What Is a Partial (Internal) Sinus Lift?

A partial (internal) sinus lift is the conservative way to build bone at a single implant site in the upper back jaw. When the CT scan shows some bone beneath the sinus, just not quite enough to hold a dental implant safely, we gently raise the sinus membrane at that one spot, working through the implant preparation itself, and place bone graft material beneath it. In most cases the implant is placed at the same visit.

No separate surgical site. No months of waiting before the implant can go in. It is the smallest procedure that honestly solves the problem, which is exactly why it is used only when the anatomy supports it.

How the Internal Technique Works

Every implant begins with a precisely prepared channel in the bone, called an osteotomy. When the bone under the sinus is a few millimeters short, we use a specialized instrument called an osteotome to gently elevate the sinus membrane upward through that channel (Fig. 1 shows a typical starting point: a broken tooth destined for extraction).

Bone graft material is then introduced beneath the lifted membrane, creating a stable pocket of future bone above the implant site (Fig. 2). The implant is placed immediately into the newly created space (Fig. 3), often at the very appointment the failing tooth is removed, provided the implant can be seated with firm initial stability.

Fig. 1: Broken Tooth

Fig. 2: Tooth Extracted, Bone Graft Placed

Fig. 3: Sinus Lifted with Bone Graft, Implant Inserted

The Stability Rule That Governs Everything

Combining the graft and the implant in one visit is appealing, and often appropriate. But it is governed by a firm rule: the implant must achieve at least half its threads in stable native bone. That anchorage is what holds the implant motionless while the graft above it matures. Without it, the implant would move during healing, and movement is the enemy of osseointegration.

When that stability cannot be achieved, the correct answer is to stage the treatment rather than force a same-day result. This is the same judgment that runs through all of our surgical planning: the sequence serves the outcome, never the other way around.

Internal or External: The Scan Decides

The internal lift has a natural limit. It adds a modest amount of height at a single site, which is ideal for one or two implants with reasonable existing bone. When the sinus floor has dropped dramatically and little or no bone remains, the site needs a full (external) sinus lift, a separate rebuilding procedure done months before implants.

Neither technique is better in the abstract; each is better for a specific anatomy. Our overview of when a sinus lift becomes necessary walks through the situations that lead to each, and the choice for your site is made from 3D measurements during planning, the same discipline behind precision implant placement.

Healing and What Comes Next

Expect 4 to 6 months of quiet integration, depending on bone quality, while the graft matures and the implant fuses with your bone. Discomfort is typically minimal because there is no second surgical site. Once integration is confirmed, the implant is restored with an abutment and crown from our in-house laboratory, designed to serve for the long term.

If an upper back tooth is failing, or you have been told bone is borderline at an implant site, get the measurement before assuming the worst. Call 202-244-2101 or request a consultation with Dr. Gerald Marlin, a specialty-trained prosthodontist, at Elite Prosthetic Dentistry in Friendship Heights, Washington, DC.