odontology vs dentistry

odontology and dentistry both are nouns.

Word	Noun	Adjective	Verb	Adverb
odontology	Yes	No	No	No
dentistry	Yes	No	No	No

As nouns, odontology and dentistry are synonyms defined as:

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

Other synonyms of odontology include dental medicine.

odontology (noun)	dentistry (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