- To restore the anatomy and function of the tooth
- To preserve the tooth and prevent complications
- To control pain
- To prevent early loss of deciduous teeth that may result in
alignment problem in the permanent teeth
|
1. Amalgam
Amalgam has been used as a dental filling material for more
than 150 years.
Composition: An alloy of mainly silver, tin, copper and mercury
Properties
- Hard and durable; high wear resistance
- Easy to use
- Safe
|
Amalgam safety:
The followings are some queries about amalgam:
-
Mercury, which is poisonous, is used in
dental amalgam. Is amalgam filling safe?
Amalgam contains various metals such as silver, copper and tin,
as well as mercury. When mercury is combined with these metals,
it becomes an inactive stable substance. Only under unusually
great pressure or abrasion will the amalgam release a minute
amount of mercury vapour. As compared to the daily dosage of
mercury being absorbed from the environment, such as food, water
and air, the minuscule amount of mercury released from the amalgam
fillings is insignificant.
|
Disadvantag:
The greyish-silver colour of amalgam is not aesthetically appealing.
Application:
It's mainly used for restoring back teeth where stress load is high.
Procedures for amalgam filling:
- First remove decayed tooth substances
- Amalgam is placed into the tooth cavity
- The filling is shaped, excessive material is trimmed off and
the filling is polished
|
2. Composite
It has been in use for over 40 years and has been undergoing improvement
in the past 10 years.
Composition
A substance made up of acrylic resin filled with inorganic substances
such as glass, quartz as additives to enhance the strength
Properties
Aesthetic; colour is similar to natural tooth, but will be stained by
food colour after having been in use for a period of time
Disadvantage
Not as hard as amalgam
Application
- To restore decayed teeth
- To restore the aesthetics of the teeth, such as to modify the
shape, size and colour of the teeth
|
Procedures for composite filling
- Decayed or weakened portion of the tooth is removed
- Tooth surface is etched with diluted acid (for example, 30%
phosphoric acid)
- Tooth adhesive is applied on the prepared tooth
- Composite is placed onto the prepared tooth and the restoration
is shaped
- Filling is hardened by using a light curing instrument
- Excessive material is trimmed off and the restoration is polished
|
3. Glass Ionomer Cement
It has been in use for over 20 years and has been improved in
recent years.
Composite： A substance is made up of aluminosilicate
glass powder and a liquid polyacrylic acid
Properties
- Aesthetic; colour is similar to natural tooth, but lack of
translucency
- Bonds to the tooth
- Fluoride releasing — prevents recurrent Dental Caries around
the filling material
|
Disadvantage：Inadequate strength, low wear resistance,
not durable
Application
- To restore abraded teeth
- Because it is not durable, it serves as a transitional filling
for deciduous teeth
|
Procedures for Glass Ionomer Cement filling:
- Decay is removed
- Glass ionomer cement is placed onto the prepared tooth and the
restoration is shaped
- Filling is hardened by a light curing instrument
- Excessive material is trimmed off and the restoration is polished
|
4. Compomer
A newly developed material in recent years
Composition ： It is a mixture of composite and glass
ionomer cement.
Properties
Application
- Used as transitional filling for deciduous dentition
|
Procedures for Compomer filling
- Decay is removed
- Tooth adhesive is placed on the prepared tooth
- Compomer is placed onto the prepared tooth and the restoration
is shaped
- Filling is hardened by using a light curing instrument
- Excessive material is trimmed off and the restoration is polished
|
5. Stainless Steel Crown
Silver in colour, fixed sizes, and usually used for molars of deciduous
teeth
Procedures for stainless steel crown
- A thin layer of the tooth is removed.
- The stainless steel crown with the right size that fits the
tooth most is chosen.
- The crown is then trimmed according to the contour of the tooth.
- The tooth surface is cleaned.
- The crown is cemented onto the tooth.
|
Generally speaking, it may take several days to one
week's time to get used to the new filling. Since decayed tooth structure
is removed during the filling process, the tooth may become more sensitive.
The discomfort should subside as time goes by. If the situation doesn't
improve or even worsens, you should see a dentist to seek for a detailed
check-up.
A. Purpose
- To restore a fractured tooth
- To build up an unusually small tooth to improve appearance
- To close an interdental space by building up the two adjacent teeth
- To cover a discoloured tooth
1. Composite
2. Porcelain
Properties
- Aesthetic — the colour and translucency can match the natural
teeth
- The material is not easily stained
- Hard and high in wear resistance
|
Disadvantage
- Brittle and suitable for non-stress bearing area only
- Certain thickness of tooth substance has to be removed in order
to provide enough bulk of the material
|
Application
- Tooth veneer or crown
- To restore teeth with high aesthetic requirement, especially
the front teeth
|
Procedures for porcelain laminate veneer
- A thin layer of tooth substance is removed from the facial
surface of the tooth.
- Impressions of the upper and lower teeth are taken and the
bite registration is recorded.
- The veneer is fabricated in the dental laboratory.
- Tooth surface is cleaned before cementing the veneer.
- Tooth surface is etched and treated with diluted acid such
as 30% phosphoric acid.
- The veneer is cemented onto the tooth.
|
| |
Procedures for porcelain crown
|