In our study, we have demonstrated that 3D scanning provides a powerful tool for the examination of explanted worn implants. The 3D models of 6 worn hip and 6 worn knee implants were created by 3D scanning and compared to the original geometries. The root causes of the failure of the implants could be assumed even without information about the service of the implant. This can help in the design of more durable and robust implants and to select the most critical operation parameters, and to avoid premature loosening.  Kulcsszavak: hip implant, knee implant, wear process, 3D scanning, failure process analysis