Advantages

• They are very durable, wear well and are retentive.

• The time for placement is fast compared to other techniques.

• They may be used when gingival hemorrhage or moisture is present or when the patient exhibits less than ideal cooperation.

• They are fairly inexpensive (approximately $6/crown).

Disadvantages

• Aesthetics are extremely poor. Some parents may opt for extractions in lieu of restoration of the teeth.

Advantages

• The aesthetics are fair. (The metal shows through the composite facing).

• They are very durable, wear well and retentive.

• The materials are fairly inexpensive.

Disadvantages

• The time for placement is long as it involves a two-step process (crown cementation / composite facing placement.

• Placement of the composite facing may be compromised when gingival hemorrhage or moisture is present or when the patient exhibits less than ideal cooperation.

• Anesthetize the teeth to be restored and place the rubber dam.

• Select a primary stainless steel crown with a mesio-distal incisal width equal to the tooth to be restored by placing the incisal edge of a stainless steel crown against the unprepared tooth.

• Remove decay with a medium to large round bur in a slow speed handpiece.  If pulp therapy is required, do it at this time.

• Using a 169L bur or a fine tapered diamond, reduce the incisal edge by 1.5mm.

• Reduce the facial surface by 1mm and the lingual surface by 0.5mm.  Create a feather-edge gingival margin.  Round all line angles.

• Try the pre-selected crown on the tooth.
   

• Anterior crowns are manufactured with an ovoid shape with a small facio-lingual dimension.  Change the shape to allow the crown to passively slip on the tooth.  Squeeze the crown slightly mesio-distally with a pair of Howe no. 110 pliers to increase the facio-lingual dimension.

• Reseat the crown.  The crown should extend 1mm under the gingival margin.  The fit of the crown should be snug without rocking.

• Trimming, if necessary, is best done with a heatless stone on a straight slow speed handpiece followed by polishing with a rubber point.

• Contouring and crimping are necessary to insure a good marginal fit.  Use a no. 137 Gordon plier to adapt the margin.  Check the marginal fit with an explorer.

• Seat and cement the crown.  Remove excess cement from the crown with a wet gauze.  The cement must be completely set before preparation and placement of the open faced veneer.

• Once the cement is set, cut a labial window in the cemented crown using a no. 330 or no. 35 bur.

• Extend the window:

  • Just short of the incisal edge

  • Gingivally to the height of the gingival crest

  • Mesio-distally to the line angles
     

• Using a no. 35 bur remove the cement to a depth of 1mm.

• Place undercuts at each margin with a no. 35 bur or with a no. ½ round bur

• Smooth the cut margins of the crown with a fine green stone or white finishing stone.

• After using a glass ionomer liner to mask differences in color between remaining tooth structure and cement place a layer of bonding agent.

• Place resin based composite into the cut window forcing the material into the undercuts and polymerize.

• Add additional material in 1mm increments and polymerize.

• Finish the restoration with abrasive disks.

• Run the disks from the resin to the metal at the margins so as not to discolor the resin with metal particles.

• Repeat the procedure for the remaining teeth.

• While more aesthetic than a conventional stainless steel crown, a shortcoming of an open faced stainless steel crown is the bleeding of the metal color from the lingual and interproximal surfaces through the composite resulting in a grayish tinge to the facing.