Bone in the upper posterior area of the mouth is often limited due to the sinus. Sinuses are naturally occurring air spaces above the upper teeth.  When these teeth are lost, the sinus frequently expands, preventing the placement of dental implants. 

A sinus lift procedure is often used to increase the amount of bone available for the placement of dental implants.  The sinus floor is gently elevated and bone replacement material is used to allow adequate room for the placement of dental implants.