PATIENT VISIT 2– FINAL IMPRESSIONS
Clinical Procedures

Evaluation and Correction of Final Impression Trays

Maxillary
1. Place the maxillary tray in the patient's mouth and retain it with the index finger of one hand in the palatal portion of the tray.  Gently reflect the lips outward and downward.  If the tray is overextended, it will be displaced, and you will feel this with your index finger in the palate.
2. Gently reflect the cheek on the right outward and downward.  Any overextension will again be felt by the displacement of the tray.  Reverse hands and reflect the left check outward and downward. 
3. Relieve the tray borders with suitable  burs, if necessary.

Checklist for Maxillary Final Impression Tray

1. Extend to junction of hard and soft palate (vibrating line)
2. Extend into pterygomaxillary notches (hamular notches)
3. Cover maxillary tuberosities
4. Extend into buccal and labial vestibules
5. Provide relief for labial and buccal frena
6. Be neat, clean and free of sharp or rough areas

Mandibular
1. Place the mandibular tray in the patient's mouth and stabilize it with the index and middle fingers of one hand placed on the handle in the right and left premolar regions.  Using the other hand, gently reflect the lip and the right and left cheeks outward and upward.  Overextension can be noted from displacement of the tray and observation of the tray displacing the mucosa.
2. Ask the patient to place the tip of the tongue in the corner of the mouth, first on one side and then on the other side.  If tongue movements disturb the tray, the tray is overextended.  Before you relieve the distolingual flanges, be certain that the tray is not overextended in the sublingual crescent area and over the sublingual glands. 
3. Ask the patient to lick the upper lip from one side too the other.  Overextension of the lingual frenum will cause the tray to dislodge. 
4. Adjust any overextended areas with suitable burs and stones.  Reevaluate adjusted areas in the patient's mouth.
5. Check the mentalis (labial flange) and masseter muscle region and relieve tray borders if overextended when muscles are activated.

Checklist for Mandibular Final Impression Tray

1. Cover retromolar pads
2. Extend to external oblique ridge
3. Extend into retromylohyoid space
4. Extend into alveololingual sulcus
5. Be neat, clean and free of sharp areas