Retrospective Evaluation of Zygomatic Implant Therapy in Patients With Severe Tooth Agenesis and Maxillary Deficiencies: Clinical Outcomes and Safety up to 15 Years of Follow‐Up

PURPOSE: This retrospective study analyzed the clinical data of 27 patients with severe tooth agenesis who underwent zygomatic implants (ZIs) over the past 15 years, with an aim of evaluating the efficacy and safety of ZIs in patients with severe oligodontia and anodontia. MATERIALS AND METHODS: Patients who were diagnosed with severe oligodontia or anodontia and treated with ZI were included. All the patients received comprehensive preoperative assessments, including radiographic imaging, genetic testing, and multidisciplinary consultations to develop customized treatment plans. The treatment strategies primarily involved extensive bone grafting combined with multiple conventional implants (CIs) and a single ZI approach or the Quad Zygoma approach. Postoperative rehabilitation involved immediate or delayed loading with provisional prostheses, followed by definitive full-arch implant-supported restorations. RESULTS: Twenty-seven patients with 20 patients exhibiting syndromes, aged 18-37 years (mean age 22.63), were enrolled. A total of 85 ZIs and 42 CIs were placed in the maxilla. All the ZIs achieved successful osseointegration, yielding an early survival rate of 100%. The crude survival rates of ZIs and CIs were 98.5% (84/85) and 76.19% (32/42) at the implant level and 96.3% (26/27) and 64.71% (11/17) at the patient level, respectively, with a mean follow-up of 55.07 months (range: 13.27-179.2 months). The main complications associated with ZIs included maxillary sinus opacification and peri-implant soft-tissue recession. CONCLUSIONS: ZIs could be a treatment option for patients with severe oligodontia and anodontia. This study may support the feasibility and favorable outcomes of ZIs in the management of severe tooth agenesis.