A series of screws go through the bottom of the front part of the jaw. The screws attach to a plate on the top of the jaw bone and two attachments protrude above the gum for stabilization of a prosthesis.

Provide excellent stability through bicortical stabilization

Only indicated for anterior mandible. Requires an extra-oral approach (an incision is made under the chin).

None

Prosthetic abutments are very limited and abutments may not be in the position that we would want for ideal tooth placement. Only useful for mandibular overdentures.

These implants are difficult and costly to manufacture. I believe there is only one source for these implants. They are very expensive.

This is basically an inferior category and has no indication today. Not recommended!