ZYGOMA ANATOMY GUIDED APPROACH
THE ZAGA PHILOSOPHY
ZAGA is much more than just a method, it is a philosophy of how we work with patient well-being as one of its core principles. The individual characteristics and needs of each patient are the main elements considered when designing a treatment plan and deciding what materials or implants will be used.
By anchoring dental prosthesis to zygomatic implants, the ZAGA philosophy aims to achieve long-term success in treating severe maxillary atrophy. In addition to maximizing success, the ZAGA philosophy seeks to prevent complications instead of treating them. To obtain these objectives through a standardized process, the ZAGA philosophy develops and uses individual, contrasted and systemized action protocols.
After 10 years of experience with the original technique following their initial publication, for the first time, Dr. Aparicio and his group released and published several papers in top international academic journals in 2005 and 2006. These papers explained their new extra-sinus (or extra-maxillary) technique for placing zygomatic implants through the exterior maxillary lateral wall, avoiding the opening through the palate, as proposed by the original technique. The objective of the extra-sinus technique was to avoid two disadvantages of the original method: sinus complications and bulky prostheses. Furthermore, during this time, the concept of “immediate loading” was introduced, a concept that was taken from regular implants and applied to zygomatic implants. The first prosthesis could now be fixed and placed on the implant within 24 hours after the procedure. The protocols for the immediate loading of regular implants were established in 2002, after the first International Consensus of Immediate Loading, organized by Drs. Lars Sennerby, Bo Rangert and Carlos Aparicio.
In 2008 and 2009, Dr. Aparicio and his group published further results three years after their new extra-maxillary technique was introduced, noting that this method of placing zygomatic implants effectively reduced oro-antral communication-related sinus infections. They also noted that this technique improved the prostheses, a result that would later be confirmed by other authors such as Migliorança R.M., Malo P. and Corvello P.C. on the external immediate loading technique. However, Aparicio and his group also observed a new complication derived from the systematic application of the same technique on all patients: gum recession and the exposure of the zygomatic implant, creating a potential for bacterial infections.
HOW DID THE ZAGA METHOD BEGIN?
The ZAGA method originated from a need to offer patients with severe maxillary atrophy reliable, long-term solutions without the adverse effects of the original technique (sinus complications and bulky prostheses) and without the typical complications of exterior or extra-sinus techniques (gingival dehiscence and exposure of the zygomatic implant).
The ZAGA method was explained by Dr. Aparicio in his book “Zygomatic Implants. The Anatomy-Guided Approach” (ZAGA). After a series of surgical and anatomical studies with actual patients, Dr. Carlos Aparicio further developed the extra-maxillary technique for placing implants proposed by his own group in 2005. These contributions helped prevent gum recession and the presence of gaps in the gums surrounding the zygomatic implant. In 2011, based on a systematic classification of maxillary anatomy, he proposed a system for providing individualized treatment plans for each patient, known as ZAGA. The objective of these plans was to prevent the complications of previous techniques, which used similar surgical procedures for all patients.
ZAGA: A MINIMALLY-INVASIVE PROCEDURE?
The ZAGA method simplifies the procedures used by conventional zygomatic implant techniques: it preserves more bone, is faster and is more precise. Compared to traditional procedures or hip grafts, the ZAGA method allows for treatment to be minimally invasive.
This conservative approach preserves the integrity of the maxillary wall, a critical area where the zygomatic implant first enters. This prevents frequent sinus complications, common to other methods. Unlike traditional zygomatic implant techniques, the dental prosthesis used in the ZAGA method takes up a natural space in the mouth, as its dimensions are very similar to those of original teeth, which helps improve aesthetic aspects, maintenance and hygiene.
ZAGA ZYGOMATIC IMPLANTS
ZAGA zygomatic implants were developed from over 25 years of experience using zygomatic implants and in collaboration with a renowned team of engineers. The adaptability of their dimensions is far superior to what the market used to offer. Their placement requires a less invasive procedure and their composition is much more compatible with the body as it does not contain potentially harmful foreign chemical elements such as aluminum or vanadium. The shape of the implant is different as it adapts to the patient’s anatomy, preventing complications with its placement. Their texture and design also take the biology and function of the mouth’s structure into account. ZZCs use new ZAGA zygomatic implants.
THE ORIGINAL TECHNIQUE
The person that invented the zygomatic implant was professor and physician Per-Ingvar (P-I) Brånemark. The original surgical technique for placing implants in the zygomatic bone involved entering through the palate and passing through the maxillary sinus, a process that required a visual inspection by opening a “window” in the anterior maxillary sinus wall.
After inserting the implant, the gum was completely sealed, and a removable denture was attached. After a period of 6 months, the gum was opened again and the process for building a fixed prosthesis began. The total treatment time for this original technique took about 8 months. In 1993, Dr Aparicio − along with his mentor Dr P-I Brånemark, Professor Eugene Keller (Mayo Clinic, Rochester, USA) and Dr Jordi Olivé − published the first international article explaining how major maxillary bone loss could be repaired with zygomatic implants. The article was published in the scientific journal International Journal of Oral & Maxillofacial Implants.
In 1991, Dr Malevez gave the first surgical course on zygomatic implants, explaining the traditional technique described by Prof. P-I Brånemark. In the years that followed, many authors also published about the original technique, some of which include: Agliardi E.L., Al-Nawas B., Aparicio C., Bedrossian E., Bothur S., Boyes-Varley J.G., Chow J., Corvello P.C., Davo R., Duarte L.R., Espósito M., Fazard P., Higuchi K.W., Jensen O., Malevez C., Malo P., Migliorança R.M., Nkenke E., Parel S.M., Peñarrocha M., Pi Urgell J., Stella J.P. and Vrielinck L.
The overall conclusion of the results established in these publications is that zygomatic implants are generally stable, which is helpful to the longevity of the implant. However, an undetermined number of patients experienced late-onset infections, such as oro-antral communication problems. Another common problem that occurred during the initial phases of the surgical procedure was a bulky prosthesis, as they encroached upon the space of the tongue area and made it difficult to maintain oral hygiene.
THE ZAGA METHOD
The ZAGA method consists of a series of techniques, materials and action protocols used by the various professionals involved in treating severe maxillary bone atrophy. It takes a systematic approach to optimizing results by anchoring a fixed dental prosthesis to zygomatic implants. The ZAGA method is based on a systematic classification of the patients’ different anatomies. This classification helps identify the anatomy of each patient and therefore allows for treatment, its protocols and materials to adapt to it. This makes surgery less invasive and problematic, and more successful, drastically increasing the success rates of the treatment compared to traditional techniques.
In contrast to these traditional zygomatic implants techniques, the ZAGA method reduces the chances of sinus infections almost to zero. One of this method’s main objectives is to avoid problems or complications that derive from gum recession and implant exposure, common in extra-maxillary (or extra-sinus) methods. The dental prosthesis used with the ZAGA method occupies a space that is very similar to where a patient’s original teeth would normally be, which helps attain a more aesthetic and lasting structure. With the ZAGA method, fixed teeth can be placed in patients with severe maxillary atrophy in just one day, without the use of grafts or donor sites.
HOW IS THE PROCEDURE PERFORMED WITH THE ZAGA APPROACH?
The procedure for placing zygomatic implants using the ZAGA approach minimizes the need for a maxillary osteotomy by not having to open a “window” in the maxillary bone, as other techniques propose. This maximizes the area of contact the implant has with the zygomatic bone without having to make an unnecessary opening in the bone. Such a procedure not only involves greater precision in making such a perforation, but also allows for a solid seal of the sinus osteotomy and for enhanced implant stability.
With the ZAGA approach, the patient receives individualized treatment. The implant is placed through a minimally-invasive osteotomy, always preserving the palate. The zygomatic implant can be both inserted from the outside through the alveolar bone, which protects the sinus, as well as through a more intra-alveolar approach, depending on the patient’s maxillary anatomy. With this approach, more bone is conserved in the critical area near the alveolar ridge, the integrity of the Schneider membrane is maintained and the soft tissue around the implant head is healthier. The better the sealing is, the less chance there is of bacteria getting through.
In subsequent publications, the ZAGA method shows it has long-term, proven benefits over the original technique. The ZAGA approach offers a methodology that can systematize zygomatic implant placement and has proven to show successful results without long-term complications and with the added benefit of having more aesthetic and functional fixed teeth within 24 hours following the procedure.