Recently, stereolithography (SL), one of the most diffused techniques in the rapid prototyping area, has been used to realize surgical guides for the corrected positioning of dental grafts. This paper presents a methodology for the design and fabrication of stereolithographic surgical guides useful in alveolar reconstruction with mandibular block bone grafts. The integration between medical imaging techniques and SL was achieved. The surgical guides built with a SL machine were used as tools for surgical operations. This methodology allowed obtaining the maximum respect of the contiguous anatomical structures, the extraction of a limited amount of bone, a remarkable reduction of the operation time, and no alteration of teeth and inferior lip sensibility. The extraction and the positioning of onlay grafts within the chin resulted to be more precise and predictable using stereolithographic surgical guides.