Histological features of peri-implant bone subjected to overload

Purpose: The aim of this review has been to investigate the histological findings of bone structure surrounding implants subjected to excessive load. Materials and methods: Clinical and pre-clinical histological studies that observed overloaded intraoral implants were included. Results: All included studies (n = 15) were conducted on animals. Most of them failed to find pathological alteration in the microstructure of bone surrounding overloaded implants. Overload and infection alone may induce bone loss, but related lesions have different and peculiar features. Conclusions: The different histological features observed around implants subjected to overload or to ligature-induced peri-implantitis may indicate a specific pathogenetic mechanism for overload or infection-induced loss of osseointegration. The clinical significance of these findings should be confirmed in human studies.