Comparative analysis of the frequency and nature of prosthetic and surgical complications associated with zygomatic, pterygomaxillary (pterygoid), and conventional dental implants: A Systematic Review

Introduction. Rehabilitation of patients with severe maxillary atrophy can be performed using conventional implants (CI), zygomatic implants (ZI), and pterygomaxillary/pterygoid implants (PI); these strategies differ in biomechanics and complication profiles. The aim was to compare the frequency and nature of surgical, biological, and prosthetic complications associated with ZI, PI, and CI, and to summarize data on survival/success and marginal bone loss.
Materials and Methods. A PRISMA 2020–compliant systematic review. Searches were conducted in PubMed and eLibrary up to November 1, 2025. Inclusion criteria: adults undergoing implant placement in the maxilla; outcomes included implant/prosthesis survival, complications, and bone loss. Study designs: randomized controlled trials, prospective/retrospective cohort studies, and case series. Risk of bias was assessed using RoB 2.0/NOS/NIH tools. Due to substantial heterogeneity, a narrative synthesis was performed.
Results. Nineteen studies were included. For CI, 5-year survival in RCTs was ~99–100% (4 vs 6 supports; no differences in bone loss), whereas at 10–20 years survival decreased to ~93% and ~87%, respectively; short/ultrashort implants were not inferior to sinus augmentation protocols in terms of survival while being less invasive. Technical complications were more frequent with four supports, particularly in bruxism. For ZI, medium- and long-term survival was ~94–98%; the complication profile was shifted toward sinus-related and soft-tissue events, and chronic sinusitis occurred less often with extra-/extramaxillary trajectories than with an intra-sinus approach. For PI, 1-year survival/success ranged from ~88–98% depending on the criteria used; key risks included nerve injury, rare implant fractures, and prosthetic failures; first-year marginal bone loss served as an indicator of an unfavorable course; better stability was observed in D2 bone and with bicortical fixation.