• Restorative Dentistry and Endodontics
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• v.26 no.1
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• pp.16-22
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• 2001

The purpose of this study was to evaluate the marginal microleakage of condensable composite resin restorations according to flowable resin lining of internal cavity wall. The eighty extracted human molar teeth without caries and/or restorations are used The experimental teeth were randomly assigned into four groups of ten teeth each. Eighty caries-free extracted human molars were used in this study. The conventional class II cavities (box-shaped on mesial and distal surface, faciolingual width : 3mm, gingival wall depth : 1.5mm) were prepared 1mm below cementoenamel junction with a # 701 carbide bur. The teeth were divided into four groups, and then each group were subdivided into A & B group according to flowable resin & compomer lining ; Group 1-A : Tetric Ceram filling, Group 1-B : Tetric Flow lining and Tetric Ceram filling, Group 2-A Ariston pHc filling, Group 2-B : Tetric Flow lining and Ariston pHc filing, Group 3-A SureFil filling, Group 3-B : Dyract Flow lining and SureFil filling, Group 4-A : Pyramid filling, Group 4-B : Aeliteflo lining and Pyramid filling. To simulate as closely as possible the clinical situation during retoration placement, a "restoration template" was fabricated, and the condensable resin was filled using a three-sited light-curing incremental technique. All the materials used were applied according to the manufacturers' instructions. The specimens were stored in the 100% humidity for 7 days prior to thermocycling (100 thermal cycles of 5~55$^{\circ}C$ water with a 30-second dwell time) The specimens were immersed in 2% metyleneblue dye for 24 hours, and then embedded in transparent acrylic resin and sectioned mesiodistally with diamond wheel saw. The degree of marginal leakage was scored under stereomicroscope ($\times$20) and the data were analyzed by Kruskal-Wallis test and Wilcoxon signed ranks test. The results were as follows : 1. In the gingival margins of all the group, microleakage of subgroup B was less than subgroup A. 2. In the group 1, 2, 4, there was significant differences between subgroup A and B (p<0.05), but in the group 3, there was not significant different between group 3-A (SureFil) and group 3-B (Dyract flow/SureFil) (p>0.05). 3. In the subgroup A and B, there was significant different between all group except group 4 of subgroup A. From the results above, it was suggested that the cavity lining of flowable resin and flowable compomer in condensable resin restoration decrease microleakage at gingival margin, and does improve their ability to seal the gingival margin of class II preparation.

• Journal of the Korean Society of Radiology
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• v.82 no.1
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• pp.128-138
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• 2021

Purpose We evaluated the risk factors for progression to chronic complicated bronchopleural fistula (BPF) after pulmonary resection using follow-up CT. Materials and Methods We retrospectively reviewed 45 cases with BPF that had undergone pulmonary resection during 2010-2018. We compared the clinical and radiological characteristics of those with complicated BPF (n = 24) and those without complicated (sterilized) BPF (n = 21). The clinical and radiological risk factors for progression to chronic complicated BPF were examined by logistic regression analysis. Results The thickness of the pleural cavity wall (p = 0.022), the size of the pleural cavity (p = 0.029), and the size increase of BPF on follow-up (p = 0.012) were significantly different between the two groups. The risk factors for progression to chronic complicated BPF were age > 70 years (odds ratio, 6.43; 95% confidence interval, 1.2-33.7), the thickness of the cavity wall > 5 mm (odds ratio, 52.5; 95% confidence interval, 5.1-545.4), and an increase in the size of the pleural cavity on follow-up CT (odds ratio, 12.5; 95% confidence interval, 2.1-73.5), only in the univariate analysis. Conclusion The risk factors for progression to chronic complicated BPF can be evaluated using follow-up CT.

• Restorative Dentistry and Endodontics
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• v.24 no.1
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• pp.166-179
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• 1999

Apical sealing is essential for the success of surgical endodontic treatment. Root-end cavity is apt to be contaminated with moisture or blood, and is not always easy to be dried completely. The purpose of this study was to evaluate the influence of dry methods of retrocavity on the apical seal in endodontic surgery. Apical seal was investigated through the evaluation of apical leakage and adaptation of filling material over the cavity wall. To investigate the influence of various dry methods on the apical leakage, 125 palatal roots of extracted human maxillary molar teeth were used. The clinical crown of each tooth was removed at 10 mm from the root apex using a slow-speed diamond saw and water spray. Root canals of the all the specimens were prepared with step-back technique and filled with gutta-percha by lateral condensation method. After removing of the coronal 2 mm of filling material, the access cavities were closed with Cavit$^{(R)}$. Two coats of nail polish were applied to the external surface of each root. Apical three millimeters of each root was resected perpendicular to the long axis of the root with a diamond saw. Class I retrograde cavities were prepared with ultrasonic instruments. Retrocavities were washed with physiologic saline solution and dried with various methods or contaminated with human blood. Retrocavities were filled either with IRM, Super EBA or composite resin. All the specimens were immersed in 2% methylene blue solution for 7 days in an incubator at $37^{\circ}C$. The teeth were dissolved in 14 ml of 35% nitric acid solution and the dye present within the root canal system was returned to solution. The leakage of dye was quantitatively measured via spectrophotometric method. The obtained data were analysed statistically using one-way ANOVA and Duncan's Multiple Range Test. To evaluate the influence of various dry methods on the adaptation of filling material over the cavity wall, 12 palatal roots of extracted human maxillary molar teeth were used. After all the roots were prepared and filled, and retrograde cavities were made and filled as above, roots were sectioned longitudinally. Filling-dentin interface of cut surfaces were examined by scanning electron microscope. The results were as follows: 1. Cavities dried with paper point or compressed air showed less leakage than those dried with cotton pellet in Super EBA filled cavity (p<0.05). However, there was no difference between paper point- and compressed air-dried cavities. 2. When cavities were dried with compressed air, dentin-bonded composite resin-filled cavities showed less apical leakage than IRM- or Super EBA-filled ones (p<0.05). 3. Regardless of the filling material, cavities contaminated with human blood showed significantly more apical leakage than those dried with compressed air after saline irrigation (p<0.05). 4. Outer half of the cavity showed larger dentin-filling interface gap than inner half did when cavities were filled with IRM or Super EBA. 5. In all the filling material groups, cavities contaminated with blood or dried with cotton pellets only showed larger defects at the base of the cavity than ones dried with paper points or compressed air.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.488-492
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• 2003

Yeast cell wall mutant, Saccharomyces cerevisiae IS2 was screened by the NTG treatment of Saccharomyces cerevisiae KCTC 7911. The mutant was highly resistant to zymolase, which specifically degrades ${\beta}$-1,3-D-glucose chain of ${\beta}$-glucan and mechanical disruption by glass beads. These phenomena demonstrate that the yeast mutant has cell wall structure different from the wild-type. The ${\beta}$-glucan of yeast mutant and wild-type strains was recovered by sequential extraction with NaOH. The injection of ${\beta}$-glucan into the abdominal cavity of mouse resulted in an increase in the number of peritoneal immune cells, NO (nitric oxide) production, and phagocytic activity of macrophage. The number of immune cells was found to be $3.90{\times}10^6\;cells/10\;mL$ and $5.48{\times}10^6\;cells/10\;mL$ with the wild-type and mutant ${\beta}$-glucan, respectively. The effect on the NO production and phagocytic activity of mutant ${\beta}$-glucan were 1.69 and 1.43-fold higher than those of wild-type. These results indicate that the immuno-stimulating activity of alternated ${\beta}$-glucan from mutant yeast is higher than that of wild-type.

• Journal of Oral Medicine and Pain
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• v.30 no.4
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• pp.457-464
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• 2005

The purpose of our study was to investigate whether the intrapulpal temperature during cavity preparation of enamel or dentin with Er:YAG laser still remained in range of safety for dental pulp protection when combined with appropriate water flow rate. The effect of different pulse repetition rates at the same pulse energy during ablation was evaluated as well. Caries-free, restoration-free extracted human molar teeth were prepared for the specimen and divided two experimental groups of enamel and dentin. Each group comprised 5 specimens and each of tooth specimens were embedded into a resin block each and measuring probe was placed on the irradiated pulpal walls. For experiments of dentin ablation, enamel layers were prepared to produce dentin specimen with a same dentin thickness of 2 mm. A pulse energy of Er:YAG laser was set to 300 mJ and three different pulse repetition rates of 20 Hz, 15 Hz and 10 Hz were employed. Laser beam was delivered with 3 seconds and less per application over enamel and dentin surfaces constant sized by $3\;mm{\times}2\;mm$ and water spray added during irradiation was a rate of 1.6 ml/min. Temperature change induced by Er:YAG laser irradiation was monitored and recorded While enamel was ablated, there was no significant difference of temperature related to pulse repetition rates(p=0.358) and temperature change at any pulse repetition rate was negligible. Significant statistical difference in temperature changes during cavity preparation in dentin existed among three different pulse groups(p=0.001). While temperature rise was noticeable when the dentinal wall was perforated, actual change of temperature due to Er:YAG laser irradiation was not enough to compromise safety of dental pulp when irradiation was conjugated with appropriate water spray. Conclusively, it can be said that cavity preparation on enamel or dentin with an Er:YAG laser is performed safely without pulp damage if appropriate volume of water is sprayed properly over the irradiated site.

• Journal of Korean Neurosurgical Society
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• v.53 no.4
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• pp.218-222
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• 2013

Objective : To clarify the anatomical correlations of the sphenoid sinus with surrounding structures in the normal Korean population, and to identify surgical landmarks for safe sellar floor dissection in the anterior skull base by endoscopy and microscopy. Methods : We reviewed the 196 brain magnetic resonance imaging findings showing a normal appearance, and measured the distances between anatomical landmarks. Results : The mean distances from the base of the columella to the anterior wall of the sphenoid sinus and the sellar floor were $69.71{\pm}4.25$ mm and $86.26{\pm}4.57$ mm, respectively in the over 15 age group, and showed the smallest degree of variation among the measurements. The mean angles between the floor of the nasal cavity and the straight line connecting the base of the columella and the sellar floor were $29.45{\pm}3.25^{\circ}$ and $24.75{\pm}4.00^{\circ}$ in the over 15 and under 15 age groups, respectively. The mean values of both distances and angles increased with age until 15 years after which no further increases were evident. There were no significant differences in the measurements between males and females or among subjects with different degrees of pneumatization in the over 15 age group. Conclusion : The distances from the base of the columella to the sellar floor and the anterior wall of the sphenoid sinus, which were consistent among individuals, could be used as a surgical indicator to investigate the sellar floor in endoscopic or microscopic transsphenoidal approaches.

• Applied Microscopy
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• v.23 no.1
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• pp.91-108
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• 1993

The relationship of cartilage canals to initial osteogenesis of primary ossification center of developing vertebrae in human fetuses ranging from 50mm to 260mm in crown rump length was studied by light and electron microscopy. The cartiage canals of the thoracic vertebrae were first observed at 60mm fetus. Cartilage canals were identified as vascular channels arising from perichondrium surfaces. A number of cartilage canals were observed around the primary center of ossification at 80mm fetus. At 120mm fetus, cartilage canals of the bodies of vertebra were increased. Eventually the canals were eroded from the main medullary cavity and remained at only peripheral regions of growth cartilage. Superficial, intermediate, and deep canals were identified by the characteristics of cartilage cells. Fibroblasts, undifferentiated mesenchymal cells, and vacuolated macrophages were observed adjacent to the matrix of resting cartilage cells in the superficial canal. Fibroblasts and mesenchymal cells were densely packed at the tip of canal, giving an epithelial appearance to the clustered cell in the intermediate canal. Vacuolated macrophages were in contact with matrix of hypertrophied cartilage. The thick-walled vessels in the intermediate and deep canals consisted of typical endothelial cells, but in the newly formed vessels contained mesenchymal cells and fibroblasts incorporated into the vessel wall. During lengthening of cartilage canal, the matrix of cartilage cells were invaded by newly formed capillaries and vacuolated macrophages. At the deep canal, the lateral wall of the canal terminated in matrix containing calcified cartilage. The mesenchymal cells began to differentiate into osteoblasts adjacent to the calcified matrix. The results indicate that the connective tissue cells within the cartilage canals proliferate and differentiate into osteoblasts at the site of primary ossification center.

• The Korean Journal of Malacology
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• v.7 no.1
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• pp.76-86
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• 1991

A scanning electron microscopic stuey on the glochidial encystment study on the golchidal encystment and excystment of Anodonta fukudai on Acheilognathus yamatsutae, a common natural hostfish, was conducted. The glochidium easily attached to the unscaled surfaces of the host fish such as the fins, lips, and the wall of the buccal cavity. For this study, the fins infected with the glochidia wer mainly observed in a series. The process of encystment was slowly progressed, for 21-25 hours for the early cyst and for 2-4 days for the thick walled cyst. The process of excystmint was visually detected on the 12th day since the attachmint was occurred. The first visible sign was a little tear of the cyst wall covering the hinge and marginal zones of the juvenile clam and once the little sign was appeared the progress of emerging and dettachmint of the juvenile clam from the host was finished relatively in short time. During the process of the encystmint, the cells participationg in covering the attached glochidirm were seened mainly supplied by migration from the surroundings. the shapes of the cells migrating and covering the glochidium were considerably changed and the surface structures of the cells lost their normal pattern of the surface ridges. The unstable forms of the cells were observed almost all throughout the period of the glochidial attachment. No cells of the host epithelium, which were still attached to the juvenile clam energing from the cyst, were observed. The most juvenile clams escaped from the cysts were a little bigger than the glochidia and they were still possessed of the golchidial hooks even though much degenerated. The first growth line was appeared on the shell valves of the juvenild clam when observed right after dettachment.

• Archives of Plastic Surgery
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• v.35 no.6
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• pp.743-747
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• 2008

Purpose: Malignant changes of Marjolin's ulcer arising from chronic burn scar are rare. The majority of them are squamous cell carcinoma and basal cell carcinoma. Malignant fibrous histiocytoma is a deep seated pleomorphic sarcoma, which occurs principally as a mass of the extremities, abdominal cavity, or retroperitoneum in adults. Methods: We report a 58-year-old male patient who was admitted due to $3.5{\times}5cm$ chronic ulceration of anterior chest wall on the center of old burn scar. His scar had been occurred by boiling oil and treated with conservative treatment 45 years ago. Preoperative punch biopsy showed suspicious malignant changes and contrast enhanced chest CT showed well-defined, irregular shape enhancing lesion on anterior chest wall without intrathoracic metastasis. Results: The tumor was widely excised and defect was covered with skin graft without infection, necrosis and any other complication. The pathologic findings are compatible with malignant fibrous histiocytoma(storiform - pleomorphic type). The patient underwent 3 cycles of chemotheraphy. Although distant metastasis to the lung developed 6 months later and the patient died 9 month later, there was no local reoccurrence. Conclusion: Aggressive and early excision is needed because malignant fibrous histiocytoma has characteristics of high malignancy with a propensity for early and distant spread. Furthermore, the patient's education about disease entity and postoperative regular follow-up for local recurrence or metastasis is very important. To prevent malignancy from secondly healing burn scar, early skin graft is recommended for patients with deep second degree burn.

• Journal of Veterinary Clinics
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• v.33 no.6
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• pp.362-367
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• 2016

The aim of the study was to evaluate ultrasonographic findings, affected age, hematology, blood chemistry and clinical signs according to open or closed cervix in 102 bitches presented for treatment of pyometra. The prevalence of pyometra according to breed was observed in Maltese 22.5%, Yorkshire Terrier 13.7% and Shih Tzu 12.7%. The mean age of dogs was $9.6{\pm}0.3years$, and open cervix pyometra was more prevalent than closed cervix pyometra. Clinical signs included anorexia, vaginal discharge, depression, polyuria/polydipsia, vomiting, and abdominal distension. The concentration of BUN and the activity of ALP in dogs with closed cervix pyometra were significantly higher than those in dogs with open cervix pyometra (p < 0.05). The white blood cell and neutrophils in dogs with closed cervix pyometra were significant higher than those in dogs with open cervix pyometra (p < 0.05). Ultrasonographic findings of the uterus with open or closed cervix pyometra showed variable patterns. The uterine wall was variable in appearance, from thick and irregular to smooth and thin. The uterine wall was thicker in open cervix pyometra than in closed cervix pyometra. The luminal cavity included smaller amount of anechoic fluid in open cervix pyometra than in closed cervix pyometra.