Sunday 23 September 2018

Bleaching teeth


Should you bleach your teeth?
                                                    
If I was a working dentist I would begin by assessing your expectations. If you expect bleaching a few teeth to change their life then I would be wary.  If you turn up with a picture of a famous celebrity I would be wary. If you expect lighter teeth to give you slightly more pride in your teeth then good.

I would then consider timelines. Do you have wedding photos coming up? A deadline may necessitate more rapid bleaching such as in office based light activated bleaching. Regular home based bleaching may take weeks.  
I would then consider present appearance of your teeth. If they are obviously evenly dark then the staining is probably associated with some long forgotten medication or illness. If the staining is uneven it is more likely a dental problem. Either a dead tooth or fillings or crowns.

Age is also important. Teeth become darker with age. The main difference with age is sensitivity. As teeth age shrinkage of the gums can make the teeth more sensitive.

As teeth age they acquire chromogens.  These are large compounds which stain teeth. Hydrogen peroxide changes these compounds lightening teeth. Hydrogen peroxide can be delivered to teeth direct or as carbamide peroxide. 
You need to place hydrogen peroxide in contact with your teeth. The laws relating to amount of peroxide vary from country to country which says nobody knows the right amount and the laws were draw up by politicians. New Zealand legalizes higher amounts than in Aus. The UK has much lower levels. 

There are many ways of placing the bleaching gel on the teeth. Some dentists do this in the chair.  Main advantage is it’s quicker.

Another common way is with a dentist made tray. An impression of your teeth is taken and a specific tray made.  The trays keep the bleaching gel in contact with the teeth longer. You normally wear the trays at night when you are asleep.
Bleaching toothpastes. If used regularly they do what they say. What they don’t say is that the teeth will become more sensitive. This may or may not be an issue for you. They will take much longer to work.  Main advantage is no change to your oral care habits.

Bleaching mouth rinse. Similar to toothpaste. Will not be in contact with the teeth for long period of time.  Therefore it will need a lot of contact times. Need a large number of applications because each application is very short.

Once bleaching has finished the teeth begin to reacquire chromogens. Bleaching teeth doesn’t stop chromogens from returning. There is a constant movement of compounds between teeth to saliva. After bleaching they resume staining.  You can’t combat this by bleaching continually. Over bleaching your teeth will damage them.

Is it safe and what can go wrong?

The most common side effect is increased sensitivity. Teeth can become more sensitive to hot, cold, food, drinks or the air.  Teeth are like chalk. They are a porous living material.  If you change the hard substance the internal nerve reacts differently.

The increased sensitivity is unpredictable. How much of an increase, how long it will last and how people will react is all unknown.

Irritation of the gums or mucous membranes is possible. If it occurs it will resolve immediately you cease bleaching.
Uneven bleaching is possible. Normally occurs initially and with further bleaching it evens up.

Another possibility is after bleaching your fillings, crowns and veneers will appear darker.  The bleach will affect these existing fillings and crowns but it will be so light it can be ignored.

No study has shown an increase in decay.

Should I see a dentist?”

Yes. Anybody can buy bleaching toothpaste or bleaching strips but if you want a lifelong healthy mouth you need a good relationship with a dentist. If you bleach by yourself at home the dentist will know and it will affect their treatment.

A smile is indicator of lots of things. Socio-economic status for one.

But, personally, for me a smile comes from within. You can’t fake it with whiter teeth.  A relaxed, confident and unique smile is more beautiful than a picket fence of perfect teeth.