• Title/Summary/Keyword: Defect potential

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Atypical Fibroxanthoma of Scalp Involving Occipital Bone (후두골을 침범한 두피의 비전형적 섬유황색종)

  • Jo, Yong Woo;Lim, So Young;Mun, Goo Hyun;Hyon, Won Sok;Bang, Sa Ik;Oh, Kap Sung
    • Archives of Plastic Surgery
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    • v.33 no.3
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    • pp.383-387
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    • 2006
  • Atypical fibroxanthoma is a pleomorphic spindle cell neoplasm characterized by a variable combination of cells with fibroblastic and histiocytic features. It occurs mostly on sun-exposed area of the head and neck of elderly person and is a clinically benign reactive lesion despite apparent malignant histologic features. However, because of its potential for metastasis, it is widely regarded as a low-grade sarcoma. We report a 30-year-old woman with atypical fibroxanthoma developed on the left occipital area. The lesion was $1.5{\times}2cm$ sized papule. There was no skin lesion such as ulcer or eschar. However, mass was involving occipital bone and composed of dense, pleomorphic spindle cells and several bizarre multinucleated giant cells. After wide excision of the scalp and occipital bone, the defect was covered with bone cement, bipedicled local flap and the donor site was covered with STSG. The wound healed completely without complication. It remained free of recurrence for a period of about 1 year follow up.

Evaluation of Abrasive Wear Face Using SAW (표면탄성파를 이용한 마모 표면부의 평가)

  • Kwon, Sung-D.;Yoon, Seok-S.;Song, Sung-J.;Lee, Young-Z.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.22 no.2
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    • pp.193-197
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    • 2002
  • The frequency dependency of the Rayleigh surface wave was investigated indirectly by measuring the angular dependency of the backward radiation of the incident ultrasonic wave in the abrasion specimens, which was explained in view of the residual stress distribution. The peak intensity of the backward radiation profile decreased and the right half width of the profile increased with an increase of the variational rate of residual stress for the scuffing specimen. The peak intensity was also affected by the surface wave scattering during the propagation around the micro-damages. The peak angle might depend on not only the amount of residual stress but also the micro-structure. The result observed in this study demonstrates the high potential of the backward radiated ultrasound as a tool for the nondestructive evaluation of the subsurface gradients of materials.

Influence of Coating Defect Ratio on Tribological Behavior Determined by Electrochemical Techniques (전기화학적 분석을 통해 산출된 코팅 결함율이 트라이볼로지적 특성에 미치는 영향 평가)

  • Lee Young-Ze;Kim Woo-Jung;Ahn Seung-Ho;Kim Ho-Gun;Kim Jung-Gu;Cho Chung-Woo
    • Tribology and Lubricants
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    • v.20 no.6
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    • pp.306-313
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    • 2004
  • Many of the current development in surface modification engineering are focused on multilayered coatings, which have the potential to improve the tribological properties. Four different multilayered coatings were deposited on AISI D2 steel in this study. The prepared samples are designed as $WC-Ti_{0.6}Al_{0.4}N,\;WC-Ti_{0.53}Al_{0.47}N,\;WC-Ti_{0.5}Al_{0.5}N\;and\;WC-Ti_{0.43}Al_{0.57}N$. The multilayered coatings were investigated with respect to coating surface and cross-sectional morphology, roughness, adhesion, hardness, porosity and tribological behaviors. Especially, wear tests of four multilayered coatings were performed by using a ball-on-disc configuration with a linear sliding speed of 0.017 m/sec and a normal load of 5.38 N load. The tests were carried out at room temperature in air by employing AISI 52100 steel ball $(H_R\;=\;66) $ having a diameter of 10 mm. The surface morphology, and topography of the wear scars of samples and balls have been determined by using scanning electron spectroscopy (SEM). Also, wear mechanism was determined by using SEM coupled with energy-dispersive spectroscopy (EDS). Results have showed an improved wear resistance of the $WC-Ti_{1-x}Al_xN$coatings with increasing of Al (aluminum) concentration.

The Effects of Addition Timing of NaCl and Sodium Tripolyphosphate and Cooking Rate on Pink Color in Cooked Ground Chicken Breasts

  • Bae, Su Min;Cho, Min Guk;Jeong, Jong Youn
    • Food Science of Animal Resources
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    • v.40 no.2
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    • pp.231-241
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    • 2020
  • The current study investigated the effects of timing of NaCl (2%) and sodium tripolyphosphate (STPP, 0.5%) addition and cooking rates on color and pigment properties of ground chicken breasts. Four treatments were tested as follows: treatment 1, no NaCl and STPP added and stored for 7 d; treatment 2, NaCl+STPP added on 0 d and stored for 7 d; treatment 3, NaCl added on 0 d and STPP added on 7 d; and treatment 4, stored for 7 d and NaCl+STPP added. All samples were cooked at a fast (5.67℃/min) or slow cooking rate (2.16℃/min). Regardless of the timing of NaCl and STPP addition, reflectance ratios of nitrosyl hemochrome, cooking yield, pH values, oxidation-reduction potential, and percent myoglobin denaturation were similar (p>0.05) across treatments 2, 3, and 4. The highest CIE a values were observed in treatment 4 (p<0.05), while treatment 2 was effective in reducing the redness in cooked chicken products. The fast cooking rate resulted in lower CIE a values and higher CIE L values and cooking yield in cooked chicken breasts compared to the slow cooking rate. Our results indicate that adding NaCl and STPP to meat, followed by storing and cooking at a fast rate, may result in inhibiting the pink color defect sporadically occurred in cooked ground chicken breasts.

Presalting Condition Effects on the Development of Pink Color in Cooked Ground Chicken Breasts

  • Bae, Su Min;Cho, Min Guk;Jeong, Jong Youn
    • Food Science of Animal Resources
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    • v.40 no.2
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    • pp.197-208
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    • 2020
  • The effects of presalting conditions (storage temperature and duration) with/without sodium tripolyphosphate (STPP) on the color and pigment characteristics of cooked ground chicken breast were investigated. Meat mixtures containing 2% NaCl (control) or 2% NaCl and 0.5% STPP (STPP treatment) were stored for 0, 3, 5, 7, and 10 d at 2℃ or 7℃, followed by cooking to 75℃, and cooling and storage at 2℃-3℃ until further analysis. The treatment was the most effective on the pink color defect of all independent variables. The effect of storage temperature was only observed on CIE L values and percentage myoglobin denaturation (PMD). The control was redder than the STPP treated samples and the CIE a values increased (p<0.05) from 0 to 5 d in the control and STPP treated samples. Compared to the STPP treatment, the control exhibited increased reducing conditions (more negative oxidation reduction potential), lower undenatured myoglobin, and greater PMD. No differences in the cooking yields of the control and STPP-treated samples were observed for various storage durations. Products with STPP showed higher (p<0.05) pH values than those without STPP, but no differences (p>0.05) in PMD were observed over the storage period in the control and STPP treated samples, except for day 0. Thus, STPP is effective at reducing the pink color in cooked chicken breasts. In addition, presalting for longer than 5 d resulted in increased pink color of the cooked chicken breasts.

The Effects of Graft of DFDB combined with Calcium Sulfate membrane on the Periodontal Wound Healing of Horizontal Dehiscence Defects in Dogs (성견 열개형 수평골 결손부에서 탈회냉동건조골과 Calcium Sulfate 차단막이 치주조직 치유에 미치는 영향)

  • Cho, Kyoo-Sung;Choi, Seong-Ho;Chai, Jung-Kiu;Moon, Ik-Sang;Kim, Chong-Kwan
    • Journal of Periodontal and Implant Science
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    • v.27 no.2
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    • pp.347-361
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    • 1997
  • The present study investigates the effects of DFDB graft combined with Calcium sulfate membrane on the periodontal wound healing in dehiscence defects of dogs. Following the initiation of general anesthesia by I.V. administration of 30mg/kg of pentobarbital, first premolar was extracted and full-thickness flap was elevated from the second to the fourth premolar. The portion of premolars coronal to the alveolar crest was removed and mesial and distal roots separated to produce single rooted teeth. Exposed root canals were sealed with Caviton and covered completely with flaps sutured. Following the healing period of 12 weeks, the surgical sites were uncovered and $4{\times}4mm$ dehiscence defects were surgically created. Those defects with DFDB graft combined with Calcium sulfate membrane following root planing, were designated as test sites and those with flap surgery-only were designated as controls. 1. No foreign-body reaction or inflammation were observed in either groups. Calcium sulfate was completely resorbed in the test sites. 2. Significantly greater amounts of new cementum was observed in test sites compared with the controls. Significant amounts of functionally orientated collagens were observed in the test sites. 3. New bone formation was observed in significantly greater amounts in test sites. The results suggest that combined graft of DFDB and calcium sulfate is extremely biocompatible with a potential for new bone and cementum formation, and functional alignment of periodontal ligaments.

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DIFFERENTIATION OF ADULT STEM CELL DERIVED FROM BUCCAL FAT PAD INTO OSTEOBLAST (협부지방에서 성체 줄기세포의 분리와 골모 세포로의 분화)

  • Pyo, Sung-Woon;Park, Jang-Woo;Lee, Il-Kyu;Kim, Chang-Hyen
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.32 no.6
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    • pp.524-529
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    • 2006
  • For the repairing of bone defect, autogenous or allogenic bone grafting remains the standard. However, these methods have numerous disadvantages including limited amount, donor site morbidity and spread of diseases. Tissue engineering technique by culturing stem cells may allow for a smart solution for this problem. Adipose tissue contains mesenchymal stem cells that can be differentiate into bone, cartilage, fat or muscle by exposing them to specific growth conditions. In this study, the authors procured the stem cell from buccal fat pad and differentiate them into osteoblast and are to examine the bone induction capacity. Buccal fat-derived cells (BFDC) were obtained from human buccal fat pad and cultured. BFDC were analyzed for presence of stem cell by immunofluorescent staining against CD-34, CD-105 and STRO-1. After BFDC were differentiated in osteogenic medium for three passages, their ability to differentiate into osteogenic pathway were checked by alkaline phosphatase (ALP) staining, Alizarin red staining and RT-PCR for osteocalcin (OC) gene expression. Immunofluorescent and biochemical assays demonstrated that BFDC might be a distinguished stem cells and mineralization was accompanied by increased activity or expression of ALP and OC. And calcium phosphate deposition was also detected in their extracelluar matrix. The current study supports the presence of stem cells within the buccal fat pad and the potential implications for human bone tissue engineering for maxillofacial reconstruction.

Full-Thickness Skin Grafting with De-Epithelization of the Wound Margin for Finger Defects with Bone or Tendon Exposure

  • Lee, Jun Hee;Burm, Jin Sik;Kang, Sang Yoon;Yang, Won Yong
    • Archives of Plastic Surgery
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    • v.42 no.3
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    • pp.334-340
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    • 2015
  • Background Full-thickness skin grafts (FTSGs) are generally considered unreliable for coverage of full-thickness finger defects with bone or tendon exposure, and there are few clinical reports of its use in this context. However, animal studies have shown that an FTSG can survive over an avascular area ranging up to 12 mm in diameter. In our experience, the width of the exposed bones or tendons in full-thickness finger defects is <7 mm. Therefore, we covered the bone- or tendon-exposed defects of 16 fingers of 10 patients with FTSGs. Methods The surgical objectives were healthy granulation tissue formation in the wound bed, marginal de-epithelization of the normal skin surrounding the defect, preservation of the subdermal plexus of the central graft, and partial excision of the dermis along the graft margin. The donor site was the mastoid for small defects and the groin for large defects. Results Most of the grafts (15 of 16 fingers) survived without significant surgical complications and achieved satisfactory functional and aesthetic results. Minor complications included partial graft loss in one patient, a minimal extension deformity in two patients, a depression deformity in one patient, and mild hyperpigmentation in four patients. Conclusions We observed excellent graft survival with this method with no additional surgical injury of the normal finger, satisfactory functional and aesthetic outcomes, and no need for secondary debulking procedures. Potential disadvantages include an insufficient volume of soft tissue and graft hyperpigmentation. Therefore, FTSGs may be an option for treatment of full-thickness finger defects with bone or tendon exposure.

Clinical Experience of Buccal Fat Pad Pedicled Flap for Denuded Area in Palatoplasty (입천장성형술 시 발생한 골 노출부의 피복을 위한 협지방대 유경피판의 경험)

  • Kim, Chee-Sun;Park, Myong-Chul;Park, Dong-Ha
    • Archives of Plastic Surgery
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    • v.37 no.1
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    • pp.31-36
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    • 2010
  • Purpose: The primary goal of palatoplasty is to enable normal speech with harmonious growth of face. Some children who had palatoplasty display typical findings of transverse maxillary deficiency requiring orthodontic widening of the maxilla. Levi (2009) described a cleft palate repair coupled with pedicled buccal fat pad flaps to cover bone exposed areas of the hard palate. Hence we report clinical experiences of cleft palate repair using pedicled buccal fat pad flap. Methods: Four Veau class II and a Veau class I cleft palate patients underwent palatoplasty with buccal fat pad flap by single surgeon from April 2009 to August 2009. Two patients received 2-flap palatoplasty and three patients 1-flap palatoplasty, respectively. After the cleft palate repair, sharp mosquito scissors was placed in the superior buccal sulcus just lateral to the maxillary tuberosity and inserted directly through the mucosa resulting in buccal fat pad extrusion. The elevated flap was moved to cover mucoperiosteal defect in hard palatal area. Results: Five patients underwent primary palatoplasty using buccal fat pad flap. Flap harvest and inset took on average 9 minutes per flap. Mucosal epithelization took 18 days on average. No patients had complications related to the buccal fat pad flap. Conclusion: Buccal fat pad pedicled flap has significant potential to function as an added vascularized tissue layer in cleft palate repair and we can expect better growth of maxilla with this method although longer duration of follow-up was unavailable.

Analysis of Color Difference in Facial Reconstruction used Various Flaps (안면부 재건술에서 사용되는 다양한 피판의 색조 비교)

  • Park, Jang Wan;Kim, Eui Sik;Hwang, Jae Ha;Kim, Kwang Seog;Lee, Sam Yong
    • Archives of Plastic Surgery
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    • v.36 no.4
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    • pp.365-371
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    • 2009
  • Purpose: Good color match holds a key position in facial reconstruction for good aesthetic result. To correct the wide facial soft tissue defect were usually used the tissue expanded cheek flap, deltopectoral flap or radial forearm free flap. This study is aimed to analyse the color difference after flap surgery by using chromameter. Method: From August 1995 to December 2006, 30 patients underwent flap operations were chosen randomly and evaluated color differences between flap site and adjacent skin. Reconstructive procedures included tissue expanded cheek flap(n = 10), deltopectoral flap(n = 10), and radial forearm free flap(n = 10). The measured sites were flap center within a radius of 1 ㎝ and four points of adjacent skin along the flap margin. The color was quantified in a three dimensional coordinate system $L^*$ (brightness), $a^*$ (redness), $b^*$ (yellowness). Results: There was no significant color difference between the pedicled flaps(tissue expanded cheek flap and deltopectoral flap) and adjacent skin area. On the other hand, color values of the radial forearm free flap were statistically different from those of adjacent skin area. Total color difference(${\Delta}E$) of tissue expanded cheek flap and deltopectoral flap were $7.45{\pm}5.78$ versus $9.41{\pm}7.09$, and that of radial forearm free flap was $11.74{\pm}3.85$. They suggest that pedicled flaps have a potential of better color match than radial forearm free flap. Conclusion: Thus, better esthetic result and satisfaction is more likely to be expected in pedicled flaps as long as it could be applied comparing radial forearm free flap.