dentistry vs dental medicine

dentistry and dental medicine both are nouns.

Word	Noun	Adjective	Verb	Adverb
dentistry	Yes	No	No	No
dental medicine	Yes	No	No	No

As nouns, dentistry and dental medicine are synonyms defined as:

dentistry and dental medicine: the branch of medicine dealing with the anatomy and development and diseases of the teeth

Other synonyms of dentistry include odontology.

dentistry (noun)	dental medicine (noun)
the branch of medicine dealing with the anatomy and development and diseases of the teeth	the branch of medicine dealing with the anatomy and development and diseases of the teeth