• Title/Summary/Keyword: grafting technique

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Surface Modification of Polypropylene Membrane by ${\gamma}$ Irradiation Methods and their Solutes Permeation Behaviors

  • Shim, J. K.;Lee, S. H.;Kwon, O. H.;Lee, Y. M.;Nho, Y. C.
    • Proceedings of the Membrane Society of Korea Conference
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    • 1998.04a
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    • pp.99-101
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    • 1998
  • 1. Introduction : The conventional grafting polymerization technique requires chemically reactive groups on the surface as well as on the polymer chains. For this reason, a series of prefunctionalization steps are necessary for covalent grafting. The surface prefunctionalizational technique for grafting can be used to ionization radiation, UV, plasma, ion beam or chemical initiators. Of these techniques, radiation method is one of the useful methods because of uniform and rapid creation of active radical sites without catalytic contamination in grafted samples. If the diffusion of monomer into polymer is large enough to come to the inside of polymer substrate, a homogeneous and uniform grafting reaction can be carried out throughout the whole polymer substrate. Radiation-induced grafting method may attach specific functional moieties to a polymeric substrate, such as preirradiation and simultaneous irradiation. The former is irradiated at backbone polymer in vacuum or nitrogen gas and air, and then subsequent monomer grafting by trapped or peroxy radicals, while the latter is irradiated at backbone polymer in the presence of the monomer. Therefore, radiation-induced polymerization can be used to modification of the chemical and physical properties of the polymeric materials and has attracted considerable interest because it imparts desirable properties such as blood compatibility. membrane quality, ion excahnge, dyeability, protein adsorption, and immobilization of bioactive materials. Synthesizing biocompatible materials by radiation method such as preirradiation or simultaneous irradiation has often used $\gamma$-rays to graft hydrophilic monomers onto hydrophobic polymer substrates. In this work, in attempt to produce surfaces that show low levels of anti-fouling of bovine serum albumin(BSA) solutions, hydroxyethyl methacrylate(HEMA) was grafted polypropylene membrane surfaces by preirradiation technique. The anti-fouling effect of the polypropylene membrane after grafting was examined by permeation BSA solution.

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A systematic review of the scalp donor site for split-thickness skin grafting

  • Oh, Suk Joon
    • Archives of Plastic Surgery
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    • v.47 no.6
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    • pp.528-534
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    • 2020
  • Split-thickness skin grafting (STSG) is the gold standard for coverage of acute burns and reconstructive wounds. However, the choice of the donor site for STSG varies among surgeons, and the scalp represents a relatively under-utilized donor site. Understanding the validity of potential risks will assist in optimizing wound management. A comprehensive literature search was conducted of the PubMed database to identify studies evaluating scalp skin grafting in human subjects published between January 1, 1964 and December 31, 2019. Data were collected on early and late complications at the scalp donor site. In total, 27 articles comparing scalp donor site complications were included. The selected studies included analyses of acute burn patients only (21 of 27 articles), mean total body surface area (20 of 27), age distribution (22 of 27), sex (12 of 27), ethnicity (5 of 27), tumescent technique (21 of 27), depth setting of the dermatome (24 of 27), number of harvests (20 of 27), mean days of epithelization (18 of 27), and early and late complications (27 of 27). The total rate of early complications was 3.82% (117 of 3,062 patients). The total rate of late complications was 5.19% (159 of 3,062 patients). The literature on scalp skin grafting has not yet identified an ideal surgical technique for preventing donor site complications. Although scalp skin grafting provided superior outcomes with fewer donor site complications, there continues to be a lack of standardization. The use of scalp donor sites for STSG can prevent early and late complications if proper surgical planning, procedures, and postoperative care are performed.

Secondary bone grafting for alveolar clefts: surgical timing, graft materials, and evaluation methods

  • Kim, Junhyung;Jeong, Woonhyeok
    • Archives of Craniofacial Surgery
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    • v.23 no.2
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    • pp.53-58
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    • 2022
  • Alveolar cleft belongs to the spectrum of cleft lip and/or palate, affecting 75% of cleft lip/palate patients. The goals of alveolar cleft treatment are stabilizing the maxillary arch, separating the nasal and oral cavities, and providing bony support for both erupting teeth and the nasal base via the piriform aperture. Secondary alveolar bone grafting is a well-established treatment option for alveolar cleft. Secondary alveolar bone grafting is performed during the period of mixed dentition using autologous bone from various donor sites. There are several issues relevant to maximizing the success of secondary alveolar bone grafting, including the surgical timing, graft material, and surgical technique. In this study, we reviewed issues related to surgical timing, graft materials, and evaluation methods in secondary alveolar bone grafting.

Wrapping of an Ascending Aortic Aneurysm with the Multiple Boot-Straps Technique in a Patient Undergoing Off-Pump Coronary Artery Bypass Grafting

  • Na, Kwon Joong;Kim, Jun Sung;Park, Kay-Hyun;Lim, Cheong
    • Journal of Chest Surgery
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    • v.48 no.3
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    • pp.206-209
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    • 2015
  • Ascending aortic aneurysms are usually treated with graft replacement under cardiopulmonary bypass. However, if a candidate for off-pump coronary artery bypass grafting has an enlarged ascending aorta, surgeons may consider wrapping it without cardiopulmonary bypass. Here, we report a 78-year-old female who underwent successful wrapping of the ascending aorta concomitant with off-pump coronary artery bypass grafting, using a new wrapping technique that involves multiple bootstraps.

Inlay Grafting for the Treatment of the Posterior Comminuted Fracture of Medial Orbital Wall (Inlay법을 이용한 안와 내벽 골절의 교정)

  • Lim, Jong-Hyo;Kim, Tae-Gon;Lee, Jun-Ho;Kim, Yong-Ha
    • Archives of Craniofacial Surgery
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    • v.10 no.1
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    • pp.55-60
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    • 2009
  • Purpose: For blowout fracture of the medial orbital wall, the goals of treatment are complete reduction of the herniated soft tissue and anatomic reconstruction of the wall without surgical complications. Surgeons frequently worry about damage to the optic nerve from the dissection, when the part over the posterior ethmoidal foramen was fractured. The authors performed small incision and inlay grafting for reconstruction of medial orbital wall fracture. Methods: Between January 2007 and April 2008, 15 out of 32 patients were included in an analysing the outcome of corrected medial orbital wall fracture. In 15 patients of posterior comminuted fracture of medial orbital wall, insertion of porous polyethylene($Medpor^{(R)}$ channel implant, Porex, USA) to ethmoidal sinus was performed in multiple layer, through the transconjunctival approach (inlay grafting). Results: In all cases, the orbital bone volume was reconstructed in its normal anatomical position. The associated ocular problems disappeared except for mild enophthalmos in 2 patients and there were no surgical complications associated with inlay grafting. Conclusion: The advantage of inlay grafting include anatomical reconstruction of the orbital wall; the avoidance of optic nerve injury; the simplicity of the procedure; and consequently, the absence of surgery-related complications. This technique is presented as one of the preferred treatments for posterior comminuted fracture of medial orbital wall.

Ultrasound-guided Nerve Block for Skin Grafting on Large Diabetic Ulcer of Foot and Leg: A Technical Report (광범위 당뇨병성 족부 및 하퇴부 궤양의 피부이식술에 사용된 초음파 유도 신경 차단: 술기 보고)

  • Song, Jae-Hwang;Kang, Chan;Hwang, Deuk-Soo;Hwang, Jung-Mo
    • Journal of Korean Foot and Ankle Society
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    • v.18 no.3
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    • pp.133-136
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    • 2014
  • Skin grafting is often required for diabetic ulcerative foot lesions. In skin grafting, effective regional or local anesthesia into the donor and recipient areas plays a significant role in continuous control of pain. We report on a technique of ultrasound-guided nerve block on the femoral, sciatic, and lateral femoral cutaneous nerves in large split-thickness skin grafting for ulcer of the foot and leg.

CLINICAL EVALUATION OF PROGNOSIS OF OSSEOINTEGRATED DENTAL IMPLANT IN TREATMENT OF MAXILLARY EDENTULOUS AREA (골유착 치과 임플란트를 이용한 상악 무치악부 치료의 예후에 관한 임상적 평가)

  • Shim, Won-Bo;Lee, Dong-Keun;Choi, Kyu-Hwan
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.21 no.2
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    • pp.189-197
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    • 1999
  • The use of osseointegrated implant has been reported that is an acceptable procedure for the restoration of totally or partially edentulous patient and that offers good predictability of long term success. It is difficult to get high success rate in edentulous maxillae with inadequate bony quality and quantity, and anatomic limitations such as pneumatic maxillary sinus and nasal floor. The various trials such as sinus lifting, bone grafting, guided bone regeneration, trabecular condensation with osteotome, and the use of wide-diameter implant have been introduced to solve these problems. This study was undertaken to assess the evaluation of clinical prognosis of the implant restorations with these various implantation techniques in the maxillary edentulous area. One hundred eight patients were treated with a total of 386 endosseous implants from March 1994 to January 1998 at Dept. of Dentistry, Korea Veterans Hospital in Seoul Korea. The various techniques for implantation in the edentulous maxillae were supplied to overcome the limitations of implant fixation. These techniques consist of sinus lifting, guided bone regeneration, onlay bone grafting, and osteotome trabecular condensation technique. The total success rate of implant restoration of this study was 93% in the maxillae. The success rate of implant restorations with conventional technique was 94.6%, with osteotome trabecular condensation technique was 94.1%, with guided bone regeneration technique was 93.3%, with bone grafting technique was 92.9%, with sinus lifting technique was 83.8%. The success rate on the maxillary anterior area was 95.2% and that on the posterior area was 91.9%. The failures were associated not only with surgical installation techniques but also bony quality and quantity, characteristics of implant, and stress distribution when in function.

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AN ENGINEERING SCALE STUDY ON RADIATION GRAFTING OF POLYMERIC ADSORBENTS FOR RECOVERY OF HEAVY METAL IONS FROM SEAWATER

  • Prasad, T.L.;Saxena, A.K.;Tewari, P.K.;Sathiyamoorthy, D.
    • Nuclear Engineering and Technology
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    • v.41 no.8
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    • pp.1101-1108
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    • 2009
  • The ocean contains around eighty elements of the periodic table and uranium is also one among them, with a uniform concentration of 3.3 ppb and a relative abundance factor of 23. With a large coastline, India has a large stake in exploiting the 4 billion tonnes of uranium locked in seawater. The development of radiation grafting techniques, which are useful in incorporating the required functional groups, has led to more efficient adsorbent preparations in various geometrical configurations. Separation based on a polymeric adsorbent is becoming an increasingly popular technique for the extraction of trace heavy metals from seawater. Radiation grafting has provided definite advantages over chemical grafting. Studies related to thermally bonded non woven porous polypropylene fiber sheet substrate characterization and parameters to incorporate specific groups such as acrylonitrile (AN) into polymer back bones have been investigated. The grafted polyacrylonitrile chains were chemically modified to convert acrylonitrile group into an amidoxime group, a chelating group responsible for heavy metal uptake from seawater/brine. The present work has been undertaken to concentrate heavy metal ions from lean solutions from constant potential sources only. A scheme was designed and developed for investigation of the recovery of heavy metal ions such as uranium and vanadium from seawater.

"Off-Pump" Coronary rtery bypass Grafting in Multi-vessel Coronary Disease -Two Cases- (다중 혈관질환에서 심폐바이패스를 이용하지 않은 관상동맥 우회술)

  • 유원희;김기봉
    • Journal of Chest Surgery
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    • v.32 no.12
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    • pp.1123-1126
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    • 1999
  • Coronary artery bypass grafting (CABG) technique has been much developed but CABG under cardiopulmonary bypass has the unavoidable deficits such as generalized inflammatory reaction from cardiopulmonary bypass and myocardial ischemia from aortic-cross clamp. There has been remarkable advancement of CABG without cadiopulmonary bypass. We performed CABG successfully without cardiopulmonary bypass. We performed CABG successfully without cardiopulmonary bypass in two patients with multivessel coronary disease who were failed to intervene with percutaneous transluminal coronary angioplasty. We herein report the two cases.

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Experimental In-Vivo Models Used in Fat Grafting Research for Volume Augmentation in Soft Tissue Reconstruction

  • Lujan-Hernandez, Jorge;Appasani, Raghu;Sullivan, Kylee;Siegel-Reamer, Leah;Lalikos, Janice F.
    • Archives of Plastic Surgery
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    • v.44 no.5
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    • pp.361-369
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    • 2017
  • As the popularity of fat grafting research increases, animal models are being used as the source of pre-clinical experimental information for discovery and to enhance techniques. To date, animal models used in this research have not been compared to provide a standardized model. We analyzed publications from 1968-2015 to compare published accounts of animal models in fat grafting research. Data collected included: species used, graft characteristics (donor tissue, recipient area, amount injected, injection technique), time of sacrifice and quantification methods. Mice were most commonly used (56% of studies), with the "athymic nude" strain utilized most frequently (44%). Autologous fat was the most common source of grafted tissue (52%). Subcutaneous dorsum was the most common recipient site (51%). On average, $0.80{\pm}0.60mL$ of fat was grafted. A single bolus technique was used in 57% of studies. Fat volume assessment was typically completed at the end of the study, occurring at less than 1 week to one year. Graft volume was quantified by weight (63%), usually in conjunction with another analysis. The results demonstrate the current heterogeneity of animal models in this research. We propose that the research community reach a consensus to allow better comparison of techniques and results. One example is the model used in our laboratory and others; this model is described in detail. Eventually, larger animal models may better translate to the human condition but, given increased financial costs and animal facility capability, should be explored when data obtained from small animal studies is exhausted or inconclusive.