What Is a Full (External) Sinus Lift?

A full (external) sinus lift is the bone grafting technique we use when the upper back jaw has little or no bone left beneath the sinus. Working from the cheek side, we gently raise the sinus membrane and pack bone graft material into the space beneath it, rebuilding the height of the ridge so that dental implants can eventually be placed.

It is the more extensive of the two sinus lift techniques, and it exists for a reason: some sites are simply too depleted for anything less. Where the conservative internal lift adds a few millimeters through the implant site itself, the external lift reconstructs the entire sinus floor on that side.

When the External Technique Is the Right One

The deciding factor is how much bone remains between your ridge and the sinus floor. When a usable amount is present, an implant can often be placed with a modest internal sinus lift at the same visit. When the CT scan shows almost nothing to work with (Fig. 1), attempting to shortcut that reality is how implants fail. The honest answer is to rebuild the bone first.

That finding is made during 3D planning, not guessed at chairside. If you are earlier in your research, our overview of when a sinus lift is necessary explains the situations that lead patients here.

How the Procedure Works, Stage by Stage

Through a small opening on the cheek side of the upper jaw, the Schneiderian membrane (the delicate lining of the sinus floor) is carefully elevated, staying intact throughout. Bone graft material is then packed into the space created beneath it (Fig. 2), covering the floor of the sinus on that side.

Then biology takes over. Across roughly 6 to 9 months, the graft consolidates into dense, living bone. Once it has matured, implants are placed into the new bone (Fig. 3). About four months later, after the implants have integrated, they are restored with abutments and crowns fabricated in our in-house laboratory (Fig. 4).

Fig. 1: No Bone Available to Receive Any Implant

Fig. 2: Bone Filled-In Below Sinus Membrane Using a Full (External) Sinus Lift Process

Fig. 3: Implants with Final Abutments and Crowns in New Bone

Fig. 4: Final Abutments and Crowns Seated on Implants

Why the Waiting Is the Point

Patients sometimes ask whether the months of graft maturation can be compressed. The honest answer: the timeline is the treatment. An implant placed into immature graft is an implant asked to fail. Staging the reconstruction, letting each phase prove itself before the next begins, is the same philosophy behind staged implant therapy, and it is why sites rebuilt this way can carry teeth for decades rather than years.

This matters whether you arrived here through a long history of missing teeth or you are proactively replacing dentistry that is reaching the end of its life. Done correctly once, an external sinus lift is not a detour from your implant treatment. It is the part of the treatment that makes everything above it possible.

Comfort, Recovery, and What to Expect

The procedure is performed under local anesthesia, with sedation available if you would like it, and most patients report far less discomfort than the name suggests. Expect soft foods for the first week and some precautions to protect the healing membrane, such as avoiding forceful nose blowing. Normal routines resume quickly while the graft quietly matures underneath.

Find Out What Your Upper Jaw Needs

If you have been told there is not enough bone for upper implants, the next step is a measurement, not a guess. Dr. Gerald Marlin, a specialty-trained prosthodontist with more than 3,900 implants placed and restored, will review your 3D scan and lay out exactly what your site requires. Call 202-244-2101 or request a consultation at Elite Prosthetic Dentistry in Friendship Heights, Washington, DC.