A pulverizing attachment for an excavator, comprising: a plurality of tooth members, each tooth member having a body portion, the body portion having opposing forward and rearward abutment surfaces defining a body length, each tooth member having a longitudinal slot extending between the forward and rearward abutment surfaces, the longitudinal slot having a pre-defined cross-sectional shape, a relief slot disposed proximate each abutment surface, the relief slot extending substantially transverse to the longitudinal slot through a portion of the body portion thereby producing a flexible end portion capable of deflection upon application of a longitudinal compression force; an upper jaw and a lower jaw, each jaw having a plurality of spaced tooth rails onto which one of the plurality of tooth members is slidably received, each tooth rail having a cross- sectional shape complimentary to the pre-defined cross-sectional shape of the longitudinal slot of the plurality of tooth members, each tooth rail having a length defined by front end and a rearward stop surface, the rearward stop surface abutting the rearward abutment surface of the tooth member slidably received thereon; upper and lower jaw cover plates, each cover plate having a plurality of spaced tooth retaining ribs (512, 612) corresponding to each of the plurality of spaced tooth rails of the upper and lower jaws (100, 200), each retaining rib (512, 612) abutting the forward abutment surface of each of the tooth members slidably received onto each of the tooth rails, the retaining ribs (512, 612) applying a longitudinal compression force deflecting the flexible end portions of each of the tooth members received on each of the tooth rails; whereby the longitudinal compression force in cooperation with the complimentary shape of the longitudinal slot and the tooth rail, rigidly restrain each tooth member with respect to the tooth rail. a plurality of tooth members, each tooth member having a body portion, the body portion having opposing forward and rearward abutment surfaces defining a body length, each tooth member having a longitudinal slot extending between the forward and rearward abutment surfaces, the longitudinal slot having a pre-defined cross-sectional shape, a relief slot disposed proximate each abutment surface, the relief slot extending substantially transverse to the longitudinal slot through a portion of the body portion thereby producing a flexible end portion capable of deflection upon application of a longitudinal compression force; an upper jaw and a lower jaw, each jaw having a plurality of spaced tooth rails onto which one of the plurality of tooth members is slidably received, each tooth rail having a cross- sectional shape complimentary to the pre-defined cross-sectional shape of the longitudinal slot of the plurality of tooth members, each tooth rail having a length defined by front end and a rearward stop surface, the rearward stop surface abutting the rearward abutment surface of the tooth member slidably received thereon; upper and lower jaw cover plates, each cover plate having a plurality of spaced tooth retaining ribs (512, 612) corresponding to each of the plurality of spaced tooth rails of the upper and lower jaws (100, 200), each retaining rib (512, 612) abutting the forward abutment surface of each of the tooth members slidably received onto each of the tooth rails, the retaining ribs (512, 612) applying a longitudinal compression force deflecting the flexible end portions of each of the tooth members received on each of the tooth rails; whereby the longitudinal compression force in cooperation with the complimentary shape of the longitudinal slot and the tooth rail, rigidly restrain each tooth member with respect to the tooth rail.