ensure sustainable agriculture and food security. These resistant varieties ensure a stable supply of high-quality peppers, contributing to safer and more sustainable food production systems.

11.
Arch Plast Surg ; 50(1): 101-105, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36755644

RESUMO

Benign cartilaginous tumors, known as chondrogenic tumors, show cartilage components in the microscopic diagnosis. We present two clinical cases with cartilaginous tumors of the toes showing distinctive clinical manifestations. Two juvenile patients visited our outpatient clinic due to tumors with toenail deformities. A 10-year-old girl presented with a palpable mass with a nail deformity on the left third toe. The initial pathology report was soft tissue chondroma until complete resection. Another 15-year-old male patient visited the dermatology department with a toenail deformity and underwent a punch biopsy. The pathology report was fibrosis with myxoid degeneration. Excisional biopsies were performed for both patients. In the operative field, we observed exophytic tumors connected to the distal phalangeal bones. The final pathology reports were subungual osteochondroma on both patients. The specimen exhibited mature bone trabeculae with a focal cartilaginous cap. Benign cartilaginous tumors have a slow, progressive course and do not show significant symptoms. However, tumors in subungual areas are accompanied by toenail deformities and they can cause pain. Their clinical characteristics lead to a delayed diagnosis. Surgeons can be confused between soft tissue and chondrogenic tumors. When they conduct physical examinations, these categories should be considered in the differential diagnosis.

12.
Sci Rep ; 13(1): 1932, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732582

RESUMO

The human facial skeleton consists of multiple segments and causes difficulty during analytic processes. We developed image analysis software to quantify the amount of injury and validate the smooth curvature of the surface after facial bone reduction surgery. Three-dimensional computed tomography images of facial bone were obtained from 40 patients who had undergone open reduction surgery to treat unilateral zygomaticomaxillary fractures. Analytic software was developed based on the discrete curvature of a triangular mesh model. The discrete curvature values were compared before and after surgery using two regions of interest. For the inferior orbital rim, the weighted average of curvature changed from 0.543 ± 0.034 to 0.458 ± 0.042. For the anterior maxilla, the weighted average of curvature changed from 0.596 ± 0.02 to 0.481 ± 0.031, showing a significant decrement (P < 0.05). The curvature was further compared with the unaffected side using the Bray-Curtis similarity index (BCSI). The BCSI of the inferior orbital rim changed from 0.802 ± 0.041 to 0.904 ± 0.015, and that for the anterior maxilla changed from 0.797 ± 0.029 to 0.84 ± 0.025, demonstrating increased similarity (P < 0.05). In computational biology, adequate analytic software is crucial. The newly developed software demonstrated significant differentiation between pre- and postoperative curvature values. Modification of formulas and software will lead to further advancements.


Assuntos
Fraturas Cranianas , Telas Cirúrgicas , Humanos , Maxila/cirurgia , Tomografia Computadorizada por Raios X/métodos
13.
Nanomaterials (Basel) ; 13(9)2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-37176984

RESUMO

Polypropylene (PP) is used as a housing material in automotive headlamps but can cause fogging as a result of absorbed moisture and temperature differences between the exterior and interior of the housing. In this study, PP was combined with a graphene/montmorillonite hybrid (MMT-G) to yield a nanocomposite with reduced moisture absorption. Crucially, the modified nanofiller had low hydrophilicity and good compatibility with the PP matrix. Notably, the water contact angle of the MMT-G improved by 676%. Furthermore, the maximum moisture absorption of the PP/MMT-G nanocomposites was reduced by up to 11.22% compared to that of commercial PP composites, and the weight of the headlamp housing was decreased by 3.6%. Therefore, the designed nanocomposites are expected to help mitigate headlamp fogging while slightly reducing the housing weight.

14.
Polymers (Basel) ; 14(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35567019

RESUMO

The electrical properties of carbon-based filler-embedded polymer nanocomposites are essential for various applications such as antistatic and electromagnetic interference (EMI) applications. In this study, the impact of additives (i.e., ethylene-co-acid-co-sodium acid copolymer-based ionomer and cyanuric acid) on the antistatic, mechanical, thermal, and rheological properties of extruded multiwalled carbon nanotube (MWCNT)/polyoxymethylene (POM) nanocomposites were systematically investigated. The effects of each additive and the combination of additives were examined. Despite a slight reduction in mechanical properties, the incorporation of ionomer (coating on CNTs) and/or cyanuric acid (π-π interaction between CNTs and cyanuric acid) into the POM/CNT nanocomposites improved the CNT dispersity in the POM matrix, thereby enhancing electrical properties such as the electrical conductivity (and surface resistance) and electrical conductivity monodispersity. The optimum composition for the highest electrical properties was determined to be POM/1.5 wt% CNT/3.0 wt% ionomer/0.5 wt% cyanuric acid. The nanocomposites with tunable electrical properties are sought after, especially for antistatic and EMI applications such as electronic device-fixing jigs.

15.
Carbohydr Polym ; 290: 119485, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35550772

RESUMO

Here, we composite an artificial leaf comprising a transparent hydrogel sheet, vein structures, and a photosynthetic system using cellulose nanofibers (CNFs) which can be produced from a biomass. A simple imprinting using a 3D printed stamp enabled the formation of fluidic channels in the hydrogel, embedding living cells without toxic chemistry or a drying process. Microalgae in the hydrogel grows and proliferates under ambient condition for a long period because of the continuous supply of nutrient from the channels, which is more effective for metabolic bioactivity than a flat sheet cultured in a bulk solution. This mimicry of the plant leaf provides a potential for a whole artificial plant. In addition, the simple fabrication of fluidic channels in the hydrogel can be applied to diverse living organisms, including bacteria, animal, and plant cells.


Assuntos
Nanofibras , Animais , Celulose/química , Hidrogéis/química , Nanofibras/química , Folhas de Planta
16.
Arch Craniofac Surg ; 23(3): 134-138, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35811346

RESUMO

The scalp is the thickest skin in the body and protects the intracranial structures. The coverage of a large scalp defect is a difficult surgical procedure, the full details of which must be considered prior to the procedure, such as defect size and depth, and various factors related to the patient's general condition. Although a free flap is the recommended surgical procedure to cover large scalp defects, it is a high-risk operation that is not appropriate for all patients. As such, other surgical options must be explored. We present the case of a patient with an ulcer on the scalp after wide excision and split-thickness skin graft for squamous cell cancer. We successfully performed a reverse temporalis muscle flap for this patient.

17.
J Pers Med ; 12(8)2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-36013242

RESUMO

Severe burns may lead to a series of pathophysiological processes that result in death. Machine learning models that demonstrate prognostic performance can be used to build analytical models to predict postoperative mortality. This study aimed to identify machine learning models with the best diagnostic performance for predicting mortality in critically ill burn patients after burn surgery, and then compare them. Clinically important features for predicting mortality in patients after burn surgery were selected using a random forest (RF) regressor. The area under the receiver operating characteristic curve (AUC) and classifier accuracy were evaluated to compare the predictive accuracy of different machine learning algorithms, including RF, adaptive boosting, decision tree, linear support vector machine, and logistic regression. A total of 731 patients met the inclusion and exclusion criteria. The 90-day mortality of the critically ill burn patients after burn surgery was 27.1% (198/731). RF showed the highest AUC (0.922, 95% confidence interval = 0.902-0.942) among the models, with sensitivity and specificity of 66.2% and 93.8%, respectively. The most significant predictors for mortality after burn surgery as per machine learning models were total body surface area burned, red cell distribution width, and age. The RF algorithm showed the best performance for predicting mortality.

18.
Nanomaterials (Basel) ; 12(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36500753

RESUMO

Owing to stringent international environmental and fuel efficiency requirements for lightweight automotive systems, polymer composites have attracted widespread attention. Polypropylene (PP) is a widely employed commercial polymer because of its lightweight and low cost. In this study, PP nanocomposites were fabricated to reduce the moisture absorption of PP composites in automotive headlamp housings. Alkylated chemically modified graphene (CMG-R) was synthesized to reduce the surface hydrophilicity of graphene and increase compatibility with the PP matrix. Fourier transform-infrared spectroscopy and scanning electron microscopy were performed to analyze the nanofillers. X-ray diffraction was performed to determine the interlayer spacing of the nanofiller resulting from surface treatment. Differential scanning calorimetry was used to analyze the crystallinity of the nanocomposites. The results indicated that the improved hydrophobicity of the nanofiller due to alkylation reduced the maximum moisture absorption of the PP nanocomposites by 15% compared to PP composites. The findings of this study are useful for reducing fogging in automotive headlamps.

19.
Arch Craniofac Surg ; 23(6): 269-273, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36596750

RESUMO

Naso-orbito-ethmoidal (NOE) fractures are complicated fractures of the mid-face. The treatment of NOE fractures is challenging and a comprehensive treatment strategy is required. We introduce a case of NOE fracture treated with open reduction and suspension sutures. A 28-year-old woman presented with a unilateral NOE fracture. To reduce the frontal process of the maxilla, a suspension suture was made by pulling the fragment using a double arm suture via a transcaruncular incision. The suture thread was placed in the horizontal plane. Another suspension suture on the inferior orbital rim assisted reduction procedure, and they passed through the overlying skin. The reduction alignment could be finely adjusted by tightening the transcutaneous suture threads while checking the degree of bone alignment through the subciliary incision. The two suture threads were suspended using a thermoplastic nasal splint. An additional skin incision on the medial canthal area, which would have resulted in a scar, could be avoided. Four months postoperatively, computed tomography showed an accurate and stable reduction. The patient was satisfied with her aesthetic appearance, and functional deficits were not present.

20.
Polymers (Basel) ; 14(6)2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35335470

RESUMO

Polyamide 46 (PA46) is used in various automotive parts because of its excellent heat resistance and mechanical properties. This study aims to improve the frictional properties of PA46 using the lubricating ability of graphene. Nanocomposites are prepared via two mixing methods: Graphene powder is compounded directly with PA46 pellets through a twin-screw extruder, or PA46 powder is added to graphene dispersion for self-adsorption, and subsequently, it is dried and compounded with PA46 through the twin-screw extruder. Application of the nanocomposite in the friction field is evaluated via the pin-on-disk method. The coefficient of friction of the nanocomposite prepared by self-adsorption is lower than that of the nanocomposite prepared by direct compounding. The mechanical properties of the nanocomposite fabricated by self-adsorption are superior to those of other materials. This can be attributed to the uniform dispersion of graphene and the strong attractive force between the PA46 matrix and graphene.

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