What are stainless steel crowns??
- These are prefabricated crown forms that are adapted to individual teeth and cemented with a biocompatible luting agent . Hence, stainless steel crowns have become popular in rehabilitation of grossly lost tooth structure in primary young permanent teeth.
- It was introduced as chrome-steel crown by Humphrey and Engel in 1950 ; with significantly improved crowns by Unitek in 1960s. A number of literature researches have been carried out and the results however were in favor that stainless steel crowns are superior to amalgam restorations for multi-surface cavities in primary molar teeth.
- The following article will make an attempt to enlighten the indications, contraindications, composition,advantages, disadvantages, and techniques for use of stainless steel crowns.
When are stainless steel crowns given??
- Extensive caries
- Extensive decalcification
- Rampant caries
- Recurrent caries
- Following pulp therapy
- Inherited or acquired enamel defects. Eg:- hypoplasia, amelogenesis imperfecta
- Severe bruxism
- As an intermediate restoration
- As a part of space maintainers
- In children with high caries rate
- As an abutment teeth to prosthesis
- In case of fractured young permanent teeth
When are stainless steel crowns not given??
- Primary molars close to exfoliation
- Molars with more than half the roots resorbed
- Mobile teeth
- Teeth that are not restorable
- Patients with known nickel allergy
Why are stainless steel crowns used ??
- Very durable and less prone to fracture
- Cost effective and comfortable to the patient
- Protects and supports the remaining tooth structure
- Can be completed in a single appointment
- No need for laboratory procedures
- Less time consuming than cast restorations
Risks in the use of stainless steel crowns.
- Significant amount of tooth structure is removed
- Poor marginal adaptation may cause gingivitis
- Gingival inflammation due to excess unremoved cement
- Requires patient co-operation
- Cannot be used in case of nickel allergy
How to use stainless steel crowns? (Procedure)
- Select an appropriate size crown.
- Local anesthesia and isolation.
- Occlusal reduction of 1.0 - 1.5 mm.
- Proximal reduction to establish 2 to 5 degree taper.
- Reduce and round of all line angles.
- Trial fit- Festooning
- No more than 1 mm of crown should be sub-gingival; so trim the excess with scissors and smoothen the edges.
- Cement with glass ionomer cement. Seat the lingual aspect first.
- Allow to set. Remove the excess.
- Polish the crown with acidulated phosphate fluoride prophylaxis paste.