The tooth and adaptor for dredging machines object of the present invention relates to a tooth or wear member which, attached to an adaptor or adaptor member, creates an assembly the purpose of which is to deepen and clean the beds of ports, rivers, channels, etc., removing therefrom sludge, stones, sand, etc., the adaptors being attached to the blades of the propellers and thus forming the cutter head of the dredging machine. The constructive features of the coupling between the tooth and the tooth bar or adaptor allow making better use of the cutting material of the tooth and a simple and quick replacement thereof in the adaptor, between other advantages.