prosthodontics vs prosthodontia

prosthodontics and prosthodontia both are nouns.

Word	Noun	Adjective	Verb	Adverb
prosthodontics	Yes	No	No	No
prosthodontia	Yes	No	No	No

As nouns, prosthodontics and prosthodontia are synonyms defined as:

prosthodontics and prosthodontia: the branch of dentistry dealing with the replacement of teeth and related mouth or jaw structures by artificial devices

prosthodontics (noun)	prosthodontia (noun)
the branch of dentistry dealing with the replacement of teeth and related mouth or jaw structures by artificial devices	the branch of dentistry dealing with the replacement of teeth and related mouth or jaw structures by artificial devices