Fig. 1.

Silk hydrogel preparation and rabbit sinus floor elevation surgery: (a) Liquid phase silk solution transforms into solid silk hydrogel by ultrasonication. (b) Schematic illustration of the mechanism of silk sol-gel transition due to inter-chain physical crosslinked β-sheet structures formed after ultrasonication. (c) Injectable property of silk gel. (d) Silk gel being injected into the rabbit sinus from the small bony window. (e) Diagram of elevated sinus in sagittal plane section. Yellow area represents silk gel in the sinus cavity. The maximal distance between sinus bony floor and raised nasal dorsum is defined as the augmented height of sinus (arrow = elevated sinus mucosa).