Intentional angulation of an implant to avoid a pneumatized maxillary sinus: a case report

This case report describes placement of an implant in the posterior maxilla so as to avoid a pneumatized sinus and also to avoid the need for a sinus lift procedure. An 81-year-old woman presented with an edentulous span in the upper right posterior maxilla. She had been missing teeth in this area for many years, and there was a combination of resorption of the alveolar ridge and pneumatization of the maxillary sinus. Eleven years previously, implants had been placed anterior to this region, but the patient was told that implants could not be placed posteriorly unless a sinus lift was done. At the time of the current presentation she was still unwilling to undergo a sinus lift procedure but wanted to know if implants could be placed in the posterior right maxilla. A tomogram obtained with a radiographic stent in place indicated that there was insufficient bone height to allow placement of implants at the usual angulation without a sinus lift. Therefore, to avoid the need for a sinus lift, 2 implants were placed with palatal angulation as guided by a tomographically determined surgical stent. The treatment planning and surgical and restorative techniques are reviewed here. A postoperative tomogram was obtained to determine the final position of the implants. The outcome has been favourable for the patient and the clinicians. In situations where there is sufficient palatal bone medial to the maxillary sinus, placing implants at an angle may prevent the need for a sinus lift procedure, assuming that proper development of an occlusal restorative scheme is possible.