boob implant vs breast implant

boob implant

noun
  • Synonym of breast implant 

breast implant

noun
  • A medical prosthesis used to augment, reconstruct, or create the physical form of breasts (the organs on the front of the [typically female] chest). 

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