Earl involved in romp, damages tooth (8)

I believe the answer is:

premolar

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'tooth' is the definition.
(I know that premolar is a type of tooth)

I don't understand the remainder of the clue.

(Other definitions for premolar that I've seen before include "Grinder" , "Type of tooth" , "Tooth -- real romp (anag)" .)

I've seen this clue in The Irish Times.

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