MK1 interlocking device, partially fixed on fixed dentures and partially connected to removable dentures. To a certain extent, MK1 has solved the requirements of the beneficiary for denture retention, chewing function, and aesthetic comfort, as well as the doctor's requirements for abutment protection. By transmitting force to the attachment to the abutment, MK1 greatly improves chewing force. At the same time, MK1 has a small volume and does not produce lateral force on the abutment when removed, providing good retention