In this paper a model-based approach for restoring a continuous fundamental frequency (F0) contour from the noisy output of an F0 extractor is investigated. In contrast to the conventional pitch trackers based on numerical curve-fitting, the proposed method employs a quantitative pitch generation model, which is often used for synthesizing F0 contour from prosodic event commands for estimating continuous F0 pattern. An inverse filtering technique is introduced for obtaining the initial candidates of the prosodic commands. In order to find the optimal command sequence from the commands efficiently, a beam-search algorithm and an N-best technique are employed. Preliminary experiments for a male speaker of the ATR B-set database showed promising results both in quality of the restored pattern and estimation of the prosodic events.