cementum vs thickener

cementum

noun
  • A bony substance that covers the root of a tooth; cement. 

thickener

noun
  • Any substance added to something in order to thicken it; a thickening agent; a binder. 

  • That which thickens. 

How often have the words cementum and thickener occurred in a corpus of books? (source: Google Ngram Viewer )