Apparatus for preventing dental implant abutment from being loosened

An apparatus for preventing an abutment from being loosened in a dental implant comprising:

• a fixture (10) which is fixedly installed in a jawbone (1) and has a screw hole (13);
• an abutment (20) which has a lower portion coupled to the fixture (10) and having an upper hole (23a) with a bottom surface (24) and a lower hole 23b and has an upper portion in which an artificial tooth (9) is provided;
• and a fastening screw (40) which has a threaded part (42) successively passing through the upper hole (23a) and the lower hole (23b) of the abutment (20) to fix the abutment (20), which is coupled to the screw hole (13) of the fixture (10), to the fixture (10),
• wherein the apparatus for preventing the abutment (20) coupled to the fixture (10) from being loosened comprises:
• at least one coupling protrusion or coupling groove formed in the bottom surface (24) of the upper hole (23a) of the abutment (20);
• and an anti-loosening washer (30) which is inserted into and installed in the upper hole (23a) of the abutment (20) in a coaxial direction, has a screw hole (31) passing therethrough in a central axis direction to allow the threaded part (42) of the fastening screw (40) to pass therethrough in a screw coupling manner, and is provided with at least one coupling groove or coupling protrusion, which is coupled to be engaged with the coupling protrusion or the coupling groove of the abutment (20), on a bottom surface (33),
• wherein when the threaded part (42) of the fastening screw (40) passes through the screw hole (31) in the screw coupling manner and is coupled to the screw hole (13) of the fixture (10), the coupling groove or the coupling protrusion of the bottom surface (33) is shape-coupled to the coupling protrusion (25) or the coupling groove of the upper hole bottom surface (24) of the abutment (20).