Novel Rhinological Application of Polylactic Acid-An In Vitro Study

A novel approach to the treatment of sinusitis is the use of nasal stents. The stent is loaded with a corticosteroid, which prevents complications in the wound-healing process. The design is such that it will prevent the sinus from closing again. The stent is 3D printed using a fused deposition modeling printer, which enhances the customization. The polymer utilized for the purpose of 3D printing is polylactic acid (PLA). The compatibility between the drugs and polymers is confirmed by FT-IR and DSC. The drug is loaded onto the polymer by soaking the stent in the drug's solvent, known as the solvent casting method. Using this method, approximately 68% of drug loading is found to be achieved onto the PLA filaments, and a total of 72.8% of drug loading is obtained in terms of the 3D-printed stent. Drug loading is confirmed by the morphological characteristics of the stent by SEM, where the loaded drug is clearly visible as white specks on the surface of the stent. Drug release characterization is conducted by dissolution studies, which also confirm drug loading. The dissolution studies show that the release of drugs from the stent is constant and not erratic. Biodegradation studies were conducted after increasing the rate of degradation of PLA by soaking it in PBS for a predetermined duration of time. The mechanical properties of the stent, such as stress factor and maximum displacement, are discussed. The stent has a hairpin-like mechanism for opening inside the nasal cavity.