Indications:

Where patient would otherwise suffer tooth loss or even full extraction.
Traditional cast partial cases where undercuts in part of the oral anatomy will not allow hard denture base and clasp adaptation.
Where several natural teeth worth saving remain but these teeth are not strong enough to support cast frameworks.
Where the path of insertion is a problem.
In situations where cross arch stabilization would otherwise be difficult or impossible to achieve.
When conventional clasping is not a viable option (i.e. remaining teeth very short with no buccal undercut).
While can be prescribed as either an upper or lower partial, works best in mandibular application.

Contraindications:

Patients who, through poor oral hygiene, build up plaque at the gingival margins.
Cases of severe tooth angulation where insertion is extremely difficult and a lack of proper undercuts lead to food entrapment.

Preparation:

In some instances, straightening and/or paralleling of remaining teeth may be advisable. Any teeth naturally out of line should be reshaped into improved alignment.
Determine whether the appliance should be tissue or tooth borne. The extraction of one or more mobile teeth may make the patient a more viable candidate for a Virginia Partial.
In maxillary applications, when the frenal attachment is very close to the cervical of the tooth, a frenectomy may be considered. This eliminates the V-cut that would be necessary to clear the frenal attachment (greatly weakens the Virginia Partial).
Any sharp incisal edges which may come in contact with the elastic retainer band should be rounded off prior to insertion.
Where there are large tori on the lingual of the teeth, a cast lingual plate should be prescribed in combination with the soft retainer band on the anterior teeth.
Second molars on the upper and lower do not lend themselves to the Virginia Partial due to the short space distal to these teeth plus the short space between the tuberosity and retromolar pad. A wrought wire or Aker’s clasp is recommended in this situation.

Checklist for Alginate Impressions

The following is a general set of steps and tips regarding taking an alginate impression.

Select the proper tray. A non-perforated rim-lock tray is recommended with most alginates for impressions of partially edentulous patients.
Modify the selected tray rimming periphery wax or heavy-bodied polyvinyl siloxane impression material around the entire upper and lower trays. Seat trays in the mouth and muscle trim prior to placing impression material.
Clean teeth and prepare mouth as necessary. For regular-bodied alginates, it is generally best to have the patient rinse with a mouthwash mixture. This will cut the mucin and lower the surface tension helping to eliminate air bubbles. For heavy-bodied alginates, saliva makes an excellent separating medium.
Place gauze in the mouth to remove excess saliva, if necessary.
Mix pre-weighed alginate and precisely measured distilled water for 15 seconds if a vacuum mechanical mixer is employed or 60 seconds with hand spatulation (timed with a clock).
Dip the tray in water to wet the cotton fibres and blow excess water away with air.
Load the tray, being careful to force the alginate into the rim-locks.
Remove any gauze from the mouth.
Gently place some alginate on the teeth and in the palate.
Seat the tray immediately with a slight rocking motion. Do not force the tray into contact with the teeth.
When the tray is seated, release the pressure and hold the tray lightly in place to prevent its unseating.
Place a small amount of the alginate mix on the bracket table as a test sample.
When the test sample has lost its tackiness, set a timer for two minutes.
At the end of the two minutes, remove the impression with a firm, quick snap.
Inspect the impression carefully for defects as soon as it is removed and before it is washed.

Pouring the Model

All alginate impressions should be poured immediately using vacuum mixed stone and a vibrator.
A soft mix of stone should be used. A thick mix is apt to trap air bubbles and does not provide the same strength upon setting.
Allow the stone to set in the trays with the teeth down.
If the tray is turned upside down onto a base of stone, there is a tendency for water to rise to the highest point, in this case, the cusp tips. The result would be faulty, very soft cusps on the model. Inverting the tray may also tend to “bend” the alginate away from the tray if excess material was not trimmed away prior to pouring.
Remove cast immediately after it has an adequate set or ensure alginic acid is neutralized. All alginate materials contain alginic acid. If left in contact with stone for an extended time, this acid will give the model a “moth-eaten” appearance. To neutralize the alginic acid at the surface of the impression:

Wash the impression with “stone soup” (some stone powder and water) using a camel's hair brush.
Thoroughly rinse the impression with clean running water.
Dry with a gentle stream of compressed air.
Pour impression immediately with a soft mix of vacuum mixed stone.

Chairside Adjustments:

If the flexible band is too long, shorten to proper length and smooth using a Molloplast-bur (available from Cerum Dental Supplies Ltd.). These burs have a special cross-cut design perfectly suited for Virginia Partial adjustments.
To thin the band, support the tissue side of the partial and gently remove the excess material with a Molloplast-bur.
Tissue side adjustments should be made using a large rough diamond bur on a high-speed handpiece.

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