Sinus Graft

Many people wonder what sinus lift (or sinus grafting) is and when and why it is done.  By sinus, dentists mean the maxillary sinus.  In general, a sinus is an air-filled space within bone in the head.  There are quite a few sinuses in the head, and there are two maxillary sinuses, on the right and left side, underneath the eyes and above molar teeth (back teeth).

The maxillary sinus becomes larger in size with age.  It tends to enlarge itself, over the area where the molar teeth roots are, after the molar teeth are lost.  Sometimes the lower bony wall of the sinus becomes very thin, sometimes so thin that there is no appreciable amount of bone left at all especially in cases where molar teeth has been lost for a long time.

Since dental implants are placed in the bone and anchored by bone, areas with little bone presents a problem when dental implants are planned.  The maxillary sinus area, the molar teeth (back teeth), is especially a problem with dental implants.  There usually is not enough bone to place dental implants in the area.  In order to augment the area, bone can be added either from the sinus side or the oral cavity side.  The decision depends on many factors.  The grafting of bone from the sinus side is often called sinus lifting or sinus grafting.  By adding bone at the sinus floor (from the sinus side) and allowing the graft to take, dental implants of adequate sizes can be placed into the bone in the upper molar area.