of the posterior maxilla. Inadequate posterior alveolus,
increased pneumatization of maxillary sinus,
and close approximation of sinus to crestal bone limit
the bone volume necessary for a successful implant
placement, especially in the posterior maxilla.3,4 A
limited height of alveolar ridge prevents the placement
of implants with optimal length. The implant failure
rates have been reported to be as high as 30%-50% in
the posterior maxilla.5