The Analytic Hierarchy Process (AHP) is a methodology, based on both mathematical and psychological approaches, exploited to analyze and solve complex problems, in order to make the best decision. AHP is also widely employed for the evaluation of healthcare systems. It works by splitting the decision problem into a hierarchy of more easily-comprehended sub-problems, each of which can be independently analyzed. Starting from these assumptions, our work aims to implement a dynamic framework for the AHP methodology, able to overcome the static nature of the technique, taking into account the evaluations associated with criteria and sub-criteria as a function of time. In the context of this paper, the Dynamic AHP is implemented as a tool for Health Technology Assessment (HTA). Indeed, the proposed case study concerns the evaluation of a new health technology for the thyroglobulin assay in patients with differentiated thyroid cancer. To this aim, we have defined the decision problem and formalized criteria and sub-criteria hierarchically; then, in order to deal with the problem from a dynamical point of view, i.e., to take into account the time dependence of criteria and sub-criteria, we developed several System Dynamics models, one for each criterion. In this context, it is shown that the Dynamic AHP approach provides a dynamic evaluation of the system, which allows to identify the best decision by exploiting the information on the possible evolution of the problem due to its time behavior, rather than taking the decision at a fixed time point, as the Static AHP does.