• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.6
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• pp.398-403
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• 2012

Purpose: Mandible resection and discontinuity defect created lead to aesthetic and functional problems. The iliac crest bone graft exhibits relative ease for bone harvesting, possibility of two team approach, ability to close the wound primarily, large amount of corticocancellous bone and relatively few complications. Whereas the use of free vascularized flaps has donor site morbidity and worse-fitting bone contour, the use of nonvascularized iliac bone graft has advantages in the operation time and patients' recovery time. So, nonvascularized iliac bone graft could be an attractive option. Methods: Twenty-one patients (M:F=1:1.1) underwent iliac crest bone harvesting for reconstruction of mandibular discontinuity defect (mean length : $61.6{\pm}17.8$ mm), from May 2005 to October 2011 at the Department of Oral and Maxillofacial Surgery in Kyungpook National University. The average age was $44.1{\pm}16.4$ years and the mean follow up periods was $28.2{\pm}22.7$ months. Bone resorption rate, according to age, sex, primary lesion, location and distance of defect, type of fixation plate, time of graft and pre-operative radiation therapy, were measured in each patient. Results: The mean bone resorption rate was $16.1{\pm}9.0%$. Bone resorption rate was significantly increased in mandibular defect that is over 6 cm in size (P=0.015, P<0.05) and the cases treated pre-operative radiation therapy (P=0.017, P<0.05). All was successfully fixed and maintained for the long-term follow-up. There were a few donor site complications and almost all patients were shown favorable outcome without severe bone resorption in this study. Conclusion: The nonvascularized iliac bone graft seems to be a reasonably reliable treatment option for reconstruction of mandibular discontinuity defects.

• Archives of Plastic Surgery
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• v.36 no.5
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• pp.578-582
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• 2009

Purpose: In extensive deep burn of the lower limb, due to less amount of soft tissue, bone is easily exposed. When it happens, natural healing or reconstruction with skin graft only is not easy. Local flap is difficult to success, because adjacent skins are burnt or skin grafted tissues. Muscle flap or free flap are also limited and has high failure rate due to deep tissue damage. The authors acquired good outcome by performing one - stage operation on bone exposed soft tissue defect with AlloDerm$^{(R)}$(LifeCell, USA), an acellular dermal matrix producted from cadaveric skin. Methods: We studied 14 bone exposed soft tissue defect patients from March 2002 to March 2009. Average age, sex, cause of burn, location of wound, duration of admission period, and postoperative complications were studied. We removed bony cortex with burring, until conforming pinpoint bone bleeding. Then rehydrated AlloDerm$^{(R)}$(25 / 1000 inches, meshed type) was applicated on wound, and thin split thickness(6 ~ 8 / 1000 inches) skin graft was done at the immediately same operative time. Results: Average age of patients was 53.6 years(25 years ~ 80 years, SD = 16.8), and 13 patients were male(male : female = 13 : 1). Flame burn was the largest number. (Flame burn 6, electric burn 3, contact burn 4, and scalding burn 1). Tibia(8) was the most affected site. (tibia 8, toe 4, malleolus 1, and metatarsal bone 1). Thin STSC with AlloDerm$^{(R)}$ took without additional surgery in 12 of 14 patients. Partial graft loss was shown on four cases. Two cases were small in size under $1{\times}1cm$, easily healed with simple dressing, and other two cases needed additional surgery. But in case of additional surgery, granulation tissue has easily formed, and simple patch graft on AlloDerm$^{(R)}$ was enough. Average duration of admission period of patients without additional surgery was 15 days(13 ~ 19 days). Conclusion: AlloDerm$^{(R)}$ and thin split thickness skin graft give us an advantage in short surgery time and less limitations in donor site than flap surgery. Postoperative scar is less than in conventional skin graft because of more firm restoration of dermal structure with AlloDerm$^{(R)}$. We propose that AlloDerm$^{(R)}$ and thin split thickness skin graft could be a solution to bone exposured soft tissue defects in extensive deep burned patients on lower extremities, especially when adjacent tissue cannot be used for flap due to extensive burn.

• The Korean Journal of Ceramics
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• v.7 no.1
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• pp.41-44
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• 2001

A composite of $Ca_3$(PO$_4$)$_2$ and MgAl$_2$O$_4$ spinel is biologically active and has enduring strength. Its strength depends on the spinel phase. The flaws in the spinel depend on the grain size of the calcium phosphate phase and are not altered by dissolution. The calcium phosphate, ${\alpha}$ tri-calcium phosphate, controls the tissue response. Bone bonds to the implant. A design for a bone graft as a replacement for a section of the diaphysis of a canine femur provides for tensile, compressive, torsional and bending load; and for the physiological processes of bonding and remodeling. A bone plate, used to stabilize the implant at time of surgery was removed after about one year. Over seven years of service have been achieved without internal or external fixation.

• Nuclear Engineering and Technology
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• v.52 no.2
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• pp.373-380
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• 2020

This study was carried out to convert the hydrophobic characteristics of PVDF to hydrophilic. Poly(-vinylidene fluorine) (PVDF) was grafted by electron beam irradiation and sulfonated. The grafting degree of modified PVDF increased with the monomer concentration, but not the conversion degree. From the results of FTIR and XPS, it was shown that the amount of converted sulfur increased with the grafting degree. The radiation-induced graft polymerization led to decrease fluorine from 35.7% to 21.3%. Meanwhile, the oxygen and sulfur content increased up to 8.1% and 3.2%. The pore size of modified membranes was shrunken and the roughness sharply decreased after irradiation. The ion exchange capacity and contact angle were investigated to show the characteristics of PVDF. The enhanced ion exchange capacity and lower contact angle of modified PVDF showed that the hydrophilicity played a role in determining membrane fouling. Electron beam irradiation successfully modified the hydrophobic characteristics of PVDF to hydrophilic.

• Journal of the Korean Arthroscopy Society
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• v.2 no.1
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• pp.25-32
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• 1998

The distinction between isolated and combined injuries is crucial both for treatment and prognosis. For most combined injuries, surgical treatment continues to be favored over nonoperative treatment. It is generally agreed that isolatel PCL injuries do well without surgery. There has been an interest by many authors to fix the graft directly to the posterior aspect of the tibia(tibial inlay). With this procedure, tibial graft fixation will be more direct and theoretically reduce the bending effects of the graft with a fixation site far away from the tibial insertion. Modified tibial inlay technique, which is the posterior approach does not require the patient to be in the prone or lateral decubitus position during the operation. Use of a double-bundle reconstructive technique is attractive and has been performed by some surgeons. At this time, this procedure is still being investigated and should not be routinely used in the clinical setting until studies have indicated an advantage over current single-bundle techniques. However theologically, double-bundle reconstructive technique is more useful in severe posterior unstable knee. Recent advances have increased our knowledge of the anatomy and mechanical characteristics of the PCL. Basic science research has further increased our awareness of the interaction of the posterolateral structures with the PCL. To achieve restoration of normal posterior laxity, it is critical to address the posterior as well as the postero-lateral structures. Surgical treatment is often complex and requires a wide range of surgical techniques and skills to treat associated injuries. When the PCL is reconstructed, most surgeons choose to reconstruct the anterolateral component using a graft of sufficient size and strength. The initial postoperative rehabilitation should be addressed cautiously in an effort to avoid excessive forces on delicate repairs and reconstructions in these complex injuries. Further research is necessary to evaluate new surgical approaches such as double-bundle reconstructions and tibial inlay techniques as well as improved techniques for capsular and collateral ligament injuries.

• Archives of Plastic Surgery
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• v.32 no.1
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• pp.117-123
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• 2005

The reconstructive modalities for vaginal reconstruction include simple dilatation, skin graft, use of intestinal segments and various methods using flaps. However, skin grafting procedure is the most commonly used technique and the McIndoe procedure is a representative technique among skin grafting procedures. McIndoe procedure is easier, faster and has a lower morbidity compared to other techniques. However the conventional McIndoe procedure has several problems such as incomplete vestibule formation, excessive bleeding during dissection, possibility of recto-vaginal or urethro-vaginal fistula formation, late vaginal contracture and discomfort in wearing hard plastic mold for a long time after operation. To solve these problems, the authors modified the conventional McIndoe procedure in several perspectives. The undeveloped vestibule was incised with X-shaped mucosal incision between the urethral opening and posterior margin of the vestibule and deepened by blunt finger dissection to provide a sufficient diameter & length of the neovagina and to minimize bleeding. A sizable medium thickness split skin graft was harvested and wrapped over a roll gauze-filled condom mold. Applying multiple stab incision on the skin grafted condom mold, it was inserted into the prepared neovaginal canal. Distal margin of the skin graft was secured with tips of the mucosal flaps created by X-shaped vestibular incision to prevent accidental extrusion of the skin grafted mold. During last 15 years, we applied this modification to 20 vaginal agenesis patients and investigated results of the 12 patients who could be followed up serially including hematoma formation and skin graft survival rate, size, depth, presence of late contracture, appearance, comfortness, and hygiene of the neovagina. And they were compared with 8 patients of 20 patients who underwent conventional McIndoe procedures. The modified McIndoe procedure revealed lower complication rate, higher patient satisfaction and better functional results.

• Journal of Periodontal and Implant Science
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• v.23 no.3
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• pp.422-441
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• 1993

The purpose of this study was to compare effects of the bioceramics on healing processes of the alveolar bone defects in dogs. Five adult dogs aged 1 to 2 years were used in this study. Experimental alveolar bone defects were created surgically with a #1/2 round bur at the furcation area of the buccal surface of the mandibular 3rd, 4th premolars and 1st molar. Fifteen experimental alveolar bone defects were devided into three groups according to the type of graft materials. The groups were as follows : 1) flap operation with dense hydroxyapatite( DHA group ) 2) flap operation with porous hydroxyapatite( PHA group ) 3) flap operation with natural coral ( NC group ) At 1, 2, 4, 6, and 12 weeks, dogs were serially sacrificed and specimens were prepared with Hematoxylin-Eosin stain and Mallory stain for light microscopic evaluation. The results of this study were as follows : 1. In every group, inflammatory cell infiltrations were seen at 1st weeks due to surgical trauma, however inflammatory response owing to graft materials were not seen. 2. In every group, the appearance of connective tissue around graft materials was loosely formed at the initial stages, however the connective tissue was densely formed at 2 weeks. 3. The presence of osteocytes were observed at 2 weeks in the natural coral group, however the osteocytes were appeared at 6weeks in the dense hydroxyapatite group. 4. A new bone was formed from the base and walls of the defect and gradually expanded toward the graft materials. 5. A resorption of the natural coral occurred irregularly at the periphery of the material, therefore the size and shape of the natural coral were reduced at 6 weeks. 6. At 12 weeks, the porous hydroxyapatite and natural coral were surrounded by newly formed bone most completely, however dense hydroxyapatite was surrounded by newly formed bone in part.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.3
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• pp.252-264
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• 1991

The purpose of this study was to compare the response of adjacent tissue and new bone formation after implantation by different methods of subperiosteal using using Proplast I and II in rabbit mandible. Microstructure of Proplast I and II was observed by scanning electron microscope. And the implantation procedure was carried out by dividing into tow groups, A and B. a group consisted of subperiosteal graft on the cortex, and the other B group was made up onlay graft following artificial decortication in the madibular body of rabbit. The experimental animals were sacrificed on the 1st, 2nd, 4th and 8th week after grafting for macroscopic and histopathologic examination. The samples extracted at the 6th postgrafting week were also used for biometric test. The result ere as follows : 1. By scanning electron microscopic observation, pore size was $50{\sim}180{\mu}m$ in the Proplast I and $100{\sim}220{\mu}m$ in Proplast II. 2. Macroscopically, infection of the graft site, deformation and displacement of the implanted materials were not observed in all experimental groups. 3. In the tissue response, infiltration of inflammatory cells and multinucleated giant cells were observed from the 2nd to the 8th week in Proplast I. Inflammatory cells decreased in number from the 2nd week in Proplast II suggesting that Proplast II is better than Proplast I. 4. Bone formation was not observed until the 8th week in the group A, but new bone formation from the surrounding graft bed and the periostium was appeared from the 4th week in the group B. 5. The maximum mean values of shear stress mere serially $65.5gf/mm^2$ in Proplast II of group B, $32.9gf/mm^2$ in Proplast I of group B, $17.0gf/mm^2$ in Proplast II of group A, and $15.7gf/mm^2$ in Proplast I. of group A.

• Archives of Craniofacial Surgery
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• v.20 no.2
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• pp.94-100
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• 2019

Background: Skin defects of head and neck need reconstruction using various local flaps. In some cases, surgeons should consider skin graft for large skin defect. It is important to heal skin graft and donor sites. The authors investigated wound healing mechanisms at the donor sites with split-thick-ness skin graft (STSG). In this study, the authors compared two types of immediate regraft including sheets and islands for the donor site after facial skin graft using remnant skin. Methods: The author reviewed 10 patients who underwent STSG, from March 2015 to May 2017, for skin defects in the craniofacial area. The donor site was immediately covered with the two types using remnant skin after harvesting skin onto the recipient site. Depending on the size of the remnant skin, we conducted regraft with the single sheet (n= 5) and island types (n= 5). Results: On postoperative day 1 and 3 months, the scar formation was evaluated using the Patient and Observer Scar Assessment Scale (POSAS) and Vancouver Scar Scale (VSS). Total POSAS and VSS scores for the island type were lower than in single sheet group after 3 months postoperatively. There was significant difference in specific categories of POSAS and VSS. Conclusion: This study showed a reduction in scar formation following immediate regrafting of the remnant skin at the donor site after STSG surgery. Particularly, the island type is useful for clinical application to facilitate healing of donor sites with STSG.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.4
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• pp.259-265
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• 2010

Purpose: This study was aimed to evaluate the effect of different sizes of $\beta$-TCP/ HA particles on vertical bone augmentation using titanium mesh in the cranium of rabbits. Materials and methods: Six white rabbits weighing 5kg were used. Four circular grooves of 6mm diameter were made by trephine, and five small holes were drilled in the inner surface of each circular gooves. Different sizes of grafts (small 0.3 - 0.5 mm, medium 0.5 - 1.0, large 1.0 - 2.0 mm) were placed respectively in the experimental groups. Titanium mesh (height 3 mm, width 6 mm) was placed. After 8weeks healing period, the rabbits were euthanized, and the specimens were prepared for histological findings. New bone formation and remaining graft area were measured to calculate the ratio of areas occupying the inner space of titanium mesh. Mann-Whitney U-test and Wilcoxon signed rank-test were used for statistical analysis ($\alpha$ = .05). Results: The experimental groups with $\beta$-TCP/HA graft showed a significantly higher new bone formation (P = .003). Comparing different sizes of $\beta$-TCP/HA, there was no statistical difference in terms of new bone formation. The vertical bone formation (i.e. new bone and graft area) was significantly greater in $\beta$-TCP/HA groups (P = .001). In comparison between different sizes of $\beta$-TCP/HA, medium size group had significantly greater area than large particle size group (P = .039). Conclusion: The use of $\beta$-TCP/HA with titanium mesh showed a higher vertical bone formation, particularly the medium sized $\beta$-TCP/HA particles (0.5 - 1.0 mm) produced better results in vertical bone augmentation.