The maxillary sinus elevation is a standard and predictable procedure allowing the realization of dental implant rehabilitation in patients with severe bone atrophy in the lateral-posterior areas of the maxilla. Despite the presence of validated surgical methods and the broad availability of biomaterials, the procedures aimed at increasing the bone volume by lateral antrostomy still entail complications with different degrees of relevance. The prosthetic and surgical outcome is based on a successful coping with these aspects. The perforation of the Schneiderian membrane is one of the most frequent events for which a variety of protocols and approaches have been suggested by different authors. In this work is presented a case study in which a technique to repair the sinus mucosa laceration occurring during a maxillary sinus elevation procedure has been successfully adopted.