• Archives of Plastic Surgery
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• v.37 no.5
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• pp.712-716
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• 2010

Purpose: Extensive lumbosacral defects after removal of spinal tumors have a high risk of wound healing problems. Therefore it is an effective reconstructive strategy to provide preemptive soft tissue coverage at the time of initial spinal surgery, especially when there is an instrument exposure. For soft tissue reconstruction of a lumbosacral defect, a variation of the gluteal flap is the first-line choice. However, the musculocutaneous flap or muscle flap that is conventionally used, has many disadvantages. It damages gluteus muscle and causes functional disturbance in ambulation, has a short pedicle which limits areas of coverage, and can damage perforators, limiting further surgery that is usually necessary in spinal tumor patients. In this article, we present the superior gluteal artery perforator turn-over flap that reconstructs complex lumbosacral defects successfully, especially one that has instrument exposure, without damaging the ambulatory function of the patient. Methods: A 67 year old man presented with sacral sarcoma. Sacralectomy with L5 corpectomy was performed and resulted in a $15{\times}8\;cm$ sized complex soft tissue defect in the lumbosacral area. There was no defect in the skin. Sacral stabilization with alloplastic fibular bone graft and reconstruction plate was done and the instruments were exposed through the wound. A $18{\times}8\;cm$ sized superior gluteal artery perforator flap was designed based on the superior gluteal artery perforator and deepithelized. It was turned over 180 degrees into the lumbosacral dead space. Soft tissue from both sides of the wound was approximated over the flap and this provided in double padding over the instrument. Results: No complications such as hematoma, flap necrosis, or infection occurred. Until three months after the resection, functional disturbances in walking were not observed. The postoperative magnetic resonance imaging scan shows the flap volume was well maintained over the instrument. Conclusion: This superior gluteal artery perforator turn-over flap, a modification of the conventional superior gluteal artery perforator flap, is a simple method that enabled the successful reconstruction of a lumbosacral defect with instrument exposure without affecting ambulatory function.

• Journal of Periodontal and Implant Science
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• v.42 no.3
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• pp.88-94
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• 2012

Purpose: The use of appropriate instruments to clean surfaces with minimal change, is critical for the successful maintenance of a dental implant. However, there is no consensus about the type and methodology for such instruments. The aim of this study was to characterize changes in the roughness of titanium surfaces treated by various scaling instruments. Methods: Thirty-seven identical disks (5 mm in diameter) were investigated in this study. The specimens were divided into eight groups according to the types of instrumentation and the angle of application. Ultrasonic scaling systems were applied on a titanium disk to simulate standard clinical conditions. The equipment included a piezoelectric ultrasonic scaler with a newly developed metallic tip (NS group), a piezoelectric ultrasonic scaler with a conventional tip (CS group), a piezoelectric root planer ultrasonic scaler with a conventional tip (PR group), and a plastic hand curette (PH group). In addition, the sites treated using piezoelectric ultrasonic scaler systems were divided two sub-groups: 15 and 45 degrees. The treated titanium surfaces were observed by scanning electron microscopy (SEM), and the average surface roughness (Ra) and mean roughness profile depth (Rz) were measured with a profilometer. Results: SEM no significant changes in the titanium surfaces in the NS group, regardless of the angle of application. The PH group also showed no marked changes to the titanium surface, although some smoothening was observed. All CS and PR sites lost their original texture and showed irregular surfaces in SEM analysis. The profilometer analysis demonstrated that the roughness values (Ra and Rz) of the titanium surfaces increased in all, except the PH and NS groups, which showed roughness decreases relative to the untreated control group. The Ra value differed significantly between the NS and PR groups (P<0.05). Conclusions: The results of this study indicated that changes in or damage to titanium surfaces might be more affected by the hardness of the scaler tip than by the application method. Within the limitations of this study, the newly developed metallic scaler tip might be especially suitable for peri-implant surface decontamination, due to its limited effects on the titanium surface.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.36 no.5
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• pp.219-223
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• 2014

During surgical procedures, unexpected material, including surgical instruments and tissue segments, may get lost in the surgical field. Most of these should be immediately removed to prevent further complications, such as vital organ irritation, infection, and inflammatory pseudo-tumor formation. However, it is not always easy to define the exact location of the foreign body, especially if the item is very small and/or it is embedded in the soft tissue of the head and neck region. Intraoperative real-time radiological imaging with C-arm fluoroscopy can be useful to trace the three-dimensional location of small and embedded foreign bodies in the oral and maxillofacial area. We describe an unusual case of an embedded micro-screw in the intrinsic tongue muscle that had been dropped into the sublingual space during a lower alveolar bone graft procedure. The lost foreign body was accurately identified with C-arm fluoroscopy and safely removed without any further complications.

• Restorative Dentistry and Endodontics
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• v.35 no.4
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• pp.235-237
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• 2010

When curing the composite restorations with light curing units, the light guides are often in direct contact with oral tissues, therefore contamination of light guides is inevitable. Curing light guides fall into the "semicritical" instrument category according to the Centers for Disease Control and Prevention (CDC) and must be heat or vapor-sterilized or at a minimum, these semicritical instruments must be sterilized in a liquid chemical agent. Currently, most common methods of maintaining sterility of the light guides are wiping the guide with a disinfectant, such as glutaraldehyde, after each patient use; using autoclavable guides; using presterilized, single-use plastic guides; and using translucent disposable barriers to cover the guide.

• Archives of Plastic Surgery
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• v.39 no.5
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• pp.540-545
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• 2012

Background Patients have anxiety and fear of complications due to general anesthesia. Through new instruments and local anesthetic drugs, a variety of anesthetic methods have been introduced. These methods keep hospital costs down and save time for patients. In particular, the target-controlled infusion (TCI) system maintains a relatively accurate level of plasma concentration, so the depth of anesthesia can be adjusted more easily. We conducted this study to examine whether intravenous anesthesia using the TCI system with propofol and remifentanil would be an effective method of anesthesia in breast augmentation. Methods This study recruited 100 patients who underwent breast augmentation surgery from February to August 2011. Intravenous anesthesia was performed with 10 mg/mL propofol and 50 ${\mu}g/mL$ remifentanil simultaneously administered using two separate modules of a continuous computer-assisted TCI system. The average target concentration was set at 2 ${\mu}g/mL$ and 2 ng/mL for propofol and remifentanil, respectively, and titrated against clinical effect and vital signs. Oxygen saturation, electrocardiography, and respiratory status were continuously measured during surgery. Blood pressure was measured at 5-minute intervals. Information collected includes total duration of surgery, dose of drugs administered during surgery, memory about surgery, and side effects. Results Intraoperatively, there was transient hypotension in two cases and hypoxia in three cases. However, there were no serious complications due to anesthesia such as respiratory difficulty, deep vein thrombosis, or malignant hypertension, for which an endotracheal intubation or reversal agent would have been needed. All the patients were discharged on the day of surgery and able to ambulate normally. Conclusions Our results indicate that anesthetic methods, where the TCI of propofol and remifentanil is used, might replace general anesthesia with endotracheal intubation in breast augmentation surgery.

• Journal of the Korean Society for Precision Engineering
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• v.3 no.1
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• pp.69-76
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• 1986

The measuring Method by stylus, which measures surface roughness, has been widely used since G. Schmaltz developed the first equipment of that type. Withe the resent development of the measuring method by stylus, surface foughness testing instruments of the very high magnification ratio, hundreds of thousands, are manu- factured. However, as the techniques of the high precision roughness measurement are being required, the response problems due to the tip shapes and the plastic deformations of measured surface of mild material are to be serious factors. In this study, diamond stylus of tip radius $0.5\mu\textrm{m}$, $2\mu\textrm{m}$, $5\mu\textrm{m}$ and $10\mu\textrm{m}$ were used under the measuring force of 0.01gf, 0.02gf, 0.07gf, 0.4gf and 1.6gf, and from the experimental data, maximum measured value devrements between $2\mu\textrm{mR}$ stylus and $5\mu\textrm{mR}$ stylus, $2\mu\textrm{mR}$ stylus and $10\mu\textrm{mR}$ stylus are 22% and 31%, respectively when the measured value of $2\mu\textrm{mR}$ stylus goes to $0.01\mu\textrm{m Ra}$, $\lambda$ c2.5mm. And it is shown that plastic deformations on the plastic deformations on the measured surface are proportional to W/R(W;measured force, R;stylus tip radius).

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1907-1910
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• 2005

Coating thickness is an important variable that plays a role in product quality, process control, and cost control. Measurement of film thickness can be done with many different instruments. In this paper, we introduce the new eddy current system for measure the thickness of nonconductive coatings on nonferrous metal substrates. The experimental results are shown that the proposed system is able to measure thickness of plastic film coating on aluminum plates in the range of 0 to 1000 microns with satisfy sensitivities, linearity, resolution and stability of the system.

• Restorative Dentistry and Endodontics
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• v.7 no.1
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• pp.71-75
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• 1981

Five different labelled composite resin, Hypol (Korea), Glass-Ionomer (Japan), Simulate (U.S.A.), Durafil (U.S.A.) and Microfil (U.S.A.) were collected to employ for this experimental study. The purpose of the study is to determine the effect of finger pressure technic and traditional filling by means of plastic instruments on porosity formation in composite materials. Each material with pressure and non-pressure cases were carefully examined under electron microscope. Following were the results obtained through the study. 1. Pressured cases showed smaller number of porosity and the size of porosity was significantly smaller than non-pressured cases in each mateial. 2. Glass-Ionomer with pressure cases were seen as tube-like appearance because of pressured small porosities communicate in a certain direction. 3. Durafil cases both pressured and non pressured, appeared the least porosity formation. among the materiats. 4. Border line between the outmost periphery of the porosity and matrix of the resin in both pressured or non-pressured eases were found characteristically clear in Mierofil cases.

• Journal of Periodontal and Implant Science
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• v.49 no.3
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• pp.193-204
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• 2019

Purpose: The reaction of cells to a titanium implant depends on the surface characteristics of the implant which are affected by decontamination. The aim of this study was to evaluate the cytocompatibility of titanium disks treated with various decontamination methods, using salivary bacterial contamination with dental pellicle formation as an in vitro model. Methods: Sand-blasted and acid-etched (SA) titanium disks were used. Three control groups (pristine SA disks [SA group]; salivary pellicle-coated SA disks [pellicle group]; and biofilm-coated, untreated SA disks [NT group]) were not subjected to any decontamination treatments. Decontamination of the biofilm-coated disks was performed by 14 methods, including ultrasonic instruments, rotating instruments, an air-powder abrasive system, a laser, and chemical agents. MG63 cells were cultured in the presence of the treated disks. Cell proliferation assays were performed on days 2 and 5 of cell culture, and cell morphology was analyzed by immunofluorescence and scanning electron microscopy (SEM). A vascular endothelial growth factor (VEGF) assay was performed on day 5 of culture. Results: The cell proliferation assay revealed that all decontaminated disks, except for the 2 groups treated using a plastic tip, showed significantly less cell proliferation than the SA group. The immunofluorescence and SEM analyses revealed that most groups showed comparable cell density, with the exception of the NT group, in which the cell density was lower and bacterial residue was observed. Furthermore, the cells grown with tetracycline-treated titanium disks showed significantly lower VEGF production than those in the SA group. Conclusions: None of the decontamination methods resulted in cytocompatibility similar to that of pristine SA titanium. However, many methods caused improvement in the biocompatibility of the titanium disks in comparison with the biofilm-coated, untreated titanium disks. This suggests that decontamination is indispensable for the treatment of peri-implantitis, even if the original biocompatibility cannot be restored.

• Journal of the Korean Ceramic Society
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• v.39 no.11
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• pp.1048-1054
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• 2002

When forming the ceramic body with plastic mass, it is needed that a quantitative testing method for plasticity, not only to evaluate the plasticity of a body, but also to control it within limits. Although many testing instruments were introduced, but no handy testing instrument for the plasticity quantitatively has been developed. In this study, modified vicat needle was designed to handily evaluate the plasicity of extruding bodies for honeycomb. The plasticity of three plastic masses was tested with this equipment. Columned needle with 2 mm diameter was adopted to measure the resistance for deformation and spherical needle with 9.5 mm diameter was adopted to measure the amount of deformation before cracking. The plasticity of three tested bodies were clearly distinguished quantitatively each other and the testing results were helpful to evaluated the workability of theses bodies. Probably, it is possible to evaluate the plasticity of various ceramic bodies with this apparatus, if suitable diameters of columns and spheres are selected.