POSTERIOR PALATAL SEAL ON MASTER CAST

Grade A Outline of posterior palatal seal neatly carved to correct position and size.  Extends about 3 mm lateral to pterygomaxillary notches.  Narrows in midline area.  On average 2-3 mm in width in midline, 2 mm in width at pterygomaxillary notches and 4-6 mm wide in between.  Depth of seal is in the range of 1.0-1.5 mm deep except in the pterygomaxillary notch area where depth is slightly less.
Grade B Minor discrepancies from above which do not compromise the quality of the clinical treatment.  Outline of posterior palatal seal neatly carved, and correctly positioned.  Size and/or shape slightly out of norm. Slightly rough or irregular.
Grade C Posterior palatal seal carved in master cast is adequate to make a clinically acceptable complete denture, but marginally so.  Indelible marker ink spread out making markings somewhat indistinct.  Standard shape of "ideal" posterior palatal seal present.  Depth deviates significantly from above.
Grade E Posterior palatal seal prevents clinically acceptable complete denture treatment.  Posterior palatal seal absent or is grossly indistinct, ill-shaped or sized.  Excessive or inadequate depth into master cast.  Does not extend into buccal vestibule.  located much too far posteriorly or anteriorly relative to the structures used for reference.