The use of hydrogels in bone-tissue engineering

Many different types of scaffold materials have been used for tissue engineering applications, and hydrogels form one group of materials that have been used in a wide variety of applications. Hydrogels are hydrophilic polymer networks and they represent an important class of biomaterials in biotechnology and medicine because many hydrogels exhibit excellent biocompatibility with minimal inflammatory responses and tissue damage. Many studies have demonstrated the use of hydrogels in bone-tissue engineering applications. In this report, the summary was conducted on various kinds of polymers and different modification methods of hydrogels to enhance bone formation. The results revealed that hydrogels are applied for bone regeneration and that the modification of hydrogels with bioactive molecules or cell-based approaches resulted in significant increases in new bone formation. This suggests that the use of hydrogels with modification may offer an option for bone-tissue engineering, and further research is needed to identify the biological and physical properties of hydrogels

Clinical Application of Enamel Matrix Derivative for Periodontal Regeneration and Treatment of Peri-Implantitis

One of the goals of periodontal therapy is to regenerate lost supporting structures that have been destroyed by periodontal disease. Treatment procedures including various bone grafts, guided tissue regeneration, use of enamel matrix derivative, or combinations of the aforementioned have been suggested as regenerative periodontal therapies to achieve this goal. Enamel matrix derivative is composed of a number of proteins, 90% of which are amelogenins, and these proteins are thought to induce the formation of periodontal attachment during tooth formation. Previous reports have shown that enamel matrix derivative was able to improve clinical attachment level and reduce probing depth. The results of previous controlled clinical trials have shown that using enamel matrix derivative in combination with bovine porous bone mineral may enhance the regenerative outcome with regard to the clinical attachment level gain compared with using the enamel matrix derivative alone. In this chapter, an extensive review of the role of enamel matrix derivate will be performed using in vitro and in vivo studies. Clinical implications of the enamel matrix derivative will also be discussed

The use of simvastatin in bone regeneration

Simvastatin is a chemical modification of lovastatin, a rate-limiting enzyme of the cholesterol synthesis pathway.Simvastatin has been reported to promote osteoblastic activity and inhibit osteoclastic activity. It is also reported to have an anti-inflammatory effect that works by decreasing the production of interleukin-6 and interleukin-8.The successful use of simvastatin to promote bone formation in vivo depends on the local concentration, and there have been continuous efforts to find an appropriate delivery system. Different doses produce different effects and doses should be prescribed with caution considering benefits and risks. There have been many studies demonstrating the bone-promoting effect of local application with different carriers in various animal models. Simvastatin is shown to increase cancellous bone volume, bone formation rate, and cancellous bone compressive strength.In this review, the summary was made of the various in vitro and in vivo studies. The effects of simvastatins based on different methods of administration, dosage and carriers were also described

Treatment of peri‐implantitis with deproteinised bovine bone and tetracycline: a case report

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91317/1/j.1741-2358.2011.00470.x.pd

Replacing a failed implant adjacent to the implant‐supported restoration in the anterior region after ridge augmentation procedure

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87147/1/j.1741-2358.2009.00361.x.pd

Anomalous response in the vicinity of spontaneous symmetry breaking

We propose a mechanism to induce negative AC permittivity in the vicinity of a ferroelectric phase transition involved with spontaneous symmetry breaking. This mechanism makes use of responses at low frequency, yielding a high gain and a large phase delay, when the system jumps over the free-energy barrier with the aid of external fields. We illustrate the mechanism by analytically studying spin models with the Glauber-typed dynamics under periodic perturbations. Then, we show that the scenario is supported by numerical simulations of mean-field as well as two-dimensional spin systems.Comment: 6 pages, 5 figure

Distribution of Korean Family Names

The family name distribution in Korea is investigated in comparison with previous studies in other countries. In Korea, both the family name and its birthplace, where the ancestor of the family originated, are commonly used to distinguish one family name from the others. The family name distributions with and without the information of the regional origins are analyzed by using different data sets of various sizes, and compared with previous studies performed in other countries. The growth rate of the family is empirically obtained. Contrary to commonly used assumptions, the growth rate is found to be higher for the smaller family.Comment: 13 pages in one column forma