While we might colloquially say things like "a collection of plaque" or "a layer of plaque", there's no established single word to describe a group of plaque.
This is likely because:
* Plaque is usually a singular, non-countable entity: We talk about "plaque build-up" or "plaque on teeth", not individual plaques.
* It's not a traditional "grouping" noun: Collective nouns like "flock" or "herd" describe living organisms that gather together.
If you're trying to be specific about the type of plaque you're referring to, you might describe it using other terms, such as:
* A deposit of plaque
* A film of plaque
* A layer of plaque
Ultimately, the best way to describe a group of plaque depends on the context and what you're trying to convey.