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How Does An LED Light Make Your Teeth Whiter?

How Does LED Whiten Teeth

Yellowing teeth are an unfortunate fact of aging, sped up by a number of different lifestyle factors such as smoking and drinking. Many people are now turning to teeth whitening methods to restore their pearly whites. Historically, people headed to their dentist for teeth whitening, and although they can give you great results, it can also be very expensive.

LED teeth whitening kits are becoming increasingly popular, with many celebrities joining campaigns for at-home teeth whitening. But how does it work? And is it safe? We are going to answer all of your questions about LED teeth whitening so that you can decide if it is right for you.

In general, the teeth whitening process works by treating the teeth with an agent which may or may not be bleach-based. Then, to speed up the reaction, a blue light source is shone on the treated teeth. In the past, Ultra Violet (UV) light has widely been used as the light source. However, there are now concerns over the risks of using UV light. UV light is a form of ionizing radiation which can cause the mutation of cells. This is of particular concern in the mouth because the oral tissues are very sensitive, as shown in this study.

LED can be used in place of the UV light as a safer alternative to whiten your teeth. Blue LED light can also be used to speed up the whitening reaction but without the risks of UV light.

What Is LED Light?

What Is LED Light

LED stands for Light Emitting Diode. It is a device which releases visible light when supplied with an electrical current. Often, the light is a single color which can be anywhere between red and blue-violet on the visible light scale. LED lights can be very intense and often brighter than their halogen or incandescent lamp counterparts. They are also a lot cooler as they have very efficient heat-dissipating designs.

LED lights do not need much power but are highly efficient and last a long time, particularly in comparison to other light sources. They do not have a warm-up time, so they switch on at their highest intensity straight away. They are a form of visible light, so they are not a type of ionizing radiation, which means they cannot cause cell mutations. It is a safer alternative to UV light for use in teeth whitening procedures.

How Does LED Light Make Teeth Whiter?

Does It Make Teeth Whiter

LED light works alongside a tooth-whitening agent. The light will not change the color of your teeth if used alone. However, it does act as a catalyst to speed up the reactions in the whitening process when combined with a whitening agent. Commonly-used whitening agents are hydrogen peroxide or carbamide peroxide. Carbamide peroxide, for example, is a slow-acting bleach that when applied to teeth will react, breaking down into hydrogen peroxide and urea. Urea is a waste product, but the hydrogen peroxide removes superficial stains and deeper discoloration by altering their chemical structure.

LED Light Speeds Up Teeth Whitening

A study published in the Open Dentistry Journal found that light speeds up the whitening process, and is backed up by many other studies. This is found in particular when LED activator light is used in conjunction with carbamide peroxide-based whitening agent gels. Where in the past, UV light had been used as a catalyst to speed up the time taken for teeth whitening to occur, LED light is now much safer, and more accessible.

Is LED Tooth Whitening Safe?

LED whitening has been developed to be safe for home use. The use of an LED light source as opposed to older, UV light sources, is much safer. However, bear in mind that while the light is safe, teeth whitening often involves putting bleach into your mouth, so it is important to follow the instructions which are specific to each different kit.

Teeth whitening usually involves applying the bleaching agent either directly to your teeth or to a tray  – like a sports mouthguard  – which you hold in place for the duration of the treatment. There are different types of tray – some give a universal fit, while others you warm up and shape specifically for your teeth. The LED light will usually fix to the tray.

What Are the Risks of LED Teeth Whitening?

At-home teeth whitening can be done very safely with minimal complications. Kits have been developed to make the administration as easy as possible. However, as mentioned before, teeth whitening can involve putting bleach into your mouth, so it is important that you take care. Oral tissues are sensitive, so you must try not to get any of the whitening agent on your gums as this could cause sensitivity and irritation. Swallowing the agent could also result in a temporary sore throat.

Teeth Whitening LED Light Side Effects

  • Sensitivity – You may find that your teeth temporarily become more sensitive after LED teeth whitening. This is usually not permanent, and you can look after your teeth by using toothpaste for sensitive teeth, and also by being very gentle with your toothbrush. You may want to buy a softer toothbrush for while your gums recover.
  • Gum Irritation – If the whitening agent comes into contact with the delicate tissues of the mouth, such as the tongue or gums, the tissues may become irritated. Cell turnover in the mouth is quick, so the irritation will not usually last long.
  • Damage From Overuse – Repeated tooth whitening in quick succession, using too much whitening agent or leaving the agent on for too long can all cause permanent damage to the teeth. This can be prevented by understanding the instructions of the kit and following them carefully.

Benefits Of LED Teeth Whitening

Benefits Of LED Teeth Whitening


Many at-home LED teeth whitening kits can be bought for under $100, making it much more affordable than in-office teeth whitening at your dentist. While it may not last as long, at-home kits can still give great results.


There are plenty of at-home teeth whitening kits that you buy to use at home in your own time. This means you can use it as a touch up for a last-minute arrangement, without waiting for an appointment time.


At-home teeth whitening kits can be extremely successful when used correctly. They are easy to use and come with comprehensive instructions to help you. You can often see results straight away, and they should last a while.

No UV Radiation

The use of blue LED light as a catalyst instead of UV light, which has been previously used, is much safer. Unlike UV light, LED cannot cause mutations as it does not affect tissue on a cellular level.

Negatives Of LED Teeth Whitening

Negatives Of LED Teeth Whitening

No Whitening Method Is Permanent

Due to the nature of tooth yellowing, no whitening method is ever going to be permanent. Different peoples’ teeth will yellow at different rates, but this will be sped up by lifestyle factors and genetic disposition. The natural thinning of enamel and pigmentation of the internal dentin that no matter what whitening method you choose, your teeth will continue to turn yellow. This may take weeks, months or years.

Should Not Be Used During Pregnancy

If you are pregnant, trying to get pregnant or nursing a baby, it is best to delay your teeth whitening. There has been little research into teeth whitening during pregnancy to assess its safety. Therefore, the best option is to wait until you have had your baby and finished breastfeeding.

Results Based On Causes Of Yellowing

The severity of the yellowing of your teeth will affect the possible result. Very yellow teeth may require more treatments; however, it is important not to over-treat teeth. Try to consider the natural color of your teeth objectively and be realistic about the color your aim to achieve.

Can Be Over Done

No tooth whitening method should be done too often or for longer than the instructions say. This is because if left on or repeated too soon the acid in the whitening agent can damage the tooth enamel which can lead to sensitivity and other future problems. Prevent damage by closely following the instructions.

Not Suitable For Everyone

Teeth whitening kits should not be used on children’s teeth. You should instead consult your dentist if you are worried about the color of your child’s teeth. Teeth whitening will not work on dentures or restorative dentistry, for example, crowns, veneers and bridges. These materials will not whiten and so using whitening products on teeth around these materials will cause uneven color throughout the mouth.

How Often Can I Whiten My Teeth?

How Often tO Whiten Teeth

There are three main warning signs when it comes to repeated tooth whitening. If any of them apply, then it is too soon for you to whiten your teeth again:

  • Tooth sensitivity
  • Poor gum condition, such as swelling or bleeding
  • Tooth transparency/appearing blue.

It is important to not over treat your teeth as it can cause long term damage. Some methods of teeth whitening are designed to be used more often, but some dubious methods should not be used at all.

How Often Can I Whiten My Teeth At Home?

Pre-packaged teeth whitening kits have different concentrations of the active ingredients compared to professional teeth whitening that you can get at the dentist. The concentrations of hydrogen or carbamide peroxide are usually lower than what dentists use because they have been specially formulated to be safe for use by people who are untrained and unqualified. They therefore usually require more treatments.

Some at-home kits require as many as 30 treatments, but other than these, as a general rule, it is recommended you do not use at-home kits for more than two weeks consecutively. Also, once you have completed your treatment plan you should not use teeth whitening again for at least 6 months. Similarly, make sure you do not exceed the application times given in the instructions.

At Home Kits From Your Dentist

If you have purchased an at-home whitening kit from your dentist, you should use it only as advised. These are usually stronger than the kits that you can buy over the counter, and you should follow the instructions carefully in order to prevent damage to your teeth and the rest of your mouth.

Example Products

Example LED Teeth Whitening Products

To give you a guide, we have compiled a selection of tooth whitening methods so you can see how often to use them safely. For full guidelines however, please refer to the manufacturers directly for the most up to date and specific instructions.

How Often Should You Bleach Your Teeth With Opalescence?

Opalescence is a make of at-home teeth whitening products which are dispensed by licensed dental professionals. They sell several different strengths of teeth whitening products, ranging from 10% to 45%. Depending on which one you go for, you could be using it for 15 minutes per session for a few days, or leaving it on overnight.

How Often Should You Whiten Your Teeth With Crest 3D Whitestrips?

The Crest 3D Whitestrips can be used back to back on consecutive days for up to 20 days, but only wear each strip for the time limit directed in the instructions. A slightly different variant, the Crest 3D Monthly Whitening Boost Whitestrips are designed to be used for 1 hour, once a month.

How Often Should I Whiten My Teeth With Activated Charcoal?

Many journal articles including this study have concluded that charcoal is an unproven method of teeth whitening. It is also naturally abrasive like baking soda, and some dentists have reported findings that it actually gets trapped into the pores of the teeth, which would have a darkening effect on the teeth – the opposite to what you are looking for! It is better to stick to proven, and medically tested methods of teeth whitening, like at-home kits.

How Often Should I Whiten My Teeth With Baking Soda And Lemon?

It is not advisable to use this method to whiten teeth at all. Baking soda is naturally abrasive and lemon juice is highly acidic and can demineralise your tooth structure. It also does not involve using fluoride, which is a substance that helps to strengthen teeth and prevents cavities from forming, and which is present in toothpastes and often even in tap water.

Using this baking soda method can severely damage the enamel on your teeth which can cause yellowing, sensitivity and decay as time goes on. It can also weaken dental glue, so should not be used if you have braces. Similarly, baking soda should not be used with peroxide for the same reasons.

How Much Does LED Teeth Whitening Cost?

LED whitening costs vary depending on your dental condition, how you whiten them and how you look after them. Severely stained teeth will cost more to whiten because they will likely need more and possibly stronger treatments. Here are some examples of different methods of teeth whitening for you to compare:

At Home Treatments

Non-prescription teeth whitening products can be the cheapest route to a Hollywood smile and can be very effective. Dental professionals agree that it can be an effective way to whiten teeth.

Duration: 1 hour or less, depending on the formula

Effectiveness: a few months to years

Overall Cost: $20-$100

If you are intersted in at-home teeth whitening, you may be interested to see what the OGLF Team thought of some of the most popular products on the market.

Whitening Sessions At The Dentists

The results last longer but will cost you much more. The full total will depend on the degree of tooth discoloration, the length and number of sessions, and the utilization of more advanced whitening treatments like LED teeth whitening procedure.

Duration: 1 hour or less

Effectiveness: 1-3 years

Overall Cost: $500-1000

Keep in mind that the best teeth whitening treatment results can also involve other teeth cleaning or post-whitening dental procedures that the dentist will recommend – all of which can contribute to the final cost. Many dental practices offer repayment plans and third-party financing options, but these will rarely be covered by your health insurance.

How Can I Maximise My Results From Teeth Whitening?

Maximise Teeth Whitening Results

No matter which method you are using for whitening your teeth, you want to get the most for you money. Therefore, you want the whitening result to last as long as possible. These are our tips for helping to keep your teeth white:

  • Maintain good oral hygiene – cleaning your teeth will remove debris from food that can cause stains and will reduce the rate of tartar and plaque build-up. Brush your teeth for 2 minutes at least twice a day with a fluoride-based tooth paste, floss daily and use a mouthwash regularly. You can read our review of the best water flossers if you haven’t already tried one!
  • Follow the instructions – over bleaching can cause worse yellowing in the long run, so don’t exceed the recommended time or number of treatments. Also, make sure that your teeth are freshly cleaned before whitening them.
  • Avoid staining foods – give your teeth a few hours break after your teeth whitening treatments and avoid consuming foods or drinks other than water for a couple of hours. Ideally, cut staining foods and drinks such as coffee, red wine, tomato sauce and curries from your diet completely.
  • Use a straw – for acidic beverages such as orange juice and sodas (even sugar free sodas are acidic). This is also a solution for stain-causing drinks because it prevents the drinks from coming into contact with the surface of your teeth.
  • Have regular checkups – your dentist or hygienist will give you personal advice on how your teeth are holding up. They will check for cavities and decay and can give you a scale and polish to remove tartar which can lengthen the life of your whitening procedure.