Implant-supported restorations were connected to commercially pure titanium endosteal implants 3 months in mandible and 6 months in maxilla after the implants were inserted into patient jaws. Modifications of titanium implant surfaces have reduced the waiting time for osseointegration, resulting in the development of the early loading concept, which is defined at present as a restoration in contact with the opposing dentition and placed at least 1 week after implant placement, but no later than 2 months afterward. Nowadays, immediate loading protocols have also been introduced, using the implants that are designed to enhance initial stability. Immediate loading eliminates the edentulous period of a patient. Although dentists widely accept these concepts of early and immediate loading, they agree the conventional loading concept is still necessary, which describes loading protocols later than 2 months after implant insertion. The timing of loading is determined mainly by the factors of a patient. This paper considers for what dental clinicians should be careful in implant-supported restoration procedures, considering the implant late failure.