Fig. 6: Assessment of performance after common physical and chemical insults.
From: Biomimetic supramolecular protein matrix restores structure and properties of human dental enamel
a Illustration of enamel abrasion due to routine tooth brushing and (b) Young’s modulus (E) and hardness (H) of native and remineralised (remin) enamel sections after 15 and 60 min of continuous brushing. c Illustration of tooth fracture due to physical insults and (d) apparent fracture toughness (Kc(app)) of different enamel samples (n = 3 samples). e Illustration of tooth wear due to chewing & grinding or other physical insults and volume and height loss evaluated in native and mineralised (f) enamel (n = 8 samples) and (g) dentine samples (n = 8 samples) after the chewing & grinding experiment. h Illustration of enamel erosion due to acid attack and (i) nanoindentation results (E and H) of native and remineralised enamel samples before and after exposure to acid for 15 min and 2 days. j SEM image (n = 3 samples) and (k) nanoindentation results (E and H) of enamel remineralised for 14 days using natural human saliva. SEM images showing ELR coating on prismatic enamel (l) before brushing, (m) after brushing for 15 min (equivalent to ~ 4 months of brushing), and (n) after remineralisation for 10 days (n = 3 samples). The image presented in (l) appears blurry due to a visual effect created by the ELR coating uniformly conforming over the enamel surfaces. In (b, i, k) bars represent the mean values of E and H while dot plot represents indentation measurements compiled from 3 independent experiments for each group. Data are presented as mean ± SD. Statistical significance was analysed using two-tailed Student’s t test (f, g) or two-sided one-way ANOVA (Tukey test) (b, d, i) in GraphPad Prism ver. 10. In (b) ** represents a significant difference p = 0.0055. In (d) ** represents significant difference p = 0.0083, * represents p = 0.0328. In (g) * in volume loss represents p = 0.0480 while * in height loss represents p = 0.0309. In (i) **** represents p < 0.0001, ** represents p = 0.0035. In (b, d, f, i), ‘ns’ represents no significant difference. Schematic illustrations in (a, c, e, h) were prepared by scientific illustrator Leonora Martínez Nuñez.
