logopedist vs orthophonist

logopedist

noun
  • A specialist who deals with the correction of the speech sounds, the disorders in writing, reading, the ability to create any forms of mathematical operations, disorders in use of language and swallowing disorders. 

orthophonist

noun
  • speech therapist 

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