Novel Functional Asymmetric Poly(Lactid Acid)/Gelatin Composite Membrane For Guided Periodontal Tissue Regeneration

Periodontitis, the greatest threat to oral health, is a chronic disease that leads toinflammation of gingiva and periodontal tissue. Periodontitis can result in irreversibledamage to periodontal tissues, which is the main reason of losing teeth. Guided tissueregeneration (GTR), a common method for periodontal tissue regeneration, has beenapplied widely in conventional clinical treatment. However, degradable regenerationmembranes made from natural materials usually degrade uncontrollably in a shorttime and cannot meet the time requirement for peridontal tissue regeneration. On theother hand, regeneration membranes made from synthetic materials degrade tooslowly, which needs a secondary surgery to remove the membrane. In addition,dysbacteriosis is the major contributor of the inflamation in periodontitis. And theovergrowth of the anaerobic bacteria deteriorate the condition and also damage theimplanted membrane. Therefore, the aim of this research is to design a new functionalasymmetric poly(lactid acid)/gelatin composite membrane for periodontal tissueengineering. The results showed that the membrane is biocompatible, degradable ratecontrollable, antibacterial and osteogenesis inducible.Methods：(1) Electrospinning and freeze-drying methods were used to fabricate thePLA/gelatin composite membrane. Metronidazole and bioglass were loadedsuccessfully. The surface morphology and the internal structure were investigated.(2) The biocompatibility and cell proliferation of blended metronidazole andpolylactic electrospun membrane was evaluated. Metronidazole release of the composite membrane was measured and the cell penetration ability of the membranewas evaluated.(3) The bioactivity and biocompatibility of gelatin-45S5composite scaffold wereinvestigated. Ion (Ca, Si) release of scaffold was measured by ICP. Thetranscriptioanl level of osteogenic differentiation makers (alkaline phosphatase, bonesialoprotein and collagen type I) were examined by real-time PCR.Results：The PLA/gelatin composite membrane was fabricated successfullythrough optimization of experimental condition. The blended metronidazole andpolylactic electrospun membrane had good biocompatibility and cell proliferation rate.It released metronidazole showly in32days while working as a fibroblast barrier. Thegelatin-45S5composite scaffold had a good bioactivity response and it couldup-regulate Alpl and Bsp expression of rat BMSCs.Conclusion:This novel scaffold is biocompatible, controllably degradable,antibacterial, able to promote osteogenic differentiation and function as a barrier toexclude fibroblast from bone defect area. It has more potential for clinical applicationcompared to old generation regeneration membranes.