The zero degree anatomic teeth is used in:
Monoplane Occlusion

Cuspless teeth (0o) on a flat plane with 1.5-2.0 mm overjet.
No cusp to fossa relationship
No anterior contacts in centric position
Poor residual ridges
Poor neuromuscular control (Bruxers, CP, etc.,)
Previously successful with monoplane dentures or severely worn occlusion on the previous denture
Arch discrepancies
	- Class II or III or Cross-bite
Immediate Dentures
	- Except when opposing natural dentition
Potential poor follow-up.
Sharp ridge
Flat ridge
Ridge with undercut
Well contoured ridge