BEFORE ALL ON 4: History and Evolution of Dental Implants
A professor by the name of Per-Ingvar Branemark discovered a process known as osseointegration in the 1950’s. This marked the advent of implant dentistry and the subsequent progression in the science which eventually led to the development of the All On 4 method in it’s current state today. The term osseointegration is scientific terminology for the process of titanium being fused or “integrated” with bone, and is a hybrid word derived from the Greek for ‘bone’ and the Latin for ‘becoming whole’.
Professor Branemark found that the human body accepts titanium as though it were it’s own natural substance, thus making dental implants possible. This discovery was soon followed by the first application of implants into a patient’s oral cavity in 1965. Interestingly, the procedure involved an entire dental arch replacement rather than just one single tooth implant. Typically a single tooth replacement towards the rear of the jaw would have been expected, but instead Professor Branemark performed a comprehensive oral rehabilitation using numerous fixtures or “implants”. Initially, the fundamental purpose of implants was to rehabilitate oral function, and the trend continued through the 1970’s and 80’s. At this stage, single tooth replacement was not the focus, rather, all studies and experimentation revolved around full arch cases. The developments during this era were to determine the future of dental implants and relied heavily on innovators taking risks and carefully selecting case subjects. It leaves one to wonder why full arch cases were the focus rather than single tooth replacement, given the evidence that single tooth implants had been proven to work.
The reasoning behind the full arch focus was based on risk-to-benefit ratio and fundamental biomechanics. By linking together multiple titanium fixtures for supporting prosthetic teeth, distinct physical advantages were observed. The distribution of functional pressure was more evenly shared across the jaw through the rigid cross-arch fixation and greater support for the replacement teeth was experienced. This resulted in far less pressure on each individual fixture, allowing the entirety of the prosthesis to easily integrate with the jaw bone. This is called a biomechanical advantage, and remains today as one of the founding principles of implant dentistry.
The risk-to-benefit ratio presented by the biomechanical advantage of multiple fixtures was made even more appealing by the significance of treating patients needing full arch tooth replacement. Patients suffering from tooth loss or debilitation from poorly functioning dentures were presented with the prospect of experiencing a total rehabilitation of oral function and thus being no longer categorized as edentulous “oral invalids.” The biomechanical advantage also meant greater overall success regardless of failure within individual fixtures.
Dental Implants are a proven and routine phenomenon, and osseointegration is now the the most widely researched topic within dentistry. In 2004 it was reported by the American Dental Association (ADA) that “the average survival rates of multiple implant designs placed in various clinical situations are more than 90%”. It was also reported that “a more predictable outcome” is afforded through implants than through alternative oral therapies. [Stanford C, Rubenstein J. Dental endosseous implants-an update. ADA Council on Scientific Affairs. Journal of the American Dental Association 2004; 135:92-95] Current statistics demonstrate that osseointegration success rates are between 97% and 98.5% — higher than those of all other dental procedures performed. However, is mere “survival” of titanium implants enough?
Watch Professor Banemark, founder of osseointegration, speaking at a dental convention in Sweden in 2012.
From “Implant Survival” to “Case Success”
The initial goals of implant therapy were oral function and implant survival. These criteria are no longer the only concerns, as oral health and aesthetics are now enjoying equal focus. “Survival” does not necessarily mean “success” just as “cosmetics” does not necessarily mean “aesthetics”.
In the vast majority of dental implant cases, osseointegration is successful and the titanium implants survive. Often, however, results are skewed by difficult cleaning protocols, poor aesthetics and a complicated treatment process. That’s why modern dental professionals, including the team at All On 4 are focused on “case success” rather than “implant survival.” This is done by re-imagining the idea of the procedure, elevating it from a simple dental implant process to the comprehensive treatment of the specific needs of the individual. Case success is now determined by the values of immediacy and high aesthetic appeal in addition to restoring oral function and overall quality of life.
The idea has been established that using less fixtures to support a full arch replacement sets the stage for higher probability of case success. The modern mindset of instant gratification is satisfied by the elimination of the implant healing phase and the practice of immediately loading the prosthesis. This is evolution in effect, based on the principles outlined below.
1. Less is More
In previous decades, anywhere from six to 12 implants were used per jaw to support the prosthesis. This was because it was thought that if one or two implants failed, others would be in place to continue to provide support. It was later discovered that implant failure was most often due to poor hygiene resulting from the difficulty patients had in cleaning the fixtures. Less fixtures means less problems in locating the fixtures and cleaning them.
This cleaning difficulty is due to the submerged profile of the implants within the jaw, especially once the prosthesis is attached. Poor cleaning around the gum interfaces leads to infection and the potential failure of the implant. It’s simple: the less implants there are, the less implants can fail.
The All On 4 procedure uses two implants in the back and two in the front, creating a simpler dynamic when locating and cleaning. Once hygiene becomes more effective, the implant success rate improves.
Sometimes the forces at play during oral function are beset with certain imbalances which can create strain on the implant system. Patients who grind their teeth, bite with heavy force or have a thinning jawbone may require additional implants for prosthetic success.
2. The Evolution of All On 4 Plus Relied on the Angular Implant Position
The number one distinguishing feature of the All On 4 treatment is the placement of the back implants at a 45 degree angle.
Angulated implants allow clinicians to avoid the anatomical limitations found in the back of the upper jaw and to work around bone deficient areas. Often times the angular arrangement of the back implants creates a situation where there is only enough room for a total of four implants to support the entire prosthesis.
Dr. Branemark was aware of the possibility of supporting a full prosthesis with only four implants as early as the 1970’s, and published numerous articles while osseointegration was still in its infancy. It was not until the use of angulated implants, however, that the idea became widely accepted as practical, leading to today’s All-On-4 method.
The 1990’s saw worldwide experimentation among dental clinicians in Sweden, Portugal, South America and the United States, however the practice did not take off in Australia until 2005 — and is now available in New Zealand. Dr. Alex Fibishenko was one of the first Australian practitioners to use angular implants, and made innovative modifications to the procedure to enhance patient experience and overall outcome.
Initially, this practice did not win popular favour among opinion leaders in Australia, however Dr. Fibishenko’s surgical and restorative innovations provided much needed contingency. The streamlined process led to a rise in popularity as it became clear that the procedure was highly effective.
3. The Case Made by the Space
Previously, the practice of building back atrophied bone though bone grafts was the accepted method for creating a sturdy bed for implants. It has been discovered, however, that although predictably reliable in function, this method often leaves something to be desired visually due to poor alignment of the jaw and gums.
It was also discovered that the building up of jaw bone leaves less room for the prosthetic teeth to function while compromising the strength of the bridge once it was fitted to the implants.
The All-On-4 Plus treatment achieves a high level of aesthetic success by re-shaping the jaw bone after the teeth are removed. The benefits of this are numerous:
- A flatter interface beneath the bridge makes for easier cleaning
- Aesthetic Gum Replacement is made possible by the fact that the gums become part of the prosthesis, allowing dental clinicians to have intricate control over the choreography of the gums and the balanced appearance of the teeth
- More durable restorations, improved comfort and better aesthetics are made possible by the creation of more space in the mouth.
4. Instant Replacement of Teeth
Previously, dental implants were achieved through a procedure consisting of two stages. First, the implants were inserted into the jawbone and then required a 4 to 6 month healing period. After healing, the prosthesis were then affixed into the implants.
During the healing period, patients had to wear dentures which were later found to place unnecessary pressure onto the new implants. This disturbed the titanium’s integration into the bone and prolonged the overall procedure.
5. Education and Training
Dental implant work is a highly-specialized field and requires that surgeons possess a highly intimate knowledge of the restorative requirements. The surgical clinicians at the All-On-4 Clinic are highly-trained and experienced in the two disciplines necessary for this work: Oral Surgery and Restorative Dentistry. This allows the patient to have every stage of treatment performed in one clinic location.
Zygoma Plus and All-On-4 Plus are advanced treatments, and require that clinicians attain experience gradually. The goal is not to merely undo damage, but to rehabilitate function and restore aesthetic appeal and quality of life.
Sound treatment planning is the most important aspect of dental implants, followed by cross-disciplinary knowledge and manual dexterity. When considering implants, it is important to discuss your options with your regular dentist before electing to become a patient at one of the All-On-4 clinics. He or she may decide to become better familiarized with the latest practices and procedures through continuing education and training at one of the All-On-4 Clinics in New Zealand.
A comprehensive vision of what dental implants mean to patients is key to our success at All-On-4. We do not see this merely in terms of implants and prosthetic teeth, but as a restorative process allowing a patient to function normally while being proud of a beautiful smile. Synchronising predictability and practicality with possibility determines the quality of our treatment planning.
For more information about All-On-4 and Dental Implants, or to determine your eligibility for these procedures, call us here 1300 255 664 (1300 ALL ON 4).