Replace screw with self-tapping screw(s) in metal or plastic frame with a spring hinge.

Standard hinges are made up of barrels that fit into each other like a zipper with a small screw that slides into the middle to keep the barrels in place. This allows the arms (or temples) to move in and out while still keeping them firmly attached to the frame front. These simple hinges are found on a wide range of frames.

Missing Screw in Temple with Spring Hinge