noun
interdental brush
A small brush used to clean between teeth; common in dental care contexts.
歯間ブラシを使うと、歯と歯の間の汚れがよく取れます。
Using an interdental brush removes plaque between teeth effectively.
デンタルフロス is dental floss, a thread for cleaning between teeth, while 歯間ブラシ is a small brush for wider gaps.
Compound of 歯間 (shikan, 'between teeth') and ブラシ (burashi, from English 'brush').