What Are All-on-4 and All-on-6?
All-on-4 and All-on-6 are implant-supported full-arch restorations that replace every tooth in the upper or lower jaw using only four or six titanium implants as anchors. A fixed prosthetic bridge — usually crafted from zirconia or high-strength acrylic — is secured onto these implants, delivering results that look, feel, and function like natural teeth.
Both systems are a dramatic improvement over conventional removable dentures, which can slip, limit food choices, and allow bone loss to continue unchecked. Because the implants transmit chewing forces directly into the jawbone, they stimulate bone maintenance in the same way natural tooth roots do.
All-on-4: Full Arch Restoration with Four Implants
How It Works
The All-on-4 concept was developed to maximise the use of available bone while avoiding complex grafting procedures. Two implants are placed vertically in the front of the jaw and two are inserted at an angle of approximately 30 to 45 degrees toward the back. This angular placement allows the posterior implants to engage denser anterior bone, bypasses the maxillary sinuses, and creates a wide support quadrilateral — all without bone grafting in the majority of cases.
Bone Requirements
Because the angled posterior implants reach into regions of higher bone density, All-on-4 can often be performed when bone volume is borderline or moderately reduced. In the upper jaw this usually means that sinus lifting is not required, making treatment faster and less complex. Your clinician will confirm suitability with a CBCT scan.
Who Is All-on-4 Best Suited For?
- Patients who have lost all teeth in one or both jaws, or whose remaining teeth are beyond salvage
- Those with limited bone volume who want to avoid bone grafting or sinus lift procedures
- Patients prioritising a shorter overall treatment timeline
- Those looking for a more cost-accessible full-arch solution
Advantages of All-on-4
- Fewer implants means a shorter surgical procedure and reduced anaesthesia time.
- Angled implants frequently eliminate the need for bone grafts or sinus lifts.
- Same-day temporary bridge is possible with "immediate loading" — patients leave the clinic with a functional smile the same day as surgery.
- Lower overall cost compared to All-on-6, owing to fewer implants and potentially fewer preparatory procedures.
- High documented long-term success rates when patient selection is appropriate.
All-on-6: Enhanced Stability with Six Implants
How It Works
All-on-6 distributes the prosthetic load across six implants, typically placed in a balanced pattern from the front to the mid-posterior region of the jaw. The additional two implants create a broader support base and spread occlusal forces over a larger area of bone, improving long-term biomechanical stability.
Bone Requirements
All-on-6 requires sufficient bone volume throughout a wider area of the jaw, including more posterior regions. Patients with adequate bone height and density — confirmed by CBCT — are the primary candidates. In some cases, minor bone augmentation may still be required for the most posterior implant positions.
Who Is All-on-6 Best Suited For?
- Fully edentulous patients with adequate bone volume across the jaw arch
- Patients with bruxism (nocturnal tooth grinding or clenching), who generate higher-than-average bite forces
- Those planning a wider-span posterior bridge segment
- Patients seeking maximum long-term security and load distribution
- Anyone for whom premium longevity justifies the additional investment
Advantages of All-on-6
- More implants optimise force distribution — each implant bears less load.
- Greater resistance to high occlusal forces makes it the preferred choice for bruxism patients.
- Wider posterior support can allow a longer bridge span, accommodating more prosthetic teeth.
- Reduced risk of mechanical complications (screw loosening, bridge fracture) over the long term.
- Very high long-term success rates in patients with sufficient bone.
Side-by-Side Comparison
- Number of implants: All-on-4 uses 4; All-on-6 uses 6.
- Bone graft requirement: All-on-4 typically avoids grafting; All-on-6 requires adequate existing bone.
- Surgical complexity: All-on-4 is less invasive overall; All-on-6 is slightly more extensive.
- Load distribution: All-on-4 provides good support; All-on-6 spreads forces over a broader base.
- Bruxism suitability: All-on-4 requires careful evaluation; All-on-6 is generally preferred.
- Same-day temporary bridge: Possible with both, subject to clinical conditions and surgeon assessment.
- Relative cost: All-on-4 is typically less expensive; All-on-6 carries a higher fee due to additional implants and components.
Cost Considerations
The total investment for either system depends on several variables: the number of implants, the choice of prosthetic material (acrylic hybrid vs. full-contour zirconia), whether preparatory procedures are needed, and laboratory fees. As a general principle, All-on-6 costs more than All-on-4 because of the two additional implants and the corresponding abutments and prosthetic components.
That said, the "cheaper" option is not always the right one — placing All-on-4 in a patient who genuinely needs the load distribution of All-on-6 can lead to mechanical complications and higher remediation costs over time. A proper diagnostic work-up is the best investment.
The Treatment Journey: What to Expect
Both All-on-4 and All-on-6 follow a similar sequence:
- Comprehensive clinical examination, CBCT scan, and digital treatment planning
- Any necessary preparatory procedures (extractions, limited bone grafting)
- Implant placement surgery under local anaesthesia (sedation available on request)
- Fitting of the temporary fixed bridge the same day or shortly after
- Osseointegration monitoring over 3 to 6 months
- Fabrication and fitting of the definitive zirconia bridge
- Twice-yearly professional maintenance appointments
For detailed aftercare instructions following your implant procedure, read our guide on Dental Implant Aftercare: 10 Golden Rules.
Which Option Is Right for You?
The answer depends on your bone anatomy (assessed by CBCT), your bite characteristics, any parafunctional habits such as bruxism, and your personal priorities around timeline and budget. No online article can substitute for a hands-on clinical assessment.
At DUODENT in Atasehir, Istanbul, Dr. Dt. Ayse Saatman Yildiz will review your CBCT images and provide a clear, personalised recommendation. To discover the full range of implant treatments we offer, visit our treatments page. To book a consultation, use our contact page.
Frequently Asked Questions
What is the main difference between All-on-4 and All-on-6?
All-on-4 uses four implants with angled posterior fixtures, making it suitable for patients with reduced bone volume. All-on-6 uses six implants for broader load distribution and is preferred when bone is adequate and maximum stability is the goal.
Do I need a bone graft before All-on-4?
In most cases, no. The angulated posterior implants are specifically designed to avoid the sinus and reach denser bone without grafting. However, your CBCT scan will confirm whether any additional bone preparation is required.
Can I get teeth the same day as the surgery?
In many cases, yes — a temporary fixed bridge can be attached on the day of implant placement ("immediate loading"). The final permanent bridge is fitted after osseointegration is complete, typically 3 to 6 months later.
Is All-on-4 or All-on-6 better for bruxism patients?
Bruxism generates forces that can stress individual implants more heavily. For this reason, All-on-6 is generally preferred for bruxism patients because the load is spread across more implants. A night guard is also recommended to protect the prosthesis.
This article is for informational purposes only and does not constitute medical advice. Please consult a qualified dental professional for guidance specific to your clinical situation.