ZAGA is an acronym that stands for Zygoma Anatomy-Guided Approach. This means that instead of basing treatment on an established surgical technique, the patient’s anatomy is used to help guide it. Therefore, instead of forcing the patient’s anatomy to adapt to our tools and processes, we adapt our own tools and processes to the patient’s anatomy.
THE BIOGRAPHY BEHIND THE ZAGA PHILOSOPHY
- The zygoma anatomy-guided approach (ZAGA) for rehabilitation of the atrophic maxilla. Aparicio, C., Olivo, A., de Paz, V. et al. Clin Dent Rev 6, 2 (2022).
- Reconstruction of the premaxilla with autogenous iliac bone in combination with osseointegrated implants. Aparicio C, Brånemark PI, Keller EE, Olive J. Int J Oral Maxillofac Implants 1993;8:61–67.
- A prospective clinical study on titanium implants in the zygomatic arch for prosthetic rehabilitation of the atrophic edentulous maxilla with a follow-up of 6 months to 5 years. Aparicio C, Ouazzani W, Garcia R, Arevalo X, Muela R, Fortes V. Clin Implant Dent Relat Res. 2006;8(3):114-22.
- Zygomatic implants: indications, techniques and outcomes, and the zygomatic success code. Aparicio C, Manresa C, Francisco K, Claros P, Alández J, González-Martín O, Albrektsson T. Periodontol 2000. 2014 Oct;66(1):41-58. doi: 10.1111/prd.12038. Review.
- The use of zygomatic implants for prosthetic rehabilitation of the severely resorbed maxilla. Aparicio C, Hatano N, Ouazzani W. Periodontol 2000, 2008;47:162–171.
- Zygomatic implants placed using the zygomatic anatomy-guided approach versus the classical technique: a proposed system to report rhinosinusitis diagnosis. Aparicio C, Manresa C, Francisco K, Aparicio A, Nunes J, Claros P, Potau JM. Clin Implant Dent Relat Res. 2014 Oct;16(5):627-42. doi: 10.1111/cid.12047. Epub 2013 Mar 6.
- The long-term use of zygomatic implants: a 10-year clinical and radiographic report. Aparicio C, Manresa C, Francisco K, Ouazzani W, Claros P, Potau JM, Aparicio A. Clin Implant Dent Relat Res. 2014 Jun;16(3):447-59. doi: 10.1111/cid.12007. Epub 2012 Oct 18.
- Immediate/Early loading of zygomatic implants: clinical experiences after 2 to 5 years of follow-up. Aparicio C, Ouazzani W, Aparicio A, Fortes V, Muela R, Pascual A, Codesal M, Barluenga N, Franch M. Clin Implant Dent Relat Res. 2010 May;12 Suppl 1:e77-82. doi: 10.1111/j.1708-8208.2008.00134.x. Epub 2008 Dec 3.
- A proposed classification for zygomatic implant patient based on the zygoma anatomy guided approach (ZAGA): a cross-sectional survey. Aparicio C. Eur J Oral Implantol. 2011 Autumn;4(3):269-75.
- Zygomatic Implants. The Anatomy-Guided Approach. Carlos Aparicio (Ed.) Quintessence Publishing Co Ltd, UK, 2012 , ISBN 978-1-85097-225-9
- On the Zygoma related rehabilitation. State of the art and proposed criteria for success. Carlos Aparicio. PhD Thesis, University of Barcelona 2013.
- Extrasinus zygomatic implants: three year experience from a new surgical approach for patients with pronounced buccal concavities in the edentulous maxilla. Aparicio C, Ouazzani W, Aparicio A, Fortes V, Muela R, Pascual A, Codesal M, Barluenga N, Manresa C, Franch M. Clin Implant Dent Relat Res. 2010 Mar;12(1):55-61. doi: 10.1111/j.1708-8208.2008.00130.x. Epub 2008 Dec 3.
- Validity and clinical significance of biomechanical testing of implant/bone interface. Aparicio C, Lang NP, Rangert B. Clin Oral Implants Res. 2006 Oct;17 Suppl 2:2-7. Review.
- Immediate/early loading of dental implants: a report from the Sociedad Española de Implantes World Congress consensus meeting in Barcelona, Spain, 2002. Aparicio C, Rangert B, Sennerby L. Clin Implant Dent Relat Res. 2003;5(1):57-60. Review.
- ORIS Criteria of success for the zygoma related rehabilitation: the (revisited) zygoma success code. Aparicio C, López-Piriz R, Albrektsson T. Int J Oral Maxillofac Implants 2020;35:366-378.
- Zygoma anatomy-guided approach “scarf graft” for prevention of soft tissue dehiscence around zygomatic implants: technical note. Aparicio C, Antonio S. Int J Oral Maxillofac Implants 2020;35:e21-e26.
- M PD, Jc BM, A FR, C A, D PO. Bone Regeneration and Soft Tissue Enhancement Around Zygomatic Implants: Retrospective Case Series. Materials (Basel). 2020 Mar 29;13(7):1577. doi: 10.3390/ma13071577. PMID: 32235372; PMCID: PMC7178084.
- Preoperative Evaluation and Treatment Planning. Zygomatic Implant Critical Zone (ZICZ) Location, C. Aparicio, R. López-Píriz, M. Peñarrocha, Atlas of the Oral and Maxillofacial Surgery Clinics, 2021, ISSN 1061-3315.
- The Zygoma Anatomy-Guided Approach for Placement of Zygomatic Implants, Carlos Aparicio, Waldemar D. Polido, Hooman M. Zarrinkelk, Atlas of the Oral and Maxillofacial Surgery Clinics, 2021, ISSN 1061-3315
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 the 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.
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 the 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 1998, 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.
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.
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.
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.