Definition and Procedure of All-on-4
- All-on-4 is a dental rehabilitation technique for edentulous or dentate patients.
- It involves placing four implants in the anterior maxilla where bone density is higher.
- The implants support a fixed prosthesis with 10 to 14 teeth.
- The procedure can be done immediately, typically within 24 hours of surgery.
- The All-On-Bar concept adds a milled titanium bar structure to the dental implants for better stability and longevity.
Evolution and Advantages of All-on-4
- The All-On-4 technique has evolved over time and is not an invention.
- It has been documented since 1977 for the use of four dental implants.
- Angulated implants have been used since 1990 to overcome bony deficiencies.
- Immediate loading of implants has also been documented since 1990.
- All-on-4 provides a permanent, same-day replacement for missing teeth.
Cost and Materials of All-on-4
- The cost of All-on-4 varies based on the prosthetic material used.
- Acrylic resin teeth over a titanium bar are cheaper, costing around $30K per arch/jaw in the US.
- Premium materials like Zirconia can result in a total cost between $36K to $40K per arch/jaw.
- A cone beam computed tomography (CBCT) scan is ideal for evaluating bone structure.
- The All-on-4 protocol requires at least four implants to be placed in a jaw.
Research and Efficacy of All-on-4
- Nobel Biocare funded studies by Portuguese dentist Paulo Maló to determine the efficacy of All-on-4.
- Various other clinicians around the world have also used this technique.
- Clinical studies have shown positive results for All-on-4 in terms of long-term success.
- The All-on-4 treatment concept has been found to be a cost-effective alternative to conventional implant techniques.
- Longitudinal studies have shown successful rehabilitation of completely edentulous mandibles using All-on-4.
References and Further Information
- Maló, Paulo; Rangert, Bo; Nobre, Miguel. All-on-Four immediate-function concept with Brånemark System implants for completely edentulous mandibles: a retrospective clinical study.
- Patzelt SB, Bahat O, Reynolds MA, Strub JR. The all-on-four treatment concept: a systematic review.
- Zhao X, DI P, Lin Y, Li JH, Qiu LX, Luo J, Cui HY. Implanting the edentulous jaws with All-on-4 immediate reconstruction: a preliminary clinical observation.
- Maló, Paulo; de Araújo Nobre, M; Lopes, A; Ferro, A; Botto, J. The All-on-4 treatment concept for the rehabilitation of the completely edentulous mandible: A longitudinal study with 10 to 18 years of follow-up.
- Branemark, Per-Ingvar. Osseointegrated implants in the treatment of the edentulous jaw: experience from a 10-year period.
The term All-on-4, also known as All‐on‐Four and All‐in‐Four, refers to 'all' teeth being supported 'on four' dental implants, a prosthodontics procedure for total rehabilitation of the edentulous (toothless) patient, or for patients with badly broken down teeth, decayed teeth, or compromised teeth due to gum disease. It consists of the rehabilitation of either edentulous or dentate maxilla and / or mandible with fixed prosthesis by placing four implants in the anterior maxilla, where bone density is higher. The four implants support a fixed prosthesis with 10 to 14 teeth, and it is placed immediately, typically within 24 hours of surgery.
The All-On-Bar solution, with the latest technology, computer aid design/Mill (cad/cam) the all-on-4 has evolved including the All-on-bar concept, which is adding a milled titanium bar structure to the dental implants which helps keep them working together. Protecting the implants from failures even after the hybrid bridge is broken. this concept helps the clinician provide a better long-lasting solution, instead of a conversion-denture which is a chair side repair and modified denture. The All-On-Bar reduces the appointments, eliminating the Denture Conversion Temporary by replacing it with a long lasting hybrid, some patients keep this option as their final due to a lower budget or because the space is limited for other final solutions.
Pmma or Denture teeth over the titanium bar wears out over time and need replacement, this is a controversial topic since the Pmma has the advantage of been shock absorbent. This helps the implants receive less stress during mastication forces but keeping a solid structure on the inside.many processionals think this is a better solution, keeping in mind that the bridge can be switched to a new one a few years after.
Implant manufacturer Nobel Biocare AB of Gothenburg, Sweden, was among the first to identify the evolution of the All-on-4 technique as a potential valid and cost-effective alternative to conventional implant techniques, and funded studies by Portuguese dentist Paulo Maló to determine the efficacy of this approach. During this time, this technique was also used by various other clinicians around the world.
All-on-4 is not an invention, but rather a treatment technique that has evolved over time, and has the following features:
The All-on-4 treatment concept is a prosthodontic procedure (i.e replacement of missing teeth) that provides a permanent, screw-retained, same-day replacement for the entire upper and / or lower set of teeth with a bridge or denture. The procedure is best for patients with significant tooth loss or decay, and for people whose bone loss in the jaw area prevents them from getting conventionally oriented (vertical) dental implants. Often, tooth loss is accompanied by loss of the jaw bone, which poses the problem of reconstruction of the jaw bone requiring bone grafting. The All-on-4 technique takes advantage of the dense bone that remains in the front part of the jaws, and by placing the two posterior implants on an angle to avoid the sinus cavities in the upper jaw and the nerve canal in the lower jaw. The cost of the All on 4 procedure varies based on the final prosthetic material. Acrylic resin teeth over titanium bar is substantially cheaper resulting in a total cost of around $30K per arch/jaw in the United States. Premium prosthetic materials like Zirconia can result in a total treatment cost between $36K to $40k per arch/jaw in the United States. For the implementation to be successful a careful analysis of the bone structure needs to be made. The most ideal way to evaluate the bone is by a cone beam computed tomography (CBCT) scan. The All-on-4 protocol is for at least four implants to be placed in a jaw. The back implants are typically angled approximately 30 to 45 degrees from the occlusion (biting plane). The implant is placed in front of the maxillary sinus in the upper jaw (maxilla), and in front of the mental nerve in the lower jaw (mandible). The head of the implant emerges in approximately the second premolar position. This will allow a molar tooth to be cantilevered posterior, resulting in a denture or bridge with approximately twelve teeth.
