Antimicrobial Synthetic Bone Grafts

This project aims to produce synthetic bone tissue graft that supports bone regeneration and combats infection simultaneously, according to industry standards and regulations. This original and high value added biomaterial "silver doped calcium phosphate based synthetic bone tissue " will be used in clinical trials in patients with osteomyelitis and implant-related infections for the treatment.

Chronic bone infections are one of the most important problems in orthopedic surgery and are not just a problem of developed societies. When open fracture cases, which may get infected in 1-50%, implant-related infections and diabetic foot ulcer cases are taken into consideration, osteomyelitis will be seen as a very common problem all over the world. Multiple surgeries, long-term use of antibiotics and the high costs affects all societies. The use of synthetic bone grafts is growing faster than the natural bone grafts in the world. USA has spent 246 million US dollars for the use of synthetic bone graft in 2010. For the treatment of bone infections antibiotic impregnated synthetic bone grafts with different characteristics are used. Although these antibiotic impregnated synthetic bone grafts are superior compared to antibiotic bone cement with the implementation of different antibiotics and to be absorbable but they cannot show optimum benefit because the release of antibiotics is not due to host matrix degradation but diffusion control. The other issue to be considered as this regard that the development of microbial resistance to these antibiotics which is also a serious problem. Innovative synthetic bone graft with better contribution of the needs of mechanical properties, depending on the applied bone region, optimized antimicrobial activity and bone tissue regeneration are needed.

In this study, it will be determined whether this silver ion -doped antimicrobial synthetic bone graft that has the capacity to fill the bone voids that may occur in chronic bone infection during disease process or after surgical debridement, also has the capacity to treat the infection in the bone will be used in 12 patients who had been diagnosed as chronic osteomyelitis to see if it cause any unwanted side effect in normal usage conditions and generates unacceptable risks. Clinical, laboratory and radiological investigations will be used to demonstrate the healing of the infections and the cavities in the bone. Blood and urine levels of silver will be detected from patients.

Antimicrobial activity of silver is well-known. The effectiveness of the silver and potential toxicity is related to the dose of silver and application form. In orthopedics, the use of silver is mostly limited to elemental silver coating of metal implants. There is no biotechnologic approach manufactured silver ion -doped calcium phosphate -based synthetic bone graft in the health sector yet. Ionic silver has advantages such as low toxicity, no tolerance of silver against bacteria, and strong antibacterial activity. The trapping of silver ions in the calcium phosphate based ceramic structure overcomes the other systems with its controlled release and its ability to be effective at minimum doses. The project is an original work since it will contribute to bone regeneration while at the same time removing the infection.