The effect of silk concentration on the flexural strength of FRC as a Bone Graft

Bone fractures are mostly caused by trauma and disease. In the therapeutic process of bone healing which often meets some constraints, bone graft is mainly used to ensure that the healing process takes place. A fiber reinforced composite (FRC) is a popular bone graft material that is made to resemble bone properties. FRC is normally comprised of polymer matrix, hydroxyapatite filler, and fiber. Hydroxyapatite is a bioactive material widely used as a bone graft. Silk fiber is known as a reliable material to increase mechanical strength of the FRC. On this basis, this study aims to determine the effect of silk fiber concentration on the flexural strength of FRC. Fiber reinforced composite made of Bis-GMA/TEGDMA/ UDMA resin (CharmFil®, DenKist, Korea), hydroxyapatite (Bioceramic Laboratory, DTMI UGM) and silk fiber (Perhutani, Pati) were divided into three groups. Each group contained different silk fiber concentrations which were 1%, 5% and 10%. The flexural strength test was performed with 3-point bending test according to ISO 10477. The result showed that FRC with silk fiber 1%, 5% and 10% respectively had flexural strength of 61.21 ± 8.43 MPa, 62.97 ± 3.92 MPa and 85.01 ± 7.71 MPa. The result of one way ANAVA analysis showed that mean of FRCs flexural strength were significantly different between one treatment group to another. Thus, it is conclusive that silk fiber has a significant effect on FRCs flexural strength. The addition of 10% concentration of silk fiber is proven to increase FRCs flexural strength.