Purpose: This study aimed to identify the technical complications associated with maxillary
complete-arch implant-supported fixed prostheses (ISFPs) and to evaluate the survival rates of
both implants and prostheses. Additionally, we sought to analyze the impact of the presence of
cantilevers, the type of prosthetic abutment, and the number of implants on the occurrence of
complications. Materials and Methods: Data were obtained from standardized clinical
assessments carried out in a single appointment by two calibrated professionals using
information from dental records. Results: The sample consisted of 64 patients rehabilitated with
ISFPs classified as hybrid prostheses (metal-resin). The survival rate for implants was 98.6%
after 1 to 12 years (5.2 years ± 36.6 months) and was 100% for the prostheses after a follow-up
period of 12 to 144 months (mean 48.1 ± 33.94 months). The most frequent complications were
occlusal wear (82.8% of patients) and loosening of prosthetic screws (16.6%) and abutments
(8.1%). Screw loosening frequency was significantly greater in 30-degree abutments compared
with straight abutments (P=0.008), but no significant difference was found between 17-degree
and 30-degree abutments. Prostheses with a higher occurrence of screw loosening had a greater
average CL/AP spread ratios (0.9 0.5). In addition, abutments installed on distal implants were
more likely to loosen (P<0.001). The absence of mutually protected occlusion did not
significantly influence the loosening of screws and prosthetic abutments. Conclusions: Implantsupported
fixed maxillary complete-arch rehabilitations have high survival rates but are subject
to technical complications.
Keywords: dental implants, maxillary edentulism, mechanical outcomes, screw loosening, follow-up