Effect of glycerin as a plasticizer on flexural strength in the fabrication of gypsum-based chip

Abstract

Background: Ceramic-based drug delivery systems has received significant attention in both medical and material domains. This study used gypsum as a base material for drug delivery chips, which has the potential to replace existing materials such as collagen and gelatin. The choice of gypsum as a material was based on a unique combination of osteoconductive, bioresorbable, and biodegradable characteristics. Methods: In this study, glycerin was added to distilled water at different concentrations (5%, 10%, 15%, 20%, and 25%) to increase the flexibility of gypsum. Calcium Sulfate Hemihydrate powder was then combined with a mixed solution of water and glycerin and stirred. The mixture was then placed in an acrylic mold measuring 25 x 3 x 1.5 mm and allowed to dry for 24 hours at room temperature. After that, the specimen was analyzed to determine flexural strength using the Universal Testing Machine with a three-point bending method at a crosshead speed of 0.5 mm/min. Results: Statistical analysis revealed that the inclusion of glycerin led to an increase in the percentage of strain. However, it has been observed that the mechanical strength of gypsum chips shows a proportional decrease with increasing glycerin concentration. Conclusions: It can be concluded that the addition of glycerin into the gypsum chip can increase the elasticity of the chip even though the flexural strength is reduced.