Fabrication and characterization of HA-oyster shell based on biopolymer - propolis as an agent of dental enamel remineralization materialti

Abstract

This study aims to make gel composites by synthesizing and characterizing hydroxyapatite (HA) from oyster shell (Crassostrea gigas) as an essential ingredient for remineralization gel in teeth. The method used to synthesize HA is the precipitation method. HA is synthesized with a variation of calcination for 8 h at 1000 °C and aging time for 24 h to get the best result. The size of the HA crystal obtained is 14 ± 4 nm, with a degree of crystallinity of 91.54%. The result of the HA-oyster shell is used to synthesize gel composites. The gels used as parameters are composition variations: basis gel (basis gel as a negative control), HA gel, propolis gel, and HA-propolis gel. The essential ingredients of oyster shell, HA, and composite gels are treated by physicochemical tests in SEM, XRD, and FTIR characterization. The gel composites are treated using antibacterial tests with Streptococcus mutants, Streptococcus sanguinis, and Lactobacillus acidophilus. The antibacterial test aims to determine the inhibition of bacteria that cause caries in teeth. The best antibacterial test results are found in HA-propolis gel with the inhibition zone diameter of S.Mutants 22 ± 0.2 mm, S. Sanguinis 22 ± 0.3 mm, and L.Acidophilus 21 ± 0.2 mm. In addition to the antibacterial test, the gel was treated with a feasibility test to determine the viability of viable cells (MC3T3-E1) when incubated for 48 h. The MTT test shows that the results of the HA gel sample gave significant cell growth, which was 92.80% at the low concentration. The physicochemical, antibacterial, and MTT (Viability) test results confirm that the HA-propolis gel composite could potentially improve dental enamel caries with the remineralization process.