Will teeth whitening damage my teeth in the long run?

Yellow vs White Teeth Photo

Will teeth whitening damage my teeth in the long run?

Our teeth can become discoloured or stained drinking tea or coffee over time. Yellowing of the teeth can happen with age as well, which is quite a bummer. Everyone wants their pearly whites to be, well, white and shiny – the reason why some opt for teeth whitening procedures at their dentist. But you may wonder, what exactly does it entail? Are the long-term benefits going to outweigh their disadvantages? We’re here to guide you through some of the must-knows about teeth whitening, and whether they do more good than bad for your teeth.

What is teeth whitening?

Teeth whitening is a process that lightens the colour of teeth. It can be done by physical removal of the stains, or through chemical reactions. Bleaching is a chemical process using hydrogen peroxide or carbamide peroxide that degrades the chromogens. Chromogens are compounds that have darker shades than teeth that collect in or on the teeth, thereby staining them. 

Read more about some fun facts of teeth whitening!

What are the methods of teeth whitening in Singapore? 

Tooth whitening in Singapore can be performed either by dentists “in-office” or at home using “over-the-counter” (OTC) products. 

In-office teeth whitening 

In-office teeth whitening can deliver results faster than other methods because they use greater concentrations of peroxide than OTC – about 35 wt% . The gums will need to be coated with a protective gel because concentrated hydrogen peroxide is highly oxidising, thereby having the potential to damage soft tissues like gums. Then, the hydrogen peroxide bleach is applied to the teeth for about 20 – 30 min. 

Some products are said to increase the oxidation of chromogens through heat or intense blue light of wavelength 480 – 520 nm to achieve teeth whitening. Some dentists may also use lasers (light activation) in order to speed up the chemical reactions. This is an “off-label” use in dentistry, according to the US Food and Drug Administration (FDA). Such whitening systems are not shown to provide added benefits even though they are in use and are hence not endorsed. 

Many patients show show results within 1 session of about 30 – 60 minutes of in-office teeth whitening, but you may opt for several rounds of bleaching for more dramatic results. 

Whitening Toothpaste

Whitening toothpaste 

Whitening toothpastes have more abrasives and detergents than normal toothpaste, enabling them to remove more stubborn stains. They do not contain bleach like sodium hypochlorite but some of them can contain small amounts of carbamide peroxide or hydrogen peroxide which help to make teeth slightly whiter. They can lighten teeth colour by about 1 or 2 shades.

OTC Whitening strips and gels 

OTC whitening strips are plastic strips that contain a thin layer of peroxide gel that are applied onto the surface of the teeth. There is a wide range of whitening strip products sold in the market. Typically, the strips are applied once or twice each day for 30 minutes for about 2 weeks or so. The colour of the teeth will lighten by about 1 or 2 shades in several days.

Meanwhile, whitening gels are peroxide-based gels applied with a small brush onto the surface of teeth. Similarly, they are applied twice a day for 14 days, with the effect of teeth lightening by about 1 or 2 shades. 

As a word of caution, please use teeth whitening strips and gels in moderation as overuse can lead to tooth sensitivity and even damage your enamel over time! 

Whitening rinses 

Whitening rinses contain hydrogen peroxide and should be used to rinse teeth twice a day for 60 seconds. This takes a longer time period of about 3 months to see teeth lightening of about 1 or 2 shades.

Tray-based tooth whiteners 

Tray-based tooth whiteners are available both at the dental clinic and OTC. They use a fitted tray of carbamide peroxide bleaching gel and are worn on the teeth for 2 – 4 hours a day or overnight. The teeth whitening effect of about 1 or 2 shades is achieved within a few days.

Is it bad to whiten your teeth? 

There are some risks associated with teeth whitening procedures, especially if the concentration of bleaching agent used is higher. The degree of the side effects depends on the concentration of the peroxide bleaching agent, the duration of the treatment, and the non-bleach composition of the product. 

Some common side effects of teeth whitening include: 

  • Increased tooth sensitivity – usually happens at time of treatment and can continue for several days, especially when eating or drinking hot or cold foods
  • Mild gum irritation – usually happens within the day of treatment and can continue for several days 

Additional risks reported from in vitro studies include: 

  • Tooth erosion – loss of surface of the teeth 
  • Tooth mineral degradation – loss of tooth enamel
  • Increased susceptibility to demineralisation 
  • Pupal damage – damage to the connective tissue in the teeth 

Some aggressive methods may cause dehydration and demineralisation of the tooth so that it temporarily appears whiter. Plus, peroxides are antibacterial and can cause an imbalance in the normal microflora of the mouth. 

Generally, when used appropriately according to given instructions, home-based bleaching using OTC products can result in less sensitivity than in-office bleaching. However, this usually isn’t the case due to a lack of patient compliance or patient education on potentially damaging ingredients on OTC teeth whitening products. 

Hence, we suggest getting teeth whitening under the care of a responsible dentist who can plan and advise you on an appropriate treatment plan.

Is it worth getting your teeth whitened at the dentist? 

We know that the side effects can sound scary and off-putting, but be sure to weigh the pros and cons before you make a decision. As mentioned, in-office teeth whitening has supervision from professionals, so the side effects are likely to be minimised if you go to someone with experience and expertise. Besides, with the benefits that teeth whitening can bring, it’s really something worth considering and investing in. 

Improved aesthetics can boost confidence 

Professional teeth whitening treatment removes stains and brightens your teeth, leaving you with a stunning, younger-looking smile. This can boost your confidence and self-esteem, because when you look good, you feel good as well. 

Better oral health 

Besides, all this cleaning can only mean one thing – better oral health. Brighter teeth are cleaner, and with regular brushing and flossing, you can ensure you have healthier and stronger teeth. 

Personalised treatment 

If you go for in-office treatment, the doctor will likely be able to advise you on what’s best to get brighter looking teeth. You may even get custom-made trays that can apply the whitening agent uniformly, unlike OTC products which may cause uneven whitening if not done properly. You can even decide on the shade of white you want to achieve, something you can’t control with OTC products. 

Expertise and informed decisions

Dentists don’t just apply whitening products blindly. They will obtain your history, do examinations to figure out what type of stains you have, and figure out the best approach to get the best outcome. Intrinsic stains and extrinsic stains are different – the former comes from within the teeth while the latter are a result of lifestyle choices like the food you consume. Either way, it is always best to hear from your dentist so you can make informed decisions to achieve your desired goals.


While there may be some side effects of teeth whitening, especially with higher concentrations of bleaching agents, there are also benefits that could outweigh the disadvantages. Ultimately, it boils down to what you really want, so consulting the dentist before you make a decision would be the best step forward. 

If you decide to do in-office whitening treatments, do ask your dentist how to manage the risks for teeth sensitivity. 

Remember to maintain good oral hygiene and go for checkups at the dentist regularly to keep your smile looking good and sparkly!


  1. Carey C. M. (2014). Tooth whitening: what we now know. The journal of evidence-based dental practice, 14 Suppl, 70–76. https://doi.org/10.1016/j.jebdp.2014.02.006 
  2. Epple, M., Meyer, F., & Enax, J. (2019). A Critical Review of Modern Concepts for Teeth Whitening. Dentistry journal, 7(3), 79. https://doi.org/10.3390/dj7030079 

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