prostho 5 - still fail, some ortho thingy

I'm taking prostho 5 right now, and still failed taking impression...what the!

Obviously i need to study more and increase my memory capasity.

How does a good impression looks like?

Actually what we need from an impression is just the area which will be covered by the denture and few soft tissue areas which will affect masticatory functions and also soft tissues that will be touching the denture.

Usually in upper impression, impression should cover the functional depth of labial sulcus till beyond posterios border of hard palate, and laterally from functional depth of buccal sulcus of one side to the other side.

As for lower impression, impression should cover from the functional depth of labial sulcus till the retromolar pad and laterally from buccal sulcus to buccal sulcus of each side. Tongue should be protruded to the extent required to moisten the lips to make the impression with the floor of the mouth raised to functional position.

The position of the patient should be upright as to avoid patient choked by the material in used.

Impression trays
Selection of Stock Trays
Should cover :

-maxillary : entire alveolar ridge, maxillary tuberosities and both hamular notch, provide enough space for impression material

-mandibular : entire alveolar ridge, retromolar pad, should not be short in posterior lingual pouch area, tongue should not be trapped under lingual flange.

Modification of stock tray
- stock tray can be modified by addition of wax to the borders to ensure correct tray xtension (if alginate used)
-metal tray could be modified by using pliers to create space for impression material.

*believe it or not, these was what i've been questioning this morning and gosh, i got hampes-marks for i dont study. I only knew the answers this evening and grr!!


Ortho examination

1) Name, cc, MH
2) extraoral exm. : soft and hard tissue( profile, skeletal class, lower facial height, ricketts line(lip competence), frankfort line to ....angle)
2) intraoral exm.
- anterior posterior : overjet (eg:class 2 div 1)
- vertical : overbite
- transverse : presence of crossbite
3) treatment plan : removable appliance if not so severe, functional appliance if still growing, fix appliance if severe crowding and beyond growth time.