Bone and anatomy
Bone volume and quality, sinus position, nerves and the distribution of available support influence whether four, six or another number of implants can be considered.
Full-arch implant treatment
All-on-4 vs All-on-6 Dental Implants: Understanding Full-Arch Support
Implant number is one part of a much wider restorative decision
All-on-4 and All-on-6 describe fixed full-arch bridges supported by four or six implants. Neither is automatically the better solution. Bone anatomy, implant position, arch shape, biting forces, bridge design and cleaning access must be assessed for each patient.
The underlying concept
What Do “All-on-4” and “All-on-6” Mean?
A full-arch bridge replaces all the teeth in one jaw and remains secured to its implants between professional maintenance appointments. The implants act as foundations; the bridge connects them across the arch.
The number of implants does not by itself determine strength, longevity or suitability. Four well-positioned implants may be appropriate in one jaw, while another patient may benefit from six or require a different design entirely.
Simplified mechanics
How the Support Arrangements Differ.
[Implant]────[Implant]────[Implant]────[Implant]
The posterior implants may be angled to increase the support span and help limit, but not always eliminate, unsupported bridge sections behind the final implants.
[Implant]─[Implant]─[Implant]─[Implant]─[Implant]─[Implant]
Additional, appropriately positioned implants may provide broader support and reduce the load carried by each implant and component.
Simplified illustration—not to scale. Implant number alone does not determine the strength or suitability of a full-arch bridge.
Individual selection
What Determines the Appropriate Configuration?
Bite and bridge design
Arch shape, bridge length, opposing teeth, tooth grinding and the position of the final teeth determine how forces will be managed.
Cleaning and maintenance
The bridge must allow effective daily cleaning. Gum history, dexterity and willingness to attend reviews are part of suitability.
Documented clinical experience
A Full-Arch All-on-6 Case.
One documented case involved extensive deterioration across both jaws, chronic periodontal disease, failing historical restorations and a heavy bite. Three healthy existing upper implants were incorporated with three newly placed implants into a six-implant support arrangement.
Local grafting and sinus augmentation were undertaken where required. A reinforced provisional bridge was fitted only after implant stability was assessed, followed by a definitive zirconia-and-porcelain bridge after monitored healing.
Risks, Limits and Maintenance
Full-arch treatment is not maintenance-free. Integration can fail, gum inflammation and supporting-bone loss can occur, and screws or restorative materials may loosen, chip or wear. Same-day fixed teeth are conditional on implant stability and cannot be guaranteed before surgery.
Natural teeth with a maintainable prognosis should not be removed merely to provide an implant bridge. Alternatives, staged treatment and the expected maintenance burden should be discussed before consent.
This page provides general information. The clinical case is an individual example and does not predict another patient's suitability, healing or outcome.