ObjectiveThis study aimed to understand the effect of gamma irradiation on the microstructure, composition and microfriction and wear properties of human tooth enamel.MethodsNanoscratch tests, surface profilometer and scanning electron microscope analysis were used to evaluate the friction behaviour of human tooth enamel slabs before and after gamma irradiation. X-ray diffraction and Fourier transform infrared spectroscopy were performed to analyse changes in crystallography and chemical composition induced by irradiation. Surface microhardness alteration was also evaluated.ResultsAfter irradiation, additional partial packing and delamination with high friction coefficient were observed in the enamel. The Knoop hardness number (KHN) of the enamel significantly decreased from (420±20) KHN before irradiation to (333±11) KHN (PPPPConclusionGamma irradiation decreased the wear resistance of enamel. Results should be considered when performing clinical restorations.
