• Journal of Dental Rehabilitation and Applied Science
• /
• v.25 no.4
• /
• pp.361-374
• /
• 2009

For successful osteogenesis around the implants, interaction between implant surface and surrounding tissue is important. Biomechanical bonding and biochemical bonding are considered to influence the response of adherent cells. But the focus has shifted surface chemistry. The purpose of this study is to evaluate the MC3T3-E1 osteoblast like cell responses of magnesium (Mg) ion implanted titanium surface produced using a plasma source ion implantation method. Commercially pure titanium disc was used as substrates. The discs were prepared to produce four different surface, A: Machine turned surface, B: Mg implanted surface, C: sandblasted surface, D: sandblasted and Mg implanted surface. MC3T3 El osteoblastic like cells were cultured on the disc specimens. Cell adhesion, proliferation, differentiation, and synthesis of extracellular matrix were evaluated. The cell adhesion morphology was evaluated by SEM. RT PCR assay was used for assessment of cell adhesion, proliferation and differentiation. ALP activity was measured for cell differentiation. The results of this study were as follows: 1. SEM showed that cell on Mg ion groups was more proliferative than that of non Mg ion groups. On the machine turned surface, cell showed some degree of contact guidance in aligning with the machining grooves. 2. In RT PCR analysis, osteonectin and c-fos mRNA were more expressed on sandblasted and Mg ion implanted group. 3. ALP activity was not significantly different among all groups. Within the limitations of this study, the following conclusions were drawn: It might indicate Mg ion implanted titanium surface induce better bone response than non Mg ion groups.

• Journal of Life Science
• /
• v.29 no.12
• /
• pp.1337-1344
• /
• 2019

Osteoporosis is characterized by a reduction in bone mass and typically manifests as an increase in fractures. Because this disease is common in elderly populations and lifespans are rapidly increasing, the incidence of osteoporosis has also grown. Most drugs currently used for osteoporosis treatment target osteoclasts in the bone tissue to prevent absorption. However, these medications also cause certain side effects and, furthermore, cannot increase bone mass. Thus, in order to control osteoporosis, regenerative medicine that utilizes adult stem cells and osteoblasts has been extensively studied. Statins, also known as 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors, are cholesterol-lowering drugs that have been widely prescribed for cardiovascular diseases. Interestingly, recent studies have reported the beneficial effects of various statins on bone formation via the activation of osteoblasts. Thus, the current study investigated the effects of seven statin-family drugs on osteoblast activity during osteogenic differentiation using adult stem cells from human periosteal tissue. Specifically, statin effects on alkaline phosphatase activity, an early marker of bone cell differentiation, and on calcium deposit, a late marker of bone cell differentiation, were assessed. The results demonstrate that some statins (for example, pitavastatin and pravastatin) have a weak but positive effect on bone formation, and the findings therefore suggest that statin treatments can be a novel modulator for osteogenic differentiation and regenerative medicine using periosteal stem cells.

• Journal of Life Science
• /
• v.26 no.1
• /
• pp.83-90
• /
• 2016

This study was investigated the improvement effects of Ledebouriella seseloides (LS) ethanol extracts on lipid parameters in an ovariectomized animal model. Sixty, nine-week old female Sprague Dawley rats were randomly assigned to four groups as follows: sham-operated rats (SHAM), ovariectomized rats (OVX-CON) and ovariectomized rats that were treated with LS ethanol extracts (50 mg/kg/day and 200 mg/kg/day, respectively). The diets were fed to the rats for six weeks after their operation. The total-cholesterol and triglyceride contents on serum increased in the OVX-CON group compared to the SHAM group, but supplementation with the LS extract caused these factors to decrease. Notably, the serum LDL-cholesterol concentration in the supplemented 200 mg/kg/day LS ethanol extract group was significantly more reduced than the OVX-CON group. In addition, the platelet aggregation ability was lower in groups treated with LS than in the OVX-CON group. The alkaline phosphatase (ALP) activity was lower in the LS extract group compared to the OVX-CON group. Collagen content, in bone and cartilage, were reduced by ovariectomy, but the supplemented LS extract groups exhibited higher concentrations in their bones. According to these results, the improvement effects of LS extract on serum lipid parameters and osteogenesis in ovariectomized rats were illuminated.

• The korean journal of orthodontics
• /
• v.26 no.2 s.55
• /
• pp.153-162
• /
• 1996

Rapid maxillary expansion is widely used for the correction of anteroposterior discrepancies, constriction of the maxillary arch, etc. This experiment was undertaken to examine the serial changes in the osteogenesis as well as the collagen fiber bundles in the intermaxillary suture during the rapid maxillary expansion treatment. Four young female dogs aged 6 to 8 months old and not showing menarche yet were used for the experiment. The maxillary impression of dogs were taken, expansion device cast and Hyrax screw soldered at the midline in the 1st premolar area. RME device was delivered to the dogs and the activation of 0.25 mm per quarter-turn was done 2 times per day for 10 days until 5 mm separation was made. Separation of the maxilla was confirmed by X-ray. The animals were sacrificed on 0, 15, 30, 60 days from the finish of maxillary separation and preparations for light microscopy and surface electron microscopy were made. The sutures were cut into frontal serial sections for examination of the histological reactions. The following results were obtained and the conclusions made. 1. The edges of the two palatal plates bordering the midpalatal suture which at the beginning of the retention period were mainly composed of compact bone, underwent extensive resorption followed by new bone formation and gradually became spongy bone rich in bone marrow which in the 60 day retention animal became the compact bone with short intermaxillary suture space. During this transformation, newly formed trabecular bone tissues were added to the original margin. 2. Throughout the expansion period, the collagen fibers underwent successive changes such as stretching, loss of polarity, and finally fibrillogenesis. Towards the end of the expansion procedure, sharpey's fiber formation in newly formed bones were observed. 3. Bony spicules were found in the initial stage of retention on occlusal topographic X-rays, which later were confirmed to have ossified. 4. Judging from the histological changes occuring during the experimental expansion, excessive expansion will cause an excessive bleeding, and retard the remodeling of intermaxillary suture. According to the above results, the bone remodeling after rapid maxillary expansion was preceded by the migration of migratory cells into the intermaxillary suture area. The bone remodeling phenomena were on-going during the 2 months retention sample.

• Journal of Periodontal and Implant Science
• /
• v.30 no.4
• /
• pp.851-870
• /
• 2000

The major goals of periodontal therapy is the functional regeneration of periodontal supporting structures already destructed by periodontal disease as well as the reduction of signs and symptoms of progressive periodontal disease. There have been many efforts to develop materials and therapeutic methods to promote periodontal wound healing. There have been increasing interest on the chitosan made by chitin. Chitin is second only to cellulose as the most abundant natural biopolymer. It is a structural component of the exoskeleton of invertebrates(e.g., shrimp, crabs, lobsters), of the cell wall of fungi, and of the cuticle of insects. Chitosan is a derivative of chitin made by deacetylation of side chains. Many experiments using chitosan in various animal models have proven its beneficial effects. The aim of this study is to evaluate the osteogenesis of chitosan on the calvarial critical size defect in Sprague Dawley rats. An 8 mm surgical defect was produced with a trephine bur in the area of the midsagittal suture. The rats were divided into two groups: Untreated control group versus experimental group with 50mg of soluble chitosan gel. The animals were sacrificed at 2, 4 and 8 weeks after surgical procedure. The specimens were examined by histologic, histomorphometric and radiodensitometric analyses. The results are as follows: 1. The length of newly formed bone in the defects was $102.91{\pm}25.46{\mu}m$, $219.46{\pm}97.81{\mu}m$ at the 2 weeks, $130.95{\pm}39.24{\mu}m$, $212.39{\pm}89.22{\mu}m$ at the 4 weeks, $181.53{\pm}76.35{\mu}m$ and $257.12{\pm}51.22{\mu}m$ at the 8 weeks in the control group and experimental group respectively. At all periods, the means of experimental group was greater than those of control group. But, there was no statistically significant difference between the two groups. 2. The area of newly formed bone in the defects was $2962.06{\pm}1284.48{\mu}m^2$, $5194.88{\pm}1247.88{\mu}m^2$ at the 2 weeks, $5103.25{\pm}1375.88{\mu}m^2$, $7751.43{\pm}2228.20{\mu}m^2$ at the 4 weeks and $8046.20{\pm}818.99{\mu}m^2$, $15578.57{\pm}5606.55{\mu}m^2$ at the 8 weeks in the control group and experimental group respectively. At all periods, the means of experimental group was greater than those of control group. The experimental group showed statistically significant difference to the control group at the 2 and 8 weeks. 3. The density of newly formed bone in the defects was $14.26{\pm}6.33%$, $27.91{\pm}6.65%$ at the 2 weeks, $20.06{\pm}9.07%$, $27.86{\pm}8.20%$ at the 4 weeks and $22.99{\pm}3.76%$, $32.17{\pm}6.38%$ at the 8 weeks in the control group and experimental group respectively. At all periods, the means of experimental group was greater than those of control group. The experimental group showed statistically significant difference to the control group at the 2 and 8 weeks. These results suggest that the use of chitosan on the calvarial defects in rats has significant effect on the regeneration of bone tissue in itself

• Journal of Periodontal and Implant Science
• /
• v.35 no.4
• /
• pp.1019-1037
• /
• 2005

The major goals of periodontal therapy are the functional regeneration of periodontal supporting structures already destructed by periodontal disease as well as the reduction of signs and symptoms of progressive periodontal disease. There have been many efforts to develop materials and therapeutic methods to promote periodontal wound healing. There have been increasing interest on the chitosan made by chtin. Chitosan is a derivative of chitin made by deacetylation of side chains. Chitosan has been widely studied as bone substitution and membrane material in periodontology. Many experiments using chitosan in various animal models have proven its beneficial effects. Tetracycline has been considered for use in the treatment of chronic periodontal disease and gingivitis. The aim of this study is to evlauate the osteogenesis of tetracycline blended chitosan membranes on the calvarial critical size defect in Sprague Dawley rats. An 8mm surgical defect was produced with a trephine bur in the area of the midsagittal suture. The rats were divided into five groups: Untreated control group versus four experimental group. Four types of membranes were made and comparative study was been done. Two types of non-woven membranes were made by immersing non-woven chitosan into either the tetracycline solution or chitosan-tetracycline solution. Other two types of sponge membranes were fabricated by immersing chitosan sponge into the tetracycline solution, and subsequent freeze-drying. The animals were sacrificed at 2 and 8 weeks after surgical procedure. The specimens were examined by histologic analyses. The results are as follows: 1. Clinically the use of tetracycline blended chitosan membrane showed great healing capacity. 2. The new bone formations of all the experimental group, non-woven and sponge type membranes were greater than those of control group. But, there was no significant difference between the experimental groups. 3. Resorption of chitosan membranes were not shown in any groups at 2 weeks and 8 weeks. These results suggest that the use of tetracycline blended chitosan membrane on the calvarial defects in rats has significant effect on the regeneration of bone tissue in itself. And it implicate that tetracycline blended chitosan membrane might be useful for guided tissue regeneration.

• Journal of radiological science and technology
• /
• v.40 no.4
• /
• pp.581-587
• /
• 2017

This study was based on the data of total mineral content of about 99% at the age of 16-26 years, we aimed at female university students who are important for bone formation in their early 20s. The purpose of this study was to investigate factors of eating habits affecting their bone density and to provide data to prevent osteoporosis which might occur in the future. It was conducted on 100 female university students in their 20s, the bone mineral density according to BMI was measured by DEAX, and the analysis of 10 eating habits items and the results of BMD measurement on their own results in Excel 2010. As a result, the height was $161.08{\pm}4.70cm$, the weight was $52.43{\pm}6.43kg$, and the BMI was $20.22{\pm}2.48$, which correlated with BMD (p<0.05). According to the BMI classification, 20 had low weight and 80 had normal weight, and BMD was $0.20{\pm}0.41$ at normal weight. In the same sex, the mean T-score of the young adult group was $-0.04{\pm}0.99$ compared with the BMD of the young adult group, and the mean Z-score of the same age group was $0.02{\pm}0.93$ (p<0.001). Eating habits affecting bone mineral density were significantly affected by 3 meals per day, 1-3 cups of coffee per day and p<0.05 for Low salt formula intake. 6-9 dairy product intake was also p<0.05 but not significant. Therefore, it is considered that when 20s female students become middle-aged woman, they should have proper eating habits so that osteogenesis can be improved at young age in order to prevent bone disease.

• Journal of the Korean Orthopaedic Association
• /
• v.54 no.1
• /
• pp.1-8
• /
• 2019

Globally, the elderly population is increasing rapidly, which means that the number of deformity correction operations for elderly spine deformity patient has increased. On the other hand, for aged patients with deformity correction operation, preoperative considerations to reduce the complications and predict a good clinical outcome are not completely understood. First, medical comorbidity needs to be evaluated preoperatively with the Cumulative Illness Rating Scale for Geriatrics or the Charlson Comorbidity Index scores. Medical comorbidities are associated with the postoperative complication rate. Managing these comorbidities preoperatively decreases the complications after a spine deformity correction operation. Second, bone densitometry need to be checked for osteoporosis. Many surgical techniques have been introduced to prevent the complications associated with posterior instrumentation for osteoporosis patients. The preoperative use of an osteogenesis inducing agent - teriparatide was also reported to reduce the complication rate. Third, total body sagittal alignment need to be considered. Many elderly spine deformity patients accompanied degenerative changes and deformities at their lower extremities. In addition, a compensation mechanism induces the deformed posture of the lower extremities. Recently, some authors introduced a parameter including total body sagittal alignment, which can predict the clinical outcome better than previous parameters limited to the spine or pelvis. As a result, total body sagittal alignment needs to be considered for elderly spine deformity patients after a deformity correction operation. In conclusion, for elderly spine deformity patients, medical comorbidities and osteoporosis need to be evaluated and managed preoperatively to reduce the complication rate. In addition, total body sagittal alignment needs to be considered, which is associated with better clinical outcomes than the previous parameters limited to the spine or pelvis.