Efficacy of propolis in remineralising artificially induced demineralisation of human enamel - An in-vitro study

OBJECTIVE: In this in vitro study, we aimed to analyse the enamel-remineralisation potential of propolis. MATERIALS AND METHODS: Twenty enamel blocks (N = 20) were randomly divided into two groups (n = 10). In group 1 (control), enamel blocks were brushed with artificial saliva (AS). In group 2, they were brushed with propolis oil. All the blocks were demineralised by exposing them to 6 wt% citric acid (pH: 2.2) for 5 min. Brushing was performed inside a tooth brushing simulation machine with manual toothbrushes. Each sample received 5,000 linear strokes. Surface microhardness analysis was performed for each sample at three time intervals (pre-demineralisation or baseline, post-demineralisation, and post-remineralisation) to obtain the Vickers hardness numbers (VHNs). RESULTS: An enhancement in the microhardness of the enamel samples was observed after brushing with propolis oil when compared with brushing using AS alone. In group 1 (control group), the mean baseline VHN was 583.66. It decreased to 116.23 after demineralisation and increased to 184.02 after remineralisation. The mean baseline VHN of group 2 was 506.91. It decreased to 317.60 after demineralisation and increased to 435.19 after remineralisation. The VHN values of both the groups revealed statistically significant differences (p < 0.05) in inter-group and intra-group comparisons. CONCLUSION: Brushing of enamel blocks with propolis led to a greater enhancement in their microhardness levels when compared with the control group. Future studies are essential to validate the exact mechanism of the beneficial effects of propolis on enamel.