Assertion: tooth's structure | /r/HasProperty | keratin
Facets:
Source sentences:
text: Immediately after the eruption enamel is covered by a specific film: Nasmyth's membrane or 'enamel cuticle', structure of embryological origin is composed of keratin which gives rise to the enamel organ.
text: Nasmyth membrane or enamel cuticle, structure of embryological origin is composed of keratin which gives rise to the enamel organ.