What Is the Difference Between All-on-4 and All-on-6?
With All-on-4, four implants support a fixed bridge for the whole jaw. The two implants at the back are usually placed at an angle. This lets them use the bone at the front of the jaw, where there is often more of it, and can avoid the sinus in the upper jaw and the nerve in the lower jaw.
With All-on-6, six implants support the bridge. The extra two are placed further back, so the chewing load is spread over more points. This needs enough bone in the back of the jaw, or bone grafting to create it.
In both cases the bridge is fixed. You do not take it out, and it is cleaned in the mouth. Temporary teeth are often fitted soon after surgery when the implants are stable enough, and the permanent bridge follows after healing.
Number of implants
All-on-4: four per jaw. All-on-6: six per jaw.
Bone needed
All-on-4: can work with less bone at the back because of the angled implants. All-on-6: needs bone further back or grafting.
Load distribution
All-on-4: on four points. All-on-6: on six points, with more reserve if one implant fails.
Bridge length
All-on-4: often a shorter bridge. All-on-6: can support a bridge that reaches further back.
Who Each Option Suits
Both are for people who have lost, or are about to lose, all teeth in a jaw.
All-on-4 with limited bone at the back
When bone is thin near the sinus or the nerve, angled implants can make fixed teeth possible without major grafting.
All-on-6 with good bone volume
When there is enough bone further back, six implants give broader support for the bridge.
All-on-6 often in the upper jaw
The bone of the upper jaw is softer, so more implants are often planned there than in the lower jaw.
Bite force and grinding
A strong bite or teeth grinding puts more load on the bridge and can be a reason to plan more implants.
The opposing jaw
Natural teeth in the other jaw bite harder than a denture and influence the plan.
Too little bone for six without grafting
If the back of the jaw cannot hold implants, your dentist may advise All-on-4 or grafting first.
Uncontrolled health conditions
Uncontrolled diabetes, heavy smoking and active gum infection raise the risk of failure with both options and need attention first.
Risks and Limits of Both Options
These apply to any full-arch implant bridge.
Implant failure
An implant can fail to bond with the bone. With four implants there is less reserve, so a failed implant is more likely to need replacing before the bridge can be used.
Cleaning under the bridge
Food and plaque collect under a fixed bridge. Cleaning under it every day is essential with either option.
Wear and repairs
Bridge teeth can chip or wear over the years and screws can loosen. The bridge is removed by the dentist for maintenance.
Inflammation around implants
Peri-implantitis can affect any implant and is more likely when cleaning is difficult or neglected.
How the Choice Between Four and Six Implants Is Made
The decision is made on your scan, not by preference. Treatment follows the same steps with either option.
- 1
Examination and 3D scan
A CT scan shows how much bone you have in each part of the jaw and where the sinus and nerve lie.
- 2
Planning the implant positions
Your dentist plans where implants can be placed securely and whether four or six positions are available without grafting.
- 3
Surgery and temporary teeth
Remaining teeth are removed if needed and the implants are placed. If the implants are stable, a temporary fixed bridge is fitted within days.
- 4
Permanent bridge after healing
After a healing period of a few months, the permanent bridge is made and fitted on a second visit.
Other Options to Discuss
All-on-4 and All-on-6 are not the only ways to replace all teeth.
Implant-retained overdenture
A removable denture that clips onto two to four implants. It is taken out for cleaning.
Conventional full denture
A removable denture without implants, for people who cannot or do not want to have surgery.
Individual implants and bridges
When several healthy teeth remain, replacing only the missing teeth may be the better plan.
How Papatya Dental Clinic Plans Full-Arch Treatment
Ask to see on your scan where each implant is planned and why four or six are proposed for your jaw.
3D CT planning
Bone height, width and nearby structures are measured on a 3D CT (CBCT) scan before the implant is chosen.
In-house laboratory
Crowns are made in the clinic's own CAD/CAM laboratory, so shade and shape can be adjusted during your visit.
Implant card
You receive a card showing the brand and size of your implant, so any dentist can maintain it later.
Healing and Aftercare
Recovery is similar with four and six implants.
- 1
First week
Swelling and bruising are common and usually peak on the second or third day.
- 2
Healing months
You eat soft food while the implants bond with the bone. The temporary bridge stays in place during this time.
- 3
Permanent bridge
After healing, the permanent bridge is fitted and your bite is adjusted.
Clean under the bridge every day
Use the brushes, floss or water flosser shown by your dentist to clean between the bridge and the gum.
Keep your check-ups
Regular check-ups and professional cleaning help spot problems around the implants early.
Increasing pain, swelling or fever
Contact the clinic if symptoms get worse after the first few days instead of improving.
A loose crown or implant
Do not chew on that side and get in touch so it can be checked.
What Shapes Your Treatment Plan
Your plan is confirmed after an examination and CT scan. These factors influence it most.
Number of implants
Six implants mean more surgery and more components than four.
Bone grafting or sinus lift
If bone has to be built up first, treatment takes longer.
Bridge material
The permanent bridge can be made from different materials, such as zirconia or acrylic on a metal frame.
One jaw or both
Treating both jaws is planned together so the bite fits.
Before / After
Frequently Asked Questions About All-on-4 and All-on-6
Is All-on-6 better than All-on-4?
Not automatically. Six implants spread the load more, but only if the bone can hold them. Four well-placed implants can be the right plan when bone is limited.
Do I need a bone graft?
It depends on your scan. All-on-4 is often chosen to avoid grafting at the back of the jaw. All-on-6 may need grafting or a sinus lift.
How soon will I have teeth?
A temporary fixed bridge is often fitted within days of surgery when the implants are stable. The permanent bridge is made after healing.
How many trips are needed?
Usually two: one for surgery and temporary teeth, and one a few months later for the permanent bridge.
What if one implant fails?
The implant can usually be replaced after healing. With six implants the bridge may still be supported in the meantime, with four this is less likely.
How do I clean an All-on-4 or All-on-6 bridge?
You brush the bridge like teeth and clean underneath it every day with special brushes, floss or a water flosser.