Bone changes incident to blade-vent implants

This research was undertaken to study the dynamics of bone changes in relation to endosseous blade-vent implants with vital labeling technique. Three mandibular premolars were bilaterally extracted in six two years old dogs. Subsequently each healed edentulous space was implanted with a titanium endosteal blade. One blade in each dog had the post extending into the mouth; the other had the post cut at the level of the neck and covered by the mucoperiosteal flap. The animals received I.V. Pyrrolidin-Methyl-Tetracycline and Alizarine Red S labelings at 15 and 30 days intervals. Dogs 1, 3 and 5 were sacrificed on the 97th day; dogs 2, 4 and 6 on the 52nd day. On ground sections of the mandibular bone which included the blades under U.V. light, it was observed that the implants were surrounded by remodeled trabecular bone of cancellous nature containing the labeling lines of Tetracycline (yellow) and Alizarine (red). The bone-metal interface consisted mainly of a thick layer of non mineralized tissue of about 70 micrometer. The labeling results showed that the new bone apposition began early (at least by the 15th day) and continued for a long time, being still present at the moment of the last injection (90th day). No difference was recognized between the bone responses to the implants jutting out and those submerged. This confirms that implant failure is mainly linked to irregular traumatism and inflammatory infiltration which occurs over a more prolonged duration.