Aim The purpose of the present research was to assess the prognosis of immediately loading implants on all on 4 concept in practicing implantologists. Methodology A total of 126 patients with 136 All-on-4 restorations supported by 544 implants were included in this retrospective cohort study. The observation period was 1 year. In 42 cases, a PR was placed initially and replaced by a DR 3 months later. In 94 cases, a DR was placed immediately. Biological, technical, and severe (loss of an implant or PR/DR) complications associated with PRs and DRs were compared. The absence of a serious complication was considered a success. Results A total of 27 patients were affected by 33 complications, 19 biological (2 PR and 17 DR) and 14 technical (6 in PR and 8 in DR) in the first 3 months. Implant survival rate was 98.2% (99.4% PR and 97.6 DR), and restoration survival rate was 94.4% (97.6% PR and 92.6% DR). After 3 months, ten complications occurred in six patients within 1 year. Conclusion PRs and DRs showed comparable complication rates during the observation period

All-on-4, Definite, Fixed denture, Implant, Provisional, Restoration