Immediate Loading of Tilted and Axial Posterior Implants in the Edentulous Maxillary Arch: A Retrospective Comparison of 5-Year Outcomes

Purpose: The purpose of this study was to retrospectively compare long-term outcomes for immediately loaded tilted and axial implants placed in the posterior region of the edentulous maxillary arch. Materials and Methods: Data obtained from a 5-year prospective study designed to assess clinical outcomes following immediate loading of implants with screw-retained fixed restorations in the edentulous maxillary arch were retrospectively reviewed. Where insufficient alveolar bone was available for axial placement of the posterior-most implant on each side of the arch, tilted placement was employed. Implant survival and marginal bone level changes for these tilted and axial posterior implants were compared. Results: Fifty-one subjects received 64 tilted and 38 axial posterior implants. Forty subjects with 53 tilted and 34 axial posterior implants returned for follow-up after 5 years. Five tilted and seven axial implants failed, representing an 89% and 86% survival proportion, respectively. The mean marginal bone loss was 0.79 (SD: 1.42) mm for tilted implants and 0.14 (SD: 0.34) mm for axial implants. The differences in survival proportions and marginal bone loss between axial and tilted implants were not statistically significant. Conclusion: Predictable long-term implant rehabilitation may be achieved in the edentulous maxillary arch using posterior tilted implants in combination with immediate loading.