Sinus Lift

Why upper back teeth are the problem area

Your maxillary sinuses are two air-filled spaces that sit directly above your upper back teeth, separated from the roots by a thin floor of bone. In some people that bone is naturally thin to begin with.

Then a tooth is lost. Two things happen at once. The bone that used to support the root begins to resorb, because nothing is stimulating it any more. And the sinus above slowly expands downward into the space the root left behind — a process called pneumatization.

Over a few years, the strip of bone between your mouth and your sinus can thin to a few millimetres. An implant needs considerably more than that to be stable. A sinus lift restores the height so the implant has bone to integrate with. This is why upper back molars and premolars so often need grafting while front teeth and lower teeth usually do not.

How we know whether you need one

A standard dental x-ray is not enough to make this call. We take a 3D cone-beam scan, which shows the exact height and density of bone at the implant site, the position of the sinus floor, and the thickness of the sinus membrane. You will know which of the three situations below applies to you at the consultation, not partway through treatment.

• Enough bone already — the implant goes in without grafting

• Borderline — a smaller lift can often be done at the same appointment as the implant

• Significantly reduced — the lift is done first, and the implant is placed after the graft has matured

The two techniques

When only a few millimetres of extra height are needed, a crestal lift works through the same small opening prepared for the implant itself. Specialized instruments gently raise the sinus floor from below, graft material is placed into the space created, and the implant often goes in during the same visit. It is the less invasive of the two — smaller access, less swelling, quicker recovery.

When more height is needed, a lateral window lift accesses the sinus through a small opening in the side of the upper jaw, above where the tooth used to sit. The sinus membrane is carefully lifted away from the bone floor, and graft material fills the space beneath it. This can create substantially more bone height, but requires a healing period before the implant can be placed.

Which technique you need is determined by the scan, not by preference.

What the appointment is like

The procedure is done under local anesthetic. Most patients are surprised that it feels closer to having a filling than to surgery — there is pressure and sound, but not pain. If dental work makes you anxious, we can discuss sedation options beforehand rather than on the day.

The appointment itself usually runs under an hour for a crestal lift, somewhat longer for a lateral window.

Recovery, and the rules that actually matter

Expect some swelling and mild discomfort for a few days, generally well managed with over-the-counter pain relief. Most people return to normal activity the following day. The instructions specific to sinus surgery are the ones worth taking seriously, because they protect the graft while it settles.

• Do not blow your nose for the first two weeks — the pressure can disturb the graft

• Sneeze with your mouth open, so pressure escapes rather than travelling into the sinus

• No straws, no smoking — suction works against healing

• Avoid heavy lifting and strenuous exercise for several days

• Sleep with your head slightly elevated for the first few nights

How long before the implant goes in

If the lift was done at the same time as the implant, the timeline is the normal implant timeline. If the graft was placed on its own, it typically needs several months to mature into bone dense enough to hold an implant. Larger grafts take longer than smaller ones.

It is not a fast route, and we would rather be straight about that than have you discover it midway. What you get in exchange is a fixed tooth in a position that otherwise would not have supported one at all.

What affects the cost

The main variables are which technique is needed, how much graft material the site requires, whether one site or several are being treated, and whether the implant is placed at the same time or separately.

Because a sinus lift is almost always a step towards an implant rather than a treatment on its own, it makes most sense to look at the total treatment cost rather than the graft in isolation. We go through what drives that on our implant cost factors page, and Cherry financing is available if you would rather spread the cost.

Is it worth it?

The alternative to grafting an upper back site is usually a bridge, a partial denture, or leaving the gap. Each has consequences. A bridge means reducing the teeth either side. A denture does nothing to stop the bone loss continuing. An untreated gap lets the opposing tooth drift downward and the neighboring teeth tip inward, which changes your bite over time.

A sinus lift adds months to the plan. It also makes a fixed, independent tooth possible in a place where it otherwise would not be. For most patients replacing an upper molar, that trade is worth making.