Fig. 4

Processed SAXS signal of specimens 100818 (no apparent caries) represented by the upper four images and 111038 represented by the lower four images (prominent caries) in the q-range corresponding to 50–100 nm and cuts through SRμCT data. Well-known features are made visible in the different channels. Ebners lines, Hunter–Schreger bands and striae of Retzius can best be identified in the total mean scattering signal (a), while overall tubule orientation can be spotted in the SRμCT data (b, f). The de-mineralized carious region yields a stronger scattering signal than the unaffected surrounding tooth hard tissue (e). The carious region is not apparent in the orientation channel (h)