The All-on-4 ™ concept

The goal of dentistry and particularly of modern implantology is to simplify the surgical and prosthetic procedures and especially to offer less invasive procedures.

In this context, a concept for the rehabilitation of a complete dental arch based on 4 implants was proposed. This is the concept All-on-4®. This technique has been scientifically approved and is now considered clinically reliable with over 18 years of decline.

In this article we will outline the principle of All-on-4®, the advantages but also the disadvantages inherent in this technique through a small historical overview that explains the development of this therapeutic approach.

Historical

In 1998, the first patient was successfully treated by Dr. P.Malo with the concept All-on-4®. However this concept was not new.

This technique is based on the principles approved in implantology since the 1970s because the Branemark teacher, dentist who introduced the concept of osseointegration, has published numerous articles in the 1970s (1977) with the successful rehabilitation of a full arch supported by a reduced number of implants.

However, this was actually the angulation of the posterior implants which led to the All-on-4® today tested by many clinicians simultaneously in the United States, Sweden, Portugal and South America in the 1990s it was also the period during which the immediate loading was documented.

Indeed, thanks to the development of these implants angulated technology has evolved to prevent certain anatomical structures in the upper and lower jaw, but also avoid areas with bone resorption usually located in the posterior especially for already patients with CAP.

Historical overview

1998	TREATMENT OF THE FIRST PATIENT WITH THE CONCEPT OF ALL-ON-4® BY DR. MALO
2004	Launching the concept of All-on-4® treatment by Nobel Biocare
2011	10 years of follow up to the mandible
2012	5 years of follow up to the maxilla
2015	34 clinical trials with 2000 patients
2016	> 100 000 patients treated with the concept of All-on-4®

Definition and principle

The concept of All-on-4® processing which means “all” (all) teething supported “one oven” (four) implants, owes its name to the same method of restoring a full arch maxillary or mandibular denture with a ten to twelve teeth (bridge) using four titanium implants.

It is a solution and prosthetic implant screwed and fixed without grafting using 4 or 6 implants that are placed in a specific position: vertical free implants in the anterior and two posterior implants inclined 30 to 45 ° relative to the plane of occlusion.

The head of the posterior implants approximately emerges at the position of the second premolars. This allows prosthetic restorations to 12 teeth.

This treatment has been developed to optimize the use of available bone in cases of atrophied jaws where the basal bone loss prevents them from getting dental implants (vertical) to conventional orientation. Indeed, this technique allows to take advantage of dense bone in the anterior part of the jaws but also to avoid the sinus cavities in the jaw and the nerve canal in the lower jaw.

For implementation to be successful, a careful analysis of bone structures must be done ideally a CBCT for analyzing the quantity and quality of available bone.

If this available bone quantity and quality or insufficient, recourse to 6 implants is required to distribute the forces over a larger number of implants.

This technique allows the charge and / or immediate aesthetics of the provisional prosthesis the same day of surgery.

The benefits of the treatment concept All-on-4®

This treatment option has several advantages:

minimally invasive solution. It allows the restoration of full arch with only 4 or 6 implants.
Treatment without the use of long bone grafting and sinus lift protocols. Thanks to the inclination of the posterior implants to use the available bone and avoid the anatomical structures, the operation is lighter.
Reducing complications inherent in bone regeneration techniques.
Reduction of postoperative and shortening healing time.
Immediate extraction-implantation (sunk teeth).
Maintenance of bone and prevention of resorption.
prosthetic restoration on the day of the intervention. This will quickly meet the patient for chewing, aesthetics, speech and self-esteem.
Immediate loading (fixed temporary bridge). It shortens the processing time and allows patients to resume normal chewing function after a few hours. It meets the needs of patients in a hurry, too busy or anxious.
reduced cost. This is the least expensive concept compared to traditional fixed solutions implant treatment complete edentulous patients or about to become so.

The disadvantages and limitations of All-on-4®

Like any surgical procedure, the indication should be well placed because it can not be applied to all patients with health problems.

It requires some experience of the practitioner because the protocol is complex and must be planned and executed with precision. Furthermore it requires a minimum quality and quantity of bone available.

What do the scientific studies?

This therapeutic solution was proven long term proving high survival rate with a decline of 18 to 13 years and the mandible to the maxilla.

A systematic review on the concept All-on-4® conducted by Penaloza and published in 2017 reported that the survival rate is 99.8% over 24 months.

Cumulative survival rates are high for both the edentulous maxillary and mandibular.

In the medium term, 3 to 4 years: 96.3 100%

In the long term, 5 to 10 years: from 94.8 to 98.0%

34 clinical studies were conducted with 2000 patients and over 9200 TiUnite implants placed up to 10 years of follow up to the mandible and maxilla for 5 years. They show stable marginal bone levels and healthy soft tissue for both sloped and axial implants.

Conclusion

The All-on-4 ™ concept is an innovative therapy using a reduced number of implants. Both implants inclined allow weight bearing and immediate aesthetic full dentures, scientifically and clinically proven technique. It is based on principles of implantology documented in the 1970s.

Hundreds of thousands of patients have been treated with this concept in the world which reinforces the fiablité of this technique and allows for more distance.