INTRODUCTION Developing a successful bone tissue engineering strategy entails translation of experimental findings to clinical needs. A major leap forward towards this goal is a quantitative tool to predict spatial and temporal bone formation in scaffold. We hypothesized that bone formation in an osteoconductive scaffold follows diffusion phenomenon. In order to identify the proposed model, we implanted PLA/β-TCP scaffolds in distal femur of rats and measured bone formation using longitudinal micro-CT imaging. We then validated the proposed model using two other published in vivo models