Two Sinuses, One Surgeon, One Variable

“In implant surgery, biology is constant — but humans are variable.” andré chen

This week brought an interesting clinical reflection.

I was waiting for the local supermarket Aucham to open this morning here in Benfica neighborhood,,, when I started thinking about a case we performed this week: a sinus elevation in the region of tooth #16. The CBCT clearly showed a severely pneumatized maxillary sinus and almost no residual bone. The patient, interestingly, had no idea this was the situation.

After discussing the options with her, the decision was clear: maxillary sinus elevation.

In these situations, there is always a classical clinical dilemma.

One could consider a three-unit bridge, or if going the implant route, the question becomes:

Should we perform a closed sinus lift or an open lateral window approach?

The closed approach — using the Summers osteotomes or what is now often called osseodensification — certainly has its indications. When you have 6–7 mm of residual bone and want to gain 1–2 mm, this technique can work well.

I have absolutely nothing against it. (This sentence really shows my thoughts 💭 on the technique…. I’m trying to be polite here …🤣)

However, when you are trying to move from 1–2 mm of bone to 10–12 mm, the biology changes completely.

In those cases, in my opinion, the only predictable solution is the lateral window approach, exposing the medial wall of the sinus and elevating the Schneiderian membrane to allow proper graft placement and, most importantly, proper vascular supply.

This is not a revolutionary idea.

For anyone interested in the foundations of sinus grafting, I always recommend reading the classic work of Ole T. Jensen — “The Sinus Bone Graft.” That book beautifully describes the historical evolution of the technique, from ENT antroscopy procedures (Caldwell Luke ) to the partial antrostomy approach used today in implant dentistry. (Modified Caldwell Luke Aproach)

The Technical Nuances

Two elements are critical in a lateral window sinus elevation:

1. Proper window design

The lateral window must be large enough to allow the insertion and manipulation of instruments. One of the biggest difficulties in sinus surgery is simply the limited working space inside the sinus cavity.

If the window is too small, surgical control becomes difficult.

2. Proper instruments

Sinus surgery requires instruments with multiple angulations to safely detach the Schneiderian membrane.

The window itself can be prepared using either:

• a piezoelectric device

• or a round diamond bur

Personally, I prefer the piezo. The tips are ergonomic and allow precise osteotomies with minimal risk of membrane perforation.

The Interesting Part of the Week

What made this week interesting was not the technique.

It was the patients.

We performed two sinus elevations under almost identical conditions:

• Same surgeon

• Same technique

• Similar sinus anatomy

• Similar residual bone

But one variable changed everything.

Patient compliance.

One patient was calm, relaxed, completely cooperative during the procedure.

The other patient was extremely nervous, tense, and unable to remain still.

And in sinus surgery, time and stability matter enormously.

When we looked at the postoperative CBCT scans, the difference was striking.

In the calm patient, the biomaterial showed excellent condensation and distribution within the sinus cavity.

In the nervous patient, the condensation was clearly less homogeneous and less compact.

Same surgery.

Same operator.

Same indication.

Completely different graft behavior.

Will Both Work?

Most likely, yes. Because the medial wall was exposed on both sides, so vascularization is definetly on !!

Both grafts will probably integrate.

But if we look at it from a biological perspective, it is quite possible that the second case — the calm patient — will develop a higher percentage of vital bone formation compared with the first.

Because surgical precision and graft stability directly influence the biological cascade that follows.

A Final Thought on Closed Sinus Techniques

This is also why I remain cautious with atraumatic sinus lift techniques.

When we see the characteristic “dome” on the radiograph created by osteotomes or osseodensification, what we are often seeing is mainly biomaterial displacement, not necessarily true vascularized bone formation.

Without proper elevation of the sinus membrane and adequate vascular supply, the biological potential of the graft is limited.

Radiographically impressive does not always mean biologically optimal.

Clinical Pearl

1- Two identical sinus lifts can produce completely different outcomes.

2- Sometimes the difference is not the surgeon.

Not the technique.

Not even the biomaterial.

Sometimes the difference is simply the patient sitting in the chair.

And that was the reflection of the week.

Now the bakery is open, and it’s time to buy bread for the weekend.

Good morning and go climb !!!🧗

Andre