documents.pub_stainless-steel-crown-558490380b35e
                     Stainless Steel Crown
(SCC)
By;
 Mhmood Mohd.Hassan Radhi
BDS
final year
Introduction
• It is a semi-permanent restoration used 
in primary & young permanent teeth .
• It was introduced as chrome-steel 
crowns by Humphrey in 1950.
• Now it is commonly called as stainless 
steel crown.
• The stainless steel crown is used more 
frequently in deciduous dentition 
because of two reasons:-
 1st in a relatively small deciduous teeth 
neglected carious can destroy tooth’s 
integrity faster than in large teeth in 
permanent dentition.
 2nd the deciduous teeth pulp is larger 
than permanent pulp whereas the 
enamel and dentin is less in thickness, 
thus it is difficult to make dentinal 
stump for a gold casting or to use a pin 
system of retention for more extensive 
amalgam restoration.
Advantages
1. It has respect to life span, 
replacement, retention and resistance.
2. They are acceptable by both patient 
&dentist.
3. They are also more cost effective 
because of comparatively simple 
procedures in restoring.
Objective Of Using
 To achieve biological compatible 
,competent for mastication .
 To maintain the form and function and 
when possible the vitality of the teeth 
to be maintained .
Type
1. Untrimmed crowns: e.g. Rocky mountain
2. Pretrimmed crown: straight, non 
contoured sides but are festooned to follow 
a line parallel to the gingival crest, 
e.g. (Unitek stainless steel crowns, 3M Co., 
and Denvo crowns, Denvo Co. Arcadia, CA).
3. Precontoured crown : festooned and 
precontoured, (e.g. Ni-Chro Ion crowns and 
Unitek stainless steel crowns and 3M Co.).
Stainless Steel Crown
Composition
 Stainless Steel Crowns 
17-19% chromium 
10-13% nickel
67% iron
4% minor element 
• These crowns are available in various sizes.
• Mostly these crowns are used in posterior 
teeth which undergone pulp therapy.
 Nickel – base Crowns 
72% nickel
14%chromium 
6-10% Iron
0.04% carbon 
0.35% manganese 
0.2% silicon
• The alloys have good formability and 
ductility necessary for clinical adaptation of 
crowns and wear resistance to resist 
opposing occlusal forces.
Indication of SCC
1. Extensive decay in primary & young permanent 
teeth.
2. For teeth deformed by developmental defects or 
anomalies.
3. For teeth with hypoplastic defects.
4. Following pulp therapy.
5. As preventive restoration. 
6. As an abutment.
7. Temporary restoration of a fractured tooth.
8. In sever cases of bruxism.
9. Single tooth crossbite.
10. For replacing prematurely lost anterior teeth.
Factor to be considered in 
preoperative
1. Dental age of the patient. 
2. Cooperation of the patient.
3. Motivation of the parents. 
4. Medically compromised/disabled child.
Clinical Procedure 
 Evaluate the preoperative occlusion
• Take the alginate impression of U/L jaws.
• Pour the cast with dental stone
• Note the dental midline and the cusp fossa relationship 
bilaterally
 Selection of crown 
• The correct size crown is selected by the M-D 
dimensions of the tooth to be restored using 
Boley gauge.
• To produce steel crown margins of similar shape 
examine the contour of gingiva of the buccal & 
lingual marginal gingiva.
Tooth preparation 
 L.A. should be 
administrated
 Isolation by rubber 
dam or cotton rolls
 Remove the decay 
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 bur is moved B-L acrossthe 
proximal surface.
 Buccolingual reduction
 Round off all the line angles 
It is done by using side of bur.  

Initial adaptation of 
crown 
 Two principles related to SSC length and margin 
shape that are based on an understanding of the 
tooth morphology and gingival tissue contours were 
presented by Spedding 1984
 The crown should be of a correct length and its 
margins should be adapted closely to the tooth.
 For shaping the crown margins mark 3 light points on 
the metal at the (mesiolingual, lingual and 
distolingual)and at (mesiobuccal, buccal, distobuccal) 
surfaces at the crest of respective marginal gingiva 
without compressing the marginal gingiva.
 Final finished margins are placed approximately 1mm 
below these marks.
Seating the crown 
 Now the crown is tried on the preparation 
by seating the lingual first and applying 
pressure in a buccal direction so that the 
crown slides over the buccal surface into 
the gingival sulcus.
 Resistance should be felt as the crown 
slips over the buccal bulge.
Crown contouring 
 Initial crown contouring is 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
 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.
Crown contouring
Crown crimping
Checking the final adaptation of the 
crown
 The crown should be replaced on the 
preparation after the contouring  
procedure to see that it snaps securely 
into place.
 The occlusion should be checked at this 
stage to make sure that the crown is not 
opening the bite or causing a shifting of 
mandible into an undesirable relationship 
with opposing teeth.
Finishing and polishing
 Accumulation of plaque and inflammation 
of gingiva is commonly seen in practice of 
restorative dentistry due to rough and 
unpolished restoration.
 To avoid these complications crown 
should be polished prior t o cementation 
with rubber wheel to remove all 
scratches. 
Radiographic confirmation 
of the gingival fit
 Before cementation a bitewing is taken 
to verify proximal marginal integrity
Cementation 
 SSC should be cemented 
only on clean dry mouth, isolation of 
teeth with cotton roll is recommended.
 Rinse and dry the crown inside & out 
side and prepare to cement it.
 A zinc phosphate, polycarboxylate or 
GIC is preferred.
 Before the cements set ask the patient to close 
into centric occlusion by applying pressure 
through a cotton roll and confirm that the 
occlusion has not been altered.
 Remove the excess cement by an explorer or 
scaler & for interproximal area can be cleaned 
by passing dental floss through them. 
Result
special consideration for 
ssc
 Quadrant dentistry ( Nash, 1981)
-Prepare the occlusal reduction of one tooth completely 
before beginning the other as there is tendency to under 
reduce both when reduction on them is done at the same 
time.
-Reduce the adjacent proximal surface of the teeth being 
restored more than when only one tooth is restored.
-Both crown should be trimmed, contoured and prepared 
before cementation simultaneously to allow  for 
adjustment in inter proximal space and establish proper 
contact area.
 Crown in area of space loss(Mc - Evoy 1977)
 Preparing a SSC adjacent to a class II amalgam (Mc 
- Evoy 1985)
Stainless steel crown 
modifications
 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. 
Complications  
 Interproximal ledge.
 Crown tilt.
 Poor margins.
 Inhalation or ingestion of crown.
References 
 Shoba Tandon,  2nd edition 
 McDonald . Avery . Dean,  8th edition
Thank You