plaque vs dental plaque

plaque and dental plaque both are nouns.

Word	Noun	Adjective	Verb	Adverb
plaque	Yes	No	No	No
dental plaque	Yes	No	No	No

As nouns, dental plaque is a hyponym of plaque; that is, dental plaque is a word with a more specific, narrower meaning than plaque:

plaque: (pathology) a small abnormal patch on or inside the body
dental plaque: a film of mucus and bacteria deposited on the teeth that encourages the development of dental caries

Other hyponyms of plaque include amyloid plaque, amyloid protein plaque, arterial plaque, bacterial plaque.

plaque (noun)	dental plaque (noun)
a memorial made of brass	a film of mucus and bacteria deposited on the teeth that encourages the development of dental caries
(pathology) a small abnormal patch on or inside the body