A sinus implant (10) includes a mounting hole (12) axially defined therein, a plurality of positioning threads (11) spirally upwardly extended around the periphery thereof and gradually reducing in width in direction from a bottom side toward an opposing top side thereof, one or multiple spiral grooves (14) extending around the periphery thereof across the positioning threads (11), and a pushing tip (15) of reduced diameter located at respective top ends of the positioning threads (11) and defining a flat end face (151) and a recess space (152) in the flat end face (151) in communication with each spiral groove (14).
