Rehabilitation of the Atrophic Edentulous Maxilla: A Retrospective Cohort Study Comparing Survival of Delayed-Loaded Implants in Grafted Bone Versus Immediately Loaded Implants in Native Bone.

OBJECTIVES

This retrospective cohort study aimed to assess the survival rate of implants placed in grafted edentulous maxillary arches following a delayed loading protocol versus a graftless approach with an immediate loading protocol.

MATERIALS AND

METHODS

Eighty seven patients with atrophic edentulous maxillae were included in two groups: Group-1 (GG group, n = 155 implants): 26 patients that underwent maxillary bone grafting before treatment with axially placed delayed loading implants and provided with a fixed full-arch prostheses; Group-2 (GL group; n = 244 implants): 61 patients who received axial and tilted implants without bone augmentation followed by an immediately loaded fixed full-arch prostheses. Patients were followed up for up to 10 years. Kaplan-Meier and Mantel-Cox analyses were performed to determine implant survival rates, and a Cox hazards model was run to assess the influence of patient, implant, and prosthesis-based covariates.

RESULTS

There were no significant differences in implant failure rates between the two treatment groups (p = 0.298). Five implant failures were observed in Group-1 (GG group) and four failures were observed in Group-2 (GL group) (N = 9). Survival rate was 96.8% and 98.4% in the GG and GL groups, respectively. No significant association between patient and implant-based covariates and implant failure was observed in both groups; however, a significant association was observed regarding the nature of the opposing arch (p = 0.019).

CONCLUSION

Immediately loaded implants placed in maxillary native bone show statistically similar survival rates compared to implants placed in grafted bone following a delayed loading. The nature of the opposing arch may negatively influence the survival rate of dental implants.

CLINICAL SIGNIFICANCE: For atrophic edentulous maxillae, both grafted and graftless approach may represent a viable treatment modality in the long term.