In this study, commercially pure titanium (Ti-cp) discs were used as substrates. Octacalcium phosphate (OCP) layers were deposited by immersion of Ti-cp discs up to 7 days into Solution for Bioactivity Evaluation (SBE) and characterized by SEM-EDS and XRD. The OCP coatings were doped with cephazolin or cefalexin by individual immersion in 300 ppm of each solution for 24 h at room temperature. The non-existence of mathematical models to explain drug release from these matrixes made the choosing of correct model, a complex process. Five non-linear mathematical methods were employed in order to identify the possible drug release mechanism using Akaike and Bayesian Information Criterion (AIC and BIC respectively) and its derivatives. The best model was Peppas & Sahlin that consider two stages in release: pure diffusion in first stage, and drug dissolution and migration through the porous matrix at second stage.