human 81 Humans 73 Scanning electron microscopy 55 procedures 48 chemistry 45 Article 41 resin 41 Composite Resins 39 Tensile strength 36 Morphology 33 Fourier transform infrared spectroscopy 32 Mechanical properties 29 controlled study 29 Reinforcement 27 in vitro study 25 Nanocomposites 24 Nanostructured materials 24 Compressive strength 23 Fibers 22 In Vitro Techniques 22 Composite materials 21 Silica 21 dental restoration 21 Dental Restoration, Permanent 20 male 20 Glass 19 comparative study 19 Nanoparticles 18 female 18 surface property 18