Mechanical strength comparison of natural resources composite resin with coconut coir (<i>Cocos nucivera L.</i>) particulate fiber 70% cellulose filler and RMGIC

Abstract One of the intermediate layer materials that use in dentistry is flowable composite resin. Synthetic fiber usage as filler for composite resin has relatively weak adhesion to the polymer matrix components causing low mechanical strength. Coconut coir filler as natural resources have good interfacial bonding with matrix resin, low toxicity, quite low modulus of elasticity and very high elongation at break. Mechanical tests on the intermediate layer material need to be carried out in order to minimize microleakage and be able to withstand chewing loads in the oral cavity. This research aimed to determine the differences in the mechanical strength of coconut particulate fiber 70% cellulose filler composite resin and RMGIC. Samples divided into two control groups and a treatment group, which contain 6 samples for each group. All samples underwent a flexural strength modulus of elasticity, impact strength and compressive strength test. The results show that the flexural strength value was p=0.092 (p&gt;0.05), impact strength value was p=0.065 (p&gt;0.05), compressive strength value was p=0.850 (p&gt;0.05). There was no differences in mechanical strength between the coconut particulate fiber 70% cellulose filler composite resin and RMGIC. This research supports the development of natural treatments and natural resources.