Fig. 2

Representative structures of sialolith. Microcomputed tomography (micro-CT) view of the sialolith (A). Hematoxylin and eosin (H&E) stain view of a sialolith (B). The signal of calcification initiated from the central nidus zone induces thick calcification of the intermediate compact zone and results in the repeated deposition of calcified material in the peripheral multi-layer zone.