Dental bleaching, also known as tooth whitening, is a common procedure in general dentistry and in the field of cosmetic dentistry. As a persongrows older the adult teeth often become darker because the enamel becomes less porous and mineral structure of the tooth is disturbed. Teeth can also become stained by bacterial pigments, various foods or drinks and tobacco. Also some medicine, for example tetracycline, can alsocontribute to teeth stains.

Dental bleaching can be performed as at-home or in-office procedure. One of the most common methods of tooth whitening is gel bleaching which can be performed either with high-concentration gel or low-concentration gel.

High-concentration bleaching can be performed in the dental office as well as at home. In-office bleaching procedures use a protective layer that is carefully painted on the gums to reduce the risk of chemical burns to the soft tissues. The bleaching agent is either carbamide peroxide orhydrogen peroxide. The bleaching gel typically contains between 10-30% carbamide peroxide (15% is recommended) which is roughly equivalent to 3-10% hydrogen peroxide concentration.

Low-concentration whitening is less effective, and is generally only performed at home. Low-concentration whitening involves purchasing a thinstrip that contains a low concentration of oxidizing agent that should be kept next to the teeth for several hours a day for a period of 5 to 14 days.

Internal staining of dentine can discolor the teeth from inside out. In such cases, internal bleaching can be an answer. If patients teeth are discolored due to heavy stains or tetracycline, and whitening seems not to be working, power bleaching is recommended. Power or light-accelerated bleaching, sometimes referred to as laser bleaching, uses light energy to bleach teeth at the dentist’s office. Nowadays various types of energy can be used in this procedure i.e. halogen, LED, or plasma arc. A power bleaching treatment typically involves isolation of soft tissue with a liquid barrier, application of a professional dental-grade hydrogen peroxide whitening gel (25-38% hydrogen peroxide), and exposure to the light source for 6-15 minutes. Most teeth whitening treatments can be done in approximately 30 minutes to one hour, in a single visit to a dental physician.

Side effects of teeth bleaching include: chemical burns with gel bleaching, sensitive teeth, and overbleaching (known in the profession as "over white teeth" or "Hyperodonto-oxidation").

Bleaching is not recommended in children under the age of 16. Tooth whitening is also not recommended in pregnant or breast-feeding women.

GLOSSARY
accelerated – przyspieszony
to grow older – starzeć się
agent – środek, czynnik 
gums – dziąsła 
approximately – przeciętnie, średnio 
high-concentration – wysokie stężenie 
barier – bariera 
internal – wewnętrzny
breast-feeding – karmiące piersią 
to involve – pociągać za sobą
burn – oparzenie, poparzenie 
less effective – mniej skuteczne
case – przypadek 
protective layer – warstwa ochronna
common – powszechny, ogólnie dostępny 
porous – porowaty 
to contain – zawierać to 
reduce the risk – zmniejszać ryzyko
to contribute – przyczyniać się 
sensitive – wrażliwy 
dental bleaching – wybielanie 
soft tissue – tkanka miękka 
dentine – zębina 
stain – plama, plamić 
enamel – szkliwo 
strip – pasek 
exposure – wystawienie na działanie 
from inside out – od środka na zewnątrz
 

1. Tooth whitening has little or no _ f _ _ _ _ on tooth’s nerve. 
2. Dental bleaching has usually no side effects, but sometimes chemical b_ _ _ s may occur. 
3. Various drinks, foods and smoking cigarettes can _ _ _ i _ teeth. 
4. ‘Keep this _ _ _ _ p with oxidizing agent on your teeth for 15 minutes’. 
5. ‘Now, I’ll apply this liquid as a b_ _ _ _ _ _ to protect your gums from burning’. 
6. Tooth whitening products sold in the sops _ _ _ t _ _ _ low-concentrations of hydrogen peroxide. 
7. ‘In your _ _ _ e we must use stronger teeth whitening preparation’.
8. One of the possible adverse effects of dental bleaching is that your teeth may become more _ _ _ _ _ _ _ v _.

EXTERNAL 
LOW CONCENTRATION 
INEFFICIENT 
DELAYED 
HARMFUL 
IMPENETRABLE 
ABOVE/OLDER THAN

1. ‘Teeth whitening is not permanent. People who expose their teeth to foods and beverages that cause staining may see the brilliance start to fade in as little as one month’.

2. ‘Because children and adolescents may experience an increased sensitivity and are more likely to have problems, we do not recommend tooth whitening for children’.

3. ‘You can help to keep your teeth white by cutting down on the amount of food and drink you have that can stain teeth. Don’t forget, stopping smoking can also help prevent discoloring and staining’.

4. ‘Teeth whitening products using 10% carbamide peroxide have little effect on the hardness or mineral content of a tooth's enamel surface’.

5. ‘The issue here is not "damage" to existing restorations; rather, keep in mind that existing restorations such as tooth-colored fillings, crowns, bonding, veneers, and bridges do not lighten’.

1. Proszę używać tego produktu raz dziennie zarówno na górną, jak i dolną szczękę.
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2. Teraz proszę się nie ruszać. Muszę nałożyć ten preparat bardzo precyzyjnie, aby uniknąć podrażnień na dziąsłach.
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3. Niestety nie może Pani stosować preparatów wybielających u Pani córki. 
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4. Jeśli będzie Pan unikać picia kawy i rzuci Pan palenie, efekty wybielania będą dłużej widoczne. 
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5. Po użyciu preparatów wybielających Pani zęby mogą być bardziej wrażliwe na zimne i ciepłe pokarmy.
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Lesson 1 answers