Evaluation of alveolar ridge preservation using collagen and platelet-rich fibrin: A systematic review.

BACKGROUND

Alveolar ridge resorption following tooth extraction may compromise future implant placement and aesthetic outcomes. Several biomaterials have been proposed to limit post-extraction dimensional changes, among which collagen-based materials and platelet-rich fibrin (PRF) are widely used. The aim of this systematic review was to evaluate the effectiveness of collagen and PRF in alveolar ridge preservation compared with spontaneous healing.

MATERIAL AND

METHODS

This systematic review was conducted according to PRISMA 2020 guidelines and registered in PROSPERO (CRD42024489237). An electronic search was performed in PubMed, Scopus to identify randomized controlled trials (RCTs) published from 2014 onwards. Studies conducted in adult humans that evaluated horizontal and/or vertical alveolar ridge changes after tooth extraction were included. Risk of bias was assessed using the Cochrane RoB 2 tool.

RESULTS

Sixteen RCTs were included. Collagen-based interventions, particularly when combined with bone grafts such as deproteinized bovine bone mineral (DBBM), demonstrated a significant reduction in vertical and horizontal bone loss compared with spontaneous healing in several studies. PRF-based protocols showed heterogeneous results regarding dimensional bone preservation, with limited benefit when PRF was used alone. However, PRF-especially advanced or recurrent applications-was consistently associated with improved soft tissue healing and reduced postoperative pain. Considerable heterogeneity was observed in biomaterial preparation, application protocols, follow-up duration, and outcome assessment.

CONCLUSIONS

Both collagen and PRF can contribute to alveolar ridge preservation after tooth extraction, although their clinical benefits differ. Collagen, particularly when combined with bone grafts, appears more effective in preserving alveolar dimensions, while PRF provides greater advantages in soft tissue healing and postoperative pain control. The choice of biomaterial should be guided by the clinical objective and extraction site. Further well-designed, standardized long-term RCTs are needed to establish definitive clinical recommendations.