Histopathologic observation of seven removed endosseous dental implants.

Seven failed endosseous dental implants that were removed from humans were examined histologically. Results suggest that the hollow-basket portion or the vent should be located as far from the gingiva as possible, and that an adequate healing period is needed for implant placement following tooth extraction. In addition, findings also suggest that the hollow-basket implant is not suitable for a healing socket, that periodic inspection is necessary for two-stage implants to evaluate adaptation of the embedded junction between the abutment and implant in the gingiva, and that there is risk of coating separation from hydroxyapatite-coated implants and possibilities of coating resorption.