|
FINAL IMPRESSION TRAYS |
|
| Grade A | Tray handles are occlusion rim type supporting the lips and cheeks properly. Tray trimmed 2-3 mm short of vestibule on preliminary cast. Borders should be well adapted to vestibule on preliminary cast. Borders should be well adapted to the cast and smoothly formed with no sharp projections. Handles should be 5-7 mm wide in the molar region tapering to 3-5 mm wide in the incisor region. The handle should be approximately 22 mm in length from the highest point of the labial flange to the incisal edge in the maxillary arch and 15-18 mm in the mandibular arch. The mandibular handle should terminated 8-10 mm from the distal of the final impression tray. Palate of the tray is closely adapted to the cast. Tray should cover the tuberosities or retromolar pads. |
| Grade B | Tray and/or handle have minor variations from above which would not affect quality of final impression. |
| Grade C | Tray is adequate to make a clinically acceptable impression, but marginally so. Tray more than 1-2 mm overextended or underextended. Tray is rough, has sharp edges, has residual blockout wax not removed, is 3-4 mm thick in areas and/or not uniform in thickness. Tray handles not positioned properly in relation to ridges, more than 2 mm off of measurements shown and/or not finished neat and clean. |
| Grade E | Tray prevents clinically acceptable impression. Tray more than 3-5 mm overextended or underextended. Tray is very rough, has numerous sharp edges, residual blockout wax and other debris not removed, is 5-7 mm thick in areas, or so thin tray integrity is compromised. Tray handles not positioned properly in relation to ridges, distort the lips, are more than 3-4 mm off of measurements shown and/or not finished neat and clean |