Clinical outcomes of full-arch immediate fixed prostheses supported by two axial and
two tilted implants: A retrospective cohort study with 12-15 years of follow-up
PurposeTo retrospectively assess clinical and radiographic outcomes of immediately
loaded full-arch fixed prostheses supported by axial and tilted implants up to 15
years of function. Materials and MethodsPatients with one completely edentulous arch
received an immediate full-arch fixed prosthesis supported by two anterior axial and
two posterior tilted implants. Definitive prosthesis consisting of a CAD-CAM titanium
framework and acrylic teeth was delivered 6 months later. Patients were regularly
followed to assess clinical parameters and marginal bone level (MBL) change. Multilevel
regression analysis was performed to investigate factors affecting implant failure
and MBL. ResultsSix hundred ninety-two implants were placed in 72 maxillae and 101
mandibles. Seven maxillary implants (5 axial and 2 tilted) in 6 patients and 12 mandibular
implants (6 axial and 6 tilted) in 5 patients failed. 15-year cumulative implant survival
was 97.51% and 96.91% in maxilla and mandible, respectively (p = .64). After 10 years,
the difference in MBL between axial and tilted implants was not significant in the
maxilla (p = .47, 65 patients), while it was in the mandible (p < .001, 80 patients).
Significant higher bone loss was reported in the mandible at both 5- and 10-year follow-up
(p < .001 and p = .004, respectively). Mixed-effect multilevel linear regression evidenced
a correlation between arch and bone loss at 5- and 10-year follow-up, while no correlation
was found with age, gender, smoking, diabetes, and history of periodontal disease.
ConclusionThis long-term study suggests that the present technique can be considered
a viable treatment modality for the immediate rehabilitation of both maxilla and mandible.