Crushing apparatus for a stone-crushing machine, intended to be fixed to a rotor roller of a stone-crushing machine together with a plurality of equivalent crushing apparatuses, and such crushing apparatus comprises: - a support base intended to be fixed on the rotor roller of said stone-crushing machine and provided with a housing seat; - at least one tooth, which is mainly extended along a longitudinal axis, and is provided with: - a stem inserted within said housing seat of said support base; - a work head for crushing stone material, which is integral with said stem, is extended starting from a first end of said stem and is provided with a projecting shoulder, which is extended transverse to the longitudinal axis of said tooth in abutment against a first edge of said housing seat; - said stem being provided with a retention portion, which is extended up to a second end opposite said first end; - locking means mechanically associated with the retention portion of the stem of said tooth in order to maintain said tooth constrained to said support base; wherein said locking means comprise: - a first substantially annular groove obtained on the retention portion of the stem of said tooth; - a second substantially annular groove, facing towards the first annular groove of the stem of said tooth, obtained on said support base in proximity to a second edge of said housing seat, opposite the first edge; - a plurality of locking balls inserted in said first and second annular grooves (13, 16), in order to constrain the stem of said tooth within the housing seat of said support base; said crushing apparatus being characterized in that said locking means also comprise a stop element mechanically constrained to said support base and at least partially placed to interfere with said locking balls within said second annular groove in order to stop said locking balls in position. - a support base intended to be fixed on the rotor roller of said stone-crushing machine and provided with a housing seat; - at least one tooth, which is mainly extended along a longitudinal axis, and is provided with: - a stem inserted within said housing seat of said support base; - a work head for crushing stone material, which is integral with said stem, is extended starting from a first end of said stem and is provided with a projecting shoulder, which is extended transverse to the longitudinal axis of said tooth in abutment against a first edge of said housing seat; - said stem being provided with a retention portion, which is extended up to a second end opposite said first end; - a stem inserted within said housing seat of said support base; - a work head for crushing stone material, which is integral with said stem, is extended starting from a first end of said stem and is provided with a projecting shoulder, which is extended transverse to the longitudinal axis of said tooth in abutment against a first edge of said housing seat; - said stem being provided with a retention portion, which is extended up to a second end opposite said first end; - locking means mechanically associated with the retention portion of the stem of said tooth in order to maintain said tooth constrained to said support base; wherein said locking means comprise: - a first substantially annular groove obtained on the retention portion of the stem of said tooth; - a second substantially annular groove, facing towards the first annular groove of the stem of said tooth, obtained on said support base in proximity to a second edge of said housing seat, opposite the first edge; - a plurality of locking balls inserted in said first and second annular grooves (13, 16), in order to constrain the stem of said tooth within the housing seat of said support base; - a first substantially annular groove obtained on the retention portion of the stem of said tooth; - a second substantially annular groove, facing towards the first annular groove of the stem of said tooth, obtained on said support base in proximity to a second edge of said housing seat, opposite the first edge; - a plurality of locking balls inserted in said first and second annular grooves (13, 16), in order to constrain the stem of said tooth within the housing seat of said support base; said crushing apparatus being characterized in that said locking means also comprise a stop element mechanically constrained to said support base and at least partially placed to interfere with said locking balls within said second annular groove in order to stop said locking balls in position.