Histologic Observations of Two Dental Implants Retrieved After Osseointegration

This study aimed to histologically analyze the bony tissue formed around dental implants after osseointegration. A 58-year-old patient presented with pain and discomfort caused by two dental implants in her maxilla placed 8 months earlier. At clinical and radiographic analysis, the implants appeared well osseointegrated but tilted buccally, emerging in nonkeratinized mucosa. For this reason, the discomfort began right after the prosthetic load, 4 months after implant placement, and the patient felt pain when wearing the implant-supported removable prosthesis. Both implants were made of titanium, airborne-particle abraded with zirconium oxide, and etched with mineral acids. The implants were removed, preserving the bone around the implant threads, and replaced with two new implants, inserted in a prosthetically guided, correct position. The removed implants were histologically observed. Histologic analysis showed good bone-to-implant contact, mature bone with few marrow spaces, presence of direct connecting bridges between the peri-implant bone trabeculae and the implant surface, and no inflammatory cells nor connective fibrous tissue ingrowth. This study showed that dental implants coated with a rough surface were properly osseointegrated, with no inflammatory signs nor connective fibrous tissue ingrowth, 8 months after placement.