This case report demonstrates long-term implant stability associated with focal cemento-osseous dysplasia (FCOD). The nature of the cementum-like tissue (CLT) of FCOD around the titanium surface of the implant is described clinically, radiologically, and histologically. A dental implant placed directly into the FCOD lesion was successfully integrated, and the stability was maintained for 15 years. However, at the 16-year follow-up, the implant and a sclerotic mass were removed due to peri-implantitis, and the entire specimen was evaluated with conventional histology and microcomputed tomography. The analysis revealed that the sclerotic mass attached to the implant was CLT that was free of any intervening soft tissue. The implant placed into the FCOD lesion achieved integration similar to that of conventional osseointegration. Rather than bone, the CLT was in direct contact with the titanium surface. The integrity of the union was maintained for up to 16 years.