Tetracycline
(antibiotic)
Enamel hypoplasia (white spots defects in tooth enamel)
Fluorosis (stains excess fluorine)
There are also those that appear after the eruption of the teeth as a result
of:
Blows or fractures in the teeth
Aging of the tooth. (an older person's teeth are more yellow or opaque)
Among extrinsic pigmentations (or coming by ingestion of food or beverages)
are:
Tea
Coffee
Snuff (tar and nicotine)
Mate
Wine and cola drinks consumed in excess
Pastes and Whitestrips
There are several pastes on the market that can be used as an adjunct and
maintenance of bleaching done either external or internal, and have virtually
no effect on the parts not covered.
These pastes contain mild abrasives and are compatible with the enamel (accepted
by the ADA) as silica, pyrophosphate, tripoly pyrophosphate, aluminum oxide,
hydrogen peroxide, baking soda and, lately, lemon essence in those cakes that
contain natural herbs.
Their effectiveness is related to usage time and reducing the consumption of
those foods or beverages that generate pigments or extrinsic stains

Generally, bleaching done in the office it takes
about one hour, and the patient will have already seen significant
changes. This is followed by a
complementary treatment at home, with the respective indications of the
dentist. This treatment can be repeated
at high concentrations in maintenance mode after six months to a year,
depending on the severity of the stains or pigmentation of the patient.
There are two types of whitening: the external and internal.
External Whitening
External whitening takes place in the vital teeth, with the whitening product
being used on the outside of the tooth.
It is generally done in the office and is complemented by a home
treatment that the patient completes with the indications received by the
dentist.
Internal Whitening
Internal whitening is performed on teeth not vital, that is they already have
done a treatment through applying the product inside of the tooth and can
complement this treatment with external bleaching.
Causes of obscurement of teeth
Among the causes of stains and darkening of the teeth
are those that are so-called intrinsic.
These are caused in the formative stage of the tooth before eruptions in
the mouth. Some causes of those spots or
discolorations are:
The tooth whitening treatment is an aesthetic
(cosmetic or aesthetic dentistry) that leaves the teeth several shades whiter,
brighter and healthier and can be done in the office or at home.
The whitening of the teeth also allows for the removal of stains caused by
medications or by extrinsic causes such as tea, coffee, cigarettes, red wine,
other substances and food.
Tooth whitening does not cause abrasion (wear), nor does it weaken teeth. It simply uses gels that can act chemically
to reduce various tones within the same color of the tooth.
The bleaching has no effect on any restorations, these being amalgams,
restorations made with halogen light, inlays and crowns or bridges. For the patient with this type of
arrangement, the bleaching is first done prior to replacement of restorations
that have not changed their color. To make the replacement of these
restorations it is necessary to wait about fifteen days so that the color
obtained with the bleaching stabilizes.
Tooth whitening in the office:
Advantages:
Controlled by professional
Minor side effects
Increased release and penetration of the gel
When done in an office, different gels can be applied on the teeth, as
discussed below, which are based on hydrogen peroxide to 35%. The gels that are recommended for use at
home, after treatment in the clinic, are of lesser concentration.
Steps of external bleaching in the office:
Clean, protection of gum, placement of the gel, applying light, withdrawal of
the gel.