Effect of reactive soft tissue combined with injectable platelet-rich fibrin for alveolar ridge preservation in severe defect molar sites: a retrospective cohort study.

OBJECTIVE: The purpose of this study was to compare the alveolar ridge preservation (ARP) effect using reactive soft tissue (RST) for socket sealing to guided bone regeneration (GBR) with collagen membrane and sponge in type IV molar sockets. MATERIALS AND METHODS: This retrospective study included 40 sites. Bone regeneration outcomes were evaluated by comparing CBCT images preoperatively (T0), immediately postoperatively (T1), and at a 6-month follow-up (T2). Measurements included changes in horizontal ridge width, vertical ridge height, graft material retention rate, post-operative surgical complications, incidence of secondary bone grafting at implant placement, and short-term implant survival rate. RESULTS: Both groups showed a significant increase in horizontal bone width at 1 mm, 3 mm, and 5 mm below the crest, with no differences. From T2 to T1, the RST group demonstrated superior vertical stability at the crest center (gain of 0.34 mm vs. loss of 0.88 mm in controls, P = 0.023) and a higher graft material retention rate (92.84% vs. 68.04%, P = 0.003). No significant difference was found in the secondary bone grafting rate, and the short-term implant survival rate was 100% in both groups. CONCLUSIONS: RST combined with DBBM reduced ridge resorption in severe defect molar sites. It shows a better tendency in preserving vertical ridge height and graft retention compared to the GBR. CLINICAL RELEVANCE: Using RST for socket sealing achieves comparable bone preservation to the GBR in severe defect molars, while simplifying the surgical procedure and reducing costs.