The most common and most likely answer to this crossword clue is the 10 letter word TOOTHPICKS
I've seen this crossword clue in The Guardian
T
O
O
T
H
P
I
C
K
S
Buddy explains!
The straight part
We know that "They remove unwanted bits" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case they remove unwanted bits = toothpicks.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TOOTHPICKS mean?
TOOTHPICKS noun- A small, usually wooden, stick, often pointed at both ends, for removing food residue from between the teeth.