Evidence for a junctional epithelial attachment to ceramic dental implants. A transmission electron microscopic study.

The interface of the crevicular gingiva with the surface of a dental implant is a critical zone representing the potential biological seal which protects the underlying bone and soft tissue-supporting mechanisms from destructive extraneous substances. Ultrastructural examination of regenerated junctional epithelial cells interfacing surgically placed endosteal dental implants, comprised of alpha-alumina oxide ceramic in single crystalline form, exhibited an external basal lamina and linear body located between the external surface epithelial cell and the implant. In addition, hemidesmosomes were located at intervals along the outer junctional epithelial plasma membrane. The component substructures of the basal lamina and the hemidesmosomes were similar to those seen interfacing natural teeth. The linear body was an electron-dense structure between the lamina densa and the inert biomaterial. This study provides ultrastructural evidence for the presence of an attachment complex between gingiva and aluminum oxide implants which is analogous to that seen around natural teeth. These data support concept that a viable biological seal can develop around endosteal dental implants and provide support for satisfactory clinical service.