Reproducibility in the morphological and mechanical properties of a natural polymer for guided bone regeneration...

Dental barrier membranes play a key role in guided bone regeneration (GBR) to separate soft tissue from regenerating bone. Bioabsorbable collagen membranes, the gold standard in GBR procedures, are appealing due to elimination of the need for secondary surgeries and mechanical properties mimicking native tissue. However, challenges include rapid degradation, inconsistent reproducibility in mechanical and morphological properties, and use of animal-derived tissues. This study explored silk fibroin, a biocompatible and slowly bioabsorbable biomaterial as an alternative for GBR membranes. Silk fibroin showed comparable mechanical performance and demonstrated improved reproducibility. Two silk fibroin-based multilayered membranes (SF1 and SF2) were developed showing homogeneous appearance, density, and thickness, with lower variability than the other tested commercial options. These membranes exhibited elasto-plastic mechanical behaviour in both dry and hydrated states, supporting improved surgical handling and dimensional stability. Furthermore, elastic modulus in hydrated state (23.8 ± 3.2 MPa for SF1, 27.6 ± 3.9 MPa for SF2), burst pressure (17.5 ± 5.0 mmHg for SF1, 290.0 ± 32.6 mmHg for SF2), and force at first deformation in the suture retention strength test in hydrated state (0.10 ± 0.03 N for SF1, 0.26 ± 0.11 N for SF2) were comparable to commercial collagen membranes, suggesting the suitability for GBR applications. These findings provide a basis for further biological and preclinical characterization as well as clinical application of silk fibroin-based GBR membranes.