• Journal of Oral Medicine and Pain
• /
• v.34 no.2
• /
• pp.197-205
• /
• 2009

The purpose of this study was to investigate the treatment pattern of patients with neuropathic pain (NeP) in Korea through computerized database of Health Insurance Review and Assessment Service (HIRAS) over three years' period from 2003 to 2005. The results showed that the numbers of treatment visits were the highest for diabetic neuropathy (DN), followed by postherpetic neuralgia (PHN) and trigeminal neuralgia (TN) in order. Top 3 specialties for treatment visits due to NeP conditions were neurology, neurosurgery and anesthesiology. While cost of a treatment visit was higher in anesthesiology and emergency clinics compared to other clinics, there was a tendency to increase costs for visits to clinics of rehabilitation medicine and family medicine over the three years. Cost of dental visits was relatively high for TN, atypical facial pain (AFP) and atypical odontalgia (AO). Surgeries frequently applied to patients with NeP were sympathetic plexus or ganglion block, block of peripheral branch of spinal nerve and cranial nerve or its peripheral branch block. Most common prescribed medication were anticonvulsants, anti-inflammatory analgesics and anti-psychotic drugs while anti-inflammatory analgesics were overwhelmingly frequently prescribed for AO and glossodynia. Based on the results of this study, NeP disorders more relevant to dentists were AO, TN and AFP, TN of which seems to be the most important in terms of patients' number and cost for treatment visits. This indicates that dentists, especially oral medicine specialists should actively participate in management of TN, AO and AFP and share relevant information with patients and community.

• The Journal of Korean Academy of Prosthodontics
• /
• v.57 no.4
• /
• pp.342-349
• /
• 2019

Purpose: The purpose of this study was to retrospectively investigate the survival and success rate of implant-supported fixed prosthesis according to the materials in the posterior area. Other purposes were to observe the complications and evaluate the factors affecting failure. Materials and methods: Patients who had been restored implant prosthesis in the posterior area by the same prosthodontist in the department of prosthodontics, dental hospital, Chonbuk National University, in the period from January 2011 to June 2018 were selected for the study. The patient's sex, age, material, location, type of prosthesis and complications were examined using medical records. The KaplanMeier method was used to analyze the survival and success rate. The Log-rank test was conducted to compare the differences between the groups. Cox proportional hazards model was used to assess the association between potential risk factors and success rate. Results: A total of 364 implants were observed in 245 patients, with an average follow-up of 17.1 months. A total of 5 implant prostheses failed and were removed, and the 3 and 5 year cumulative survival rate of all implant prostheses were 97.5 and 91.0, respectively. The 3 and 5 year cumulative success rate of all implant prostheses were 61.1% and 32.9%, respectively. Material, sex, age, location and type of prosthesis did not affect success rate (P>.05). Complications occurred in the order of proximal contact loss (53 cases), retention loss (17 cases), peri-implant mucositis (12 cases), infraocclusion (4 cases) and so on. Conclusion: Considering a high cumulative survival rate of implant-supported fixed prostheses, regardless of the materials, implant restored in posterior area can be considered as a reliable treatment to tooth replacement. However, regular inspections and, if necessary, repairs and adjustments are very important because of the frequent occurrence of complications.

• The Journal of Korean Academy of Prosthodontics
• /
• v.59 no.3
• /
• pp.271-280
• /
• 2021

Purpose. The aim of this study was to evaluate the relationship between the patient's occlusion and a cracked tooth by using T-scan occlusal analysis and a quantitative light-induced fluorescence (QLF) technology. Materials and methods. This study was carried out on 51 patients having cracked teeth between January, 2019 and December, 2020. The tooth crack was determined with a Q-ray pen and QLF parameters (ΔF_max and ΔR_max) were obtained by a Q-ray software. T-scan tests were conducted to all subjects and then, the occlusal force and disclosing time were analyzed. Mann-Whitney U test was performed to compare the occlusal force and disclosing time between cracked teeth groups and contra-lateral normal teeth groups (α = .05). Mann-Whitney U test was performed to compare ΔF_max and ΔR_max according to the results of cold/bite tests (α = .05). A Spearman correlation analysis was run to determine the relationship between ΔF_max or ΔR_max and occlusal force or disclosing time (α=.05). Results. The mean occlusal force and disclosing time were significantly higher on cracked teeth than on normal teeth (P < .05). The ΔF_max or ΔR_max were not significantly different according to the results of cold/bite tests (P > .05). There was no correlation between ΔF_max or ΔR_max and occlusal force or disclosing time (P > .05). Conclusion. There was a significant relationship between occlusion and cracked tooth syndrome. QLF has the potential to be a valuable tool for the diagnosis of tooth crack in clinical practice.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.48 no.1
• /
• pp.77-94
• /
• 2021

The purpose of this study was to investigate the three-dimensional characteristics of mesiodens using Cone-beam Computed Tomography(CBCT) and analyze the factors affecting complications and anesthetic methods of extraction. This study evaluated 602 mesiodens of 452 patients who underwent extraction of mesiodens at the department of Pediatric Dentistry in Seoul National University Dental Hospital between 2017 and 2019. The ratio of mesiodens patients over total patient per year was gradually increased over the past 20 years. Mesiodens with labio-palatally horizontal direction while root directing labial were the most common among the mesiodens with horizontal direction. Mesiodens were the most common at the cervical side of the adjacent teeth(37.0%) and mesiodens located in the near-palatal side were observed about 3.83 times higher than the far-palatal side. Most of the mesiodens(82.1%) were in contact with adjacent permanent teeth on all three sides of the CBCT and 46.2% of mesiodens had curved roots. The patient's age, vertical position, presence of complications, and proximity showed a significant difference in the selection of general anesthesia among anesthetic methods. The direction and vertical position of mesiodens had a significant effect on complications. These results provide a better understanding of mesiodens for establishing an accurate diagnosis and treatment plan.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.48 no.2
• /
• pp.221-228
• /
• 2021

The aim of this study was to evaluate the use of easily accessible machine learning application to identify mesiodens, and to compare the ability to identify mesiodens between trained model and human. A total of 1604 panoramic images (805 images with mesiodens, 799 images without mesiodens) of patients aged 5 - 7 years were used for this study. The model used for machine learning was Google's teachable machine. Data set 1 was used to train model and to verify the model. Data set 2 was used to compare the ability between the learning model and human group. As a result of data set 1, the average accuracy of the model was 0.82. After testing data set 2, the accuracy of the model was 0.78. From the resident group and the student group, the accuracy was 0.82, 0.69. This study developed a model for identifying mesiodens using panoramic radiographs of children in primary and early mixed dentition. The classification accuracy of the model was lower than that of the resident group. However, the classification accuracy (0.78) was higher than that of dental students (0.69), so it could be used to assist the diagnosis of mesiodens for non-expert students or general dentists.

• Journal of vocational education research
• /
• v.35 no.4
• /
• pp.19-46
• /
• 2016

The purpose of this study is to analyze the curriculum implementation of the Nursing-Specialized Vocational High School by researching on operation, organization and environment of the program of Nursing. This study aims to improve the curriculum of the Nursing-Specialized Vocational High School. This study has analyzed previous existing studies, Link of School info, Educational Statistics and data indicating establishment, operation and curriculum of the department of Nursing which have been collected from web sites of institutions and associations relevant to Nurse Education. The major results of this study are as follows: 1) As of the first semester of the year 2016, out of a total of thirty eight Specialized Vocational High Schools and Meister High Schools in the country, 6.4% of the schools have nursing educational programs. These schools have established the programs under various names, such as Health Nursing, Dental Health Nursing, Nursing, Nursing and Medical Tourism, Accounting in Nursing and Nursing Management, etc. Since 2012, enrollment rates have increased while post-graduation employment rates have decreased, with the average employment rate of Specialized Vocational High School graduates having reached up to 46% by 2015. 2) The Nursing-Specialized Vocational High School aims to create skilled Nurses Assistant such as Nurse Aide and Care giver. The program is successful in providing necessary courses to acquire required certification and proficient field experience but requires revisional changes in order to create a long-term program of sufficient qualification. The official requirement of 780 hours of field practice was completed during the three educational breaks from the first year of high school to the second year, while the curriculum was conducted separately in the field hospitals. 3) An average of two laboratory classrooms were available based on the facility requirement standard of Cities and Provinces Educational Policies. In order to secure proficient instructors of Nursing education, establishment of specific indicated subjects, regional placement, in-service education, research and supervision are essential for establishing excellence and continual improvement.

• Journal of Life Science
• /
• v.29 no.3
• /
• pp.295-302
• /
• 2019

Liquiritigenin (LG) is a chiral flavonoid isolated from the roots of licorice. It exhibits multiple biological activities including anti-oxidant, anti-cancer, and anti-inflammatory effects. In particular though, the anti-cancer activity of LG in oral squamous cell carcinoma has yet to be elucidated, and LG-induced apoptosis in oral squamous cell carcinoma remains poorly understood. In the present study, we tested the role of LG in inducing apoptosis in oral squamous cell carcinoma cells. LG treatment of HN22 cells resulted in a dose-dependent inhibition of cell viability as detected by a 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide assay. The induction of apoptosis in terms of Annexin V/7-Aminoactinomycin D staining, sub-G1 population, and multi-caspase activity were assessed with a $Muse^{TM}$ Cell Analyzer. Flow cytometric analysis revealed that LG treatment resulted in G2/M arrest in cell cycle progression and downregulation of cyclin B1 and CDC2 expression in a concentration-dependent manner. It also resulted in significant upregulation of p27. In addition, LG was seen to trigger the generation of reactive oxygen species and induce CCAAT/enhancer-binding protein homologous protein and 78-kDa glucose-regulated protein in concentration-dependent upregulation. The LG treatment of HN22 cells led to a loss of mitochondrial membrane potential (${\Delta}{\Psi}m$); it also reduced the levels of anti-apoptotic protein and increased the expression of apoptotic protease activating factor-1, cleaved poly (ADP-ribose)polymerase and Bax. Overall, our results indicate that the pro-apoptotic effects of LG in HN22 cells depend on the activation of both intrinsic and extrinsic signaling pathways. Thus, our results suggest that LG constitutes a natural compound with a potential role as an anti-tumor agent in oral squamous cell carcinoma.

• Journal of the Korean Applied Science and Technology
• /
• v.36 no.2
• /
• pp.394-406
• /
• 2019

The cellular senescence may be due to damage by the reactive oxygen species (ROS). This study has compared the antioxidant activity in the human cell lines of various origins, including 10S and 50S-derived normal skin fibroblasts, and 10S bone marrow, dental tissue and adipose-derived adult stem cells. After being exposed to $H_2O_2$, half inhibitory concentration ($IC_{50}$) values by cytotoxicity assay was significantly (P<0.05) lower in 50S-derived skin fibroblasts, than in 10S-derived skin fibroblasts and various adult stem cell lines. The cell population doubling time (PDT) and the cell frequency with high senescence associated-${\beta}$-galactose activity were remarkably increased in 50S-derived fibroblasts exposed to 50 ppm $H_2O_2$ for 7 days, than those of 10S-derived fibroblasts and various adult stem cell lines. Further, the expression level of antioxidant-related genes, glutathione peroxidase (GPX) and catalase (CAT), was investigated in 10S and 50S-derived skin fibroblasts, and 10S-derived various adult stem cells by reverse transcription polymerase chain reaction (RT-PCR). The expression level of GPX was higher in most of cell lines, compared to CAT, and a significantly (P<0.05) higher expression level of GPX was observed in 10S-derived skin fibroblasts and adult stem cell lines, compared to 50S-derived skin fibroblasts. We concluded that old-aged skin fibroblasts seemed to be less resistant against ROS than young-aged skin fibroblasts and adult stem cells.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.35 no.2
• /
• pp.72-80
• /
• 2019

Purpose: The purpose of this study is to compare and analyze the shear bond strength and fracture pattern in different enamel tooth surface treatments for resin splinting materials. Materials and Methods: G-FIX and LightFix were used as tooth splinting materials. Twenty bovine mandibular incisors were used for the preparation of the specimens. The exposed enamel surface was separated into four parts. Each tooth was treated with 37% phosphoric acid, 37% phosphoric acid + adhesive resin, 37% phosphoric acid + G-premio bond, and G-premio bond for each fraction. Shear bond strength was measured using a universal testing machine. After measuring the shear bond strength, the fractured surface of the specimen was magnified with a microscope to observe the fracture pattern. Two-way ANOVA was used to verify the interaction between the material and the surface treatment method. One-way ANOVA was used for comparison between the surface treatment methods of each material and post-hoc test was conducted with Scheffe's test. An independent t-test was conducted to compare shear bond strengths between materials in each surface treatment method. All statistics were conducted at 95% significance level. Results: G-FIX, a tooth splinting resin, showed similar shear bonding strength when additional adhesive resins were used when material was applied after only acid etching, and LightFix showed the highest shear bonding strength when additional adhesive resins were used after the acid etching. In addition, both G-FIX and LightFix showed the lowest shear bond strength when only self-etching adhesive was applied without additional acid etching. Verification of interactions observed interconnection between resins and surface treatment methods. Most of the mixed failure was observed in all counties. Conclusion: When using G-FIX and LightFix, which are tooth-splinting materials, it is considered that sufficient adhesion will be achieved even after applying only acid etching as instructed by the manufacturer.

• Journal of Life Science
• /
• v.29 no.6
• /
• pp.724-734
• /
• 2019

The present study investigated the cytotoxicity of particulate matter (PM) derived from car air filter (outdoor PM) and home cleaner filter (indoor PM) in the various human cell lines. Each outdoor and indoor PM were harvested by ethanol extraction method, subsequently sieved with 10 um filter paper, sterilized with autoclave and added to culture media. The half maximal inhibitory concentration ($IC_{50}$) values was significantly (p<0.05) lower in the outdoor PM, compared with indoor PM, and the significantly (p<0.05) higher $IC_{50}$ values were observed in the cancer cell lines (A-549 lung adenocarcinoma and AGS stomach adenocarcinoma), than those of normal MRC-5 fibroblasts and dental papilla tissue derived-mesenchymal stem cells (DSC). After being exposed to $100{\mu}g/ml$ outdoor PM for 7 days, the population doubling time (PDT) was significantly (p<0.05) increased in especially MRC-5 and DSC cell lines, compared with untreated cell lines. Further, the expression of senescence-associated ${\beta}$-galactosidase activity was up-regulated in all the cells exposed to outdoor PM than those of untreated control. Besides, the expression level of inflammation-associated genes, such as cyclooxygenase-2 (COX-2) and interleukin-6 (IL-6) was found to be significantly (p<0.05) increased in the outdoor PM-treated cell lines than those of untreated cell lines. Our results showed that PM induces the cytotoxicity via arrest of cell growth, cell damage and inflammation response.