Recently updated on January 8th, 2020

Crowns
Unlike veneer, a crown covers the entire tooth and restore lost anatomical shape, function and aesthetics.
When do I require a crown?

Crown is recommended in the following cases:

1. Damaged tooth.
2. Heavily restored tooth.
3. Dysplastic tooth.
4. Worn tooth.

Types of crowns

All Porcelain and All Ceramic Crowns
Growing demand in aesthetics is a major factor which is driving the manufacturers to develop all-ceramic materials which provide outstanding aesthetics and also offer high strength. One of the revolutions has been the shift from Porcelain fused metal restorations to all-ceramic restorations
[1] Feldspathic Porcelain crown
These are traditional crowns and are aesthetically very appealing and very beautiful.
[2] Empress crown
Also called ceramic crowns and looks like glass. It is not baked like Feldspathic porcelain crown but cast and it fits more precisely than the feldspathic crown. Both empress and feldspathic crowns give excellent aesthetic results.
[3] Procera crown
These crowns have a ceramic core which is milled and the technician will layer the porcelain on the outside. This crown is very strong but the core is opaque and not natural looking. This crown is cemented directly on to the tooth.
[4] Lava crown

Translucent Zirconia is used as core material and an outer layer is baked for better aesthetics. This crown can be cemented directly instead of bonding.

[5] Zirconium crown
They are the strongest among dental crowns. There is solid zirconia which is tougher than high translucent zirconia and can withstand forces in the mouth better and is used in the root canal treated teeth and posterior teeth. High translucent zirconia is more suited for anterior teeth due to its better aesthetic looks and high strength compared to porcelain fused metal crowns or bridges. Zirconium metal is 100% biocompatible. Once the crown is milled, colouring to the crown may be added and sintered and glazed. These crowns can be cemented using traditional cement.
[6] IPS-Emax Crowns
Emax crowns are made from lithium disilicate glass ceramic and it can be considered as one of the materials of choice available for dentists and dental technicians for its high translucency which is similar to natural teeth and, at the same time it offers flexible strength of up to 400 MPa, which is almost three times as high as traditional glass-ceramic. The durability of lithium disilicate material fulfils the standards of a veneering material and it can be used for monolithic restorations and can be either cemented conventionally or adhesively bonded. These crowns are very popular.
After care instructions

[1] Routine oral hygiene care should be followed including using floss and interdental toothbrushes where required.

[2] Need to visit hygienist regularly to maintain good oral hygiene.

Advantages of All-Porcelain and All-Ceramic crowns
[1] Appealing aesthetics.
[2] Highly compatible and no allergies.
[3] Some ceramics are very tough and fracture resistant.
[4] No unsightly metal margins like Porcelain fused to metal (PFM).
Disadvantages of All-Porcelain and All-Ceramic crowns
[1] All-Porcelain crown is not as strong as PFM.
[2] All–Ceramic crowns need more tooth reduction to accommodate ceramic core and porcelain which is not desirable.
[3] As some ceramics are tough and fracture resistant, they can be quite abrasive against the teeth present in the opposing arch.

Porcelain fused to metal crowns (PFM)

PFM crowns have been the first choice for many years to restore the damaged and diseased teeth and these crowns are more affordable. These crowns have a metal shell (core or substructure) and 1.5mm to 2m layers of porcelain is fused over this core to give the shape and colour. The metal framework (core) is very strong and it is a combination of different alloys. The porcelain layer can withstand the chewing forces exerted in the mouth.
Types of PFM’s
1. Porcelain fused to base metal alloys.
2. Porcelain fused to gold alloys.
3. Porcelain fused to titanium alloys.
Advantages of PFM
1. Very strong and durable.
2. The high rate of success in the long run.
3. Very stable.
Disadvantages of PFM’s

1. Cannot truly mimic the look of a natural tooth and does not give a perfect smile.
2. Metal margins are visible if gums recede and look unsightly especially in the anterior region.
3. Needs a lot of tooth reduction to accommodate the metal substructure and porcelain.

4. Can cause gingivitis if the margins are not placed properly.

Our Info

Claremont Dental Practice,

1-3 Terminus Buildings,

Claremont Road,BN25 1NT

Tel: 01323 897502

E-mail: cd@claremontdental.org

© 2020 Claremont Dental Practice.