behzad hooshmand

The use of bone scaffolds is one of the new and efficient techniques for repairing bone defects that provide a suitable platform for cell proliferation and growth to repair the target tissue. One of the most important causes of failure of transplants and surgical procedures is the invasion of bacteria at the site of the complication and the development of severe infection. The purpose of this study, which was carried out at the Faculty of New Sciences and Technologies, University of Tehran at 2017-2019, Antibacterial Properties of Porous Scaffolds Made of Gelatin, Calcium Phosphate Zeolite with Loading of Clindamycin.

In this study, freeze-drying was made from a combination of gelatin, calcium phosphate, and natural zeolite of bone tissue scaffolds and then the drug was loaded with different amounts of clindamycin. The surface of the scaffold was examined by scanning electron microscopy and antibacterial test and drug release test were performed on the scaffold.

The results showed that the aforementioned composite scaffold did not induce growth inhibition in the antibacterial test, However, after loading the drug on the scaffold with a concentration of 0.01 drug, the growth zone was 2 and 4 mm in diameter for Escherichia coli and Staphylococcus aureus, respectively.

Addition of the antibacterial agent clindamycin to the bone scaffold made a suitable substrate for drug delivery to bone tissue at the site of removal has been removed to prevent the growth of infection at the scaffold implant during the first period of repair.

Due to the composite structure of the jaw bone, gelatin and beta-calcium phosphate (b-TCP) biomaterials have been used repeatedly in bone tissue engineering. Despite the desirable properties of scaffolds made, their application has been limited due to their poor mechanical properties and high degradability. The aim of this study was to investigate the effect of clinoptilolite biomaterial with unique mechanical properties such as remarkable mechanical properties, low degradation rate and highly favorable biocompatibility properties in gelatin and b-TCP scaffolds.

Preparation of porous scaffold as a template was made leading to freeze drying method using weight percent of 50 for gelatin, 25 b-TCP and 25 Clinoptilolite. SEM analysis and image j software was used in order to evaluation of scaffold surface and finding of porosity frequency. Finally, compressive strength of scaffold was evaluated. 

In clinoptilolite / b-TCP / Gelatin scaffolds, porosity up to 250 nanometers was recorded which was the best for angiogenesis. In addition to gelatin, clinoptilolite also had a positive effect on porosity. Using compressive strength analysis, increasing of Youngchr('39')s modulus was also observed from 100 to 166 mega Pascal by that Clinoptilolite is the most effective agent in modifying this modulus.

Considering the results, clinoptilolite that in addition to improving and enhancing the mechanical properties of composite scaffolds, had a significant effect on the increase in the size and porosity of jaw bone tissue engineering scaffolds. According to the obtained characteristics it can be said that the sample presented is in accordance with the properties of extracellular scaffold (ECM) of jaw bone tissue and would be a suitable choice in tissue engineering of this type of bone.

COVID-19 is a viral disease caused by SARS-CoV-2 that quickly became a global pandemic during 2020. Considering the recent outbreak, the lack of adequate data regarding SARS-CoV-2, and consequently the risk of dental practice and potential cross-infection, this article attempted to address the information collected so far in accordance with the internationally valid guidelines and to suggest a relatively safe protocol for the management of o patients. In other words, this study describes the essentials that need to be considered for the dental office reopening.