Teeth whitening is a process of changing the colour of your teeth through the use of an active agent called peroxide. Peroxide causes a process of oxidation which releases oxygen into your teeth, cause the compounds to reorganize and produce a visibily whiter colour

Why is it done?

When we eat and drink darker colours such as coffee and curries, the colour gets absorbed into our enamel. This can cause teeth to look yellow and ‘dirty’.

Teeth whitening is a purely cosmetic procedure that aims to brighten and improve the colour of teeth to make a smile look clean, healthy and younger.

Is it harmful?

Short term use of certified FDA or HSA approved, teeth whitening gels are effective and safe. There are no long-term studies to show that teeth whitening gels with peroxide can cause teeth to become weaker, or have any negative impact on gums.


Temporary side effects include heightened sensitivity and gum irritation. It is normal to feel some sensitivity during the process due to the nature of the reaction happening within the teeth to cause the colour change. Rest assured that for most cases, the teeth sensitivity or any mild gum discomfort should go away within 24 – 48 hours of removing the gel. Gums can get irritated when strong concentrations of peroxide are used, causing the gums to feel sore or even ulcerate. It is important not to overload the whitening trays and wipe off any excess gel around the gum line during teeth whitening process.

How fast can I whiten my teeth?

If you have a big occasion coming up such as a wedding, its best to plan for this!

How fast your teeth whiten depends on which mode of teeth whitening you choose. The same results can be achieved with lower concentrations of peroxide over longer exposure time and vice versa.

Chairside teeth whitening is a procedure done in the dental office, where a stronger peroxide base e.g. 15- 40% of hydrogen peroxide is applied to the teeth for 1 hour, sometimes with or without a light activated add on depending on the manufacturer. This can produce teeth 4- 6 shade white according to Philips ZOOM whitening. However, if teeth have been whitened before or the base shade is already quite white, then it may not have such a big difference.

Take home kits are a procedure done at home, where a milder peroxide based whitening gel (hydrogen peroxide 4 – 8 % or carbamide peroxide 10 – 22%) can be used over a period of up to 2 weeks. Depending on the manufacture’s guidelines and the concentration of the gel, you could be wearing the gel for 20 minutes per day or overnight, for up to 2 weeks before you see visible results. However, this is the most popular mode of whitening due to the convenience and milder side effects of sensitivity and gum irritation.

Usually we recommended to do chairside whitening ($800 – 950) to kickstart the process, then do the take home whitening kit ($350 – 500) for maintenance every 3- 6 month after.

Can I eat and drink normally while whitening my teeth?

When peroxide is in contact with your teeth, the oxidation and colour change is pending. That means that while it is not an absolute no no, it is best to avoid dark coloured foods and drinks such as coffees, teas, red wines or curries. Smoking should also be minimized. If absolutely necessary to ingest, then be sure not to prolong the duration of consumption. For example, have your coffee with a straw, within a 30-minute window rather than sip it throughout the day. Once you’re done with consuming, have lots of water to wash down the colour change so that your saliva is not brown, because that too can cause the whitening process to be slightly jeopardized.

Does it help to use whitening toothpaste?

Whitening toothpastes are a hit and miss. Many of them claim to be whitening because there are ingredients that are highly abrasive, so that stains can be scrubbed off. However, prolonged use of abrasive toothpastes can lead to thinning of the enamel and outer layer of the teeth. When this happens, the inner yellower layer of dentine is exposed. So, be wise and careful not to be counterproductive with over the counter products! 

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