• Tribology and Lubricants
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• v.34 no.4
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• pp.146-159
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• 2018

This paper presents a wear analysis procedure for calculating the wear of journal bearings of a four-strokes and four-cylinder engine operating at a constant angular crank shaft speed during firing conditions. To decide whether the lubrication state of a journal bearing is in the possible region of wear scar, we utilize the concept of the centerline average surface roughness to define the most oil film thickness scarring wear (MOFTSW) on two rough surfaces. The wear volume is calculated from the wear depth and wear angle, determined by the magnitude of each film thickness on a set of oil films with thicknesses lower than the MOFTSW at every crank angle. To calculate the wear volume at one contact, the wear range ratio during one cycle is used. The total wear volume is then determined by accumulating the wear volume at every contact. The fractional film defect coefficient, asperity load sharing factor, and modified specific wear rate for the application of the mixed-elasto-hydrodynamic lubrication regime are used. The results of this study show that wear occurs only at the connecting-rod big-end bearing. Thus, simulation results of only the big-end bearing are illustrated and analyzed. It is shown that the wear volume of each wear scar group occurs consecutively as the crank angle changes, resulting in the total accumulated wear volume.

• Archives of Plastic Surgery
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• v.33 no.5
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• pp.531-535
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• 2006

Purpose: To report our experience of retro-angular flap for reconstruction of the midface defect. The midface, including nose, lower eyelid, and intercanthal area, is the very prominent area of face. Also midface is more vulnerable to trauma and skin cancer and defect of mid face of highly perceptible. Reconstruction of mid face is difficult because of complexity of anatomy and functions. Following factors should be considered in reconstructive prcedure of midface. First, multiple procedure may need for complete the reconstruction of mid face defect. Second, secondary reconstructive surgeries such as flap rotation or skin graft may need for donor site morbidity. Third, the color, texture and thickness of the skin used are not always complacency. Methods: 8 cases of the midface defects (3 cases of lower eyelid, 1 case of intercanthal area, and 4 cases of nose) from skin cancer were reconstructed with retroangular flap from March 2004 to August 2005. Results: Satisfactory result were obtained in color, texture and donor site scar. There was no major complication such as wound disruption, hematoma, and atrophy of flap. But partial necrosis of flap and bulkiness were observed one case in each. Retroangular flap is simple procedure that can be preceded in one stage under local anesthesia closing primary wound closure. It will leave less visible donor scar, acceptable color, texture and thickness of the skin. Conclusions: The retro-angular flap could be suggested as a safe and effective method for midface reconstruction.

• Archives of Plastic Surgery
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• v.32 no.2
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• pp.199-204
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• 2005

The nose is the most prominent area of the face, therefore susceptible to trauma and skin cancer. When small sized defect is in nasal tip, it results in disturbance of the facial harmony even if replantation, composite graft, skin graft or median forehead flap has been used for the reconstruction. So it is needed that the best method reconstruction is performed according to the degree of defect or deformity. And at the same time the physiology and anatomy of nose were clarified and its aesthetic subunits were employed. How can we cover the about 3 cm sized nasal defect in nasal tip with cartilage exposure? At first, we can think forehead island flap is most appropriate. We performed 7 cases of the forehead island flap for reconstruction of the defect in nasal tip(4 cases: cancer, 3 cases: trauma) from March, 2001 to August, 2004. This result was satisfactory in the point of texture, color, donor scar, and there were no complication such as wound disruption, infection, flap atrophy, and hematoma. The advantages of forehead island flap are: 1) No injury of deep vessel and nerve, 2) control of shape and volume, 3) Short operation time, 4) primary closure of donor site, 5) one stage operation. Also, forehead island flap can cover the defect in nose where skin graft and local flap can not cover. But, operator always must take care for flap congestion and donor site scar. We thought forehead island flap is one of the best option of reconstruction of nasal tip defect.

• Archives of Plastic Surgery
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• v.32 no.2
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• pp.262-266
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• 2005

In some blepharochalasis patients, upper blepharoplasty alone is not satisfactory because of narrow distance between eyebrow and eyelash. On that occasion, eyebrow lift is advisable. There are many methods of classical eyebrow lift, such as direct excision, transblepharoplasty approach, anterior hairline technique, and so on. But they are not so effective, have a tendency to recur and also give rise to side effects; unacceptable scar, facial nerve palsy, sensory loss and hematoma, etc. Some patients who have prominent nasolabial folds, are reluctant to perform face lift procedure due to psychologic or economic burden. The authors performed the eyebrow lift procedure separately or simultaneously with face lift or forehead lift. After making 2 or 3 slit incisions, we passed absorbable suture material, 3-0 vicryl, through suborbicularis oculi fat layer. Then it was passed through subperiosteal plane and fixated to the temporalis fascia. When patients complain prominent nasolabial folds, malar fat pad was elevated also in the same manner. This methods is effective and has minimal complication such as facial nerve palsy, scar, sensory loss. Recurrent tendency was rarely observed during follow-up. Dimples were observed at slit incision sites but they disappeared within 2 or 3 weeks. Eyebrow lift and malar fat lift by absorbable suture elevation with subperiosteal dissection is a simple and less morbid. Because of its effectiveness and little side effect or complication, this procedure can be a useful method.

• Archives of Plastic Surgery
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• v.43 no.2
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• pp.181-188
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• 2016

Background Major problems with cervicoplasty by direct skin excision include the subjective nature of skin markings preoperatively and the confusing array of procedures offered. This technique incorporates curved incisions, resulting in a wave-like scar, which is why the procedure is called a "wave-plasty". Methods This prospective study includes 37 patients who underwent wave-plasty procedures from 2004 to 2015. Skin pinching technique was used to mark the anterior neck preoperatively in a reproducible fashion. Intra-operatively, redundant skin was excised, along with excess fat when necessary, and closed to form a wave-shaped scar. Patients were asked to follow up at 1 week, 6 weeks, and 6 months after surgery. Results The mean operation time was 70.8 minutes. The majority (81.3%) was satisfied with their progress. On a scale of 1 to 10 (1 being the worst, and 10 being the best), the scars were objectively graded on average 5.5 when viewed from the front and 7.3 when seen from the side 6 months after surgery. Complications consisted of one partial wound dehiscence (2.3%), one incidence of hypertrophic scarring (2.3%), and two cases of under-resection requiring revision (5.4%). Conclusions In select patients, surgical rejuvenation of the neck may be obtained through wave-like incisions to remove redundant cervical skin when other options are not available. The technique is reproducible, easily teachable and carries low morbidity and high patient satisfaction in carefully chosen patients.

• Journal of the Korean Arthroscopy Society
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• v.4 no.1
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• pp.67-70
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• 2000

Osgood-Schlatter's disease is generally treated conservatively. However, surgical treatment is necessary for some patients with recurrent or persistent pain that does not respond to conservative treatment. Most authors recommend the excision of the loose ossicles present around the distal end of the patellar tendon. The authors report the technique of arthroscopic removal of the ossicles for Osgood-Schaltter's disease instead of the conventional technique through the incision at the tibial tuberosity. The advantages of this technique are less damage to the patellar tendon, early postoperative recovery, making no incisional scar in front of the tuberosity which causes the scar discomfort in kneeling, and more cosmetic result.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.2
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• pp.203-216
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• 1991

Nerve allografts as a bridge of regeneration is useful in the repair of peripheral nerve defect resulting from trauma, and leprosy. But immunological rejection and complicated scar formation is an unavoidable problem in the application of allogeneic nerves. This article is intended to study of the regeneration of allogeneic nerve grafts in rats with histopathologically, scanning electron microscopically. 24 adult male Sprague-Dawley rats were used as the experimental animals. A 2cm skin incision was made on the lateral aspects of limb, parallel to femur. Segments of sciatic nerve trunk taken from rats, 10mm was resected at the middle of the thigh, nerve graft was inserted between the ends of gaps with perineural and epineural suture method with 10-0 prolene. Obsrevation was made simultaneously at 3 day, 1, 2, 3, 4, 5, 6, 8 weeks after surgery. The results were as follows. 1. In light and electronic microscopic studies, marked degenerative change of the graft nerves were observed at 2 weeks after surgery. 2. After surgery, blood clot fromation was observed at 3 day, granualtion tissue formation was observed at 2 week, and fibrous tissue proliferation was observed at 3 week. 3. In change of nerve fiber, there were Wallerian degeneration at early stage, decrease in degeneration at 4 week but degeneration of myeline was continuded at 8 week. 4. At 4 week, schwann cells proliferate at its cut ends to join with the distal and proximal stump of the damaged nerve. 5. Fibrous scar tissues are formed at 2 weeks and increased progressively in 8 weeks, which was interrupted the regeneration of grafted nerve.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.2
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• pp.254-261
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• 2000

Since callus distraction technique was applied clinically for the correction of dentofacial deformity to the patients with hemifacial dysplasia by McCarthy in 1992, many surgeons have tried to apply this method to the maxillofacial region. But this technique has some drawbacks. One of the disadvantages of this technique is extensive scar formation in the facial area, which is a sequelae of extraoral approach for supraperiosteal dissection of the periosteum overlying the mandible. Recently, we have made an effort to perform this technique through intraoral approaches to prevent scar formation on the submandibular area and modified the design of the osteotomy, that is step osteotomy technique, to increase the raw bone surface on both osteotomized segments. The rationale for the application of this step osteotomy technique is to increase the amount of regenerated bone and the length of distraction, to avoid damage of inferior alveolar neurovascular bundle, and to increase initial stability of the splitted segments. Step osteotomy procedure can be done with fine micro-osteotomy saw through subperiosteal tunneling. Extraoral pins should be inserted before making the osteotomy. Since 1994 we have applied this technique at 8 sites In 5 patients with mandibular deficiencies: 2 cases of hemifacial microsomia, 1 case of developmental facial asymmetry and 2 cases of mandibular bony defect. Mandibular elongation have been achieved from 12 to 20mm in length. 1 out of 8 site, we experienced non-union in the case of mandibular body defect. Some skeletal relapse and growth retardation phenomenon have been observed in some cases with the longest follow-up of 48 months.

• Journal of Korean Foot and Ankle Society
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• v.21 no.4
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• pp.151-155
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• 2017

Purpose: Reducing tenderness or pain on the ankle joint and improving the range of motion are thought to be possible using hyaluronate-based anti-adhesive agents. On the other hand, there are more aspects to be studied regarding the incidence of complications, such as resting pain, tenderness, and stiffness, after surgery. Therefore, the aim of this study was to prove the effectiveness of the agents after ankle fracture surgery. Materials and Methods: Patients, who underwent open reduction and internal fixation surgery due to ankle joint fractures from June 2015 to May 2016, were studied prospectively. Thirty patients of them received a $Guardix^{(R)}$ injection during their surgeries and were included in the injection group. The other 30 patients were included in the control group. Postoperatively, tenderness on the scar, a delay in wound healing, and the active range of motion were evaluated at 2, 6, and 12 weeks after surgery. Results: A significant difference in tenderness on the scar was observed 2 weeks after surgery. On the other hand, there was no significant difference at 6 and 12 weeks after the surgery. The agent-using group showed a 6.7% delay in wound healing and a 93.3% nondelaying. In the non-using group, the delay was 63.3%, while non-delay was 36.7% (p<0.001). The group that underwent $Guardix^{(R)}$ usage showed an effective result in the visual analogue scale, which was statistically significant (p<0.001). The result at 6 and 12 weeks after surgery showed a significant difference. Conclusion: Improvement was observed in the patients who underwent a $Guardix^{(R)}$ injection, regarding the range of motion, visual analog scale, and healing of the wound postoperatively.

• Molecules and Cells
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• v.25 no.2
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• pp.205-210
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• 2008

To develop molecular markers linked to the $L^4$ locus conferring resistance to tobamovirus pathotypes in pepper plants, we performed AFLP with 512 primer combinations for susceptible (S pool) and resistant (R pool) DNA bulks against pathotype 1.2 of pepper mild mottle virus. Each bulk was made by pooling the DNA of five homozygous individuals from a T10 population, which was a near-isogenic $BC_4F_2$ generation for the $L^4$ locus. A total of 19 primer pairs produced scorable bands in the R pool. Further screening with these primer pairs was done on DNA bulks from T102, a $BC_{10}F_2$ derived from T10 by back crossing. Three AFLP markers were finally selected and designated L4-a, L4-b and L4-c. L4-a and L4-c each underwent one recombination event, whereas no recombination for L4-b was seen in 20 individuals of each DNA bulk. Linkage analysis of these markers in 112 $F_2$ T102 individuals showed that they were each within 2.5 cM of the $L^4$ locus. L4-b was successfully converted into a simple 340-bp SCAR marker, designated L4SC340, which mapped 1.8 cM from the $L^4$ locus in T102 and 0.9 cM in another $BC_{10}F_2$ population, T101. We believe that this newly characterized marker will improve selection of tobamovirus resistance in pepper plants by reducing breeding cost and time.