The difference in one paragraph
Both replace a full arch of teeth with a fixed bridge screwed onto implants. All-on-4 uses four, with the rear two angled to avoid the sinus and make use of available bone. All-on-6 uses six, spreading the load across more points.
The bridge, the materials and the process are otherwise the same. The difference is how much foundation sits underneath it.
When six is the right answer
Six implants are generally indicated where the bone is soft or of lower density, where the patient has a heavy bite or grinds, and on the upper jaw, which is softer than the lower and carries more of the chewing load in full-arch cases.
Six also provides redundancy. If one implant fails to integrate on a four-implant case, the whole bridge is compromised. On six, there is more margin.
For patients who want a full zirconia bridge rather than acrylic, six is often preferred because the heavier restoration puts more load through the implants.
When four is enough
Four is well documented and has long-term survival data behind it. Where bone is dense, the bite is normal and the bridge is a reasonable weight, four implants carry a full arch reliably.
It also means less surgery, less cost and fewer sites to heal. Adding implants that are not needed is not a kindness — each one is a surgical site.
The lower jaw in particular is dense enough that four often does the job comfortably.
What decides it
A CBCT scan. It shows bone height, width and density at each potential implant site, which is what determines how many implants the jaw can hold and where they can go.
Anyone recommending four or six before seeing that scan is guessing. A good sign is a surgeon who says the plan may change once they are operating and can assess the bone directly — that is honesty, not indecision.
Cost difference
Per arch, our featured clinics quote All-on-4 at roughly $3,000 to $6,000. All-on-6 typically adds the cost of two more implants and the associated surgical time, so expect several hundred to a little over a thousand dollars more per arch depending on the system.
In the context of a case where the home-country alternative is $26,000 per arch, that difference should not be the deciding factor. If it is being presented as an upsell rather than a clinical recommendation, that is worth questioning.
What to ask
Ask what your bone density is at each planned site and how that informed the number. Ask what happens if one implant fails to integrate. Ask whether the recommendation would change with a zirconia bridge rather than acrylic.
A surgeon who can answer those three has planned your case. One who cannot has quoted a package.
Common questions
Not universally. Six is better where bone is soft, the bite is heavy, or a heavier zirconia bridge is planned — and on the upper jaw. Where bone is dense, four is well documented and sufficient.
Typically several hundred to around a thousand dollars more per arch than All-on-4, covering two extra implants and the added surgical time.
On a six-implant case there is more margin to restore the arch without redoing everything. On four, the loss of one implant usually compromises the bridge and requires replacement.
A CBCT scan showing bone height, width and density at each site. Any recommendation made before that scan is provisional.
Keep reading
All-on-4 explained
Four implants, one fixed arch. What the technique does and where it falls short.
Read article →How much does All-on-4 cost in Türkiye?
Both jaws from around $7,040. Why per-arch pricing varies so widely.
Read article →Dental implant recovery, day by day
What the first week actually feels like.
Read article →