• The Journal of Advanced Prosthodontics
• /
• v.8 no.3
• /
• pp.207-213
• /
• 2016

PURPOSE. A recently introduced direct drill-guiding implant surgery system features minimal tolerance of surgical instruments in the metal sleeve by using shank-modified drills and a sleeve-incorporated stereolithographic guide template. The purpose of this study was to evaluate the accuracy of this new guided surgery system in partially edentulous patients using geometric analyses. MATERIALS AND METHODS. For the study, 21 implants were placed in 11 consecutive patients using the direct drill-guiding implant surgery system. The stereolithographic surgical guide was fabricated using cone-beam computed tomography, digital scanning, computer-aided design and computer-assisted manufacturing, and additive manufacturing processes. After surgery, the positional and angular deviations between planned and placed implants were measured at the abutment level using implant-planning software. The Kruskal-Wallis test and Mann-Whitney U test were used to compare the deviations (${\alpha}=.05$). RESULTS. The mean horizontal deviations were 0.593 mm (SD 0.238) mesiodistally and 0.691 mm (SD 0.344) buccolingually. The mean vertical deviation was 0.925 mm (SD 0.376) occlusogingivally. The vertical deviation was significantly larger than the horizontal deviation (P=.018). The mean angular deviation was 2.024 degrees (SD 0.942) mesiodistally and 2.390 degrees (SD 1.142) buccolingually. CONCLUSION. The direct drill-guiding implant surgery system demonstrates high accuracy in placing implants. Use of the drill shank as the guiding component is an effective way for reducing tolerance.

• Particle and aerosol research
• /
• v.7 no.4
• /
• pp.113-121
• /
• 2011

The aerosol nanoparticles are suspected to be exposed to workers in nanomaterial manufacturing facilities. However, the exposure assessment method has not been established. One of important issues is to characterize background level of nanoparticles in workplaces. In this study, intensive aerosol measurements were made at a $TiO_2$ manufacturing laboratory for five consecutive days in May of 2010. The $TiO_2$ nanoparticles were manufactured by the thermal-condensation process in a heated tube furnace. The particle number size distribution was measured using a scanning mobility particle sizer every 5 min, in order to detect particles ranging from 14.5 to 664 nm in diameter. Total particle number concentration shows a severe diurnal variation irrespective of manufacturing process, which was governed by nanoparticles smaller than 50 nm in diameter. During the background monitoring periods, significant peak concentrations were observed between 2 p.m. and 3 p.m. due to the infiltration of secondary aerosol particles formed by photochemical smog. Although significant increase in nanoparticle concentration was also observed during the manufacturing process twice among three times, these particle peak concentrations were lower than those observed during the background measurement. It is suggested that the investigation of background particle contamination is needed prior to conducting main exposure assessment in nanomaterial manufacturing workplaces or laboratories.

• International Journal of Vascular Biomedical Engineering
• /
• v.4 no.2
• /
• pp.25-30
• /
• 2006

We intended to measure the IT, MT, and the IMT of carotid artery separately and tried to analyze the clinical significance. Two hundred and fifty consecutive patients (125 males, 125 females) underwent carotid artery scanning using high-resolution ultrasound. The images were off-line analyzed using B-mode ultrasound image processing, devised in our research. We measured the IT, MT, and IMT semi-automatically at the far wall of designated 1cm length of the right common carotid and calculated the average values over the 200 points. The IT (p < 0.05), MT (p < 0.05) as well as IMT (p < 0.01) of patients with atherosclerotic disease were significantly thicker than that of the patients without atherosclerotic disease. Patients with hypertension showed significantly thicker IT (p < 0.05), MT (p < 0.01), and IMT (p < 0.01) than that of the patients without hypertension. However, only IT was thicker in patients with smoking (p < 0.05) than that of the patients without smoking. Smoking was associated only with intima while hypertension was associated with the all three layer's thickness. This result suggests the atherosclerotic process can be different by cardiovascular risk factors.

• Korean Journal of Ichthyology
• /
• v.27 no.3
• /
• pp.228-232
• /
• 2015

The structure of the ventricle in the heart of Hypomesus nipponensis was investigated by light and scanning electron microscope. The heart consisted of four consecutive chambers, the sinus venosus, atrium, ventricle and bulbus arteriosus. The wall of the ventricle was divided into endocardium, myocardium, subepicardium and epicardium. The valves were observed in the artrioventricular and bulboventricular junctions. The ventricular myocardium was an entirely spongy without coronary vessels. The trabecular network was formed with lumina included a central lumen and the trabecula was cylindrical shape. Collagen distribution was apparent in the subepicardium, artrioventricular valve and bulboventricular valve. But in the trabeculae, collagen distribution was observed partly in the base of the ventricle. Especially, the endocardial bridges were observed between trabeculae. These results might be considered that the structure of the ventricle in the heart of pond smelt is adapted to sedentary habit associated with its habitat and lifestyle.

• The Journal of Korean Physical Therapy
• /
• v.31 no.6
• /
• pp.358-362
• /
• 2019

Purpose: We investigated the difference in injury of the corticospinal tract (CST) and the spinothalamic tract (STT) in patients with putaminal hemorrhage, using diffusion tensor tractography (DTT). Methods: Thirty one consecutive patients with PH and 34 control subjects were recruited for this study. DTT scanning was performed at early stage of PH (7-63 days), and the CST and STT were reconstructed using the Functional Magnetic Resonance Imaging of Brain (FMRIB) Software Library program. Injury of the CST and STT was defined in terms of the configuration or abnormal DTT parameters was more than 2 standard deviations lower than that of normal control subjects. Results: Among 31 patients, all 31 patients (100%) had injury of the CTS, whereas 25 patients (80.6%) had injury of the STT: the incidence of CST injury was significantly higher than that of STT (p<0.05). In detail, 20 (64.5%) of 31 patients showed a discontinuation of the CST in the affected hemisphere; in contrast, 14 patients (45.2%) of 31 patients showed a discontinuation of the STT in the affected hemisphere. Regarding the FA value, 6 (19.4%) of 31 patients and 2 (6.4%) of 31 patients were found to have injury in the CST and STT, respectively. In terms of the fiber number, the same injury incidence was observed in 11 patients (35.5%) in both the CST and STT. Conclusion: The greater vulnerability of the CST appears to be ascribed to the anatomical characteristics; the CST is located anteriorly to the center of the putamen compared with the STT.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.19 no.6
• /
• pp.1585-1593
• /
• 2005

The genetic effects of restraint stress challenge on HPA axis and the therapeutic effect of Boshimgeonbi-tang on the stress were studied with cDNA microarray analyses, RT-PCR on hypothalamus using an immobilization-stress mice as an animal model. Male CD-1 mice were restrained in a tightly fitted and ventilated vinyl holder for 2hrs once a day, and this challenge was repeated for seven· consecutive days. In the change of body weight it showed that the Boshimgeonbi-tang is effected recovery on weight loss caused by the immobilization-stress. Seven days later, total RNA was extracted from the organs of the mouse, body-labeled with $CyDye^{TM}$ fluorescence dyes and then hybridized to CDNA microarray chip. Scanning and analyzing the array slides were carried out using GenePix4000 series scanner and GenePix $Pro^{TM}$ analyzing program, respectively. The expression profiles of 109 genes out of 6000 genes on the chip were significantly modulated in hypothalamus by the immobilization stress. Energy metabolism-, lipid metabolism-, apoptosis-, stress protein, transcriptional factor, and signal transduction-related genes were transcriptionally activated whereas DNA repair-, protein biosysthesis-, and structure integrity-related genes were down-regulated in hypothalamus. The 58 genes were up-regulated by the mRNA expression folds of 1.5 to 7.9. and the 51 genes were down-regulated by 1.5 - 5.5 fold. The 11 genes among them were selected to confirm the expression profiles by RT-PCR. The mRNA expression levels of Tnfrsf1a (apoptosis), Calm2 (cell cycle), Bag3 (apoptosis), Ogg1 (DNA repair), Aatk (apoptosis), Dffa (apoptosis), Fkbp5 (protein folding) were restored to the normal one by the treatment of Boshimgeonbi-tang.

• Journal of Korean Neurosurgical Society
• /
• v.48 no.6
• /
• pp.518-523
• /
• 2010

Objective : Chronic subdural hematoma (CSDH) is known to have a significant recurrence rate. There are different criteria defining the recurrence of CSDH. We evaluated the postoperative course of CSDH and tried to propose the reasonable criteria of recurrence. Methods : We retrospectively examined the medical records and pre- and postoperative CT scans of 149 consecutive patients who underwent surgery from January 2005 to December 2009. Diagnosis was confirmed by CT scanning or MRI. The postoperative courses were either resolved or recurrent. The resolved CSDH was one of the three types; early resolution, delayed resolution, or late resolution. The recurrent CSDH was one of the four types; recurrence without resolution, early recurrence after resolution, late recurrence after resolution, or recurrent-and-resolved type. Results : The CSDH was resolved within 30 days after surgery in 58 (39%) patients, between 1 to 3 months in 62 (42%), and after 3 months in 11 (7%) patients. The CSDH was recurred in 18 (12%) patients. Late resolution or recurrence was more common in the aged. The recurrent hematoma was seen on the same side in 11 patients, on the different side in 7 patients. Recurrence was significantly more common in the thick hematomas. Conclusion : For a working criteria of the recurrence of CSDH, we propose the early recurrence as return of symptoms or reaccumulation of the hematoma after a surgery within 3 months regardless of the location, amount or repeated operations. The late recurrence can be defined as reappearance or enlargement of a liquefied hematoma within the cranial cavity surrounded by the membranes or persistent CSDH beyond 3 months after surgery.

• Food Science of Animal Resources
• /
• v.36 no.6
• /
• pp.791-798
• /
• 2016

Free radicals may attack cells or tissue, leading to chronic diseases, and antioxidant consumption is potentially useful for removing free radicals. Egg proteins may be used as potential sources of antioxidant considering their ability of scavenging free radicals to apply for food or cosmetics industry. In this study, we obtained a natural antioxidant protein from fertilized eggs, which was a dietary supplement in some Asian countries. Meanwhile, antioxidant activities of these proteins were evaluated using different oxidation systems. With increasing incubation time, the antioxidant activity of these proteins increased during 15 d of incubation. The samples on day 15 were performed for isolation of antioxidant protein. The protein, named P4-1 (MW, 45 kDa), was isolated and purified by consecutive chromatographic methods. P4-1 contained 17 amino acids, which was determined by liquid chromatography-mass spectrometry and Amino Acid Analyzer. Moreover, the amino acid sequence was highly similar to that of ovalbumin. Differential scanning calorimetry showed that the denaturation temperature of P4-1 was $57.16^{\circ}C$. Furthermore, P4-1 suggested high oxygen radical-absorbance activity in ${\cdot}OH$ assays, and its antioxidant activity was stable at $30-50^{\circ}C$ in acidic and neutral pH. Thus, these results revealed that P4-1 may be a potential resource as a natural antioxidant.

• Korean Journal of Ophthalmology
• /
• v.32 no.6
• /
• pp.470-477
• /
• 2018

Purpose: To investigate the relationship between the progression of visual field (VF) loss and changes in lamina cribrosa depth (LCD) as determined by spectral-domain optical coherence tomography (SD-OCT) enhanced depth imaging in patients with primary open angle glaucoma (POAG). Methods: Data from 60 POAG patients (mean follow-up, $3.5{\pm}0.7$ years) were included in this retrospective study. The LCD was measured in the optic disc image using SD-OCT enhanced depth imaging scanning at each visit. Change in the LCD was considered to either 'increase' or 'decrease' when the differences between baseline and the latest two consecutive follow-up visits were greater than the corresponding reproducibility coefficient value ($23.08{\mu}m$, as determined in a preliminary reproducibility study). All participants were divided into three groups: increased LCD (ILCD), decreased LCD (DLCD), and no LCD change (NLCD). The Early Manifest Glaucoma Trial criteria were used to define VF deterioration. Kaplan-Meier survival analysis and Cox's proportional hazard models were performed to explore the relationship between VF progression and LCD change. Results: Of the 60 eyes examined, 35.0% (21 eyes), 28.3% (17 eyes), and 36.7% (22 eyes) were classified as the ILCD, DLCD, and NLCD groups, respectively. Kaplan-Meier survival analysis showed a greater cumulative probability of VF progression in the ILCD group than in the NLCD (p < 0.001) or DLCD groups (p = 0.018). Increased LCD was identified as the only risk factor for VF progression in the Cox proportional hazard models (hazard ratio, 1.008; 95% confidence interval, 1.000 to 1.015; p = 0.047). Conclusions: Increased LCD was associated with a greater possibility of VF progression. The quantitative measurement of LCD changes, determined by SD-OCT, is a potential biomarker for the prediction of VF deterioration in patients with POAG.

• Archives of Craniofacial Surgery
• /
• v.23 no.3
• /
• pp.103-110
• /
• 2022

Background: The primary objectives of mandibular surgery are to achieve optimal occlusion, low sensory disturbance, and adequate fixation with early movement. In-depth knowledge of the mandibular structure is required to achieve these goals. This study used computed tomography (CT) to evaluate the mandibular cortical thickness and cancellous space according to age and sex. Methods: We enrolled 230 consecutive patients, aged 20 to 50 years, who underwent CT scanning. The cortex and cancellous space centered around the inferior alveolar nerve (IAN) canal were measured at two specific locations: the lingula and second molar region. Statistical analysis of differences according to increasing age and sex was performed. Results: The t-test revealed that the cancellous space and cortical thickness differed significantly with respect to the threshold of 35 years of age. Both cortical thickness and cancellous space in the molar region were negatively correlated with age. Meanwhile, both cortical thickness and cancellous space in the lingula region showed a positive correlation with age. With respect to sex, significant differences in the cancellous space at the molar region and the cortical thickness at the lingula were observed. However, no further statistically significant differences were observed in other variables with respect to sex. The sum of each measurement on the mandibular body reflected the safe distance from the surface of the outer cortex to the IAN canal. The safe distances also showed statistically significant differences between those above and below 35 years of age. Conclusion: Knowledge of the anatomical structure of the mandible and of changes in bone structure is crucial to ensure optimal surgical outcomes and avoid damage to the IAN. CT examination is useful to identify changes in the bone structure, and these should be taken into account in the planning of surgery for older patients.