Teeth whitening: “What is it all about?”

Teeth Whitening has become one of the most heavily advertised and sought after cosmetic dental procedures in the 21^st Century.  What is it all about though?

What is it all about?

Teeth whitening is all about changing of the colour of the teeth to a lighter version of what you already have.

All whitening materials use a peroxide based material, be it Carbamide Peroxide or Hydrogen Peroxide, of differing concentrations.  For professionally applied materials, the concentration ranges from 3-30 per cent Hydrogen Peroxide and 10-28 per cent Carbamide Peroxide.  Hydrogen Peroxide is about 3 times as strong as Carbamide Peroxide.  The peroxide materials break down long chain molecules into shorter chain molecules, which changes the optical appearance of the molecules, therefore creating a lighter colour.

The molecule size of the peroxide materials is small enough that it can pass through the tooth structure into the pulp (nerve and vascular supply of the teeth).

How is it done?

There are two main systems in use:

1. In Chair/ In Surgery Whitening e.g  BriteSmile, Zoom, Quick Smile, Laser Whitening
2. At Home Tooth Whitening e.g Pola Day, Pola Night, Opalesence, Night White.

In Chair / In Surgery Teeth Whitening

These systems rely on using the stronger concentration ranges of the materials, accelerating the activity by using heat or cool blue light.  The trouble with the heat producing systems (those using a heat light) is that they have the ability to harm the pulpal tooth tissue.  The pulpal tooth tissue should not be heated as it can cause long term side effects such as nerve damage, which can lead to other unnecessary treatment.  This author prefers to use the BriteSmile “in chair” system.  The BriteSmile system uses the cool blue light, drastically reducing the possibility of long term side effects.

At Home Teeth Whitening

The most common version of this system is when the Dental Practitioner makes some thin, mouthguard like trays for the patient.  These trays are filled with a whitening gel and the patient wears the trays daily over a period of 2-3 weeks, until the desired effects are reached.

Will the Results Differ Between the Two Systems?

The short answer to this question is no.  If the patient is compliant and carries out the necessary number of applications with the “at home” system, usually 10-14, then the results are the same as the “in chair” systems.  The main problem with “at home” teeth whitening is patient compliance, carrying out the necessary applications of the material.  Generally speaking, most patients are diligent for 3-4 days, therefore never really achieving the great results that “at home” teeth whitening can achieve.

This is why the “in chair” systems are often better to use.  It removes the biggest problem with “at home” teeth whitening, which is patient compliance.  The different systems have vastly different levels of the short term transient side effects that come with teeth whitening.

The ideal scenario is if patients are encouraged to use both systems.   This means that the patient undergoes a session of “in chair” whitening so that the teeth change colour within a limited time frame, but then an “at home” kit is also used for  2-3 days following this session to stabilise the colour.  The reason for this is that up to 40% of colour change from the “in chair” system is dehydration of the teeth.  Thus, as the teeth rehydrate, the colour fades.  The “at home” teeth whitening helps to maintain the initial colour change, but also allows the patient to touch up the colour over the long term, with little expense.  It is important to enable the patient to touch up the colour because the colour will fade over 2-3 years.

What are the most common side effects?

The most common side effects are;

1. Tooth Sensitivity;
2. Gum Soreness;
3. Sore Throat;
4. Nausea; and/or
5. De-mineralisation of the enamel (outside tooth structure)

The most common side effects are tooth sensitivity and gum soreness.  The literature has revealed that some people do get a sore throat and a little nausea, but really only from the “at home” system, and only rarely.

The tooth sensitivity is from the materials passing into the pulpal tissue and causing an inflammatory response.  The gum soreness can be from the peroxide materials irritating the tissues or, interestingly, it can be caused by trauma from the egdes of  the trays pressing into the gums, and not the whitening materials at all.

In the literature, the de-mineralising of the tooth tissue has been likened to drinking a can of coke.  This is easily and quickly reversed by the saliva.  This is a normal, everyday event that happens in the mouth.  Teeth whitening is only an issue in this regards if carried out all the time, over many years.  Once again, the damage can be reversed and controlled with proper instruction.

The side effects generally subside within 7 days, after the whitening has been completed

Conclusion

Teeth Whitening is highly successful and safe to use under the proper supervision of a dental professional.  The most successful protocol to follow for overall good colour change and high patient satisfaction, is a combination of both the “in chair” and “at home” teeth whitening systems.  This allows the patient to start from a very good colour change position and then take control of stabilising and touching up the colour at their own discretion, cheaply.  This increases long term patient satisfaction.  There are some transient short term side effects.  It is therefore necessary to be under the care of a trained dental professional when undergoing teeth whitening.