Comparison between Platelet Rich Fibrin and Resorbable Collagen Membrane in Inferior Alveolar Nerve Lateralization and Immediate Dental Implant Placement in Severely Resorbed Mandibles Among Yemeni Patients in Sana'a city

Background: Barrier membranes such as resorbable collagen and platelet-rich fibrin (PRF) are commonly used in surgical procedures to enhance healing and reduce the risk of neurosensory disturbance (NDs). While collagen membranes act as passive barriers, PRF, an autologous, cost-effective alternative, actively promotes tissue regeneration through sustained release of growth factors. Objective : To compare the efficacy of platelet-rich fibrin (PRF) and resorbable collagen membranes in protecting the inferior alveolar nerve (IAN) and enhancing healing following nerve injury. Methods: A prospective, randomized clinical trial involving nine edentulous posterior mandible sites requiring inferior alveolar nerve lateralization (IANL) was conducted in Yemen from July to November 2024. Following implant placement, patients were randomly assigned to receive either a collagen membrane or autologous platelet-rich fibrin (PRF) membrane placed between the nerve and implants. The nerve function and implant success were monitored postoperatively. Data were analyzed using Friedman and Wilcoxon tests, with significance set at p < 0.05. Results: The study included patients aged 24–72 years with a mean age of 56.22 ± 16.49, with a male predominance (77.78%). Surgical procedures were performed on the right side in 55.56% and on the left side in 44.44% of cases. A statistically significant difference in ND was observed across follow-ups on day one, week one, month one, month three, and month six (χ² = 30.3, p < 0.001). Pairwise comparisons revealed significant improvements from day one to month one (p = 0.03), day one to month three (p = 0.008), and day one to month six (p = 0.005), whereas the difference between day one and week one was not significant (p = 1.00). No significant correlations were found between ND recovery and patient age or membrane type at any follow-up interval (P > 0.05). Conclusions: This preliminary study demonstrated that IANL with immediate implant placement is an effective technique for rehabilitating atrophic posterior mandibles. ND improved significantly within six months post-surgery, with most patients recovering fully or experiencing only mild symptoms. Implant success was high, and no significant link was found between nerve recovery and the membrane type.