Purpose: To review the evidence from the clinical outcomes of immediately loaded implants with fixed prostheses in edentulous maxillae.

Materials and methods: An electronic search was performed in PubMed/MEDLINE, Embase, and Cochrane to identify studies investigating the outcome of implants subjected to immediate loading with fixed dental prostheses in edentulous maxillae. Only clinical studies with more than 10 patients and a mean follow-up time of more than 12 months were included. Meta-analysis was utilized to compare the clinical outcomes between immediately loaded implants and conventionally loaded implants. For immediately loaded implants, a cumulative implant survival rate (ISR) was weighted by the duration of follow-up and number of implants. The weighted marginal bone loss (MBL) was also assessed.

Results: A total of 33 studies (16 retrospective studies and 17 prospective studies) were included, which involved 2,635 patients and 12,480 implants. Meta-analysis did not reveal a significant difference of ISR or MBL between the two loading groups. For immediately loaded implants, the weighted cumulative ISR was 95.53% (median: 97.50%) with a mean follow-up of 46.07 months (SD: 30.92). Fourteen studies reported on the MBL of implants, and the mean MBL was 1.19 mm (SD: 0.88) with a mean period of 57.70 months (SD: 32.56). The results should be interpreted with caution due to the lack of randomized controlled trials (RCTs) and the heterogeneity of the data.

Conclusion: Despite the lack of RCTs, immediate implant loading with a fixed prosthesis in the edentulous maxilla seems to be a reliable treatment alternative with a high ISR, when appropriate inclusion/exclusion criteria are followed.