A method is presented which restricts the space of paths entering the path integral of quantum mechanics to subspaces of C α , by only allowing paths which possess at least α derivatives. The method introduces two external parameters, and induces the appearance of a particular time scale D such that for time intervals longer than D the model behaves as usual quantum mechanics. However, for time scales smaller than D , modifications to standard formulation of quantum theory occur. This restriction renders convergent some quantities which are usually divergent in the timecontinuum limit → 0. We illustrate the model by computing several meaningful physical quantities such as the mean square velocity v 2 , the canonical commutator, the Schrodinger equation and the energy levels of the harmonic oscillator. It is shown that an adequate choice of the parameters introduced makes the evolution unitary.PACS numbers: