Histologic and histomorphometric report of three immediately loaded screw implants retrieved from man after a three-year loading period.

摘要

PURPOSE: The aim of the present study, in man, was an histologic and histomorphometric analysis of the peri-implant tissues in 3 immediately loaded screw implants retrieved, because of fracture, after a 3 year loading period. RESULTS: Mineralized tissue was present at the interface of all implants. The mean bone to implant contact percentage for the 3 implants was 56.3% +/- 5%. The histologic and histomorphometric data showed that mineralized tissues can be obtained in immediately loaded screw implants and that these mineralized tissues are maintained over a period of 3 years. The response of the osseous tissue was not disturbed by the stresses and strains transmitted at the interface. CONCLUSION: A high primary stability, obtained by the large threads of the screw-shaped implant, was probably a key factor in the long-term maintenance of a mineralized bone interface. The primary stability helps to resist micromotion, i.e., the relative movements between the implant surface and surrounding bone during functional loading.