OBJECTIVES: Excess loading has been often cited as a reason for the failure of dental implants or bone loss post-osseointegration. The available data from animal studies have failed to show a clear role for excessive loading in the loss of osseointegration. The present case documentations aimed at providing a deeper insight into the medium- to long-term influence of occlusal loading on osseointegrated implants, and describe the clinical manifestations of such pathology. MATERIAL AND METHODS: Two cases of loss of osseointegration are documented with single implants in the posterior maxilla. Implant mobility was in both cases the first and only sign of pathology, with the absence of plaque-induced inflammation and marginal bone loss. RESULTS: Re-osseointegration of the implants was achieved after the removal of the prosthetic reconstruction. CONCLUSIONS: The two cases reported that the loss of osseointegration in the absence of plaque-induced peri-implant inflammation is possible, although the clinical manifestations were very different to these of peri-implantitis. Once the occlusal loading was withdrawn, re-osseointegration was clinically confirmed in a period of 6-8 months.