Screw loosening in abutment: causes, origin mechanism, complications and management

Introduction and goal: Tooth replacement with dental implants is an invasive method, demanding in time and money. For these reasons, it is important to understand the technical complications that occurs in five years in about 12% of crowns on dental implants. Loosening of the screw in the abutment can have serious consequences for the patient, from the destruction of the crown when trying to find the fixation screw, associated with bacterial colonization leading to perimplantitis or its accentuation, to the fracture of the screw or fixture. The aim of the presented communication is to present current knowledge about the causes of screw loosening in the abutment, their prevention and a suitable method of treatment. Conclusion: Loosening the screw in the abutment is a common occurrence with adverse consequences that may jeopardize functionality, aesthetics and treatment success. This is not a devastating complication, but recurrence is not desirable. A loose screw can be an early warning of inadequate replacement biomechanics, or implant overload. Accurate diagnosis is also necessary so that an implant with loss of osseointegration is not considered a loose crown on the implant and vice versa.