This investigation studies the effect of the shot-blasting treatment on the cyclic deformation behavior of a commercially pure titanium, with two microstructures: equiaxed and acicular. The fatigue tests were carried out in artificial saliva medium at 37° C. Cyclic deformation tests have been carried out up to fracture, and the fatigue crack nucleation and propagation have been analyzed. The results show that the shot-blasting treatment improves the fatigue life in the mi-crostructures studied, and that the equiaxed was better in mechanical properties than the acicular. The cause of this improvement in the mechanical properties is due to the compressive stress on the material surface for the shot-blasted specimens. Hardness tests were carried out to determine the value of these internal stresses.