Green’s Dictionary of Slang

(US) teeth.

1944		J.S. Pennell Hist. of Rome Hanks 20: You sound purty funny without them ca’tridge biters, [...] They was reg’lar hoss teeth.
1946		Mezzrow & Wolfe Really the Blues 188: My biters were going bad along with all my other parts.
1960		(con. 1950-1960) R.A. Freeman Dict. Inmate Sl. (Walla Walla, WA) 11: Biters – teeth.