Second chances for smiles: a systematic review of implants in failed sites

Abstract

Aim

It has been proven that implants are predictable substitutes for replacing teeth. However, the effectiveness and survival of implants placed in sites previously affected by failure, as well as the optimal treatment strategies, remain poorly defined. This systematic review aimed to evaluate implant survival and peri-implant health in such cases, focusing on comparing immediate versus delayed implant placement and the role of augmentation.

Four electronic databases were systematically searched, and meta-analyses were conducted with subgroup analyses (PROSPERO CRD42024548610). Of 1,798 records identified, 24 studies met the inclusion criteria.

Results

The 1-year survival rate for implants placed as replacements was 96.7% (95% CI: 92.8–99.3%). No significant differences were found between immediate and delayed placement (P = 0.31), or between immediate and delayed augmentation (P = 0.85). Although implants with immediate augmentation showed a higher survival rate (97.6%, 95% CI: 93.4–99.9%) compared to those with delayed augmentation (91.7%, 95% CI: 83.4–97.5%), this difference was not statistically significant (P = 0.26). Peri-implant health outcomes, including marginal bone loss, were consistent across subgroups.

Conclusion

Replacing failed implants is often an attractive treatment option. While implants placed as replacements generally have lower survival rates compared to primary implants, immediate implant placement remains a viable option when adequate bone volume is present. The review supports the effectiveness of implant re-placement, with generally favourable.

Clinical relevance

Dental implants are widely used for replacing missing teeth, but implant failure is a known complication. Understanding the outcomes of implants placed in sites where implants have failed is important as this situation can present challenges, such as insufficient bone or altered soft tissue conditions. This article provides data on the survival and health outcomes of implants placed in these failed sites, which may provide benefit to clinicians in these scenarios.