Effect of Dehydrothermal Treatment on the Structure and Properties of a Collagen-Based Heterogeneous Bilayer Membrane

The use of the guided bone regeneration technique in oral surgery has been proven to be an effective method for repairing alveolar bone defects. However, the success of this technique heavily relies on the barrier membrane used. Collagen is the most frequently used raw material to fabricate a resorbable barrier membrane, which has some drawbacks during clinical application, such as poor mechanical properties and rapid biodegradation. To address these issues, a new approach was developed for the preparation of collagen-based heterogeneous bilayer membranes, which involves a combination of physical treatment and biocompatible chemical cross-linking. The dialdehyde carboxymethyl cellulose was used to cross-link collagen to fabricate the membrane, and dehydrothermal (DHT) treatment was applied to enhance its properties. The results showed that DHT treatment apparently improved the structure stability and compression strength in both dry and swollen states. The biodegradation rate of the bilayer membrane was depressed, and the porosity was improved by dehydrogenation. The bilayer membrane was found to have good cytocompatibility. Moreover, the compact lower layer of the bilayer membrane possessed a strong barrier function to fibroblasts while the loose upper layer was able to enhance the adhesion, proliferation, and osteogenic differentiation of osteoblasts. Overall, the collagen-based heterogeneous bilayer membrane has great potential for the application in guided bone regeneration. For the membrane, the improved mechanical properties, reduced biodegradation rate, and enhanced osteoblast response make it a promising material for oral surgery applications.