All you've wanted to know about teeth whitening
19 May 2016
Recent studies show that your mouth is one of the most important elements in others’ perception of you. If you're thinking of having your teeth whitened before your wedding, take a look at this article from Dr Phillip J Townes BDS, lead dentist at Townes and Townes
Having whiter, straighter teeth can instantly improve your self-esteem and dramatically increase your chances of promotion.
And it improves your appearance for that all-important big day. But there are many myths surrounding what tooth whitening consists of, what the effect it has is and which is the most effective method. Here, five common questions concerning teeth whitening are answered by Dr Phillip J Townes.
1) What are the stains on my teeth made of?
Your teeth are made up of several layers, starting with the central pulp, surrounded by dentin and then protected by a hard layer of enamel. Eating, drinking and smoking forms another layer on the outside of the enamel known as a pellicle film. This can be partly cleaned away through brushing, especially with whitening toothpastes and oral hygienists can clean away part of the film through scraping and chemical treatments.
As the pellicle layer sits on the teeth, foreign material can get into the porous surface of the enamel, working its way into the depth of the teeth and staining them. Professional tooth whiteners set off an oxidising reaction within the teeth that breaks the staining compounds down, removing the stain from your teeth.
2) Is home tooth whitening dangerous?
If you aren’t buying your home tooth whitening kit from a reputable source, home tooth whitening can potentially be very dangerous. There are many products available to buy online that are advertised as ‘non-peroxide’ whitening gels but rather than being a safe alternative to peroxide as many might think, these gels contain sodium perborate and are extremely dangerous.
Sodium Perborate is banned without exception in cosmetics within the EU and is classed as carcinogenic and mutagenic - meaning that its use could potentially cause mutations in the children of users. Be aware that any product not bought from a reputable online source may not have been properly tested.
3) Is home tooth whitening as effective as professional tooth whitening?
Legal and safe home tooth whitening is less effective than home tooth whitening; a 2012 EU Council Directive makes it illegal for anyone other than a dental professional to use products containing 0.1% hydrogen peroxide, whereas dental practitioners may use products containing up to 6%. Tooth whitening when carried out on suitable teeth will permanently lighten the colour of your teeth.
4) Can I get my teeth whitened at a beauty salon?
Many beauty salons offer tooth whitening, or ‘unsupervised’ tooth whitening. Both of these, if using a kit that is stronger than 0.1% (the same strength available in home tooth whitening kits), are illegal. Many salons may be using kits many times stronger than that (sometimes up to 23.8% hydrogen peroxide) which can cause gum lesions and other significant oral damage, especially when applied by an untrained amateur.
‘Unsupervised’ tooth whitening is an attempt to avoid the EU regulations on using illegally strong kits -- the patient may be instructed how to use the product and then left alone to carry it out. This is still illegal and can be extremely dangerous.
The only people who should be carrying out tooth whitening with hydrogen peroxide at a strength above 0.1% are dental professionals. Products of this strength should only be sold commercially to dental practitioners and used after the dentist has thoroughly examined their patient and taken a full medical history to ensure there are no risks or concerns about their health during the procedure.
5) Does tooth whitening work on crowns and dentures?
Tooth whitening will not work on crowns and dentures and may require more work for teeth with fillings. If you are considering having your dental professional carry out tooth whitening, be aware that you may need to have alterations made to dentures and crowns; as these were made to match the colour of your original teeth, you may need to have them altered to match your newly-whitened teeth.
If you’re planning on having your teeth whitened, make sure you are fully informed before you decide how to proceed.