The Efficacy of a Semi-Resorbable Membrane Based on Silk Fibroin-Glycerol on Bone Regeneration in Rabbit Calvarial Defects Compared to a Commercial Collagen Membrane

Silk fibroin-glycerol-based membranes were fabricated and characterized for use as a self-maintaining and non-collapsible semi-resorbable membrane in guided bone regeneration. The study assessed the bone regeneration capacity of silk fibroin-glycerol-based membranes compared to a collagen membrane in 10-mm circular bilateral calvarial defects of 20 male New Zealand white rabbits. The animals were divided into two sets of time frames of 4 and 12 weeks and allocated into four groups ( n = 5/group); an empty defect (E), a collagen membrane (Bio-Gide®; BG), a silk fibroin-glycerol-collagen membrane (SGC), and a silk fibroin-glycerol membrane (SG). The bone density (optical density, OD) from the 2D radiographs, tissue reaction from histological sections, new bone volume, and area from micro-CT and the histomorphometry were evaluated. The Mean OD of the E (34.49 ± 14.21%) and BG groups (35.71 ± 9.65%) at 12 weeks were higher than at 4 weeks, but the SGC (39.04 ± 7.94%) and SG (40.96 ± 9.25%) groups were lower at 4 weeks. The new bone volumes at 4 weeks of the SG (24.19 ± 1.35%) and SGC groups (24.19 ± 3.47%) were significantly higher than the BG group (16.93 ± 2.95%) but were not different from the E group (18.39±4.78%). At 12 weeks, the new bone volumes in the SGC (29.09 ± 3.81%), SG (29.11 ± 5.94%), and BG groups (26.26 ± 4.42%) were higher than in the E group (21.63 ± 5.81%) without statistical significance. Histological images in the SGC and SG groups showed slow biodegradation without a foreign body reaction. The new bone area at 4 weeks was lowest in BG (12.95 ± 5.44%), and the others were comparable. At 12 weeks, the new bone area in the E group (23.55±8.69%) was lower than the BG (31.42 ± 6.18%), SG (35.25 ± 13.92%), and SGC groups (36.35 ± 10.23%). Silk fibroin-glycerol-based membranes are semi-resorbable membranes that possess a self-maintaining property, have a barrier function without collapsing, and are successful in facilitating bone regeneration.