View clinical trials related to Tissue Engineering.
Filter by:A wide range of resorbable and non-resorbable membranes have been investigated over the last decades. Barrier membranes protect bone defects from ingrowth of soft tissue cells, provide mechanical stability of the defect area and allow bone progenitor cells to develop within a blood clot that is formed beneath the barrier membrane, taking a minimum of four to six weeks for periodontal tissues and 16-24 weeks for bone1,2.These membranes are utilized to reconstruct bone defects prior to implantation and to cover dehiscences and fenestrations around dental implants. When aiming to regenerate bone, resorbable or a non - resorbable membranes should be selected depending on location, size and defect area. However, until now the ideal membrane has not been described due to different opinions between authors3,4. Nevertheless, an ideal membrane should maintain its barrier function enough time for new bone formation, and if possible should be resorbable, so that a second surgical procedure for the explantation of the membrane would not be required, thus reducing the morbidity5. However, the use of a barrier membrane is a technique-sensitive procedure that is not free of complications. The main cause of Guided Bone Regeneration (GBR) failure is related to early or late exposure of the membrane, leading to contamination and infection of the biomaterial, irreversibly compromising bone regeneration4,6,7. Consequently, the inflammatory reaction of the surrounding soft tissues may require early removal of the membrane. Other complications, such as the onset of an abscess with purulent exudate, can also lead to a complete failure of GBR even without exposure of the membrane. It is thought necessary to perform this clinical study due to the lack of information present in the literature about the different types of membranes that exist nowadays, how they act in the human body with or without performing some type of regeneration and how our body acts towards them.
This study is to try to maintain cultured dermal papilla cells in spherical structure in vitro before transplanting into dermis in vivo. Also, this study is aimed in clarifying actual mechanism of inducing hair follicle by dermal papilla cells.
This study will determine if bone marrow stromal cells can be used as a graft for regeneration of bony defects. These cells have the ability to form new bone and to support the formation of blood. Stromal cells have been identified in other tissues, such as the dermis (underside of skin), spleen, thymus and fat, but it is not known whether these cells can make bone and support blood formation as well as bone marrow stromal cells. Patients undergoing surgery at Suburban Hospital in Bethesda, Maryland, in which some of the bone, dermis, spleen, thymus or fat tissue is removed may be eligible for this study. For this study, a small piece of the tissue that is removed during surgery for examination by a pathologist will be used for research. Stromal cells from the specimen will be collected and grown in the laboratory. The genes and proteins in the different cell types will be compared, and the ability of stromal cells from the different tissues to make bone and to support the formation of blood will be studied.