Introduction
Gysi's orthognathic arrangement assumes jaws that relate normally (Angle Class I). Many edentulous patients don't: the jaws may relate as Class II or Class III, or resorption may make the lower arch wider than the upper. Then the teeth are arranged differently, always aiming for stability: teeth over the ridges, in the neutral zone, with balanced contacts.
Prognathic (Class II) arrangement
- Upper front teeth set to support the lip, with a larger overjet than normal; don't push the lower teeth forward off the ridge.
- Reduce the vertical overlap and flatten the guidance, so the dentures don't tip in protrusion.
- Back teeth set in normal buccolingual relation, sometimes with an extra premolar in the upper or one fewer in the lower to fit the arch lengths.
Progenic (Class III) arrangement
- Front teeth edge to edge, or with a slight reverse overlap, rather than forcing a normal overjet over unsupported ridges.
- Lower front teeth set more lingually, upper ones more labially, within the limits of lip support and stability.
- Back teeth often in cross-bite.