Clinical and histological observations of failed two-stage titanium alloy basket implants

This study presented an analysis of four failed implants removed from three human patients. The implants were in situ for 3 to 13 months and were removed due to pain, mobility, or infection, and fixed by immersion in 10% formalin. The specimens were embedded in PMMA, sectioned, and stained with basic fuchsin and toluidine blue. The specimens disclosed a coronal/apical variation of tissue responses. Apical sections of those implants with attached bone showed acceptable bone adaptation to the implant with little or no intervening connective tissue. As these sections progressed coronally, the intervening connective tissue widened, became loosely arranged, and aligned parallel to the implant surface. The most coronal aspect of the bone core showed necrosis, ulceration, and hemorrhage. It is speculated that trauma from insertion and failure of vascular regeneration may be the causes of failure.