PURPOSE: This article reviews the literature on maxillary implant-supported overdentures.

Retrospective studies and clinical reports comprise the majority of publications, with few prospective studies.

Maxillary
implant-supported overdentures are associated with implant and
prosthesis survival rates similar to those of fixed implant prostheses
when patients are matched for bone quantity and quality. High failure
rates are associated with extreme atrophy, poor bone quality, and the
use of short implants, which represent situations in which overdentures
are most commonly used.

Further research is
required to elucidate the most appropriate implant number and
distribution as well as the most favorable prosthetic constructions.