Teeth whitening: Everything you need to know
The colour of our teeth is important. While it may seem superficial, for many of us it really does affect our willingness to smile.
If you’re worried about discolouration in your mouth, you may be considering seeking either professional teeth whitening treatment or store-bought products. The question is, will they work? What do they actually do?
In this guide, learn everything you need to know about teeth whitening treatment at the dentist or at home, from how it works to safety and comfort tips backed by science.
In this guide:
What colour are teeth supposed to be?
What goes into a tooth’s colour?
Enamel: The outside layer of your teeth is called the enamel, and this has a natural whitish hue. For some people this hue is more white, and for others it’s more dull.
Dentin: The second layer of your teeth is called the dentin, which is a bony layer just beneath the enamel. Dentin has a yellow hue, or for some people it may be yellow with a tinge of red or even amber.
Enamel thickness: People with a thicker layer of enamel may have teeth which appear more white, because it blocks more of that underlying yellow colour. People with a thinner layer of enamel may have teeth which appear more yellow. Both are perfectly natural!
Habits: What you do with your teeth can affect the colour of the enamel either through staining or factors such as decay. More on that below.
Common causes of yellow or discoloured teeth
Eating and drinking: What you consume can stain your teeth, either temporarily or more permanently. Tea, coffee and wine are quite common causes of stains.
Smoking: Smoking not only contributes to decay, it can also discolour your teeth quite badly as the nicotine gets trapped in the pores of your enamel.
Tartar: Tartar is that yellowy-white stuff that forms, then hardens, on your teeth over time. It can cause stains, and in turn become additionally stained by food and drink. Tartar also contributes to decay, another common cause of discolouration (among more serious issues).
Certain medications: Some medications have been known to change the colour of the dentin, making it darker or deeper in yellow colour.
Age: Teeth can get a lot of wear and tear over the course of our lives, leading to discolouration by the time we grow older. This could be due to a weathering of the enamel, a build-up of stains, or various other factors.
Want to learn more? Check out our Help Centre article on yellow-stained teeth.
What is the colour of tooth decay?
Tooth decay happens in stages, so you will usually see its colour change over time unless you intervene by visiting the dentist.
Tartar build-up may appear as yellow or brown on, between or behind your teeth. Depending on your habits, it may also form as a different colour – it’s quite porous, and stains easily from food and drink.
White spots could be a sign of demineralisation, that is, the hard minerals which make up your enamel wearing away.
Brown spots could come next if the white spots aren’t treated, as the enamel decays further. This decay can also cause dental cavities.
If brown-coloured decay continues to go untreated, it can cause a variety of other more serious problems which may be invisible (but will likely cause other symptoms, such as tooth sensitivity, swelling, bleeding, abscesses, fevers and so forth).
Understanding teeth whitening: What is it?
Dry socket can happen to anyone. However, these risk factors may increase the chance that it occurs:
Improper tooth extraction care at home: The guidelines you’ll receive for managing tooth extraction pain and dry socket are vital for ensuring the healthy formation of the blood clot.
Smoking: Cigarettes and other tobacco products can inhibit healing at the wound site. Additionally, the act of sucking may dislodge a newly formed blood clot.
Poor oral hygiene: Gum disease, infection and other complications from poor oral hygiene may increase the risk of dry socket.
Birth control: Oral contraceptives such as birth control have been known to contribute to disrupting the regular healing process.
History of dry socket: Those who have had dry socket after a tooth extraction before may be at a higher risk of developing it again.
How does teeth whitening work?
There are a few different methods for whitening teeth, ranging from over-the-counter box sets to professional-grade techniques which can only be performed by dentists.
Some of the common techniques include:
Hydrogen peroxide: A chemical which reacts with darker molecules in your teeth, making them smaller and appear less strongly. This is one of the most common teeth whitening methods.
Carbamide peroxide: Another common teeth whitening chemical, considered slower than hydrogen peroxide but less harsh (i.e. it typically causes fewer side effects).
Abrasives: Substances designed to be harder than stains but less hard than tooth enamel, allowing the user to scrub away stains.
Light-based kits: Which are commonly made with hydrogen peroxide gel, activated by a special light to speed up the whitening process.
There are quite a few more beyond this small list, but as the NZ Dental Association notes, hydrogen peroxide kits tend to be the most typical found in this country.
Why would someone whiten their teeth?
The shape, alignment and colour of our teeth can greatly impact our self confidence. Time and again, studies like this one, this one and this one have shown that people’s thoughts on their own smile (in both adults and children) are impacted by the colour of that smile.
Teeth whitening treatment is, therefore, often seen as a chance to either fit in better with a group, jazz up our look, feel more healthy or improve our self-esteem.
Is teeth whitening bad for your teeth?
Generally speaking, teeth whitening kits are considered safe to use - particularly those relying on hydrogen peroxide as the key whitening method. While they may cause side effects such as temporary tooth sensitivity or gum irritation, they shouldn’t cause long-lasting damage to your teeth.
That said, not all teeth whitening methods are equal, nor are all teeth.
It is important that you always get a check-up with your dentist before starting any teeth whitening treatment, in case you have an underlying condition that may be affected by the chemicals or abrasives.
For example, if some whitening agent got through cracks or cavities in your teeth, it could cause damage to your tooth pulp (the innermost layer, under the dentin), and even weaken your fillings.
Additionally, some teeth whitening treatments aren’t backed by science and may pose a risk to your health. More on that below.
Can people with sensitive teeth get teeth whitening treatment?
If you have sensitive teeth, it is still possible to get teeth whitening treatment. That said, it’s all the more important that you seek professional dental advice before making any purchases as some teeth whitening kits may cause a lot of discomfort.
It’s possible your dentist may recommend kits with a lower concentration of bleaching agent, or that you brush your teeth with desensitising toothpaste before applying any whitening agents.
By popping in to see your dentist, they can examine your mouth, talk about your needs and recommend a course of action.
Is teeth whitening covered by health insurance?
Cosmetic treatments such as teeth whitening are often excluded from health insurance policies, so it’s vital that you check with your insurer before making any big decisions if this is important to you.
Common professional teeth whitening techniques
At-home teeth whitening kit
At a teeth whitening consultation, your dentist may recommend that you take home a teeth whitening kit moulded to your specific mouth. You would then apply the treatment around your regular schedule.
How does it work?
Your mouth will be checked and possibly x-rayed to make sure your teeth are safe to whiten. Then, a mould will be taken of your upper and lower teeth so that a plastic tray can be made which fits snugly to your exact mouth.
Additionally, your dentist will give you a special whitening gel which goes along with the kit. If you have sensitive teeth, this gel may include some desensitising agents to help.
Over the course of about two weeks, you’ll use the tray to apply gel to your teeth and should see a difference within a day or two (although it’ll take the full two weeks to get to your desired new shade).
Learn more: Teeth whitening at Kowhai Dental Whangārei
LED or laser teeth whitening
In-surgery light-based whitening treatment using special bright LEDs or lasers is designed to offer accelerated results compared to an at-home kit. Although, you can also find light-based kits at many pharmacies.
How does it work?
First, the dentist applies a teeth whitening gel to your teeth as normal – then points a special light or laser at your open mouth for the duration of the treatment. The idea is that the light helps break apart the gel faster, providing results more quickly than a take-home teeth whitening tray.
The science is mixed on the efficacy of this treatment. Some research (like this paper) has shown, for example, that blue light may not accelerate the bleaching process as much as advertised. Other research (like this paper) also suggests it may cause more side effects than slower at-home treatment options.
That said, there are also papers suggesting the opposite.
Not sure what’s right for you? The best advice is generally to always to talk to your dentist.
Scaling and polishing
Scaling and polishing are common dental hygiene treatments designed to give your mouth a thorough clean using specialised tools, helping to treat or prevent tooth decay.
What is scaling and polishing?
Scaling and polishing is a multi-stage process which removes plaque and tartar build-up, polishes your teeth, and gives your dental hygienist a chance to look for any signs of decay.
Does scaling and polishing whiten teeth?
Officially, no. The treatment is not designed to whiten teeth, only to provide good dental hygiene care.
That said, brighter teeth can be a byproduct of scaling and polishing. If tartar was discolouring your mouth and your dental hygienist removes that tartar, your teeth could appear brighter as a result. Additionally, if you have stains on the surfaces of your teeth, the polishing process may remove or lighten them.
So, it isn’t designed to whiten your teeth but it might anyway – that depends on your mouth.
How much does professional teeth whitening treatment cost?
The cost varies depending on which dentist you choose and whether you’re getting a take-home kit or in-chair lightening. The cause of your teeth discolouration and the severity can also affect the price.
We’ve seen costs around New Zealand range most commonly around $500-700+ for in-chair lightening treatments. Take-home kits are usually less expensive.
At Kowhai Dental, we charge at the lower end for professionally moulded take-home teeth whitening kits, at $300 (including a 30-minute consultation).
But remember, you need to see a dentist first before starting any treatment. While this can add cost, it could save you from further complications in the long run if your teeth aren’t ready to be whitened yet.
Common side effects of professional teeth whitening
Teeth sensitivity, which may last up to a couple of days.
Temporary aching in the teeth caused by an improperly fitted whitening tray.
Brief moments of tingling in your teeth.
Gum irritation, and possibly inflammation.
Damage to the enamel or even pulp may also occur in some cases, depending on your chosen teeth whitening method, how it was performed, how often it was performed, and the state of your teeth to begin with.
How long will my teeth remain sensitive after teeth whitening?
If you experience sensitivity after whitening your teeth, it will likely peak during or immediately after treatment and last for up to a couple of days.
What can I eat and drink after teeth whitening treatment?
You can usually go back to normal after teeth whitening treatment, unless you’re experiencing added sensitivity. If this is the case, you may want to consider avoiding:
Very hot or very cold food.
Acidic, sour or very sweet food.
Vigorous brushing may also be uncomfortable during this time, in which case it’s recommended that you brush a bit more gently or opt for a soft-bristled brush for a couple of days. You could also consider using a toothpaste designed for sensitive teeth.
Common home/natural teeth whitening techniques (facts and fiction)
How do you whiten teeth naturally at home?
There are many different ways to lighten your teeth naturally at home, though one of the best, safest methods is simply to maintain good dental hygiene.
That said, you’ll see a lot of options advertised online either in the form of over-the-counter products or naturally occurring substances. The science is dubious on quite a few of these, and some may even be harmful.
We’ve compiled a list of some of the most common so you can make an educated decision for yourself. Uncertain? The best place to look for advice is always your dentist.
1. Good dental hygiene habits
Regular brushing of your teeth and gums with fluoride-containing toothpaste will help keep plaque and tartar at bay, helping limit their impact on the colour of your teeth (not to mention the damage).
On top of that, brushing regularly will keep your teeth nice and clean more generally, removing recent stains before they have a chance to set in or build up.
Good flossing can also help keep bacteria at bay.
Learn more: How to clean your gums and keep them healthy
2. Oil pulling
Oil pulling is a long-held practice of swishing certain oils around your mouth to improve your health. The idea is you’d put a teaspoon of coconut, sunflower, sesame or olive oil in your mouth and swish for 15-20 minutes, repeated daily for a couple of weeks.
The idea behind the practice is that it ‘pulls’ the bacteria off your teeth and gums, helping improve oral health generally and whiten your teeth more specifically.
Some people swear by it, and it’s been in practice for generations in some countries. That said, there’s no scientific support for the idea that it can whiten your teeth (for example, this report).
3. Baking soda
Baking soda is a common ingredient in toothpastes, but some users skip the toothpaste part and apply a straight mixture of baking soda (1 tsp) and water (2 tsp) to use as a teeth whitening paste.
Due to its mild alkaline nature, baking soda can generally be used in the mouth without side effects. Like most natural or household medical products, there’s a lot of scientific debate about its efficacy, however studies such as this one, this one and this one suggest that it may have some long-term teeth whitening benefits.
Although, using toothpaste containing baking soda may be more effective than baking soda on its own.
4. Strawberries – do they whiten teeth?
Strawberries mixed with baking soda is a common natural health remedy for whitening teeth, with the idea that the particular type of acid in strawberries combined with the scrubbing effect of baking soda can remove discoloration.
If this mixture has any effect at all, science (like this report) says it’s minimal – especially compared to alternative products. Additionally, overuse (discussed in this report) could be actively harmful, eroding away your enamel.
5. Over-the-counter whitening products
Teeth whitening strips
If the teeth whitening strips you’re looking at contain hydrogen peroxide or carbamide peroxide gel, chances are they will have at least some effect on the colour of your teeth.
The chemical to watch for is chlorine dioxide. There are far fewer safety studies out there which support the safety of this product, even though some reports suggest it works faster and more effectively than hydrogen or carbamide peroxide gels. Reports exist (like this one) of it stripping the enamel from teeth, potentially leaving them more sensitive, rougher to the touch and more likely to stain.
Activated charcoal toothpaste
Activated charcoal grew to become a big trend in the 2010s, with some proponents saying that, among its many touted benefits, it can also whiten your teeth when used in a toothpaste.
This is one we’d advise caution on. While some studies have shown it may be able to whiten your teeth (like this one), its abrasivity means it can also harm your teeth at the same time. That example we just linked suggested it was less effective and less safe than regular teeth-whitening toothpaste. This review comes to similar conclusions.
Whitening pens
Teeth whitening pens (also called brush-on whiteners) generally aren’t that different to teeth whitening strips. They are essentially gel-based products (hydrogen peroxide being common) that are applied to the teeth directly via a provided brush.
You’d likely find the results similarly effective to teeth whitening strips, being that they do the same thing. The application is the key difference.
Should I bother getting professional teeth whitening if over-the-counter products do the same thing?
From a results standpoint, it may appear that over-the-counter products are going to do the same thing (at a cheaper cost) than visiting a dentist.
However, we’d advise caution and recommend scrutiny. Remember, not all teeth are ready to be whitened. If you have an underlying problem, or you unintentionally misuse a natural or store-bought product, you could do your mouth more harm than good.
The best thing you can do for your teeth when choosing a whitening product is visit your dentist first. They can either provide professional treatment, or advise on what might be best for you individually with regards to store-bought alternatives.
Need an appointment? Give us a call
Our professionally trained dentists and dental hygienists are ready to help. We’ll take the time to understand your mouth, and recommend the best course of action for your needs.
To book an appointment, pop in to see us on Maunu Road, give us a call at 09 430 0707, or book online.