Clinical outcomes of PLLA/PGA (85:15) versus nonresorbable Synpor implants in 3D model-assisted reconstruction of large orbital blowout fractures

This study aimed to evaluate the efficacy and safety of poly-L-lactic acid/polyglycolic acid (PLLA/PGA, 85:15) implants compared with nonresorbable Synpor implants for 3D model-assisted reconstruction of large orbital blowout fractures. This retrospective single-center cohort study included 50 patients with unilateral orbital blowout fractures, categorized into four groups according to implant material and defect area (DA): A1 (Synpor, DA < 2 cm 2 ), A2 (Synpor, DA 2–3 cm 2 ), B1 (PLLA/PGA, DA < 2 cm 2 ), and B2 (PLLA/PGA, DA 2–3 cm 2 ). The postoperative follow-up duration ranged from 6.0 to 45.1 months, with a median follow-up of 6.9 months. Orbital volume ratio (OVR), enophthalmos, diplopia, and sensory disturbance were assessed preoperatively and at 1 week and 6 months postoperatively. Complications were recorded. At 6 months, the mean OVR difference was − 0.034% (95% CI, -1.535 to 1.467; adjusted P = 1.000) for A1 vs. B1 and 0.605% (95% CI, -0.927 to 2.137; adjusted P = 0.930) for A2 vs. B2, suggesting that no statistically significant material-related difference was detected. Enophthalmos resolved at 1 week and showed mild recurrence at 6 months in groups A2 and B2. Diplopia decreased in groups A1 and B1 and increased slightly in groups A2 and B2 at 1 week but almost disappeared at 6 months. No difference in sensory disturbance was observed between the groups. Only one case of delayed hematoma was observed in group A2. PLLA/PGA (85:15) resorbable implants may provide stable reconstruction of large orbital blowout fractures and may be an effective alternative to nonresorbable implants.