Gums filled with bad things to suck (9)

I believe the answer is:

pastilles

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'things to suck' is the definition.
I can't judge whether this defines the answer.

'gums filled with bad' is the wordplay.
'gums' becomes 'pastes' (I can't explain this - if you can you should believe this answer much more).
'filled with' means one lot of letters goes inside another.
'bad' becomes 'ill' (associated in meaning).
'pastes' enclosing 'ill' is 'PASTILLES'.

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I've seen this clue in The Sunday Times.

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