stainless steel crowns (sscs)

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Stainless steel crowns (SSCs)

Stainless steel crown

Prefabricated crown forms adapted to individual teeth & cemented with a biocompatible luting agent.

Also called preformed metal crowns (PMCs).

Chrome steel crown.

Stainless steel crowns

SSC Type :

• Straight untrimmed:longer than average tooth, require trimming and contouring

• Precontoured crown:Festooned and precontoured

• Pretrimmed crown:No contoured, but festooned to follow gingival crest line

Advantages:

Extremely durable.

Relatively inexpensive.

Subject to minimal technique sensitivity during placement.

Full coronal coverage.

Used to preserve1ry teeth till exfoliation.

Used as semi-perm. restoration for perm.

Stainless steel crowns

Indications:

Restore primary or young permanent tooth with extensive caries lesion

Restore primary tooth following pulpotomyor pulpectomy procedure

Restore hypoplastic primary or permanent tooth

Restore teeth with hereditary anomalies such as dentinogenesis or amelogenesisimperfecta

Indications of SSC

As an abutment for space maintainer or prosthetic appliances

restoration of a fractured tooth.Failure of other restorative materials is likely ( e.g. interproximal caries extending beyond line angles)

In children with bruxism.

Armamentarium

Crown cutting scissors

Adams pliers

Contouring plier (Johnson 114)

Crimping pliers (Unitek 800-108)

Stainless Steel Crowns Preparation

Preoperative occlusion evaluation

Occlusal reduction (1-1,5mm)

Proximal reduction

B/L bevel and roundation of all angels

1. Rubber dam Application

To protect surrounding tissues. To improve visibility and efficiency.To better manage behavior.To prevent ingestion of the stainless steel crown during preparation.

Reduction of occlusal height

A large flat diamond bur or diamond stone is used to reduce cusps, following the occlusal anatomy until the tooth is completely out of occlusion.

Reduction of occlusal height

For beginners, it is advisable to cut a groove into the fissures and then reduce the height of the crown to that level using carbide bur

The tooth is completely out of occlusion and there is room to fit the

If a rubber dam is used it is useful to use the occlusal table of the crown. Of adjacent tooth

Reduction of mesial and distal surfaces

Finish line is a feather edge.

Extend the slice to the buccal and lingual line angles.

Reduction of mesial and distal surfaces cont.

Leave tooth structure proximal to the bur when it is being removed

Gingival step or ledge which would prevent seating of the crown.from buccal to lingual

The preparation should be extended gingivally to remove the ledge

Round-off sharp edges and make a final check of the preparation

There should be adequate occlusal and proximal clearance without any

The completed preparationledges proximally as seen on the mesio-distal section

Selection and adjustment of the SSC

Adequate M/D diameter

Light resistance to seating

Proper occlusal height, and occlusogingival crown length

114 ball and socket pliers used only at the cervical third of the B/L surface

112 ball and socket pliers used to produce contact

Crimping with 800-417 pliers

Stainless Steel CrownsImportance of tight marginal fit:

Mechanical retention of the crown

Protection of the cement from exposure to oral fluids

Maintenance of gingival health

Crimping of crown margins cont.

Crown cementation

The crown should be filled with polycarboxylate cement and handed to the dentist on the fingertip

Crown cementation cont.

The crown is seated onto the tooth on the lingual side first and

The child is instructed to bite the teeth together.

If two adjacent teeth are lingual side first and then pushed over onto the buccal side.being restored, then both crowns are seated at the same time.

Removal of excess cement

When cement sets the excess can be flaked away using a suitable

A piece of dental floss is passed backwards and forwards through the instrument.gingival embrasures to remove the excess cement.

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