Alveolar ridge preservation versus unassisted socket healing following tooth extraction: a systematic review of controlled clinical studies and meta-analysis of randomised trials.

PURPOSE: To estimate early horizontal ridge-width and explicit buccal/facial vertical hard-tissue loss after alveolar ridge preservation (ARP) versus unassisted socket healing.

METHODS

The review was registered in PROSPERO (CRD420261432689). PubMed/MEDLINE, Scopus, Web of Science Core Collection, Embase.com, and ClinicalTrials.gov were searched on 24 June 2026; CENTRAL provided supplementary verification on 1 July 2026. Two reviewers independently selected reports. One reviewer extracted data; the second verified classifications and effect inputs. Randomised direct comparisons were pooled using REML random-effects models with Hartung-Knapp inference. Risk of bias and certainty were assessed with RoB 2 and GRADE.

RESULTS

Of 1,864 records, 1,739 were screened, and 62 underwent full-text assessment. 28 direct comparison reports were eligible; 20 randomised studies contributed quantitatively, and 8 reports were narrative-only. ARP was associated with less horizontal ridge-width loss (k = 18; MD - 1.37 mm, 95% CI - 1.80 to - 0.94; I² = 75.9%; prediction interval - 2.86 to 0.12) and less explicit buccal/facial vertical loss (k = 13; MD - 1.18 mm, 95% CI - 1.61 to - 0.75; I² = 74.3%; prediction interval - 2.54 to 0.17). Certainty was low for both. The exploratory broad vertical/buccal synthesis favoured ARP (k = 16; MD - 1.26 mm, 95% CI - 1.63 to - 0.89) with very low certainty.

CONCLUSION

ARP may reduce early dimensional loss, but substantial heterogeneity and prediction intervals including no effect limit generalisability. Evidence does not establish universal indications, intervention superiority, or long-term implant, aesthetic, or patient-reported benefit.