The presentation features the types, advantages, disadvantages, objectives, indications, contraindications, factors involved, clinical procedure, modifications and complications of Stainless Steel Crown.
1. Submitted by :
Jaya Nathani
Surabhi Nogariya
Department of Pedodontics
Govt. College of Dentistry, indore
2. Introduction
Advantages
Disadvantages
Objectives
Types
Indications
Contraindications
Factors To be considered in pre operative evaluation
Clinical Procedure
Modifications
Complications
References
3. Stainless steel crown is semi permanent restoration used in primary
and young permanent teeth
It was introduced as chrome-steel crown by ‘Humphrey’ in 1950.
Stainless steel crown is more frequently used in deciduous dentition
than permanent dentition because of two reasons.
1. In deciduous teeth caries can destroy the tooth faster than permanent
. 2. In deciduous tooth pulp is larger than permanent and enamel and
dentin thickness is less.
4. • The crowns are far superior to multi surface amalgam restorations
with respect to life span , replacement ,retention and resistance.
• They are acceptable to both patient and dentist.
• They are also more cost effective because of comparatively
simple procedures involved in restoring severely affected primary
molar.
6. To achieve biologically compatible , competent for mastication and
clinically acceptable restoration.
To maintain the form and function and where possible the vitality of
the tooth should be maintained.
7. Untrimmed crowns
Neither trimmed
Nor contoured
Require lot of adaptation and are time consuming
eg. rocky mountain
Pre-trimmed crowns
Straight non-contoured sides
festooned to follow a line parallel to the
gingival crest
Still require contouring and trimming
Eg. Unitek stainless steel crown
9. According to composition stainless steel crowns are of two
types
1.Austentic type
•Best corrosion resistance
•These crowns are available in various sizes.
•Mostly these crowns are used in posterior teeth which
undergone pulp therapy.
2.Nickel – base crowns
The alloys have good formability and ductility necessary for
clinical adaptation of crowns and wear resistance to resist
opposing occlusal forces.
10. Extensive decay in primary & young permanent teeth.
For teeth deformed by developmental defects or
anomalies.
For teeth with hypoplastic defects.
Following pulp therapy.
As preventive restoration.
As an abutment.
Temporary restoration of a fractured tooth.
In severe cases of bruxism.
For replacing prematurely lost anterior teeth
Single tooth crossbite.
11. If the primary molar is close to exfoliation with more than half
the roots resorbed or exfoliation within 6-12 months
Clinical or radiological evidence of radicular pathology
Tooth exhibits excessive mobility
Partially erupted teeth
Where conservative restorations can be placed
In a patient with a known nickel allergy
12. 1. Dental age of the patient.
2. Cooperation of the patient.
3. Motivation of the parents.
4. Medically compromised/disabled child.
13. Evaluate the preoperative occlusion
• Evaluate the cast for the dental midline and the cusp fossa relationship
bilaterally
Selection of crown
3 main considerations-
• Mesiodistal diameter
• Proper gingival contour
• Proper occlusal height
Tooth Preparation
• LA should be administered
Isolation
• Using rubber dam and cotton rolls
Removal of decay
14. Reduction
Occlusal reduction
A 69L or 169L bur is used to reduce the occlusal surface
by 1.5-2.0mm .
Proximal slices
place the wooden wedges in the interproximal
embrasures, the 69L or 169L bur is moved B-L across the
proximal surface.
Buccolingual reduction
Reduction is minimal
Round off all the line angles
It is done by using side of bur
Initial adaptation of crown
The crown should be of correct length and margins
should be adapted closely to the tooth
Seating the crown
Crown is tried on preparation by seating lingual first
Resistance should be felt as the crown slips over buccal
bulge
15. Crown contouring
Performed with a 114 plier in the middle 1/3rd of the crown to
produce a belling effect.
This will give the crown a more even curvature.
Crown crimping
Done with Unitek 800-412 pliers
The tight marginal fit aids in:
1. Mechanical retention of the crown.
2. Maintenance of gingival health.
3. Protect of cement from exposure to oral fluids.
Checking the final adaptation of the crown
The crown should snaps securely into place.
Occlusion should be checked
Finishing and polishing
The crown should be polished prior to cementation with
rubber wheel to remove all scratches.
16. Radiographic confirmation of the gingival
fit
Before cementation a bitewing is taken to verify proximal
marginal integrity
Cementation
A zinc phosphate, polycarboxylate or GIC is preferred.
18. In 1971, Mink & Hill report several way of
modifying the SSC when they are either too large
or too small
1. Undersize tooth or the oversize crown.
2. Oversize tooth or undersize crown.
3. Deep subgingival caries.
4. Open contact.
5. Open-faced stainless steel crown.