1. Anesthetize area if indicated.
2. Take preliminary impression.
3. Select gingival, body and incisal shades of teeth to be restored (NOTE: Best accomplished after old amalgam is removed).
4. If near pulp exposure, place small amount of calcium hydroxide in deepest area of preparation.
5. Prepare teeth as follows:
   • On posterior teeth, except where esthetic results are important, a metal gingival collar is suggested. This is more hygienic and also kinder to the periodontal membrane by creating a smoother transition from tooth to crown. Margins can also be burnished closed in the event a minor discrepancy should occur.
   • Ensure crown preparation has sufficient reduction (suggested minimum 1.5 - 2.0 mm) for a strong and beautiful porcelain occlusal surface.
   • Ensure a minimum labial reduction of 1.5 mm (insufficient labial reduction can cause poor translucency, bucked centrals and angry patients).
   • For a porcelain to margin finish, prepare a chamfered shoulder .5 mm sub-gingivally on the labial aspect of the tooth. Tissue must be retracted during impression so that the resultant die is a complete reflection of the prepared shoulder.
   • For superior esthetics, you may wish to select a PORCELAIN BUTT MARGIN (combines strength of PFM crown with esthetics of complete porcelain labial margin). Eliminates shadow effect due to underlying metal substructure showing through thin, friable soft tissue at gingival margin or exposure of metal collar due to gingival recession. End lingual metal collar midproximally (particular case situations may dictate other locations), labial metal is cast only to axiogingival line angle. Porcelain margin should be finished with either a 90-degree or sloped shoulder while lingual metal margin should be prepared with a chamfer or shoulder bevel.
   • Ensure there is an adequate path of insertion.


6. Take final impression with Panasil vinyl polysiloxane impression material.
7. Secure and trim an adequate interocclusal record (Regisil or similar material).
8. Cement temporary restoration.
9. Prepare detailed lab prescription with details re: opposing teeth, age and sex of the patient, amount of occlusal staining required, and individual characterization needed.

Facial, lingual and proximal surfaces may be reduced a minimum of 1.0-1.5 mm. Incisal or occlusal reduction should allow for no less than 2 mm porcelain in final restoration.

Create a shoulder (preferred) or a deep chamfer with rounded gingivo-axial line angles. Extend wherever a porcelain margin is desired. Be sure to carry the margin interproximally to reduce metal shadow and ensure esthetic quality.

Must be adequate reduction to provide room for metal and porcelain for strength and esthetics. Surfaces of prepared teeth should be smooth and rounded with no sharp line angles. This will facilitate proper seating, reduce stress concentration and help avoid porcelain fractures.

Porcelain margins on knife edge or feather edge preparations are not recommended, as the thin porcelain offers no strength and poor marginal integrity.