• Clinical Pain
• /
• 제15권2호
• /
• pp.92-96
• /
• 2016

Objective: High frequency wave has been used in cancer treatment and cosmetic area but not in musculoskeletal pain yet. The purpose of this study is to evaluate temperature distribution according to depth and confirm safety of high frequency wave through animal study. Method: High frequency wave was applied to the posterior limb of 9 Sprague-Dawley rats for 20 minutes (experimental group) and no wave was used in the same number of rats for control group. Tissue temperature was measured from skin surface to 1 cm depth (surface, 1 mm, 5 mm, and 1 cm) for 5 seconds. Results: In the experimental group, temperature was elevated 3.2℃ at skin surface, 2.87℃ at 1 mm, 2.25℃ in 5 mm, and 1.74℃ in 1 cm depth. These were significantly different from those in the control group (p<0.001). There was no bulla or redness in the skin after high frequency wave stimulation and neither change of myocytes nor collagen degeneration was found in the tissue histology. There was no apoptosis in the skin surface and muscle layer in TUNEL assay. Conclusion: High frequency wave elevated tissue temperature from the skin to muscle layer without both histologic change and apoptosis.

• 대한의용생체공학회:의공학회지
• /
• 제44권1호
• /
• pp.85-91
• /
• 2023

Stress urinary incontinence (SUI) occurs when abdominal pressure increases, such as sneezing, exercising, and laughing. Surgical and non-surgical treatments are the common methods of SUI treatment; however, the conventional treatments still require continuous and invasive treatment. Laser have been used to treat SUI, but excessive temperature increase often causes thermal burn on urethra tissue. Therefore, the optimal conditions must be considered to minimize the thermal damage for the laser treatment. The current study investigated the feasibility of the laser irradiation condition for SUI treatment using non-ablative 980 nm laser from a safety perspective through numerical simulations. COMSOL Multiphysics was used to analyze the numerical simulation model. The Pennes bioheat equation with the Beer's law was used to confirm spatio-temporal temperature distributions, and Arrhenius equation defined the thermal damage caused by the laser-induced heat. Ex vivo porcine urethral tissue was tested to validate the extent of both temperature distribution and thermal damage. The temperature distribution was symmetrical and uniformly observed in the urethra tissue. A muscle layer had a higher temperature (28.3 ℃) than mucosal (23.4 ℃) and submucosal layers (25.5 ℃). MT staining revealed no heat-induced collagen and muscle damage. Both control and treated groups showed the equivalent thickness and area of the urethral mucosal layer. Therefore, the proposed numerical simulation can predict the appropriate irradiation condition (20 W for 15 s) for the SUI treatment with minimal temperature-induced tissue.

• Journal of Periodontal and Implant Science
• /
• 제52권1호
• /
• pp.54-64
• /
• 2022

Purpose: This in vitro study was conducted to evaluate the effects of different debridement techniques and conditioning procedures on root surface morphology and blood clot stabilization. Methods: Two debridement techniques (curette [CU] vs. high-speed ultrasound [US]) and 2 conditioning procedures (ethylenediaminetetraacetic acid [EDTA] and phosphoric acid [PA]) were used for the study. Seven experimental groups were tested on root surfaces: 1) no treatment (C); 2) CU; 3) US; 4) CU+EDTA; 5) US+EDTA; 6) CU+PA; and 7) US+PA. Three specimens per group were observed under scanning electron microscopy (SEM) for surface characterization. Additional root slices received a blood drop, and clot formation was graded according to the blood element adhesion index by a single operator. Data were statistically analyzed, using a threshold of P<0.05 for statistical significance. Results: The C group displayed the most irregular surface among the tested groups with the complete absence of blood traces. The highest frequency of blood component adhesion was shown in the CU+EDTA group (P<0.05), while no differences were detected between the CU, US+EDTA, and CU+PA groups (P<0.05), which performed better than the US and US+PA groups (P<0.05). Conclusions: In this SEM analysis, EDTA and conventional manual scaling were the most efficient procedures for enhancing smear layer removal, collagen fiber exposure, and clot stabilization on the root surface. This technique is imperative in periodontal healing and regenerative procedures.

• 치과방사선
• /
• 제17권1호
• /
• pp.51-87
• /
• 1987

The incorporation of ³H-proline by epithelial and connective tissue elements of rat palatal mucosae was studied in order to investigate the relative levels of protein synthesis by the epithelium and underlying connective tissue cells. Following a sixty minutes incorporation of the radioactive tracer in vitro, it was found that the suprabasal cells had most grains per unit area. Furthermore, the grains were more concentrated over the cytoplasm than the nucleus. This was in contrast with the labeling of basal cells which had twice as many grains over the nucleoplasm than that over the cytoplasm. In intermediate cells; i.e., the spinous layer, the number of silver grains per unit area was decreased from that of the suprabasal cells. In areas where desmosomes were more prominent, many grains were in touch with such desmosomes. However, the labeling appeared to be reduced as soon as the cells became flattened. Moreover, the epidermal keratohyalin granules were relatively free of grains. Except for certain intercellular surfaces the keratinized cells were generally free of grains. On the connective tissue side, silver grains were primarily localized over the fibroblasts with occasional grains being found over palatal muscle cells, neural elements and so on. Most grains over collagenous fibers were found in relation to mature collagen fibrils. Thus, protein synthesis in isolated mucosae of the rat palate appeared to take place both in epithelial and connective elements. There were no apparent tissue alterations caused by the in vitro incorporation procedure utilized under conditions of this study.

• Journal of Trauma and Injury
• /
• 제25권2호
• /
• pp.63-66
• /
• 2012

Resection of the bowel is necessary for the repair of a ventral hernia after recovery from trauma in some cases. In such instances, polyester or polypropylene meshcannot be used due to the possibility of infection; we had to use biological mesh instead. We report a case in which a traumatic hernia was repaired with Permacol (Covidien, Norwalk, CT, USA). A 42-year-old male patient had been injured by a factory machine seven months prior to admission. At that time, he had abdominal wall injury and small bowel perforation. His abdominal wall had been a defect after operation. A CT scan of the abdomen showed that the left abdominal wall, which is lateral to left rectus abdominis muscle had only one muscle layer, an external oblique muscle, and that a previous abdominal incision had a defect along the entire incision. During the exploration, 10 cm of small bowel was removed due to firm adhesion to the previous surgical scar. Permacol mesh was applied and fixed with transfascial fixations and tacks by using the intraperitoneal onlay mesh technique. There were no complications after the surgery and the patient was discharged without any problems.

• 대한소아치과학회지
• /
• 제10권1호
• /
• pp.25-33
• /
• 1983

With electron microscope, author studied on the pulp structure of human primary tooth in shedding stage. Non-carious human primary molar teeth were selected for this study. Using standard methods, specimens were sectioned and examined by light and electron microscope, The results were as follows; 1. In coronal pulp, odontoblasts were replaced by multinucleated odontoclasts, which contained a large number of mitochondria of varying shape and vacuoles in cytoplasm. Where odontoclasts were in contact with tooth surface, the characteristic ruffled border and clear zone were observed. 2. Fibrous tissue with plentiful collagen fibers and fibroblasts was observed adjacent to the dentin in the pulp. Fibroblast contained a number of mitochondria and well-developed rough-surfaced endoplasmic reticulum. 3. Inflammatory cells were observed in the pulp and active fibroblasts could be seen between inflammatory cells. In many cases, cervical epithelium proliferated toward absorbed area. 4. Inflammatory cells consisted of a number of lymphocytes, polymorphonuclear leukocytes, plasma cells and macrophages. Macrophage containing lysosomes in digestive state or phagocyting PMN could be seen. 5. In the primary molar of delayed root resorption, odontoblast layer, zone of Weil and cell-rich zone could be seen at roof of pulp chamber and odontoblast in this area cont과ained some lipid droplets.

• Journal of Pharmaceutical Investigation
• /
• 제40권1호
• /
• pp.45-49
• /
• 2010

Unlike human, with some exceptions, animals do not heal with excessive scar. The lack of suitable animal model has hindered the development of effective scar therapy. We previously reported that partial thickness rabbit ear wound model resembles human wound heal process. This study was designed to prepare a hypertropic scar wound model which can be employed for testing anti-scar therapy. Four wounds were created down to the bare cartilage on the anterior side of each rabbit ear using 8-mm dermal biopsy punch and histology analysis at post operation day (POD) 5, 28 and 48 were performed. As the outcome of scar formation is largely determined by the early inflammatory response to the wounding and the degree and the duration of occlusion, cephalodin(50 mg/kg) was injected daily and medical occlusive dressings were applied. Five micro wound and scar sections were stained with hematoxylin and eosin for quantification of epidermal regeneration and scar hypertrophy. Sections were also stained using Masson's trichrome and Sirius red to evaluate collagen organization and rete ridge formation. Wound closure process was assessed to 7wks post wounding. Complete removal of the epidermis, dermis and perichondrial layer caused delayed epithelialization, which results in hypertropic scarring. The inability of the wounds to contract and the delay in epithelialization in rabbit ear was likely due to cartilage and it created scar elevation. The results suggest that full thickness surgical punch wound model in rabbit ear could be employed as a reliable and reproducible scar wound model for testing anti-scar therapy.

• 치과방사선
• /
• 제10권1호
• /
• pp.9-14
• /
• 1980

The author studied on the effects of X-ray irradiation to the development of periodontal ligament in gestation rats. They were irradiated in their abdomen with 100, 200 and 300 rads respectively in one shot irradiation with deep radiation therapy equipment (MAXIMAR 250-Ⅲ), In 7th, 14th, 21th and 28th day after delivery, those new born rats were respectively sacrificed with ether anesthesia and removed of their mandibles. After removal, those mandibles were fixed in 10% neutral buffer formalin, decalcified with 5% trichloroacetic acid for 5 days and embedded with paraffine. Staining was performed with H-E, Van Gieson, Mallory azan, Bielshowsky-Gomori silver stain and Halmi's oxytalan fiber stain. The results were as follows: 1. Before tooth eruption, all the fiber: components in dental sac were almost always oriented near the outer enamel epithelial \layer. But in irradiated new born rats, those collagen fiber orientation was more irregular than those of control groups, and this phenomenon was more severe in proportion to the amount of irradiation in the gestation period. 2. Before tooth eruption, the connective tissue fibers in periodontal ligament were stained with lighter in the irradiated groups than those of control groups. Oxytalan fibers of irradiated groups were thin and splitting pattern of their fiber morphology to compare with those of control groups. 3. After tooth eruption, the periodontal ligament fibers of irradiated groups were oriented functionally and their morphology was thick, fine and heavy staining. Oxytalan fibers were revealed with oblique parallel arrangement in the periodontal ligament of irradiated groups.

• 대한소아치과학회지
• /
• 제25권3호
• /
• pp.499-505
• /
• 1998

Idiopathic gingival hyperplasia is a rare condition of undetermined etiology. The enlargement is usually associated with the emergence of the teeth into the oral cavity and may regress after extraction. The enlarged gingiva may be primarily attributed to hyperplasia of the subepithelial layer that is relatively avascular and consists of densely arranged collagen bundles and numerous fibroblasts. The recommended time for treatment is after completion of eruption of permanent teeth. But the most important thing is the patient's psychological and esthetic needs. Lately, Schluger has proposed modified gingivectomy procedure with horizontal, internal beveled incision for thinning of the flap resulting in less pain and bleeding after treatment, minimal opportunity of infection. The purpose of this report is to document a case of 8-year-old girl who had registered in Dept. of Pediatric Dentistry of Seoul National University dental hospital for treatment of her gingival hyperplasia and delayed tooth eruption

• 대한두경부종양학회지
• /
• 제39권2호
• /
• pp.7-11
• /
• 2023

Adult fibrosarcoma is a malignant tumor comprising of spindle-shaped fibroblasts with variable collagen production. Due to their aggressive nature and high probability of local tumor recurrence, these tumors require accurate diagnosis and resection according to guidelines. A 57-year-old male presented to the clinic with a complaint of a palpable growing mass in the left scapular area. Examination of the back revealed a 6 cm protruding tumor with a nodular surface. We performed a wide excision, including the infraspinatus fascia layer and subsequent reconstruction using a parascapular island flap. Histopathological analysis demonstrated the typical microscopic features of adult fibrosarcoma. At the 3-year follow-up, there was no evidence of local recurrence and the resection margin was completely clear of tumor.