Check Screws- Check screw access holes for closure.
If screw access holes are uncovered, such as the bar-retained dentures, make sure that are free from debris. If screws can be seen, gentle movement with a probe or an explorer will allow you to detect unscrewing or possible fracture. At least once a year, an appropriate screwdriver should be used to verify tightening. If you find a loose screw ideally replace it with a new one.
Inspect the connection between the prosthesis and the abutment when supragingival. Increased distance between these elements may be a sign of uncementing or unscrewing of the prosthesis.
Note that in the presence of periosteal or blade implants, as well as some root-form implants that contain the abutment, any loosening is due to loss of osseointegration or fracture of the implant itself.