All-on-4®: The Implant Revolution for a Fixed, Full Smile

Losing all your teeth or facing imminent full-mouth extraction is a daunting prospect. Wearing a traditional removable denture, with its potential discomfort, instability, and limitations, is not always the ideal solution. Fortunately, dental implantology has made giant leaps, offering high-performance, fixed alternatives. Among them, the All-on-4® technique stands out as a revolutionary solution. It allows for the replacement of an entire arch of teeth (upper or lower jaw) with a fixed prosthesis screwed onto just four dental implants. Discover everything you need to know about this innovative concept in this comprehensive 2025 guide.

The All-on-4® Concept Explained

The All-on-4® concept, developed by Dr. Paulo Maló in collaboration with Nobel Biocare in the late 1990s, is a full-arch oral rehabilitation approach for patients who are completely edentulous or soon to be. Its fundamental principle is based on the strategic use of four dental implants to support a complete fixed prosthesis (a bridge of 10 to 12, or even 14 teeth) on a single arch.

The unique feature lies in the placement of the implants:

• Two anterior implants are generally placed vertically in the front part of the jaw, where the bone is often denser.
• Two posterior implants are tilted (typically up to 45 degrees) to increase the contact surface with the bone, avoid important anatomical structures (like the maxillary sinuses or the mandibular nerve), and allow for the use of longer implants in sometimes reduced bone volumes. This angulation also allows for better distribution of chewing forces.

This ingenious configuration often makes it possible to avoid complex and costly bone grafting procedures, making the treatment faster, less invasive, and accessible to a larger number of patients. Many patients can receive a temporary fixed prosthesis on the same day as the surgery (immediate loading).

Who is a Candidate for the All-on-4® Treatment?

The All-on-4 treatment is an excellent option for a wide range of patients, including:

• Individuals who are completely edentulous on one or both arches.
• People whose remaining teeth are severely damaged, loose, infected, and cannot be saved, requiring full extractions.
• Wearers of removable dentures who are dissatisfied with their comfort, stability, or chewing efficiency and desire a fixed solution.
• Patients with moderate bone loss, where the All-on-4 technique, thanks to the tilting of the posterior implants, can help avoid a bone graft.
• Patients looking for a fast and effective full-arch rehabilitation solution, with the possibility of immediate loading (temporary fixed teeth on the day of surgery).
• Patients in good general health. Certain medical conditions (uncontrolled diabetes, severe autoimmune diseases, IV bisphosphonate treatments) may be relative contraindications or require special precautions. Heavy smoking can compromise success.

A thorough evaluation by a dentist experienced in implantology is essential to determine if you are a good candidate.

The All-on-4® Procedure: Key Steps

Although each case is unique, the All-on-4 procedure generally follows a well-established protocol:

1. Initial Consultation and In-depth Planning:
   • Comprehensive clinical examination of the mouth.
   • Radiographic assessment: panoramic X-ray and 3D CT scan are essential to evaluate bone quantity and quality, and the position of nerves and sinuses.
   • Impressions or intraoral scans to create study models.
   • Discussion of the patient's expectations, presentation of the treatment plan, alternatives, and a detailed quote.
   • Computer-assisted surgical planning (often with a surgical guide for optimal precision).
2. Surgical Phase (usually 2 to 4 hours per arch):
   • Performed under local anesthesia, conscious sedation, or general anesthesia, depending on the case and patient preference.
   • Extraction of remaining teeth (if necessary).
   • Preparation of the bone site and placement of the four dental implants according to the plan.
   • Suturing of the gums.
3. Placement of the Temporary Fixed Prosthesis (Immediate Loading):
   • In most cases, a temporary resin prosthesis, fabricated beforehand, is screwed onto the implants on the same day as the surgery or within 24-48 hours.
   • This prosthesis allows the patient to leave with fixed teeth, immediately restoring aesthetics and some chewing function (soft foods initially).
4. Healing and Osseointegration Phase (3 to 6 months, or more):
   • The period during which the implants fuse solidly with the bone.
   • Regular follow-ups with the dentist. Strict hygiene instructions and a modified diet (soft, then gradually firmer) are required.
5. Fabrication and Placement of the Final Prosthesis:
   • Once osseointegration is confirmed, new high-precision impressions are taken.
   • The final custom prosthesis (full-arch bridge) is fabricated in a lab using the chosen material (see below).
   • Try-in appointments to validate the fit, bite, and aesthetics.
   • The final prosthesis is screwed onto the implants.

What Materials Are Used for the Final All-on-4® Prosthesis?

The final All-on-4 prosthesis is a full-arch bridge that can be made from different materials, influencing aesthetics, durability, and cost:

• Reinforced Acrylic Resin Prosthesis (with or without a metal framework):
  • Pros: The most economical option for the final prosthesis, lighter, easy to repair or modify.
  • Cons: Less durable than ceramic (resin teeth wear faster, can stain), aesthetics are good but less natural than ceramic. Estimated lifespan: 5 to 10 years before major relining/refurbishment.
• Hybrid Prosthesis (Metal Framework with high-end composite or acrylic teeth):
  • Pros: Good compromise between cost, strength (thanks to the framework), and improved aesthetics compared to simple resin. Composite teeth are more wear-resistant and aesthetic.
  • Cons: Less durable and aesthetic than ceramic. Estimated lifespan: 7 to 15 years.
• Zirconia Prosthesis (Monolithic or Layered):
  • Pros: A premium material for its biocompatibility, very high strength (especially monolithic), and excellent aesthetics (especially when layered with cosmetic porcelain). No metal.
  • Cons: The most expensive option. Can be a bit "harder" on the opposing arch if it consists of natural teeth.

The choice of material will be discussed with your dentist based on your aesthetic expectations, habits (like teeth grinding), and budget. The temporary prosthesis is almost always made of resin.

The Significant Advantages of the All-on-4® Technique

The All-on-4 concept offers numerous benefits compared to traditional full-arch solutions:

• Fixed and Stable Solution: Eliminates the drawbacks of removable dentures (movement, irritation, adhesives).
• Reduced Number of Implants: Only 4 implants per arch, reducing surgical complexity and cost compared to implanting tooth-by-tooth.
• Often Avoids Bone Grafting: Thanks to the tilting of the posterior implants.
• Frequent Immediate Loading: Possibility of having temporary fixed teeth on the day of surgery.
• Rapid Restoration of Function and Aesthetics: Significant improvement in quality of life.
• Chewing Comfort: Allows for eating a wider variety of foods with ease.
• Simplified Maintenance:Hygiene is similar to that for natural teeth (brushing, interdental brushes, water flosser).
• Preservation of Bone: Implants stimulate the bone and help prevent its resorption.
• Durability: Implants can last a lifetime with good care; the prosthesis is designed to last many years.
• Positive Psychological Impact: Regaining a fixed, natural-looking smile boosts self-confidence.

Potential Disadvantages and Risks of All-on-4®

Like any procedure, the All-on-4 has some drawbacks and risks to consider:

• Significant Initial Cost: Although often less expensive than a full rehabilitation with more implants, it is still a major investment.
• Surgical Procedure: Carries inherent risks (infection, bruising, post-operative pain, very rarely nerve injury).
• Implant Failure: Although rare (success rates are over 95%), an implant may fail to integrate with the bone.
• Complexity of Prosthesis Repairs: If the prosthesis (especially ceramic or zirconia) fractures, its repair can be more complex and costly than with a denture.
• Need for Rigorous Hygiene: Essential to prevent peri-implantitis (inflammation around the implants).
• Adaptation Period: An adjustment period is needed to get used to the new prosthesis (speech, sensations).

What is the Cost of an All-on-4® Treatment in the US?

The cost of a full-arch All-on-4 rehabilitation in the US can vary considerably, generally ranging from $20,000 to $50,000 or more per arch. This wide range is explained by several factors:

• The dentist's and surgical team's fees: Experience, reputation, complexity of the case.
• The type and brand of implants used.
• The material of the final prosthesis: Resin is the least expensive, while zirconia is the most costly.
• Dental laboratory fees.
• The need for additional procedures: Preliminary tooth extractions, type of anesthesia.
• The geographic location of the clinic.

It is crucial to obtain a detailed and personalized quote before starting treatment. Many dental offices offer third-party financing options to help manage the investment.

Regarding insurance, coverage for a procedure like All-on-4 varies greatly. It is considered a major procedure, and many plans will cover a portion of the costs (e.g., extractions, the prosthesis itself) up to the plan's annual maximum. The implants themselves may or may not be covered. Submitting a pre-treatment authorization to your insurance provider is essential to understand your benefits.

All-on-4® Abroad: Is It a Good Option?

Faced with high domestic costs, some patients look to clinics abroad (e.g., Mexico, Costa Rica) for All-on-4 treatments. The savings can appear substantial.

Precautions to take:

• Thoroughly research the clinic and the qualifications of the practitioners.
• Verify the brands of implants and prosthesis materials used.
• Inquire about warranties and post-operative follow-up (essential in case of complications).
• Factor in travel, accommodation, and time costs.
• Language barriers can be an issue.
• Your U.S. dental insurance will typically not cover treatments performed outside the country.

Our Take on the All-on-4® Concept

The All-on-4 technique represents a major advancement and an excellent solution for the fixed full-arch rehabilitation of edentulous patients. When indicated and performed by an experienced team, it delivers highly satisfactory functional and aesthetic results with a significant impact on quality of life.

Although the initial investment is substantial, the long-term benefits in terms of comfort, self-confidence, and oral health can largely justify it, especially when compared to the cumulative cost and limitations of less effective solutions over many years. The choice of the final prosthesis material is a key factor for long-term durability and aesthetics.

Frequently Asked Questions About All-on-4®

What is the difference between All-on-4 and All-on-6?

The principle is the same: a full fixed prosthesis on implants. All-on-6 uses six implants per arch instead of four. It is sometimes preferred when bone density is lower or to provide additional support for the prosthesis, particularly in the upper jaw. The choice between All-on-4 and All-on-6 is made by the surgeon after analyzing your specific case and bone quality.

Is the All-on-4® procedure painful?

The surgery itself is performed under anesthesia (local, sedation, or general), so it is painless. Post-operative pain, swelling, or bruising may occur in the following days but are generally well-managed with prescribed pain relievers and anti-inflammatories. Most patients report manageable discomfort.

What is the lifespan of All-on-4® implants and prosthesis?

The dental implants themselves, if well-maintained and in the absence of complications (like peri-implantitis), have a very high success rate and can last a lifetime. The prosthesis screwed onto them has a variable lifespan depending on the material:

• Acrylic/Hybrid: 5 to 15 years before needing refurbishment or replacement of the teeth.
• Zirconia: 15 to 20 years or more, but may require repairs in case of chipping.

Periodically, the screws may need to be tightened or small wear-and-tear components replaced.

Can you eat everything with an All-on-4® prosthesis?

Yes, once the healing phase is complete and the final prosthesis is in place, you should be able to eat a normal, varied diet, including harder foods you may not have been able to eat with dentures. There is an adaptation period, and it's wise to avoid repeatedly biting on extremely hard items.

How long is the recovery period after an All-on-4®?

The initial recovery from surgery (pain, swelling) lasts a few days to a week. The full osseointegration of the implants takes 3 to 6 months. During this period, a soft to moderate diet is recommended to avoid overloading the implants. Impeccable oral hygiene is crucial.

How do you clean an All-on-4® prosthesis?

Maintenance is similar to that of natural teeth but requires special attention to the areas under the prosthesis and around the implants: careful brushing 2-3 times a day, use of specific interdental brushes, superfloss, or a water flosser to clean under the bridge. Regular professional cleanings and check-ups (about every 6 months) are essential.

If you are looking for a fixed and durable solution to replace all your teeth, the All-on-4® concept is well worth your consideration. Discuss it with a qualified implant dentist to find out if this technique is right for your situation and to get a personalized treatment plan.