Single-tooth osteotomy is a surgical technique in which the tooth and adjacent bone with sufficient soft tissue are repositioned in a single step or moved orthodontically. It is not used in the maxillary posterior region because of poor accessibility, bleeding complications, and anatomical limitations such as the maxillary sinus. However, the development of piezoelectric surgical devices and the popularization of the sinus floor elevation procedure have simplified the approach to the posterior maxillary area. This article reports two cases of single-tooth osteotomy of ankylosed teeth that were performed safely in the posterior maxilla with the use of a piezoelectric device and a sinus membrane elevation. In addition, several merits of this approach as compared with conventional osteotomy are described.