12 things to think about when deciding on teeth whitening

In 2019, the Australian Dental Association (ADA) reported on a surge in popularity of teeth whitening. Teeth whitening is a very popular choice for people who wish to have whiter, brighter teeth, free from stains coming from red wine, certain foods or smoking. However, the benefits of having whiter teeth extend far beyond the cosmetic aspect, with people noticing decreased amounts of oral bacteria, as well as increased self-confidence.

If you’re thinking about whitening your teeth, you want to have all the information you need so that you can make a clear choice. For example, you might want to know more about:

• the difference between the two main agents used in teeth whitening
• the difference between getting your teeth whitened at the dentist compared to getting them whitened at a cosmetic salon in a shopping centre
• the Australian teeth whitening regulations.

Please look at our frequently asked questions to help you decide about teeth whitening.

1. What is teeth whitening gel made of?

Teeth whitening gel uses one of two active ingredients to gradually whiten the surface of your teeth: carbamide peroxide or hydrogen peroxide. Peroxides are compounds used in bleaching items such as paper, clothing and, in a dental context, teeth. These gels contain either hydrogen peroxide or carbamide peroxide at different concentrations.

2. What’s the difference between hydrogen peroxide and carbamide peroxide?

Both chemicals contain oxygen, which bleaches teeth. Hydrogen peroxide contains hydrogen, while carbamide peroxide contains other elements that help make it a more stable compound than hydrogen peroxide.

Skip to the next question if you don’t want a more scientific explanation!

Hydrogen peroxide is the most elementary definition of a peroxide: it comprises two hydroxyl groups bonded together (HO-OH). You just can’t get a simpler peroxide compound. The hydroxyl groups are quite reactive, with the hydrogen atoms particularly keen to react with other chemicals. This means that hydrogen peroxide is not as stable as some other peroxides, though it bleaches teeth quickly.

This is where carbamide peroxide comes in. In addition to containing the two hydroxyl groups, it contains urea. Urea is a naturally-ocurring compound made up of an oxygen atom double-bonded to two amino groups (-NH2). The amino groups make carbamide peroxide weaker, but more stable than its hydrogen cousin. These factors also lead to carbamide peroxide taking a longer time to bleach teeth.

Both compounds contain the two hydroxyl groups, which facilitate teeth bleaching. They both act as strong oxidising agents, and can cause skin irritation and eye damage at high concentrations. Please note that dentists and cosmetic whitening salons do NOT use peroxides at concentrations high enough to cause these oxidising effects.

3. Does carbamide peroxide have a longer shelf life than hydrogen peroxide?

Because carbamide peroxide is a more stable compound than hydrogen peroxide, it has a slightly longer shelf life. As this difference is only slight, both whitening agents benefit from being stored in a refrigerated environment. Both peroxide compounds will be less effective if stored at room temperature.

4. Which compound works better?

Both compounds provide effective whitening results. However, because hydrogen peroxide is faster-acting, it does give whiter results more quickly.

5. How long does a peroxide treatment take?

Hydrogen peroxide acts more quickly than carbamide peroxide. Therefore, it takes about 15-20 minutes for whitening using hydrogen peroxide and about 20-25 minutes for the carbamide peroxide treatment. These times are for in-chair whitening treatment at the dental surgery. At-home whitening times are usually anywhere between 2-3 hours up to overnight.

6. Is one peroxide better for people with teeth sensitivity?

When applied correctly and using appropriate concentrations (6% for hydrogen peroxide and 18% for carbamide peroxide), it’s rare for patients to experience tooth sensitivity. Patients can use tooth mousse and desensitising toothpaste with their teeth whitening treatments. Using these products will help to reduce teeth sensitivity.

7. Does one agent cause more rebound?

When teeth appear lighter immediately after whitening but lose brilliance after a short time, this is called rebound. Neither hydrogen peroxide nor carbamide peroxide cause rebound, and our whitening agents contain higher water content to keep the teeth hydrated and reduce rebound.

8. Are there laws in Australia about who can apply teeth whitening treatments?

• Only dentists can legally use teeth whitening products containing above 6% hydrogen peroxide or over 18% carbamide peroxide in Australia. These whitening treatments can only be applied in an in-chair dental setting.
• Take-home dental whitening kits from a dental clinic can contain peroxide concentrations under 6% for hydrogen peroxide or 18% for carbamide peroxide. The dentist can prescribe take-home kits with higher peroxide concentrations as needed.
• Cosmetic whitening salon operators must use whitening agents containing peroxide concentrations under 6% for hydrogen peroxide or 18% for carbamide peroxide.
• We have Australian laws, guidelines, & restrictions surrounding cosmetic teeth whitening to keep consumers safe and ensure correct compliance to requirements for dental and salon providers. The Australian regulations further provide that whitening products contain approved agents only, like peroxides. They also act to reduce poor or misleading advertising about cosmetic whitening.

9. Teeth whitening at a dentist vs at a salon. What’s the difference?

Whitening at a dentist and whitening at a salon both use LED light to activate the peroxide whitening gel. The main differences include:

• stronger peroxide concentrations at a dentist compared to a cosmetic salon.
• 15-20 minutes total treatment time at the dentist vs 20-30 minutes treatment time at the salon.
• training & education: cosmetic salon staff don’t complete nationally-recognised training, and can complete a 3-day training course with no prior experience. Professionals providing whitening services at dental clinics are degree-educated and undertake ongoing professional learning.

10. How long does teeth whitening last?

When you have a teeth whitening treatment in the dental chair, you can expect results to last for 6-12 months, after four whitening sessions each lasting 15 minutes.

When you have a teeth whitening treatment in the comfort and privacy of your own home, they should expect to undertake at least four applications in the first week to achieve noticeable results. Follow-up at-home whitening usually requires ongoing weekly treatments.

11. Do I get a personalised, fitted mouthguard when I get my teeth whitening treatment?

When you select a dentist for a whitening treatment, you will receive a customised mouthguard. It’s an individualised, custom-made tray to apply the whitening gel. The tray is similar to a mouthguard but much finer in structure.

If you choose an at-home treatment, you’ll receive the whitening agents and the trays, which you then affix to your teeth for the recommended time. At-home kits also include a set of instructions about tray care and storage.

If you come to the dental clinic for in-chair whitening treatment, you’ll also receive your set of individualised gel trays. The dental clinic stores the trays on-site for repeated visits.

Because cosmetic salon operators are not trained dental professionals, they cannot supply an individualised set of whitening trays for each customer. Using trays or mouthguards which aren’t individually customised can lead to burnt gums or patchy whitening gel application.

12. Are dental examinations included in the price of in-chair whitening treatments?

When you select a dentist for a whitening treatment, you’re choosing the whitening treatment only. Dentists will recommend a general dental check-up or examination before beginning a course of whitening treatment. You want to make sure your teeth are in good health before committing to treatment.

Are you ready for a brighter smile?

When you know that all dental practitioners at our Richmond clinic are experienced teeth whitening professionals, you can feel happy choosing our clinic. Our people have ongoing and updated training in this area and they’re skilled and caring during all stages of the treatment. Our in-chair and take-home offerings use Zoom whitening products. The Zoom LED light therapy is an integral part of the in-chair whitening experience.