Evaluation of Peri-Implant Bone Response in Implants Retrieved for Fracture After More Than 20 Years of Loading: A Case Series

Abstract

Analysis of human retrieved dental implants is a useful tool in the evaluation of implant success and failure. More human histological data are needed from samples of long-term implant service. The aim of the present case series was a histological and histomorphometrical evaluation of the peri-implant bone responses in implants retrieved for fracture after more than 20 years loading. The archives of the Implant Retrieval Center of the Department of Medical, Oral and Biotechnological Sciences of the University of Chieti-Pescara, Italy were searched. A total of 5 implants, retrieved after a loading period of more than 20 years, were found: 2 had been retrieved after 20 years, 1 after 22 years, 1 after 25 years, and 1 after 27 years. All these implants were histologically processed. Compact, mature bone in close contact with the implant surface was observed in all specimens, with no gaps or connective tissue at the interface. Bone in different maturation stages was found around some implants. Primarily newly formed bone was observed in proximity of the implant surface, while mature compact bone with many remodeling areas and cement lines were detected in areas distant from the implant. Many primary and secondary osteons were present. Bone to implant contact percentage varied from 37.2% to 76%. In conclusion, histology and histomorphometry showed that even after many years of function, all implants presented more than adequate bone to implant contact and they appeared to be very well integrated in the peri-implant bone.

Immediate and delayed loading of fixed dental prostheses supported by single or two splinted implants: A histomorphometric study in dogs

“…Human studies documenting osseointegration histometrically are relatively sparse. However, a large number of reports on histometric analyses of retrieved implants are available . Among these, one study reported data on 17 implants loaded between 4 and 20 years that were retrieved for different reasons from patients and prepared for histometric analyses .…”

Dental Implant Fractures – Aetiology, Treatment and Case Report

“…Mangano et al, [19] Evaluation of the peri-implantbone responses in implantsretrieved for fractureaftermore than 20 yearsloading.…”

“…"Prosthetic factors" include loosening or torsion of the prosthetic screws, cantilevers and ceramic fractures. In the presence of more than three factors which pertaini to one or more of these categories, the risk of fractures is high [16][17][18][19].…”

“…Mechanical problems which occur include fractures. Metal fatigue caused by biomechanical overloading appears to be the most frequent cause [16][17][18][19].…”

Peri‐implant bone response to retrieved human zirconia oral implants after a 4‐year loading period: A histologic and histomorphometric evaluation of 22 cases

“…Besides several histological reports on the performance of titanium and zirconia oral implants in animal models, there is little known about peri‐implant hard tissue alterations in humans. For titanium oral implants, several human case series and retrieval studies are available including up to 216 implants after different loading periods . For zirconia oral implants, only one case report on a single implant after six months of oral exposure exists .…”