Understanding Implant Numbers and the Role of Zygomatic & Pterygoid Implants

When considering full arch dental implant rehabilitation, patients often ask whether four implants are truly sufficient—or whether six or more are better. The short answer? It depends entirely on your unique bone anatomy, oral condition, and long-term functional goals.

Let’s break it down clinically.

What Is All-on-4?

The All-on-4 technique refers to a prosthetic full arch restoration supported by four strategically placed implants. Two anterior implants are placed vertically, while two posterior implants are tilted at an angle to maximise available bone and avoid anatomical structures like the sinus in the upper jaw or the nerve in the lower jaw.

This method provides strong anterior-posterior (A-P) spread, often without the need for bone grafting. It’s cost-effective, minimally invasive, and works well for many patients with moderate bone loss.

When Do We Use All-on-6?

All-on-6 involves placing six implants, typically to further improve load distribution and increase the A-P spread. This configuration is often preferred when:

• The patient has stronger residual bone

• There is a history of bruxism

• We’re aiming to minimise cantilever forces

• The prosthesis needs to support heavier biting loads

In short, All-on-6 can provide an extra layer of biomechanical security—but it’s not always necessary.

Zygomatic and Pterygoid Implants: Extending the Reach

In patients with severe bone loss, especially in the upper posterior maxilla, traditional implants may not be possible without grafting. Instead, we use zygomatic and pterygoid implants to bypass compromised areas:

• Zygomatic implants anchor into the cheekbone (zygoma), providing posterior support without sinus lifts.

• Pterygoid implants extend into the pterygoid plates behind the upper jaw, giving firm anchorage in dense cortical bone.

Both options increase A-P spread dramatically, reducing cantilever forces and improving prosthetic stability—critical for long-term success.

Which Is Right for You?

There’s no one-size-fits-all answer. Your treatment plan is tailored based on 3D imaging, bone volume, and your specific anatomical limitations. At our practice, we routinely evaluate whether a conventional All-on-4 is sufficient—or whether more advanced options like zygomatic or pterygoid implants are needed.

The goal is always the same: a stable, natural-looking, and long-lasting smile built on a strong foundation.

Read more here: https://www.samintharajkumar.com.sg/2ndopinions