PURPOSE: It has been suggested that primary implant stability plays an essential role in successful osseointegration. Resonance frequency analysis (RFA) is widely used to measure the initial stability of implants because it provides superior reproducibility and non-invasiveness. The purpose of this study is to investigate whether the fractal dimension from the panoramic radiograph is related to the primary stability of the implant as represented by RFA. METHODS: This study included 22 patients who underwent dental implant installation at the Department of Periodontology of Seoul National University Dental Hospital. Morphometric analysis and fractal analysis of the bone trabecular pattern were performed using panoramic radiographs, and the implant stability quotient (ISQ) values were measured after implant installation using RFA. The radiographs of 52 implant sites were analyzed, and the ISQ values were compared with the results from the morphometric analysis and fractal analysis. RESULTS: The Pearson correlation showed a linear correlation between the ISQ values of RFA and the parameters of morphometric analysis but not of statistical significance. The fractal dimension had a linear correlation that was statistically significant. The correlation was more pronounced in the mandible. CONCLUSIONS: In conclusion, we suggest that the fractal dimension acquired from the panoramic radiograph may be a useful predictor of the initial stability of dental implants.
Dental Implantation ; Dental Implants ; Fractals ; Humans ; Mandible ; Osseointegration ; Radiography, Panoramic

PURPOSE: The aim of this study was to evaluate the stemness of cells from canine dental tissues and bone marrow. METHODS:Canine periodontal ligament stem cells (PDLSC), alveolar bone stem cells (ABSC) and bone marrow stem cells(BMSC) were isolated and cultured. Cell differentiations (osteogenic, adipogenic and chondrogenic) and surface antigens (CD146, STRO-1, CD44, CD90, CD45, CD34) were evaluated in vitro. The cells were transplanted into the subcutaneous space of nude mice to assess capacity for ectopic bone formation at 8 weeks after implantation. RESULTS: PDLSC, ABSC and BMSC differentiated into osteoblasts, adipocytes and chondrocytes under defined condition. The cells expressed the mesenchymal stem cell markers differently. When transplanted into athymic nude mice, these three kinds of cells with hydroxyapatite /beta tricalcium phosphate (HA/TCP) carrier showed ectopic bone formation. CONCLUSIONS: This study demonstrated that canine dental stem cells have stemness like bone marrow stem cells. Transplantation of these cells might be used as a therapeutic approach for dental stem cell-mediated periodontal tissue regeneration.
Adipocytes ; Animals ; Antigens, Surface ; Bone Marrow ; Calcium Phosphates ; Cell Differentiation ; Chondrocytes ; Durapatite ; Mesenchymal Stromal Cells ; Mice ; Mice, Nude ; Osteoblasts ; Osteogenesis ; Periodontal Ligament ; Regeneration ; Stem Cells ; Transplants

PURPOSE: The aim of this study was to compare the effectiveness of hydroxyapatite containing toothpaste with positive control toothpastes in reducing dentine hypersensitivity. MATERIALS AND METHODS: This clinical trial was a double-blind, randomized, parallel group comparison of two, namely hydroxyapatite containing toothpaste and strontium chloride containing toothpaste. A total of 55 subjects were included in this study. The subjects were given randomly assigned one of the two toothpastes after received tooth brushing instruction at baseline. Some clinical indices(PI, GI, PD), verbal rating score(VRS) for sensitivity to stimulus, the effect in relieving sensitivity and visual analogue scale(VAS) for sensitivity at baseline, week 2, week 4 and week 8 were assessed. All data were evaluated by intention-to-treat analysis. RESULTS: Overall, PI and GI scores were significantly reduced compare baseline in all groups(p<0.05). In addition, there was significant difference in PI at 4 weeks and in GI at 4, 8 weeks between groups. The proportions of subjects relieved sensitivity were 70.4% in experimental group and 57.1% in control group at 8 weeks respectively. The VRS for sensitivity to three kinds of stimuli and VAS for sensitivity decreased according to time, there was no overall difference between two groups(p>0.05). CONCLUSION: This study demonstrated that the new hydroxyapatite containing toothpaste was similarly effective in reducing dentine hypersensitivity with pre-existing benchmark toothpaste.
Dentin ; Dentin Sensitivity ; Durapatite ; Strontium ; Tooth ; Toothpastes

PURPOSE: Gene therapy (ex vivo) has recently been used as a means of delivering bone morphogenetic proteins (BMPs) to sites of tissue regeneration. In the present study, we investigated the effect of co-transduction of adenoviruses expressing BMP-2 and BMP-7 on osteogenesisof C2C12 cells in vitro. METHODS: A replication-defective human adenovirus 5 (Ad5) containing a cDNA for BMPs in the E1 region of the virus (Ad5BMP-2 and Ad5BMP-7) was constructed by in vivo homologous recombination. Functional activity of Ad5BMP-2 and Ad5BMP-7 were evaluated in mouse stromal cells (W20-17cells). C2C12 cells are transduced with various MOI (multiplicity of infection) of Ad5BMP-2 and Ad5BMP-7 to assess most effective and stable titer. Based on this result, C2C12 cells were transduced with Ad5BMP-2 and Ad5BMP-7 alone or by combination. BMPs expression, alkaline phosphatase (ALPase) activity, cell proliferation, and mineralization were assessed. RESULTS: Ad5BMP-2 and Ad5BMP-7 are successfully transduced to W20-17 cells, and secreted BMPs stimulated cell differentiation. Also, C2C12 cells transduced with Ad5BMPs showed expression of BMPs and increased ALPaseactivity. In all groups, cell proliferation was observed over times. At 7days, cells co-transduced with Ad5BMP-2 and Ad5BMP-7 showed lower proliferation than the others. C2C12 cells co-transduced with Ad5BMP-2 and Ad5BMP-7 had greater ALPaseactivity than that would be predicted if effect of individual Ad5BMPs were additive. Little mineralized nodule formation was detected in cells transduced with individual Ad5BMPs. In contrast, Ad5BMP-2 and Ad5BMP-7 combination stimulated mineralization after culturing for 10 days in mineralizing medium. CONCLUSIONS: Present study demonstrated that adenoviruses expressing BMPs gene successfully produced BMPs protein and these BMPs stimulated cells to be differentiated into osteoblastic cells. In addition, the osteogenic activity of Ad5BMPs can be synergistically increased by co-transduction of cells with Ad5BMP-2 and Ad5BMP-7.
Adenoviridae ; Adenoviruses, Human ; Alkaline Phosphatase ; Animals ; Bone Morphogenetic Protein 2 ; Bone Morphogenetic Protein 7 ; Bone Morphogenetic Proteins ; Cell Differentiation ; Cell Proliferation ; DNA, Complementary ; Durapatite ; Genetic Therapy ; Homologous Recombination ; Mice ; Osteoblasts ; Osteogenesis ; Regeneration ; Stromal Cells ; Viruses

PURPOSE: This study was performed to evaluate the effect of powered toothbrush with a wireless remote display on the subjective and objective oral hygiene improvement. METHODS: One hundred and fifteen subjects in healthy or mild gingivitis status between the ages of 20 and 90 were recruited and reviewed for study inclusion criteria. At first visit, 115 pre-screened subjects filled in the questionnaire form which consisted of demographic factors, behavioral factors (smoking, alcohol consumption), toothbrushing habits (brushing time and frequency), self-reported oral health status, and self-satisfaction. Baseline clinical indices (Plaque index, Gingival index) were also recorded by a periodontist. Subjects were instructed how to use powered toothbrush with a wireless remote display, and were provided with it. Thirty days after first visit, 90 subjects returned for the second assessment by self-reported questionnaire form and professional clinical checkup. Statistical analysis was performed using paired t-test for the difference between baseline and second visit data. The relationship among variables was examined with chi-square test and Fisher's exact test. RESULTS: Significant differences were not found on self-reported satisfaction related with sex, smoking, alcohol consumption (P<0.05). Self-reported tooth brushing habit was improved in the aspect of brushing time and frequency. Significant differences were found on the self-reported oral health status, self-satisfaction, and clinical indices between the baseline and second visit data (P<0.01). Clinical indices were significantly reduced after using powered toothbrush with a wireless remote display (P<0.01). No adverse reactions were reported during the study period. CONCLUSIONS: Powered toothbrush with a wireless remote display successfully promoted oral hygiene from the subjective and objective viewpoint after 30 days of home usage.
Alcohol Drinking ; Demography ; Gingivitis ; Oral Health ; Oral Hygiene ; Periodontal Index ; Personal Satisfaction ; Surveys and Questionnaires ; Smoke ; Smoking ; Tooth ; Toothbrushing

Different kinds of forces can be applied to the biological tissue. The analysis of the applied force is highly important to explain the mechanism of cellular response. In this study, the applied force to the collagen gel was analyzed by the finite elements analysis. The model received two different kinds of static force (compression and tension). The force range was 50g to 400g. In results, von Mises stress was concentrated in the peripheral region in the compression model. It was concentrated in the central area in the tension model. However, the compressive force was high in the peripheral area of the compression model and the tensional force was also high in the same area of the tension model. In conclusion, the applied force could be different to the region and it should be considered in the experiment to analyze the effects of the mechanical force on the cells.
Cell Culture Techniques ; Collagen ; Finite Element Analysis

Different kinds of forces can be applied to the biological tissue. The analysis of the applied force is highly important to explain the mechanism of cellular response. In this study, the applied force to the collagen gel was analyzed by the finite elements analysis. The model received two different kinds of static force (compression and tension). The force range was 50g to 400g. In results, von Mises stress was concentrated in the peripheral region in the compression model. It was concentrated in the central area in the tension model. However, the compressive force was high in the peripheral area of the compression model and the tensional force was also high in the same area of the tension model. In conclusion, the applied force could be different to the region and it should be considered in the experiment to analyze the effects of the mechanical force on the cells.
Cell Culture Techniques ; Collagen ; Finite Element Analysis

No abstract available.

Accidental intrathecal vincristine instillation is extremely toxic to the central nervous system. If given intrathecally, it produces a rapidly ascending, usually fatal, neuromyeloencephalopathy. This is a case where a 10-year-old girl received an inadvertent intrathecal administration of vincristine. The clinical course was rapidly progressive and resulted in comatose and vegetative state. Magnetic resornance image at post-injection 11 day showed high signal intensity lesion in cerebellar hemisphere and vermis adjacent to CSF passage third and fourth ventricle on T2 weighted images.
Central Nervous System ; Child ; Coma ; Female ; Fourth Ventricle ; Humans ; Persistent Vegetative State ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Vincristine*

Perinatal transmission and infection of hepatitis B virus (HBV) in early childhood were observed in the offsprings of hepatitis B surface antigen (HBsAg)-positive mothers who had been vaccinated against HBV immediately after giving birth. This prophylaxis failure of perinatal HBV infection is likely due to the interplay of the virus and host immune response. To investigate whether the HLA polymorphism affected the outcome of the perinatal prophylaxis, HLA class I (HLA-A, B and Cw) and class II (HLA-DRB1, DQA1, DQB1 and DPB1) were typed using serology, PCR-SSOP (polymerase chain reaction-sequence specific oligonucleotide probe), and PCR-ARMS (amplification refractory modification system) methods in 22 HBeAg-positive mothers and their 10 prophylaxis-succeeded and 12 prophylaxis- failed children. The HLA types of the mothers and their children were compared with 198 HBsAg-negative healthy controls in a Korean population. HLA-B35 (relative risk=4.2, p<0.01), B51 (relative risk=3.2, p<0.02), DRB1*07 (relative risk=3.8, p<0.03), and DQA1*02 (relative risk=3.8, p<0.03) alleles were more frequent in HBeAg-positive mothers than in the controls. Also, HLA-DRB1*13 (relative risk=0.1, p<0.02) and DPB1*0401 (relative risk=0.1, p<0.02) alleles were less frequent in HBeAg-positive mothers. However, HLA alleles did not affect the outcome of the perinatal prophylaxis against HBV. These results suggest that the reported influences of some HLA alleles on the natural chronic HBV infections may not operate in the HBV infections in children received perinatal prophylaxis.
Alleles* ; Child ; Hepatitis B Surface Antigens ; Hepatitis B virus* ; Hepatitis B* ; Hepatitis* ; HLA-B35 Antigen ; Humans ; Mothers ; Parturition