A new classification of the edentulous atrophic maxillae based on zygomatic implant surgery and immediate loading protocols

doi:10.12337/zgkqzzxzz.2025.06.002

Abstract

Abstract: Immediate loading in edentulous maxillae remains a clinical focus, particularly challenging in cases with moderate to severe atrophy. While the effectiveness of dental implants for immediate loading of the edentulous maxillae has been increasingly proven, accomplishing this in cases with inadequate bone volume is notably important and presents a significant challenge. Multiple methods have been proposed to achieve feasibility and safety for immediate loading of edentulous jaws, however, they can neither meet the complex situations of various clinical cases nor provide clear guidance for protocol selection in clinical practice. This article is based on the significant development of zygomatic implant surgery in recent years and proposes a new classification of the edentulous maxillae based on zygomatic implant surgery and corresponding immediate loading protocols. The classification and immediate loading protocols are as follows: 1. The bone volume in the bilateral second premolar area (5-5) is sufficient, and at least four conventional dental implants, including tilted implants, can be placed without bone augmentation to achieve immediate loading; 2. The bone volume in the first premolar area (4-4) on both sides is sufficient, and at least two conventional dental implants can be inserted without bone grafting. Immediate loading can be achieved by combining 2-4 conventional dental implants in the anterior area with zygomatic implants in both posterior regions; 3. There is insufficient bone volume in the second premolar area (5-5) on both sides, while the bone volume in the molar areas is sufficient, and at least one conventional dental implant can be placed on each molar side. Zygomatic implants are used in the anterior area on both sides, and conventional implants are used in the posterior areas to achieve immediate loading;4. Insufficient volume is observed in the full maxilla (7-7). Immediate loading can be achieved by quad zygomatic implant surgery. This classification and the corresponding immediate loading protocols aim to cover various complex clinical scenarios of edentulous maxillae, providing a reference and indication for the selection of immediate loading plans for these patients.

Key words: Zygomatic implant, Edentulous jaws, Immediate loading, Implant-supported restoration, Clinical decision-making

Wu Yiqun, Wang Feng, Tao Baoxin. A new classification of the edentulous atrophic maxillae based on zygomatic implant surgery and immediate loading protocols[J]. Chinese Journal of Oral Implantology, 2025, 30(3): 203-208.

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