The great advantage of the pterygoid implant over the conventional subperiosteal implant is that the forces brought to bear over the protruding pontics are not distributed directly to the weakened underlying base. Instead the forces are dissipated from the pontics to the horizontal Andrews bar to be directed menially and distally to the denser bone anteriorly and posteriorly that exists in the pterygoid area.

My current philosophies have reduced the pterygoid extension implant into one basic design for the totally edentulous maxilla and for the partially edentulous maxilla.

For the totally edentulous cases we always incorporate into the design support from beneath the anterior nasal spine, both pterygoid processes, a continuous palatal strut all along the palatal side of the alveolar crest just before it blends in with the hard palate, but not including the palate (40). Anteriorly two cross over struts cross over the alveolar bone in both cuspid regions to act as the anterior support for a horizontal beam on each side of the arch bearing three or four female inter-coronal (I-C) attachments and posteriorly a tuber strut resting beneath the tuberosity and distal to the sinus to act as the posterior support for both horizontal beams. (41, 42, 43, 44) Figs. 45 thru 50 show healed tissue site around six more pterygoid extension implants.

The partial pterygoid extension implant (51) design is exactly the same except an anterior figure eight locking device is most usually used.

130