<i>In Vitro</i> Characterization of Polyurethane-Carbon Nanotube Drug Eluting Composite Scaffold for Dental Tissue Engineering Application

Tooth loss due to periodontal disease, dental caries, trauma or a variety of genetic disorders causes an adverse inability in adult’s lives. It is proved that biodegradable composite scaffolds in dental tissue engineering could play crucial role. To inhibit bacterial colonization in dental structure noticeable research concerning the drug delivery approach has been administrated. Nanostructures retain and release drug molecules more efficiently and continuously than other microstructure. In the present research, composite electrospun nanofibers of polyurethane-Single-walled carbon nanotube (SWNT) by the different mass ratios of metronidazole benzoate were prepared. Physico-chemical characterization of scaffolds including Scanning electron microscopy (SEM), uniaxial tensile testing and Ultraviolet-Visible (UV-Vis) spectroscopy analysis was operated. Culture of dental pulp stem cells (DPSCs) to evaluate cells behavior was carried out. The role of nanofiber diameters and drug content on releasing profile of the scaffolds was investigated. The median diameter of the nanofibrous scaffold was reduced from 330 ± 4 to 120 ± 4 nm. Ultimate stress and Young modulus of the scaffolds by enhancement of drug content increased from 0.28 ± 0.05 up to the 1.8 ± 0.05 MPa and 0.87 ± 0.05 up to the 4.4 ± 0.05 Mpa respectively. According to the result, prolonged and continuous releasing profile of the drug molecules was achieved. As the content of the drug increased, the drug was released continuously. It means that two parameters of fiber's diameter and drug ratio affected the releasing behavior of composite structures. Polyurethane-SWNT scaffolds contained metronidazole benzoate presented appropriate support of DPSCs adhesion and proliferation and biomimetic architecture like the structure of dental ECM.