Comparative study of compressive and fatigue strength of dental implants made of nanocrystalline Ti Hard and microcrystalline Ti G4

Over the last decades, much research has been done to improve the surface quality of dental implants, but there was no change in the materials used to manufacture the implants. The purpose of the present work is to compare the compressive strength and fatigue failure of dental implants made with a new material, nanocrystalline Ti grade 4 fabricated by Equal Channel Angular Pressing (ECAP) (Ti Hard) with a traditional material, microcrystalline Ti grade 4 (Ti G4). Machined screw-shaped implants with three different designs (Easy, Torq and Flash) made with the two materials were subjected to static and dynamic compressive loads. Implants made with Ti Hard showed higher static compressive strength (Easy: 889.9 +/- 79.4 N, Flash: 588.9 +/- 74.7 N, Torq: 498.3 +/- 54.6 N) than implants made with TiG4 (Easy: 776.4 +/- 74.5 N, Flash: 308.8 +/- 15.2 N, Torq: 410.3 +/- 25.2 N) and higher fatigue strength for 5 10(6) cycles (Easy: 400 N, Flash: 280 N, Torq: 260 N) than implants made with TiG4 (Easy: 300 N, Flash: 200 N, Torq: 200 N). The higher fatigue strength of nanocrystalline Ti G4 is attributed to a delay in crack initiation.