All-on-4 vs All-on-6: What’s the Difference and Who May Need Each?

All-on-4 uses four implants to support a fixed set of replacement teeth in one jaw; All-on-6 uses six. The additional implants change the support arrangement, but the number alone cannot establish which treatment is appropriate. Bone availability, implant positions and the planned bridge all matter.[1]

When comparing All-on-4 vs All-on-6, ask what each recommendation would achieve in your mouth. A useful explanation should connect the proposed implant positions to your examination and replacement teeth. It should also cover healing, maintenance and what happens if the original plan needs to change.

What do the numbers actually mean?

The numbers describe implants per arch, meaning the upper or lower jaw. They do not describe the number of visible replacement teeth. Ask each clinic to specify both the implant count and the planned teeth in the bridge.

The original All-on-4 concept uses two implants towards the front and two tilted implants towards the back. Tilting can make use of available bone in selected cases. “Graftless” descriptions of this concept should not be interpreted as confirmation that every patient can avoid bone grafting.[2]

A fixed bridge stays in place for everyday use; patients do not remove it for cleaning. An implant-retained removable denture is a different restoration, so confirm which option a quotation describes.[3]

Implant selection and immediate loading require separate clinical decisions.[1,4]

Who may be considered for each option?

When four implants may be appropriate

The International Team for Implantology (ITI) recommends at least four appropriately distributed implants for a one-piece fixed full-arch prosthesis. Whether four are sufficient depends on the available bone and proposed bridge.[1]

If a dentist recommends four, ask: “What makes these positions suitable, and what would make you change this plan?” Request the explanation before comparing package names or prices.

When six implants may be considered

Six may be considered when suitable additional sites are available and they serve the planned restoration. Extra implants can also provide options for a bridge made in separate sections, where appropriate.[1]

Ask the dentist to identify the added sites and explain the intended benefit. “More support” needs a patient-specific explanation: where will that support be, and does achieving it require additional treatment?

When neither should be the starting assumption

Remaining teeth should be assessed for preservation before committing to full-arch replacement.[1] Ask for an explanation of the prognosis of any tooth proposed for extraction and the alternatives to removing it.

Overall health, smoking, uncontrolled diabetes and existing oral disease also require assessment. Increasing the implant count does not remove these concerns.[5]

Why can two clinics recommend different numbers?

Different recommendations deserve a comparison of the underlying plans. Ask whether both clinicians assessed the same records and proposed the same final restoration.

Assessment commonly includes an examination and imaging. A cone beam computed tomography scan, or CBCT, provides three-dimensional information about bone and nearby structures such as nerves and sinuses.[3] A photograph of your smile cannot supply that information.

Use the consultation to clarify three points:

1. The proposed bridge: What will its shape and material be? How will appearance, speech and cleaning be assessed?
2. The implant positions: Can the dentist show where each implant would go and explain any differences between the two plans?
3. The alternatives: What changes if you choose the other implant count, need grafting or cannot receive immediate fixed teeth?

If the explanations remain unclear, an independent clinical opinion can help you understand the disagreement before consenting to treatment. Bring both written plans and the available imaging.

Does research show that All-on-6 is better?

Research does not justify a universal claim that six implants are better for every patient. It is also important to distinguish implant survival from freedom from repairs or other complications.

A five-year randomised clinical trial compared four and six implants supporting fixed upper-jaw restorations in 47 patients. Implant survival was comparable. Four implants met the study’s non-inferiority criterion for changes in bone levels around the implants, but the four-implant group experienced more technical complications. Initial and total costs were lower in that group.[6]

These findings illustrate why a single “success rate” cannot describe the whole experience. The trial involved selected patients and upper jaws; it does not determine the appropriate treatment for every lower jaw or complex case. It was also partly supported by an implant manufacturer.[6]

When a clinic quotes a percentage, ask what was measured, over how many years, and whether repairs were counted separately.

Can both options provide teeth on the same day?

Immediate fixed teeth may be possible with either approach in selected patients. Eligibility depends on factors including the implants’ initial mechanical stability in bone, called primary stability. The decision cannot be guaranteed solely from the planned implant count.[4]

Immediate loading means attaching a functioning restoration soon after implant placement. The initial full-arch bridge is often an interim, or temporary, restoration. Bone grafting and other clinical factors may affect whether immediate loading is appropriate.[4]

Before booking, ask for two written timelines:

• The expected sequence if immediate fixed teeth are suitable.
• The alternative sequence, including what you would wear, if they are unsuitable on the day.

Also confirm when the final bridge is expected, how many fitting appointments are planned and which findings could delay the schedule. For international treatment, obtain this information before committing to travel dates.

How should you compare All-on-4 and All-on-6 costs?

Compare written quotations for the same treatment scope. A difference between two totals may reflect bridge materials, preparatory treatment or aftercare as well as implant count. Obtain current, individual prices directly from the clinic.

Request separate confirmation of:

• The treated arch: upper, lower or both.
• Assessment and surgery: imaging, extractions, anaesthesia or sedation, and any proposed grafting.
• Implants and components: manufacturer, model, implant count and connecting components.
• Replacement teeth: temporary and final bridges, their materials, and laboratory and fitting fees.
• Aftercare: planned reviews, adjustments, hygiene appointments and the terms for repairs or replacement.

For overseas care, add travel, accommodation and any return visits to your own comparison. Clarify who handles a problem after you return home and which costs remain your responsibility.

A useful final question is: “If my treatment plan changes after examination or surgery, how will you explain and obtain my agreement to the revised treatment and price?”

What risks and maintenance apply to both?

Both involve implant surgery and ongoing care. Potential complications include infection, failure to heal successfully, injury to nearby nerves or sinus structures, and loose components. Report an implant or restoration that feels loose or painful promptly.[5]

Daily cleaning and regular professional review remain essential. Ask the team to demonstrate cleaning around the proposed bridge and explain your review schedule.[5] Inflammation and bone loss can develop around implants; replacement teeth can also chip or require repair.[3]

Frequently asked questions

Is All-on-6 always stronger than All-on-4?

Implant count alone cannot predict a better clinical outcome. Ask what the proposed extra implants contribute to your restoration, and compare evidence about complications as well as survival.[1,6]

Which option is better if I have bone loss?

That requires assessment of where usable bone remains. Tilted implants may help in selected cases, while some patients need grafting or another approach. A scan and examination are needed to discuss the options.[2,3] See also Niva’s guide to dental implants with bone loss.

Does All-on-4 mean four implants for my entire mouth?

No. It describes four implants supporting one arch. A quotation for both jaws should list the planned implant count and restoration separately for each.

Will either option last a lifetime?

Neither should be sold as a guaranteed lifetime result. Implants can develop complications, and the bridge or its components may need attention even while the implants remain in place.[3,5]

Discuss the reasoning behind your treatment plan

For treatment information, visit Niva Dental’s All-on-4 and All-on-6 service page. If you are considering care at Niva Dental in Bakırköy, Istanbul, ask for an individual explanation of the proposed implant count, alternatives and complete treatment stages before deciding.

This article provides general information and does not establish a diagnosis or personal treatment recommendation. Suitability requires assessment by a dentist.

Sources

1. International Team for Implantology. Number of Implants Placed for Complete-Arch Fixed Prostheses — consensus statements and clinical recommendations.
2. Nobel Biocare. All-on-4 treatment concept. Manufacturer source used for the original treatment configuration, not as independent evidence of superiority.
3. Leeds Teaching Hospitals NHS Trust. Dental Implants — patient information.
4. International Team for Implantology. Loading Protocols for Fixed Prostheses in Edentulous Jaws — consensus statements and clinical recommendations.
5. US Food and Drug Administration. Dental Implants: What You Should Know.
6. Toia M, et al. Clinical Oral Implants Research. Fixed Full-Arch Maxillary Prostheses Supported by Four Versus Six Implants: 5-Year Results of a Multicenter Randomized Clinical Trial.